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Asatryan B, Barth AS. Sex-related differences in incidence, phenotype and risk of sudden cardiac death in inherited arrhythmia syndromes. Front Cardiovasc Med 2023; 9:1010748. [PMID: 36684594 PMCID: PMC9845907 DOI: 10.3389/fcvm.2022.1010748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 12/08/2022] [Indexed: 01/06/2023] Open
Abstract
Inherited Arrhythmia Syndromes (IAS) including long QT and Brugada Syndrome, are characterized by life-threatening arrhythmias in the absence of apparent structural heart disease and are caused by pathogenic variants in genes encoding cardiac ion channels or associated proteins. Studies of large pedigrees of families affected by IAS have demonstrated incomplete penetrance and variable expressivity. Biological sex is one of several factors that have been recognized to modulate disease severity in IAS. There is a growing body of evidence linking sex hormones to the susceptibility to arrhythmias, yet, many sex-specific disease aspects remain underrecognized as female sex and women with IAS are underinvestigated and findings from male-predominant cohorts are often generalized to both sexes with minimal to no consideration of relevant sex-associated differences in prevalence, disease manifestations and outcome. In this review, we highlight current knowledge of sex-related biological differences in normal cardiac electrophysiology and sex-associated factors that influence IAS phenotypes.
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Affiliation(s)
- Babken Asatryan
- Department of Cardiology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Andreas S. Barth
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States,*Correspondence: Andreas S. Barth ✉
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Zhang J, Zou Y, Chen X, Pan J, Yu H, Wang Y, Wu Y, Zou H. Extremely dangerous hypopituitarism related long QT syndrome and transient ST-segment elevation: A case report. SAGE Open Med Case Rep 2023; 11:2050313X221147194. [PMID: 36636098 PMCID: PMC9829875 DOI: 10.1177/2050313x221147194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 12/07/2022] [Indexed: 01/14/2023] Open
Abstract
Acquired long QT syndrome caused by hypopituitarism and transient ST-segment elevation has not been reported in cardiac arrest patients. We report a case of extremely dangerous acquired long QT syndrome and transient ST-segment elevation. A 44-year-old Chinese woman with renal failure experienced sudden cardiac arrest in the haemodialysis room. Subsequent electrocardiogram showed QT prolongation and transient ST-segment elevation. This patient's medical history, subsequent laboratory results and pituitary magnetic resonance imaging suggested hypopituitarism. Transient ST-segment elevation on the electrocardiogram was considered to be caused by repeated direct current shocks. The patient was diagnosed with acquired long QT syndrome and was not taking any antiarrhythmic drugs. Her corrected QT interval normalized after hormone replacement therapy. This case highlights the importance of the awareness of hypopituitarism; early identification and intervention can prevent the occurrence of this life-threatening arrhythmia. ST-segment elevation is not always due to acute myocardial infarction, and a variety of other causes, especially electrical cardioversion, should be considered.
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Affiliation(s)
- Jia Zhang
- Department of Inspection Medical, Wenzhou People’s Hospital, The Wenzhou Third Clinical Institute Affiliated with Wenzhou Medical University, Wenzhou, China
| | - Yingying Zou
- Digestive System Department, The Third Affiliated Hospital of Qiqihar Medical College, Qiqihar, China
| | - Xiaoshu Chen
- Department of Cardiovascular Medicine, Wenzhou People’s Hospital, The Wenzhou Third Clinical Institute Affiliated with Wenzhou Medical University, Wenzhou, China
| | - Jingye Pan
- Department of General and Intensive Care Medical, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Haizhu Yu
- Department of General Practice, Zhejiang Hospital, Hangzhou, China
| | - Yi Wang
- Department of Cardiovascular Medicine, Wenzhou People’s Hospital, The Wenzhou Third Clinical Institute Affiliated with Wenzhou Medical University, Wenzhou, China
| | - Yanran Wu
- Department of Cardiovascular Medicine, Wenzhou People’s Hospital, The Wenzhou Third Clinical Institute Affiliated with Wenzhou Medical University, Wenzhou, China
| | - He Zou
- Department of Cardiovascular Medicine, Wenzhou People’s Hospital, The Wenzhou Third Clinical Institute Affiliated with Wenzhou Medical University, Wenzhou, China,He Zou, Department of Cardiovascular Medicine, Wenzhou People’s Hospital, The Wenzhou Third Clinical Institute Affiliated with Wenzhou Medical University, Wenzhou 325035, Zhejiang, China.
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Viskin S. Long QT begets long QT. J Cardiovasc Electrophysiol 2023; 34:177-179. [PMID: 36335630 DOI: 10.1111/jce.15736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 10/27/2022] [Indexed: 11/08/2022]
Affiliation(s)
- Sami Viskin
- Department of Cardiology, Tel Aviv Sourasky Medical Center and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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Prakash O, Gupta N, Milburn A, McCormick L, Deugi V, Fisch P, Wyles J, Thomas NL, Antonyuk S, Dart C, Helassa N. Calmodulin variant E140G associated with long QT syndrome impairs CaMKIIδ autophosphorylation and L-type calcium channel inactivation. J Biol Chem 2023; 299:102777. [PMID: 36496072 DOI: 10.1016/j.jbc.2022.102777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 11/29/2022] [Accepted: 12/01/2022] [Indexed: 12/13/2022] Open
Abstract
Long QT syndrome (LQTS) is a human inherited heart condition that can cause life-threatening arrhythmia including sudden cardiac death. Mutations in the ubiquitous Ca2+-sensing protein calmodulin (CaM) are associated with LQTS, but the molecular mechanism by which these mutations lead to irregular heartbeats is not fully understood. Here, we use a multidisciplinary approach including protein biophysics, structural biology, confocal imaging, and patch-clamp electrophysiology to determine the effect of the disease-associated CaM mutation E140G on CaM structure and function. We present novel data showing that mutant-regulated CaMKIIδ kinase activity is impaired with a significant reduction in enzyme autophosphorylation rate. We report the first high-resolution crystal structure of a LQTS-associated CaM variant in complex with the CaMKIIδ peptide, which shows significant structural differences, compared to the WT complex. Furthermore, we demonstrate that the E140G mutation significantly disrupted Cav1.2 Ca2+/CaM-dependent inactivation, while cardiac ryanodine receptor (RyR2) activity remained unaffected. In addition, we show that the LQTS-associated mutation alters CaM's Ca2+-binding characteristics, secondary structure content, and interaction with key partners involved in excitation-contraction coupling (CaMKIIδ, Cav1.2, RyR2). In conclusion, LQTS-associated CaM mutation E140G severely impacts the structure-function relationship of CaM and its regulation of CaMKIIδ and Cav1.2. This provides a crucial insight into the molecular factors contributing to CaM-mediated arrhythmias with a central role for CaMKIIδ.
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Juhl CR, Burgdorf J, Knudsen C, Lubberding AF, Veedfald S, Isaksen JL, Hartmann B, Frikke-Schmidt R, Mandrup-Poulsen T, Holst JJ, Kanters JK, Torekov SS. A randomized, double-blind, crossover study of the effect of the fluoroquinolone moxifloxacin on glucose levels and insulin sensitivity in young men and women. Diabetes Obes Metab 2023; 25:98-109. [PMID: 36054143 PMCID: PMC10087839 DOI: 10.1111/dom.14851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 08/15/2022] [Accepted: 08/22/2022] [Indexed: 12/14/2022]
Abstract
AIM The voltage-gated potassium channel Kv 11.1 is important for repolarizing the membrane potential in excitable cells such as myocytes, pancreatic α- and β-cells. Moxifloxacin blocks the Kv 11.1 channel and increases the risk of hypoglycaemia in patients with diabetes. We investigated glucose regulation and secretion of glucoregulatory hormones in young people with and without moxifloxacin, a drug known to block the Kv 11.1 channel. MATERIALS AND METHODS The effect of moxifloxacin (800 mg/day for 4 days) or placebo on glucose regulation was assessed in a randomized, double-blind, crossover study of young men and women (age 20-40 years and body mass index 18.5-27.5 kg/m2 ) without chronic disease, using 6-h oral glucose tolerance tests and continuous glucose monitoring. RESULTS Thirty-eight participants completed the study. Moxifloxacin prolonged the QTcF interval and increased heart rate. Hypoglycaemia was more frequently observed with moxifloxacin, both during the 8 days of continuous glucose monitoring and during the oral glucose tolerance tests. Hypoglycaemia questionnaire scores were higher after intake of moxifloxacin. Moxifloxacin reduced the early plasma-glucose response (AUC0-30 min ) by 7% (95% CI: -9% to -4%, p < .01), and overall insulin response (AUC0-360 min ) decreased by 18% (95% CI: -24% to -11%, p < .01) and plasma glucagon increased by 17% (95% CI: 4%-33%, p = .03). Insulin sensitivity calculated as the Matsuda index increased by 11%, and MISI, an index of muscle insulin sensitivity, increased by 34%. CONCLUSIONS In young men and women, moxifloxacin, a drug known to block the Kv 11.1 channel, increased QT interval, decreased glucose levels and was associated with increased muscle insulin sensitivity and more frequent episodes of hypoglycaemia.
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Affiliation(s)
- Christian R Juhl
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Josephine Burgdorf
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Cecilie Knudsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anniek F Lubberding
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Simon Veedfald
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jonas L Isaksen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ruth Frikke-Schmidt
- Department of Clinical Biochemistry, Copenhagen University Hospital-Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Mandrup-Poulsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jørgen K Kanters
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Signe S Torekov
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Lammoglia BC, Hasselmann G, Pires-Oliveira M, Duarte Nicolau LA, Rolim Medeiros JV, Sabia Tallo F, Omar Taha M, Yamaguti Lima R, Caricati-Neto A, Menezes-Rodrigues FS. Risk of Cardiac Lesion with Chronic and Acute Use of Loperamide-An Integrative Review. J Cardiovasc Dev Dis 2022; 9. [PMID: 36547428 DOI: 10.3390/jcdd9120431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 11/22/2022] [Accepted: 11/28/2022] [Indexed: 12/12/2022] Open
Abstract
Loperamide is a synthetic opioid commonly used as an antidiarrheal due to its activation of u-opioid receptors in the myenteric plexus. In therapeutic doses, it inhibits peristalsis and has anti-secretory and anti-motility effects, until metabolized by intestinal and hepatic CYP3A4 and CYP2C8 into inactive metabolites. Furthermore, loperamide also inhibits L-type voltage-gated calcium (Ca2+) channels, increases action potential duration, and can induce arrhythmias and even cardiotoxicity, particularly when taken in extremely high doses. Thus, the aim of this study was to perform an integrative review of the available evidence in the recent literature on the cardiac risks of acute and chronic use of loperamide. In electrocardiogram (ECG) analysis, the most common finding was QTc prolongation in 27 cases, followed by QRS prolongation, first-degree atrioventricular (AV) block, torsades de pointes, ventricular tachycardia, and right bundle branch block. As for the symptoms encountered, syncope, weakness, palpitations, lightheadedness, shortness of breath, nausea, vomiting, bradycardia, and cardiac arrest were the most common. Loperamide can inhibit hERG voltage-gated potassium (K+) channels (Kv11.1), leading to the prolongation of repolarization, QTc interval prolongation, and increased risk of torsades de pointes. In addition, loperamide can inhibit voltage-gated sodium (Na+) channels (Nav1.5), impairing electrical cardiac conduction and potentiating QRS interval widening. Therefore, QTc prolongation, torsades de pointes, and other ECG alterations are of particular concern regarding loperamide toxicity, particularly when overdosed.
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O’Neill MJ, Wada Y, Hall LD, Mitchell DW, Glazer AM, Roden DM. Functional Assays Reclassify Suspected Splice-Altering Variants of Uncertain Significance in Mendelian Channelopathies. Circ Genom Precis Med 2022; 15:e003782. [PMID: 36197721 PMCID: PMC9772980 DOI: 10.1161/circgen.122.003782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 07/12/2022] [Indexed: 12/24/2022]
Abstract
BACKGROUND Rare protein-altering variants in SCN5A, KCNQ1, and KCNH2 are major causes of Brugada syndrome and the congenital long QT syndrome. While splice-altering variants lying outside 2-bp canonical splice sites can cause these diseases, their role remains poorly described. We implemented 2 functional assays to assess 12 recently reported putative splice-altering variants of uncertain significance and 1 likely pathogenic variant without functional data observed in Brugada syndrome and long QT syndrome probands. METHODS We deployed minigene assays to assess the splicing consequences of 10 variants. Three variants incompatible with the minigene approach were introduced into control induced pluripotent stem cells by CRISPR genome editing. We differentiated cells into induced pluripotent stem cell-derived cardiomyocytes and studied splicing outcomes by reverse transcription-polymerase chain reaction. We used the American College of Medical Genetics and Genomics functional assay criteria (PS3/BS3) to reclassify variants. RESULTS We identified aberrant splicing, with presumed disruption of protein sequence, in 8/10 variants studied using the minigene assay and 1/3 studied in induced pluripotent stem cell-derived cardiomyocytes. We reclassified 8 variants of uncertain significance to likely pathogenic, 1 variant of uncertain significance to likely benign, and 1 likely pathogenic variant to pathogenic. CONCLUSIONS Functional assays reclassified splice-altering variants outside canonical splice sites in Brugada Syndrome- and long QT syndrome-associated genes.
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Affiliation(s)
- Matthew J. O’Neill
- Vanderbilt University School of Medicine, Medical Scientist
Training Program, Vanderbilt University
| | - Yuko Wada
- Vanderbilt Center for Arrhythmia Research and Therapeutics
(VanCART), Division of Clinical Pharmacology, Department of Medicine
| | - Lynn D. Hall
- Vanderbilt Center for Arrhythmia Research and Therapeutics
(VanCART), Division of Clinical Pharmacology, Department of Medicine
| | - Devyn W. Mitchell
- Vanderbilt Center for Arrhythmia Research and Therapeutics
(VanCART), Division of Clinical Pharmacology, Department of Medicine
| | - Andrew M. Glazer
- Vanderbilt Center for Arrhythmia Research and Therapeutics
(VanCART), Division of Clinical Pharmacology, Department of Medicine
| | - Dan M. Roden
- Vanderbilt Center for Arrhythmia Research and Therapeutics
(VanCART), Departments of Medicine, Pharmacology, and Biomedical Informatics,
Vanderbilt University Medical Center, Nashville, TN
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58
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Bains S, Zhou W, Dotzler SM, Martinez K, Kim CJ, Tester DJ, Ye D, Ackerman MJ. Suppression and Replacement Gene Therapy for KCNH2-Mediated Arrhythmias. Circ Genom Precis Med 2022; 15:e003719. [PMID: 36252106 DOI: 10.1161/circgen.122.003719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND KCNH2-mediated arrhythmia syndromes are caused by loss-of-function (type 2 long QT syndrome [LQT2]) or gain-of-function (type 1 short QT syndrome [SQT1]) pathogenic variants in the KCNH2-encoded Kv11.1 potassium channel, which is essential for the cardiac action potential. METHODS A dual-component "suppression-and-replacement" (SupRep) KCNH2 gene therapy was created by cloning into a single construct a custom-designed KCNH2 short hairpin RNA with ~80% knockdown (suppression) and a "short hairpin RNA-immune" KCNH2 cDNA (replacement). Induced pluripotent stem cell-derived cardiomyocytes and their CRISPR-Cas9 variant-corrected isogenic control (IC) induced pluripotent stem cell-derived cardiomyocytes were made for 2 LQT2- (G604S, N633S) and 1 SQT1- (N588K) causative variants. All variant lines were treated with KCNH2-SupRep or non-targeting control short hairpin RNA (shCT). The action potential duration (APD) at 90% repolarization (APD90) was measured using FluoVolt voltage dye. RESULTS KCNH2-SupRep achieved variant-independent rescue of both pathologic phenotypes. For LQT2-causative variants, treatment with KCNH2-SupRep resulted in shortening of the pathologically prolonged APD90 to near curative (IC-like) APD90 levels (G604S IC, 471±25 ms; N633S IC, 405±55 ms) compared with treatment with shCT (G604S: SupRep-treated, 452±76 ms versus shCT-treated, 550±41 ms; P<0.0001; N633S: SupRep-treated, 399±105 ms versus shCT-treated, 577±39 ms, P<0.0001). Conversely, for the SQT1-causative variant, N588K, treatment with KCNH2-SupRep resulted in therapeutic prolongation of the pathologically shortened APD90 (IC: 429±16 ms; SupRep-treated: 396±61 ms; shCT-treated: 274±12 ms). CONCLUSIONS We provide the first proof-of-principle gene therapy for correction of both LQT2 and SQT1. KCNH2-SupRep gene therapy successfully normalized the pathologic APD90, thereby eliminating the pathognomonic feature of both LQT2 and SQT1.
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Affiliation(s)
- Sahej Bains
- Medical Scientist Training Program (S.B., S.M.D.), Mayo Clinic, Rochester, MN.,Department of Molecular Pharmacology and Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory) (S.B., W.Z., S.M.D., K.M., C.S.J.K., D.J.T., D.Y., M.J.A.), Mayo Clinic, Rochester, MN
| | - Wei Zhou
- Department of Molecular Pharmacology and Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory) (S.B., W.Z., S.M.D., K.M., C.S.J.K., D.J.T., D.Y., M.J.A.), Mayo Clinic, Rochester, MN
| | - Steven M Dotzler
- Medical Scientist Training Program (S.B., S.M.D.), Mayo Clinic, Rochester, MN.,Department of Molecular Pharmacology and Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory) (S.B., W.Z., S.M.D., K.M., C.S.J.K., D.J.T., D.Y., M.J.A.), Mayo Clinic, Rochester, MN
| | - Katherine Martinez
- Department of Molecular Pharmacology and Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory) (S.B., W.Z., S.M.D., K.M., C.S.J.K., D.J.T., D.Y., M.J.A.), Mayo Clinic, Rochester, MN
| | - Cs John Kim
- Department of Molecular Pharmacology and Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory) (S.B., W.Z., S.M.D., K.M., C.S.J.K., D.J.T., D.Y., M.J.A.), Mayo Clinic, Rochester, MN
| | - David J Tester
- Department of Molecular Pharmacology and Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory) (S.B., W.Z., S.M.D., K.M., C.S.J.K., D.J.T., D.Y., M.J.A.), Mayo Clinic, Rochester, MN.,Department of Pediatric and Adolescent Medicine, Division of Pediatric Cardiology (D.J.T., M.J.A.), Mayo Clinic, Rochester, MN
| | - Dan Ye
- Department of Molecular Pharmacology and Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory) (S.B., W.Z., S.M.D., K.M., C.S.J.K., D.J.T., D.Y., M.J.A.), Mayo Clinic, Rochester, MN.,Division of Heart Rhythm Services, Department of Cardiovascular Medicine, Windland Smith Rice Genetic Heart Rhythm Clinic (D.J.T., M.J.A.), Mayo Clinic, Rochester, MN
| | - Michael J Ackerman
- Department of Molecular Pharmacology and Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory) (S.B., W.Z., S.M.D., K.M., C.S.J.K., D.J.T., D.Y., M.J.A.), Mayo Clinic, Rochester, MN.,Department of Pediatric and Adolescent Medicine, Division of Pediatric Cardiology (D.J.T., M.J.A.), Mayo Clinic, Rochester, MN.,Division of Heart Rhythm Services, Department of Cardiovascular Medicine, Windland Smith Rice Genetic Heart Rhythm Clinic (D.J.T., M.J.A.), Mayo Clinic, Rochester, MN
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Zou X, Wu X, Sampson KJ, Colecraft HM, Larsson HP, Kass RS. Pharmacological rescue of specific long QT variants of KCNQ1/KCNE1 channels. Front Physiol 2022; 13:902224. [PMID: 36505078 PMCID: PMC9726718 DOI: 10.3389/fphys.2022.902224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 11/02/2022] [Indexed: 11/24/2022] Open
Abstract
The congenital Long QT Syndrome (LQTS) is an inherited disorder in which cardiac ventricular repolarization is delayed and predisposes patients to cardiac arrhythmias and sudden cardiac death. LQT1 and LQT5 are LQTS variants caused by mutations in KCNQ1 or KCNE1 genes respectively. KCNQ1 and KCNE1 co-assemble to form critical IKS potassium channels. Beta-blockers are the standard of care for the treatment of LQT1, however, doing so based on mechanisms other than correcting the loss-of-function of K+ channels. ML277 and R-L3 are compounds that enhance IKS channels and slow channel deactivation in a manner that is dependent on the stoichiometry of KCNE1 subunits in the assembled channels. In this paper, we used expression of IKS channels in Chinese hamster ovary (CHO) cells and Xenopus oocytes to study the potential of these two drugs (ML277 and R-L3) for the rescue of LQT1 and LQT5 mutant channels. We focused on the LQT1 mutation KCNQ1-S546L, and two LQT5 mutations, KCNE1-L51H and KCNE1-G52R. We found ML277 and R-L3 potentiated homozygote LQTS mutations in the IKS complexes-KCNE1-G52R and KCNE1-L51H and in heterogeneous IKS channel complexes which mimic heterogeneous expression of mutations in patients. ML277 and R-L3 increased the mutant IKS current amplitude and slowed current deactivation, but not in wild type (WT) IKS. We obtained similar results in the LQT1 mutant (KCNQ1 S546L/KCNE1) with ML277 and R-L3. ML277 and R-L3 had a similar effect on the LQT1 and LQT5 mutants, however, ML277 was more effective than R-L3 in this modulation. Importantly we found that not all LQT5 mutants expressed with KCNQ1 resulted in channels that are potentiated by these drugs as the KCNE1 mutant D76N inhibited drug action when expressed with KCNQ1. Thus, our work shows that by directly studying the treatment of LQT1 and LQT5 mutations with ML277 and R-L3, we will understand the potential utility of these activators as options in specific LQTS therapeutics.
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Affiliation(s)
- Xinle Zou
- Department of Molecular Pharmacology & Therapeutics, Vagelos College of Physicians & Surgeons of Columbia University Irving Medical Center, New York, NY, United States
| | - Xiaoan Wu
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, Miami, FL, United States
| | - Kevin J. Sampson
- Department of Molecular Pharmacology & Therapeutics, Vagelos College of Physicians & Surgeons of Columbia University Irving Medical Center, New York, NY, United States
| | - Henry M. Colecraft
- Department of Molecular Pharmacology & Therapeutics, Vagelos College of Physicians & Surgeons of Columbia University Irving Medical Center, New York, NY, United States
| | - H. Peter Larsson
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, Miami, FL, United States
| | - Robert S. Kass
- Department of Molecular Pharmacology & Therapeutics, Vagelos College of Physicians & Surgeons of Columbia University Irving Medical Center, New York, NY, United States,*Correspondence: Robert S. Kass,
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Dahlberg P, Axelsson K, Jensen SM, Lundahl G, Vahedi F, Perkins R, Gransberg L, Bergfeldt L. Accelerated QT adaptation following atropine-induced heart rate increase in LQT1 patients versus healthy controls: A sign of disturbed hysteresis. Physiol Rep 2022; 10:e15487. [PMID: 36324292 PMCID: PMC9630760 DOI: 10.14814/phy2.15487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 09/08/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023] Open
Abstract
Hysteresis, a ubiquitous regulatory phenomenon, is a salient feature of the adaptation of ventricular repolarization duration to heart rate (HR) change. We therefore compared the QT interval adaptation to rapid HR increase in patients with the long QT syndrome type 1 (LQT1) versus healthy controls because LQT1 is caused by loss-of-function mutations affecting the repolarizing potassium channel current IKs , presumably an important player in QT hysteresis. The study was performed in an outpatient hospital setting. HR was increased in LQT1 patients and controls by administering an intravenous bolus of atropine (0.04 mg/kg body weight) for 30 s. RR and QT intervals were recorded by continuous Frank vectorcardiography. Atropine induced transient expected side effects but no adverse arrhythmias. There was no difference in HR response (RR intervals) to atropine between the groups. Although atropine-induced ΔQT was 48% greater in 18 LQT1 patients than in 28 controls (p < 0.001), QT adaptation was on average 25% faster in LQT1 patients (measured as the time constant τ for the mono-exponential function and the time for 90% of ΔQT; p < 0.01); however, there was some overlap between the groups, possibly a beta-blocker effect. The shorter QT adaptation time to atropine-induced HR increase in LQT1 patients on the group level corroborates the importance of IKs in QT adaptation hysteresis in humans and shows that LQT1 patients have a disturbed ultra-rapid cardiac memory. On the individual level, the QT adaptation time possibly reflects the effect-size of the loss-of-function mutation, but its clinical implications need to be shown.
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Affiliation(s)
- Pia Dahlberg
- Department of Molecular and Clinical MedicineInstitute of Medicine, Sahlgrenska Academy, University of GothenburgGothenburgSweden
- Region Västra Götaland, Department of CardiologySahlgrenska University HospitalGothenburgSweden
| | - Karl‐Jonas Axelsson
- Department of Molecular and Clinical MedicineInstitute of Medicine, Sahlgrenska Academy, University of GothenburgGothenburgSweden
- Region Västra Götaland, Department of CardiologySahlgrenska University HospitalGothenburgSweden
| | - Steen M. Jensen
- Department of Public Health and Clinical Medicine, and Heart CentreUmeå UniversityUmeåSweden
| | - Gunilla Lundahl
- Department of Molecular and Clinical MedicineInstitute of Medicine, Sahlgrenska Academy, University of GothenburgGothenburgSweden
| | - Farzad Vahedi
- Department of Molecular and Clinical MedicineInstitute of Medicine, Sahlgrenska Academy, University of GothenburgGothenburgSweden
- Region Västra Götaland, Department of CardiologySahlgrenska University HospitalGothenburgSweden
| | - Rosie Perkins
- Department of Molecular and Clinical MedicineInstitute of Medicine, Sahlgrenska Academy, University of GothenburgGothenburgSweden
| | - Lennart Gransberg
- Department of Molecular and Clinical MedicineInstitute of Medicine, Sahlgrenska Academy, University of GothenburgGothenburgSweden
| | - Lennart Bergfeldt
- Department of Molecular and Clinical MedicineInstitute of Medicine, Sahlgrenska Academy, University of GothenburgGothenburgSweden
- Region Västra Götaland, Department of CardiologySahlgrenska University HospitalGothenburgSweden
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Akbuğa K, Karanfil M. Same family, same mutation, different ECG. Mol Genet Genomic Med 2022; 11:e2079. [PMID: 36305573 PMCID: PMC9834179 DOI: 10.1002/mgg3.2079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 09/01/2022] [Accepted: 10/21/2022] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Different types of long QT syndromes (LQTS) have distinct ECG manifestations according to the type and magnitude of ion channel dysfunction. While LQT1 carriers usually have broad-based T waves and LQT3 carriers have extended ST segments with relatively narrow peaked T waves; LQT2 carriers have low-amplitude T waves with high incidences of notches. METHODS We describe three members of a family with the same LQTS2 pathogenic variant, but different surface ECG findings. CONCLUSION This case shows ECG differences may also occur between family members who have pathogenic variants associated with long QT syndrome.
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Affiliation(s)
- Kürşat Akbuğa
- Cardiology Department, Faculty of MedicineTOBB ETUAnkaraTurkey
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Zhang Y, Grimwood AL, Hancox JC, Harmer SC, Dempsey CE. Evolutionary coupling analysis guides identification of mistrafficking-sensitive variants in cardiac K + channels: Validation with hERG. Front Pharmacol 2022; 13:1010119. [PMID: 36339618 PMCID: PMC9632996 DOI: 10.3389/fphar.2022.1010119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 09/30/2022] [Indexed: 09/27/2023] Open
Abstract
Loss of function (LOF) mutations of voltage sensitive K+ channel proteins hERG (Kv11.1) and KCNQ1 (Kv7.1) account for the majority of instances of congenital Long QT Syndrome (cLQTS) with the dominant molecular phenotype being a mistrafficking one resulting from protein misfolding. We explored the use of Evolutionary Coupling (EC) analysis, which identifies evolutionarily conserved pairwise amino acid interactions that may contribute to protein structural stability, to identify regions of the channels susceptible to misfolding mutations. Comparison with published experimental trafficking data for hERG and KCNQ1 showed that the method strongly predicts "scaffolding" regions of the channel membrane domains and has useful predictive power for trafficking phenotypes of individual variants. We identified a region in and around the cytoplasmic S2-S3 loop of the hERG Voltage Sensor Domain (VSD) as susceptible to destabilising mutation, and this was confirmed using a quantitative LI-COR ® based trafficking assay that showed severely attenuated trafficking in eight out of 10 natural hERG VSD variants selected using EC analysis. Our analysis highlights an equivalence in the scaffolding structures of the hERG and KCNQ1 membrane domains. Pathogenic variants of ion channels with an underlying mistrafficking phenotype are likely to be located within similar scaffolding structures that are identifiable by EC analysis.
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Affiliation(s)
- Yihong Zhang
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building, University Walk, Bristol, United Kingdom
| | - Amy L. Grimwood
- School of Biological Sciences, Life Sciences Building, Bristol, United Kingdom
| | - Jules C. Hancox
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building, University Walk, Bristol, United Kingdom
| | - Stephen C. Harmer
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building, University Walk, Bristol, United Kingdom
| | - Christopher E. Dempsey
- School of Biochemistry, Biomedical Sciences Building, University Walk, Bristol, United Kingdom
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Abstract
Cardiac memory is the term used to describe an interesting electrocardiographic phenomenon. Whenever a QRS complex is wide and abnormal, such as during ventricular pacing, the T waves will also be abnormal and will point to the opposite direction of the wide QRS. If the QRS then normalizes, such as after cessation of ventricular pacing, the T waves will normalize as well, but at a later stage. The period of cardiac memory is the phase between the sudden normalization of the QRS and the eventual and gradual return of the T waves to their baseline morphology. Cardiac memory is assumed to be an innocent electrocardiographic curiosity. However, during cardiac memory, reduction of repolarizing potassium currents increases left ventricular repolarization gradients. Therefore, when cardiac memory occurs in patients who already have a prolonged QT interval (for whatever reason), it can lead to a frank long QT syndrome with QT-related ventricular arrhythmias (torsades de pointes). These arrhythmogenic effects of cardiac memory are not generally appreciated and are reviewed here for the first time.
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Affiliation(s)
- Sami Viskin
- Department of Cardiology, Tel Aviv Sourasky Medical Center and Sackler School of Medicine, Tel Aviv University, Israel (S.V., E.C., A.L.S., R.R.)
| | - Ehud Chorin
- Department of Cardiology, Tel Aviv Sourasky Medical Center and Sackler School of Medicine, Tel Aviv University, Israel (S.V., E.C., A.L.S., R.R.)
| | - Arie Lorin Schwartz
- Department of Cardiology, Tel Aviv Sourasky Medical Center and Sackler School of Medicine, Tel Aviv University, Israel (S.V., E.C., A.L.S., R.R.)
| | - Piotr Kukla
- Department of Internal Medicine and Cardiology, Specialistic Hospital, Gorlice, Poland (P.K.)
| | - Raphael Rosso
- Department of Cardiology, Tel Aviv Sourasky Medical Center and Sackler School of Medicine, Tel Aviv University, Israel (S.V., E.C., A.L.S., R.R.)
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Wang M, Peterson DR, Pagan E, Bagnardi V, Mazzanti A, McNitt S, Rich DQ, Seplaki CL, Kutyifa V, Polonsky B, Barsheshet A, Kukavica D, Rosero S, Goldenberg I, Priori S, Zareba W. Assessment of absolute risk of life-threatening cardiac events in long QT syndrome patients. Front Cardiovasc Med 2022; 9:988951. [PMID: 36277779 PMCID: PMC9585302 DOI: 10.3389/fcvm.2022.988951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 09/01/2022] [Indexed: 12/04/2022] Open
Abstract
Background Risk stratification in long QT syndrome (LQTS) patients is important for optimizing patient care and informing clinical decision making. We developed a risk prediction algorithm with prediction of 5-year absolute risk of the first life-threatening arrhythmic event [defined as aborted cardiac arrest, sudden cardiac death, or appropriate implantable cardioverter defibrillator (ICD) shock] in LQTS patients, accounting for individual risk factors and their changes over time. Methods Rochester-based LQTS Registry included the phenotypic cohort consisting of 1,509 LQTS patients with a QTc ≥ 470 ms, and the genotypic cohort including 1,288 patients with single LQT1, LQT2, or LQT3 mutation. We developed two separate risk prediction models which included pre-specified time-dependent covariates of beta-blocker use, syncope (never, syncope while off beta blockers, and syncope while on beta blockers), and sex by age < and ≥13 years, baseline QTc, and genotype (for the genotypic cohort only). Follow-up started from enrollment in the registry and was censored at patients’ 50s birthday, date of death due to reasons other than sudden cardiac death, or last contact, whichever occurred first. The predictive models were externally validated in an independent cohort of 1,481 LQTS patients from Pavia, Italy. Results In Rochester dataset, there were 77 endpoints in the phenotypic cohort during a median follow-up of 9.0 years, and 47 endpoints in the genotypic cohort during a median follow-up of 9.8 years. The time-dependent extension of Harrell’s generalized C-statistics for the phenotypic model and genotypic model were 0.784 (95% CI: 0.740–0.827) and 0.785 (95% CI: 0.721–0.849), respectively, in the Rochester cohort. The C-statistics obtained from external validation in the Pavia cohort were 0.700 (95% CI: 0.610–0.790) and 0.711 (95% CI: 0.631–0.792) for the two models, respectively. Based on the above models, an online risk calculator estimating a 5-year risk of life-threatening arrhythmic events was developed. Conclusion This study developed two risk prediction algorithms for phenotype and genotype positive LQTS patients separately. The estimated 5-year absolute risk can be used to quantify a LQTS patient’s risk of developing life-threatening arrhythmic events and thus assisting in clinical decision making regarding prophylactic ICD therapy.
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Affiliation(s)
- Meng Wang
- Division of Cardiology, Clinical Cardiovascular Research Center, University of Rochester Medical Center, Rochester, NY, United States,Division of Epidemiology, Department of Public Health Sciences, University of Rochester Medical Center, Rochester, NY, United States
| | - Derick R. Peterson
- Department of Biostatistics and Computational Biology, University of Rochester Medical Center, Rochester, NY, United States
| | - Eleonora Pagan
- Department of Statistics and Quantitative Methods, University of Milan-Bicocca, Milan, Italy
| | - Vincenzo Bagnardi
- Department of Statistics and Quantitative Methods, University of Milan-Bicocca, Milan, Italy
| | - Andrea Mazzanti
- Molecular Cardiology, Istituti Clinici Scientifici Maugeri, Istituto di Ricovero e Cura a Carattere Scientifico, Pavia, Italy,Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Scott McNitt
- Division of Cardiology, Clinical Cardiovascular Research Center, University of Rochester Medical Center, Rochester, NY, United States
| | - David Q. Rich
- Division of Epidemiology, Department of Public Health Sciences, University of Rochester Medical Center, Rochester, NY, United States,Division of Pulmonary and Critical Care, Department of Medicine, University of Rochester Medical Center, Rochester, NY, United States,Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, United States
| | - Christopher L. Seplaki
- Division of Epidemiology, Department of Public Health Sciences, University of Rochester Medical Center, Rochester, NY, United States
| | - Valentina Kutyifa
- Division of Cardiology, Clinical Cardiovascular Research Center, University of Rochester Medical Center, Rochester, NY, United States
| | - Bronislava Polonsky
- Division of Cardiology, Clinical Cardiovascular Research Center, University of Rochester Medical Center, Rochester, NY, United States
| | - Alon Barsheshet
- Cardiology Division, Rabin Medical Center, Petah Tikva, Israel,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Deni Kukavica
- Molecular Cardiology, Istituti Clinici Scientifici Maugeri, Istituto di Ricovero e Cura a Carattere Scientifico, Pavia, Italy
| | - Spencer Rosero
- Division of Cardiology, University of Rochester Medical Center, Rochester, NY, United States
| | - Ilan Goldenberg
- Division of Cardiology, Clinical Cardiovascular Research Center, University of Rochester Medical Center, Rochester, NY, United States
| | - Silvia Priori
- Molecular Cardiology, Istituti Clinici Scientifici Maugeri, Istituto di Ricovero e Cura a Carattere Scientifico, Pavia, Italy,Department of Molecular Medicine, University of Pavia, Pavia, Italy,Molecular Cardiology, Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Wojciech Zareba
- Division of Cardiology, Clinical Cardiovascular Research Center, University of Rochester Medical Center, Rochester, NY, United States,*Correspondence: Wojciech Zareba,
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Rucinski C, Yunis LK, Rosas F, Santacruz D, Camargo JM, Yunis JJ. Genetic variants in Colombian patients with inherited cardiac conditions. Mol Genet Genomic Med 2022; 10:e2046. [PMID: 36204818 PMCID: PMC9651603 DOI: 10.1002/mgg3.2046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 08/07/2022] [Accepted: 08/09/2022] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Clinical and molecular diagnosis of inherited cardiac conditions is key to find at-risk subjects and avoid preventable deaths. This study aimed to identify genetic variants in a sample of Colombian patients diagnosed with inherited cardiac conditions. METHODS Next-generation sequencing (Illumina platform) using a 231 gene panel was performed in blood samples of 25 unrelated patients with age disease onset between 9 and 55 years. RESULTS Genetic testing yield was 52%. Two novel likely pathogenic/ pathogenic variants were found: a DSP nonsense variant in a patient with arrhythmogenic cardiomyopathy and a KCNE1 frameshift variant in two patients with long QT syndrome. Younger individuals (<18 years) had the highest genetic testing yield (66.6%) compared to 50% and 20% in young adults and patients over 40 years, respectively. All subjects affected with long QT syndrome with a severe event while exercising had a positive genetic test. They also had four times more loss of consciousness events and, resuscitated sudden cardiac arrest was more representative. CONCLUSION This study is the first one undertaken in Colombia to evaluate inherited cardiac conditions. It highlights the need to perform mutational analysis to provide adequate genetic counseling and to be able to identify patients at risk of severe events.
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Affiliation(s)
- Cynthia Rucinski
- Grupo de Patología Molecular, Facultad de Medicina e Instituto de GenéticaUniversidad Nacional de ColombiaBogotáColombia
| | - Luz Karime Yunis
- Grupo de Patología Molecular, Facultad de Medicina e Instituto de GenéticaUniversidad Nacional de ColombiaBogotáColombia,Servicios Médico Yunis Turbay y Cia, SASBogotáColombia
| | | | | | | | - Juan José Yunis
- Grupo de Patología Molecular, Facultad de Medicina e Instituto de GenéticaUniversidad Nacional de ColombiaBogotáColombia,Servicios Médico Yunis Turbay y Cia, SASBogotáColombia
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vom Dahl C, Müller CE, Berisha X, Nagel G, Zimmer T. Coupling the Cardiac Voltage-Gated Sodium Channel to Channelrhodopsin-2 Generates Novel Optical Switches for Action Potential Studies. Membranes (Basel) 2022; 12:907. [PMID: 36295666 PMCID: PMC9607247 DOI: 10.3390/membranes12100907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 09/09/2022] [Accepted: 09/12/2022] [Indexed: 06/16/2023]
Abstract
Voltage-gated sodium (Na+) channels respond to short membrane depolarization with conformational changes leading to pore opening, Na+ influx, and action potential (AP) upstroke. In the present study, we coupled channelrhodopsin-2 (ChR2), the key ion channel in optogenetics, directly to the cardiac voltage-gated Na+ channel (Nav1.5). Fusion constructs were expressed in Xenopus laevis oocytes, and electrophysiological recordings were performed by the two-microelectrode technique. Heteromeric channels retained both typical Nav1.5 kinetics and light-sensitive ChR2 properties. Switching to the current-clamp mode and applying short blue-light pulses resulted either in subthreshold depolarization or in a rapid change of membrane polarity typically seen in APs of excitable cells. To study the effect of individual K+ channels on the AP shape, we co-expressed either Kv1.2 or hERG with one of the Nav1.5-ChR2 fusions. As expected, both delayed rectifier K+ channels shortened AP duration significantly. Kv1.2 currents remarkably accelerated initial repolarization, whereas hERG channel activity efficiently restored the resting membrane potential. Finally, we investigated the effect of the LQT3 deletion mutant ΔKPQ on the AP shape and noticed an extremely prolonged AP duration that was directly correlated to the size of the non-inactivating Na+ current fraction. In conclusion, coupling of ChR2 to a voltage-gated Na+ channel generates optical switches that are useful for studying the effect of individual ion channels on the AP shape. Moreover, our novel optogenetic approach provides the potential for an application in pharmacology and optogenetic tissue-engineering.
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Affiliation(s)
- Christian vom Dahl
- Institute of Physiology II, University Hospital Jena, Friedrich Schiller University, 07740 Jena, Germany
| | - Christoph Emanuel Müller
- Institute of Physiology II, University Hospital Jena, Friedrich Schiller University, 07740 Jena, Germany
| | - Xhevat Berisha
- Institute of Physiology II, University Hospital Jena, Friedrich Schiller University, 07740 Jena, Germany
| | - Georg Nagel
- Institute of Physiology—Neurophysiology, Julius Maximilians University, 97070 Wuerzburg, Germany
| | - Thomas Zimmer
- Institute of Physiology II, University Hospital Jena, Friedrich Schiller University, 07740 Jena, Germany
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Strasburger JF, Eckstein G, Butler M, Noffke P, Wacker-Gussmann A. Fetal Arrhythmia Diagnosis and Pharmacologic Management. J Clin Pharmacol 2022; 62 Suppl 1:S53-S66. [PMID: 36106782 PMCID: PMC9543141 DOI: 10.1002/jcph.2129] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 07/25/2022] [Indexed: 11/24/2022]
Abstract
One of the most successful achievements of fetal intervention is the pharmacologic management of fetal arrhythmias. This management usually takes place during the second or third trimester. While most arrhythmias in the fetus are benign, both tachy‐ and bradyarrhythmias can lead to fetal hydrops or cardiac dysfunction and require treatment under certain conditions. This review will highlight precise diagnosis by fetal echocardiography and magnetocardiography, the 2 primary means of diagnosing fetuses with arrhythmia. Additionally, transient or hidden arrhythmias such as bundle branch block, QT prolongation, and torsades de pointes, which can lead to cardiomyopathy and sudden unexplained death in the fetus, may also need pharmacologic treatment. The review will address the types of drug therapies; current knowledge of drug usage, efficacy, and precautions; and the transition to neonatal treatments when indicated. Finally, we will highlight new assessments, including the role of the nurse in the care of fetal arrhythmias. The prognosis for the human fetus with arrhythmias continues to improve as we expand our ability to provide intensive care unit–like monitoring, to better understand drug treatments, to optimize subsequent pregnancy monitoring, to effectively predict timing for delivery, and to follow up these conditions into the neonatal period and into childhood. Coordinated initiatives that facilitate clinical fetal research are needed to address gaps in knowledge and to facilitate fetal drug and device development.
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Affiliation(s)
- Janette F Strasburger
- Division of Cardiology, Departments of Pediatrics and Biomedical Engineering, Children's Wisconsin, Herma Heart Institute, and Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Gretchen Eckstein
- Division of Cardiology, Departments of Pediatrics and Biomedical Engineering, Children's Wisconsin, Herma Heart Institute, and Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Mary Butler
- College of Nursing, University of Wisconsin-Oshkosh, Oshkosh, Wisconsin, USA
| | - Patrick Noffke
- Division of Cardiology, Departments of Pediatrics and Biomedical Engineering, Children's Wisconsin, Herma Heart Institute, and Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Annette Wacker-Gussmann
- German Heart Center, Department of Congenital Heart Disease and Pediatric Cardiology Munich, Munchen, Bavaria, Germany
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Johnson AA, Crawford TR, Trudeau MC. The N-linker region of hERG1a upregulates hERG1b potassium channels. J Biol Chem 2022; 298:102233. [PMID: 35798139 PMCID: PMC9428852 DOI: 10.1016/j.jbc.2022.102233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 06/17/2022] [Accepted: 06/18/2022] [Indexed: 11/29/2022] Open
Abstract
A major physiological role of hERG1 (human Ether-á-go-go-Related Gene 1) potassium channels is to repolarize cardiac action potentials. Two isoforms, hERG1a and hERG1b, associate to form the potassium current IKr in cardiomyocytes. Inherited mutations in hERG1a or hERG1b cause prolonged cardiac repolarization, long QT syndrome, and sudden death arrhythmia. hERG1a subunits assemble with and enhance the number of hERG1b subunits at the plasma membrane, but the mechanism for the increase in hERG1b by hERG1a is not well understood. Here, we report that the hERG1a N-terminal region expressed in trans with hERG1b markedly increased hERG1b currents and increased biotin-labeled hERG1b protein at the membrane surface. hERG1b channels with a deletion of the N-terminal 1b domain did not have a measurable increase in current or biotinylated protein when coexpressed with hERG1a N-terminal regions, indicating that the 1b domain was required for the increase in hERG1b. Using a biochemical pull-down interaction assay and a FRET hybridization experiment, we detected a direct interaction between the hERG1a N-terminal region and the hERG1b N-terminal region. Using engineered deletions and alanine mutagenesis, we identified a short span of amino acids at positions 216 to 220 within the hERG1a "N-linker" region that were necessary for the upregulation of hERG1b. We propose that direct structural interactions between the hERG1a N-linker region and the hERG1b 1b domain increase hERG1b at the plasma membrane. Mechanisms regulating hERG1a and hERG1b are likely critical for cardiac function, may be disrupted by long QT syndrome mutants, and serve as potential targets for therapeutics.
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Affiliation(s)
- Ashley A Johnson
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Taylor R Crawford
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Matthew C Trudeau
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, USA.
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Abstract
Background Fetal echocardiography has been the mainstay of fetal arrhythmia diagnosis; however, fetal magnetocardiography (fMCG) has recently become clinically available. We sought to determine to what extent fMCG contributed to the precision and accuracy of fetal arrhythmia diagnosis and risk assessment, and in turn, how this altered pregnancy management. Methods and Results We reviewed fMCG tracings and medical records of 215 pregnancies referred to the Biomagnetism Laboratory, UW‐Madison, over the last 10 years, because of fetal arrhythmia or risk of arrhythmia. We compared referral diagnosis and treatment with fMCG diagnosis using a rating scale and restricted our review to the 144 subjects from the tachycardia, bradycardia/AV block, and familial long QT syndrome categories. Additional fMCG findings beyond those of the referring echocardiogram, or an alternative diagnosis were seen in 117/144 (81%), and 81 (56%) were critical changes. Eight (5.5%) had resolution of arrhythmia before fMCG. At least moderate changes in management were seen in 109/144 (76%) fetuses, of which 35/144 (24%) were major. The most diverse fMCG presentation was long QT syndrome, present in all 3 referral categories. Four of 5 stillbirths were seen with long QT syndrome. Nine fetuses showed torsades de pointes ventricular tachycardia, of which only 2 were recognized before fMCG. Conclusions FMCG has a significant impact on prenatal diagnosis and management of arrhythmias or familial arrhythmia risk, which cannot be fully met by existing technology. The combination of fMCG and fetal echocardiography in fetal care centers will be needed in the future to optimize care.
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Affiliation(s)
- Annette Wacker-Gussmann
- Department of Congential Heart Disease and Pediatric Cardiology German Heart Center Munich Germany
| | - Janette F Strasburger
- Departments of Pediatrics and Biomedical Engineering Children's Wisconsin and Herma Heart Institute Milwaukee WI
| | - Ronald T Wakai
- Department of Medical Physics University of Wisconsin-Madison Madison WI
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Fowler ED, Zissimopoulos S. Molecular, Subcellular, and Arrhythmogenic Mechanisms in Genetic RyR2 Disease. Biomolecules 2022; 12:1030. [PMID: 35892340 DOI: 10.3390/biom12081030] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 07/22/2022] [Accepted: 07/24/2022] [Indexed: 11/17/2022] Open
Abstract
The ryanodine receptor (RyR2) has a critical role in controlling Ca2+ release from the sarcoplasmic reticulum (SR) throughout the cardiac cycle. RyR2 protein has multiple functional domains with specific roles, and four of these RyR2 protomers are required to form the quaternary structure that comprises the functional channel. Numerous mutations in the gene encoding RyR2 protein have been identified and many are linked to a wide spectrum of arrhythmic heart disease. Gain of function mutations (GoF) result in a hyperactive channel that causes excessive spontaneous SR Ca2+ release. This is the predominant cause of the inherited syndrome catecholaminergic polymorphic ventricular tachycardia (CPVT). Recently, rare hypoactive loss of function (LoF) mutations have been identified that produce atypical effects on cardiac Ca2+ handling that has been termed calcium release deficiency syndrome (CRDS). Aberrant Ca2+ release resulting from both GoF and LoF mutations can result in arrhythmias through the Na+/Ca2+ exchange mechanism. This mini-review discusses recent findings regarding the role of RyR2 domains and endogenous regulators that influence RyR2 gating normally and with GoF/LoF mutations. The arrhythmogenic consequences of GoF/LoF mutations will then be discussed at the macromolecular and cellular level.
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Chen L, Peng G, Comollo TW, Zou X, Sampson KJ, Larsson HP, Kass RS. Two small-molecule activators share similar effector sites in the KCNQ1 channel pore but have distinct effects on voltage sensor movements. Front Physiol 2022; 13:903050. [PMID: 35957984 PMCID: PMC9359618 DOI: 10.3389/fphys.2022.903050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 06/30/2022] [Indexed: 11/13/2022] Open
Abstract
ML277 and R-L3 are two small-molecule activators of KCNQ1, the pore-forming subunit of the slowly activating potassium channel IKs. KCNQ1 loss-of-function mutations prolong cardiac action potential duration and are associated with long QT syndrome, which predispose patients to lethal ventricular arrhythmia. ML277 and R-L3 enhance KCNQ1 current amplitude and slow deactivation. However, the presence of KCNE1, an auxiliary subunit of IKs channels, renders the channel insensitive to both activators. We found that ML277 effects are dependent on several residues in the KCNQ1 pore domain. Some of these residues are also necessary for R-L3 effects. These residues form a putative hydrophobic pocket located between two adjacent KCNQ1 subunits, where KCNE1 subunits are thought to dwell, thus providing an explanation for how KCNE1 renders the IKs channel insensitive to these activators. Our experiments showed that the effect of R-L3 on voltage sensor movement during channel deactivation was much more prominent than that of ML277. Simulations using a KCNQ1 kinetic model showed that the effects of ML277 and R-L3 could be reproduced through two different effects on channel gating: ML277 enhances KCNQ1 channel function through a pore-dependent and voltage sensor-independent mechanism, while R-L3 affects both channel pore and voltage sensor.
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Affiliation(s)
- Lei Chen
- Department of Molecular Pharmacology and Therapeutics, Vagelos College of Physicians & Surgeons of Columbia University Irving Medical Center, New York, NY, United States
| | - Gary Peng
- Department of Molecular Pharmacology and Therapeutics, Vagelos College of Physicians & Surgeons of Columbia University Irving Medical Center, New York, NY, United States
| | - Thomas W. Comollo
- Department of Molecular Pharmacology and Therapeutics, Vagelos College of Physicians & Surgeons of Columbia University Irving Medical Center, New York, NY, United States
| | - Xinle Zou
- Department of Molecular Pharmacology and Therapeutics, Vagelos College of Physicians & Surgeons of Columbia University Irving Medical Center, New York, NY, United States
| | - Kevin J. Sampson
- Department of Molecular Pharmacology and Therapeutics, Vagelos College of Physicians & Surgeons of Columbia University Irving Medical Center, New York, NY, United States
| | - H. Peter Larsson
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, Miami, FL, United States
| | - Robert S. Kass
- Department of Molecular Pharmacology and Therapeutics, Vagelos College of Physicians & Surgeons of Columbia University Irving Medical Center, New York, NY, United States,*Correspondence: Robert S. Kass,
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Yang Y, Lv T, Li S, Liu P, Gao Q, Zhang P. Utility of Provocative Testing in the Diagnosis and Genotyping of Congenital Long QT Syndrome: A Systematic Review and Meta-Analysis. J Am Heart Assoc 2022; 11:e025246. [PMID: 35861842 PMCID: PMC9707831 DOI: 10.1161/jaha.122.025246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Accepted: 04/27/2022] [Indexed: 11/16/2022]
Abstract
Background Diagnosis is particularly challenging in concealed or asymptomatic long QT syndrome (LQTS). Provocative testing, unmasking the characterization of LQTS, is a promising alternative method for the diagnosis of LQTS, but without uniform standards. Methods and Results A comprehensive search was conducted in PubMed, Embase, and the Cochrane Library through October 14, 2021. The fixed effects model was used to assess the effect of the provocative testing on QTc interval. A total of 22 studies with 1137 patients with LQTS were included. At baseline, QTc interval was 40 ms longer in patients with LQTS than in controls (mean difference [MD], 40.54 [95% CI, 37.43-43.65]; P<0.001). Compared with the control group, patients with LQTS had 28 ms longer ΔQTc upon standing (MD, 28.82 [95% CI, 23.05-34.58]; P<0.001), nearly 30 ms longer both at peak exercise (MD, 27.31 [95% CI, 21.51-33.11]; P<0.001) and recovery 4 to 5 minutes (MD, 29.85 [95% CI, 24.36-35.35]; P<0.001). With epinephrine infusion, QTc interval was prolonged both in controls and patients with QTS, most obviously in LQT1 (MD, 68.26 [95% CI, 58.91-77.60]; P<0.001) and LQT2 (MD, 60.17 [95% CI, 50.18-70.16]; P<0.001). Subgroup analysis showed QTc interval response to abrupt stand testing and exercise testing varied between LQT1, LQT2, and LQT3, named Type Ⅰ, Type Ⅱ, and Type Ⅲ. Conclusions QTc trend Type Ⅰ and Type Ⅲ during abrupt stand testing and exercise testing can be used to propose a prospective evaluation of LQT1 and LQT3, respectively. Type Ⅱ QTc trend combined epinephrine infusion testing could distinguish LQT2 from control. A preliminary diagnostic workflow was proposed but deserves further evaluation.
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Affiliation(s)
- Ying Yang
- School of Clinical MedicineTsinghua UniversityBeijingChina
| | - Ting‐ting Lv
- Department of CardiologySchool of Clinical MedicineBeijing Tsinghua Changgung HospitalTsinghua UniversityBeijingChina
| | - Si‐yuan Li
- Department of CardiologySchool of Clinical MedicineBeijing Tsinghua Changgung HospitalTsinghua UniversityBeijingChina
| | - Peng Liu
- School of Clinical MedicineTsinghua UniversityBeijingChina
| | - Qing‐gele Gao
- School of Clinical MedicineTsinghua UniversityBeijingChina
| | - Ping Zhang
- School of Clinical MedicineTsinghua UniversityBeijingChina
- Department of CardiologySchool of Clinical MedicineBeijing Tsinghua Changgung HospitalTsinghua UniversityBeijingChina
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73
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Jiang C, Richardson E, Farr J, Hill AP, Ullah R, Kroncke BM, Harrison SM, Thomson KL, Ingles J, Vandenberg JI, Ng CA. A calibrated functional patch-clamp assay to enhance clinical variant interpretation in KCNH2-related long QT syndrome. Am J Hum Genet 2022; 109:1199-1207. [PMID: 35688147 PMCID: PMC9300752 DOI: 10.1016/j.ajhg.2022.05.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 05/03/2022] [Indexed: 01/09/2023] Open
Abstract
Modern sequencing technologies have revolutionized our detection of gene variants. However, in most genes, including KCNH2, the majority of missense variants are currently classified as variants of uncertain significance (VUSs). The aim of this study was to investigate the utility of an automated patch-clamp assay for aiding clinical variant classification in KCNH2. The assay was designed according to recommendations proposed by the Clinical Genome Sequence Variant Interpretation Working Group. Thirty-one variants (17 pathogenic/likely pathogenic, 14 benign/likely benign) were classified internally as variant controls. They were heterozygously expressed in Flp-In HEK293 cells for assessing the effects of variants on current density and channel gating in order to determine the sensitivity and specificity of the assay. All 17 pathogenic variant controls had reduced current density, and 13 of 14 benign variant controls had normal current density, which enabled determination of normal and abnormal ranges for applying evidence of moderate or supporting strength for VUS reclassification. Inclusion of functional assay evidence enabled us to reclassify 6 out of 44 KCNH2 VUSs as likely pathogenic. The high-throughput patch-clamp assay can provide moderate-strength evidence for clinical interpretation of clinical KCNH2 variants and demonstrates the value of developing automated patch-clamp assays for functional characterization of ion channel gene variants.
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Affiliation(s)
- Connie Jiang
- Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; Faculty of Medicine and Health, UNSW Sydney, Kensington, NSW, Australia
| | - Ebony Richardson
- Centre for Population Genomics, Garvan Institute of Medical Research and UNSW Sydney, Sydney, Australia; Centre for Population Genomics, Murdoch Children's Research Institute, Melbourne, Australia
| | - Jessica Farr
- Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; School of Computer Science and Engineering, UNSW Sydney, Kensington, NSW, Australia
| | - Adam P Hill
- Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; School of Clinical Medicine, UNSW Sydney, Darlinghurst, NSW, Australia
| | - Rizwan Ullah
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Brett M Kroncke
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | | | - Kate L Thomson
- Oxford Medical Genetics Laboratories, Churchill Hospital, Oxford, UK
| | - Jodie Ingles
- Centre for Population Genomics, Garvan Institute of Medical Research and UNSW Sydney, Sydney, Australia; Centre for Population Genomics, Murdoch Children's Research Institute, Melbourne, Australia
| | - Jamie I Vandenberg
- Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; School of Clinical Medicine, UNSW Sydney, Darlinghurst, NSW, Australia.
| | - Chai-Ann Ng
- Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; School of Clinical Medicine, UNSW Sydney, Darlinghurst, NSW, Australia.
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Ng CA, Ullah R, Farr J, Hill AP, Kozek KA, Vanags LR, Mitchell DW, Kroncke BM, Vandenberg JI. A massively parallel assay accurately discriminates between functionally normal and abnormal variants in a hotspot domain of KCNH2. Am J Hum Genet 2022; 109:1208-1216. [PMID: 35688148 PMCID: PMC9300756 DOI: 10.1016/j.ajhg.2022.05.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 05/03/2022] [Indexed: 01/09/2023] Open
Abstract
Many genes, including KCNH2, contain "hotspot" domains associated with a high density of variants associated with disease. This has led to the suggestion that variant location can be used as evidence supporting classification of clinical variants. However, it is not known what proportion of all potential variants in hotspot domains cause loss of function. Here, we have used a massively parallel trafficking assay to characterize all single-nucleotide variants in exon 2 of KCNH2, a known hotspot for variants that cause long QT syndrome type 2 and an increased risk of sudden cardiac death. Forty-two percent of KCNH2 exon 2 variants caused at least 50% reduction in protein trafficking, and 65% of these trafficking-defective variants exerted a dominant-negative effect when co-expressed with a WT KCNH2 allele as assessed using a calibrated patch-clamp electrophysiology assay. The massively parallel trafficking assay was more accurate (AUC of 0.94) than bioinformatic prediction tools (REVEL and CardioBoost, AUC of 0.81) in discriminating between functionally normal and abnormal variants. Interestingly, over half of variants in exon 2 were found to be functionally normal, suggesting a nuanced interpretation of variants in this "hotspot" domain is necessary. Our massively parallel trafficking assay can provide this information prospectively.
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Affiliation(s)
- Chai-Ann Ng
- Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; School of Clinical Medicine, UNSW Sydney, Darlinghurst, NSW, Australia
| | - Rizwan Ullah
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Jessica Farr
- Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; School of Computer Science and Engineering, UNSW Sydney, Kensington, NSW, Australia
| | - Adam P Hill
- Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; School of Clinical Medicine, UNSW Sydney, Darlinghurst, NSW, Australia
| | - Krystian A Kozek
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Loren R Vanags
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Devyn W Mitchell
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Brett M Kroncke
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
| | - Jamie I Vandenberg
- Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; School of Clinical Medicine, UNSW Sydney, Darlinghurst, NSW, Australia.
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75
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Kekenes-Huskey PM, Burgess DE, Sun B, Bartos DC, Rozmus ER, Anderson CL, January CT, Eckhardt LL, Delisle BP. Mutation-Specific Differences in Kv7.1 ( KCNQ1) and Kv11.1 ( KCNH2) Channel Dysfunction and Long QT Syndrome Phenotypes. Int J Mol Sci 2022; 23:7389. [PMID: 35806392 PMCID: PMC9266926 DOI: 10.3390/ijms23137389] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Revised: 06/22/2022] [Accepted: 06/24/2022] [Indexed: 11/16/2022] Open
Abstract
The electrocardiogram (ECG) empowered clinician scientists to measure the electrical activity of the heart noninvasively to identify arrhythmias and heart disease. Shortly after the standardization of the 12-lead ECG for the diagnosis of heart disease, several families with autosomal recessive (Jervell and Lange-Nielsen Syndrome) and dominant (Romano-Ward Syndrome) forms of long QT syndrome (LQTS) were identified. An abnormally long heart rate-corrected QT-interval was established as a biomarker for the risk of sudden cardiac death. Since then, the International LQTS Registry was established; a phenotypic scoring system to identify LQTS patients was developed; the major genes that associate with typical forms of LQTS were identified; and guidelines for the successful management of patients advanced. In this review, we discuss the molecular and cellular mechanisms for LQTS associated with missense variants in KCNQ1 (LQT1) and KCNH2 (LQT2). We move beyond the "benign" to a "pathogenic" binary classification scheme for different KCNQ1 and KCNH2 missense variants and discuss gene- and mutation-specific differences in K+ channel dysfunction, which can predispose people to distinct clinical phenotypes (e.g., concealed, pleiotropic, severe, etc.). We conclude by discussing the emerging computational structural modeling strategies that will distinguish between dysfunctional subtypes of KCNQ1 and KCNH2 variants, with the goal of realizing a layered precision medicine approach focused on individuals.
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Affiliation(s)
- Peter M. Kekenes-Huskey
- Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA
| | - Don E. Burgess
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536, USA; (D.E.B.); (E.R.R.)
| | - Bin Sun
- Department of Pharmacology, Harbin Medical University, Harbin 150081, China;
| | | | - Ezekiel R. Rozmus
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536, USA; (D.E.B.); (E.R.R.)
| | - Corey L. Anderson
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI 53705, USA; (C.L.A.); (C.T.J.); (L.L.E.)
| | - Craig T. January
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI 53705, USA; (C.L.A.); (C.T.J.); (L.L.E.)
| | - Lee L. Eckhardt
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI 53705, USA; (C.L.A.); (C.T.J.); (L.L.E.)
| | - Brian P. Delisle
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536, USA; (D.E.B.); (E.R.R.)
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76
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Al Salmani MK, Tavakoli R, Zaman W, Al Harrasi A. Multiple mechanisms underlie reduced potassium conductance in the p.T1019PfsX38 variant of hERG. Physiol Rep 2022; 10:e15341. [PMID: 35854468 PMCID: PMC9296870 DOI: 10.14814/phy2.15341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 05/15/2022] [Accepted: 05/16/2022] [Indexed: 11/30/2022] Open
Abstract
Long QT syndrome type II (LQT2) is caused by loss‐of‐function mutations in the hERG K+ channel, leading to increased incidence of cardiac arrest and sudden death. Many genetic variants have been reported in the hERG gene with various consequences on channel expression, permeation, and gating. Only a small number of LQT2 causing variants has been characterized to define the underlying pathophysiological causes of the disease. We sought to determine the characteristics of the frameshift variant p.Thr1019ProfsX38 (T1019PfsX38) which affects the C‐terminus of the protein. This mutation was identified in an extended Omani family of LQT2. It replaces the last 140 amino acids of hERG with 37 unique amino acids. T1019 is positioned at a distinguished region of the C‐terminal tail of hERG, as predicted from the deep learning system AlphaFold v2.0. We employed the whole‐cell configuration of the patch‐clamp technique to study wild‐type and mutant channels that were transiently expressed in human embryonic kidney 293 (HEK293) cells. Depolarizing voltages elicited slowly deactivating tail currents that appeared upon repolarization of cells that express either wild‐type‐ or T1019PfsX38‐hERG. There were no differences in the voltage and time dependencies of activation between the two variants. However, the rates of hERG channel deactivation at hyperpolarizing potentials were accelerated by T1019PfsX38. In addition, the voltage dependence of inactivation of T1019PfsX38‐hERG was shifted by 20 mV in the negative direction when compared with wild‐type hERG. The rates of channel inactivation were increased in the mutant channel variant. Next, we employed a step‐ramp protocol to mimic membrane repolarization by the cardiac action potential. The amplitudes of outward currents and their integrals were reduced in the mutant variant when compared with the wild‐type variant during repolarization. Thus, changes in the gating dynamics of hERG by the T1019PfsX38 variant contribute to the pathology seen in affected LQT2 patients.
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Affiliation(s)
- Majid K Al Salmani
- Natural and Medical Sciences Research Center, University of Nizwa, Nizwa, Oman
| | - Rezvan Tavakoli
- Natural and Medical Sciences Research Center, University of Nizwa, Nizwa, Oman
| | - Wajid Zaman
- Natural and Medical Sciences Research Center, University of Nizwa, Nizwa, Oman
| | - Ahmed Al Harrasi
- Natural and Medical Sciences Research Center, University of Nizwa, Nizwa, Oman
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77
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Hsu YT, Lee PC, Chen YH, Yeh SJ, Chen MR, Hsu KH, Chang CI, Lai WT, Hung WL. Resuscitated Sudden Cardiac Arrest of a Neonate with Congenital LQT Syndrome-Associated Torsades de Pointes: A Case Report and Literature Review. J Cardiovasc Dev Dis 2022; 9:jcdd9060184. [PMID: 35735813 PMCID: PMC9225216 DOI: 10.3390/jcdd9060184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 05/30/2022] [Accepted: 06/07/2022] [Indexed: 11/25/2022] Open
Abstract
Sudden infant death syndrome (SIDS), the most common cause of infant death in developed countries, is attributed to diverse trigger factors. Malignant cardiac dysrhythmias are potentially treatable etiologies, and congenital long QT syndrome (LQTS) is the most common cardiac ionic channelopathy confronted. β-Blockers or class Ib agents are the drugs of choice for the control of arrhythmias, and an implantable cardioverter defibrillator (ICD) should be considered for secondary prevention in survivors of lethal cardiac death. We report the case of a 4-day old neonate, later genetically confirmed as LQT type 3 (LQT3), who survived a pulseless torsades de pointes (TdP) attack and was successfully treated with propranolol, mexiletine, and ICD implantation.
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Affiliation(s)
- Yen-Teng Hsu
- Department of Pediatric Cardiology, Mackay Children’s Hospital, Taipei 104217, Taiwan; (Y.-T.H.); (Y.-H.C.); (S.-J.Y.); (M.-R.C.)
| | - Pi-Chang Lee
- Department of Medical Education, Taichung Veterans General Hospital, Taichung 40705, Taiwan;
| | - Yu-Hsuan Chen
- Department of Pediatric Cardiology, Mackay Children’s Hospital, Taipei 104217, Taiwan; (Y.-T.H.); (Y.-H.C.); (S.-J.Y.); (M.-R.C.)
| | - Shu-Jen Yeh
- Department of Pediatric Cardiology, Mackay Children’s Hospital, Taipei 104217, Taiwan; (Y.-T.H.); (Y.-H.C.); (S.-J.Y.); (M.-R.C.)
| | - Ming-Ren Chen
- Department of Pediatric Cardiology, Mackay Children’s Hospital, Taipei 104217, Taiwan; (Y.-T.H.); (Y.-H.C.); (S.-J.Y.); (M.-R.C.)
| | - Kung-Hong Hsu
- Department of Surgery, Division of Cardiovascular Surgery, Mackay Memorial Hospital, Taipei 104217, Taiwan; (K.-H.H.); (C.-I.C.)
| | - Chung-I Chang
- Department of Surgery, Division of Cardiovascular Surgery, Mackay Memorial Hospital, Taipei 104217, Taiwan; (K.-H.H.); (C.-I.C.)
| | - Wei-Ting Lai
- Department of Pediatrics, Division of Pediatric Cardiology, Hung Chi Women and Children’s Hospital, Taoyuan 320675, Taiwan;
| | - Wei-Li Hung
- Department of Pediatric Cardiology, Mackay Children’s Hospital, Taipei 104217, Taiwan; (Y.-T.H.); (Y.-H.C.); (S.-J.Y.); (M.-R.C.)
- Correspondence: ; Tel.: +886-2-2543-3535
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78
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Gallo T, Heise CW, Woosley RL, Tisdale JE, Tan MS, Gephart SM, Antonescu CC, Malone DC. Clinician Responses to a Clinical Decision Support Advisory for High Risk of Torsades de Pointes. J Am Heart Assoc 2022; 11:e024338. [PMID: 35656987 PMCID: PMC9238706 DOI: 10.1161/jaha.122.024338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Torsade de pointes (TdP) is a potentially fatal cardiac arrhythmia that is often drug induced. Clinical decision support (CDS) may help minimize TdP risk by guiding decision making in patients at risk. CDS has been shown to decrease prescribing of high‐risk medications in patients at risk of TdP, but alerts are often ignored. Other risk‐management options can potentially be incorporated in TdP risk CDS. Our goal was to evaluate actions clinicians take in response to a CDS advisory that uses a modified Tisdale QT risk score and presents management options that are easily selected (eg, single click). Methods and Results We implemented an inpatient TdP risk advisory systemwide across a large health care system comprising 30 hospitals. This CDS was programmed to appear when prescribers attempted ordering medications with a known risk of TdP in a patient with a QT risk score ≥12. The CDS displayed patient‐specific information and offered relevant management options including canceling offending medications and ordering electrolyte replacement protocols or ECGs. We retrospectively studied the actions clinicians took within the advisory and separated by drug class. During an 8‐month period, 7794 TdP risk advisories were issued. Antibiotics were the most frequent trigger of the advisory (n=2578, 33.1%). At least 1 action was taken within the advisory window for 2700 (34.6%) of the advisories. The most frequent action taken was ordering an ECG (n=1584, 20.3%). Incoming medication orders were canceled in 793 (10.2%) of the advisories. The frequency of each action taken varied by drug class (P<0.05 for all actions). Conclusions A modified Tisdale QT risk score–based CDS that offered relevant single‐click management options yielded a high action/response rate. Actions taken by clinicians varied depending on the class of the medication that evoked the TdP risk advisory, but the most frequent was ordering an ECG.
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Affiliation(s)
- Tyler Gallo
- Division of Clinical Data Analytics and Decision Support University of Arizona College of Medicine-Phoenix AZ.,Department of Pharmacy Practice and Science University of Arizona College of Pharmacy Phoenix AZ
| | - C William Heise
- Division of Clinical Data Analytics and Decision Support University of Arizona College of Medicine-Phoenix AZ.,Department of Medical Toxicology Banner-University Medical Center Phoenix Phoenix AZ
| | - Raymond L Woosley
- Division of Clinical Data Analytics and Decision Support University of Arizona College of Medicine-Phoenix AZ.,Arizona Center for Education and Research on Therapeutics Oro Valley AZ
| | - James E Tisdale
- Department of Pharmacy Practice College of Pharmacy Purdue University Indianapolis IN.,Division of Clinical Pharmacology School of Medicine Indiana University Indianapolis IN
| | - Malinda S Tan
- College of Pharmacy University of Utah Salt Lake City UT
| | - Sheila M Gephart
- Community and Health Systems Science Division College of Nursing University of Arizona Tucson AZ
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79
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Rosamilia MB, Lu IM, Landstrom AP. Pathogenicity Assignment of Variants in Genes Associated With Cardiac Channelopathies Evolve Toward Diagnostic Uncertainty. Circ Genom Precis Med 2022; 15:e003491. [PMID: 35543671 DOI: 10.1161/circgen.121.003491] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Accurately determining variant pathogenicity is critical in the diagnosis of cardiac channelopathies; however, it remains unknown how variant pathogenicity status changes over time. Our aim is to use a comprehensive analysis of ClinVar to understand the mutability of variant evaluation in channelopathy-associated genes to inform clinical decision-making around variant calling. METHODS We identified 10 genes (RYR2, CASQ2, KCNQ1, KCNH2, SCN5A, CACNA1C, CALM1, CALM2, CALM3, TRDN) strongly associated with cardiac channelopathies, as well as 3 comparison gene sets (disputed long QT syndrome, sudden unexpected death in epilepsy, and all ClinVar). We comprehensively analyzed variant pathogenicity calls over time using the ClinVar database with Rstudio. Analyses focused on the frequency and directionality of clinically meaningful changes in disease association, defined as a change from one of the following three categories to another: likely benign/benign, conflicting evidence of pathogenicity/variant of uncertain significance, and likely pathogenic/pathogenic. RESULTS In total, among channelopathy-associated genes, there were 9975 variants in ClinVar and 8.4% had a clinically meaningful change in disease association at least once over the past 10 years, as opposed to 4.9% of all ClinVar variants. The 3 channelopathy-associated genes with the most variants undergoing a clinically significant change were KCNQ1 (20.9%), SCN5A (11.2%), and KCNH2 (10.1%). Ten of the 12 included genes had variant evaluations that trended toward diagnostic uncertainty over time. Specifically, channelopathy-associated gene variants with either pathogenic/likely pathogenic or benign/likely benign assignments were 5.6× and 2×, respectively, as likely to be reevaluated to conflicting/variant of uncertain significance compared to the converse. CONCLUSIONS Over the past 10 years, 8.4% of variants in channelopathy-associated genes have changed pathogenicity status with a decline in overall diagnostic certainty. Ongoing clinical and genetic variant follow-up is needed to account for presence of clinically meaningful change in variant pathogenicity assignment over time.
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Affiliation(s)
- Michael B Rosamilia
- Division of Pediatric Cardiology, Department of Pediatrics (M.B.R., I.M.L., A.P.L.), Duke University School of Medicine, Durham, NC
| | - Isa M Lu
- Division of Pediatric Cardiology, Department of Pediatrics (M.B.R., I.M.L., A.P.L.), Duke University School of Medicine, Durham, NC
| | - Andrew P Landstrom
- Division of Pediatric Cardiology, Department of Pediatrics (M.B.R., I.M.L., A.P.L.), Duke University School of Medicine, Durham, NC.,Department of Cell Biology (A.P.L.), Duke University School of Medicine, Durham, NC
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80
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Waddell-Smith KE, Chaptynova AA, Li J, Crawford JR, Hinds H, Skinner JR. Holter Recordings at Initial Assessment for Long QT Syndrome: Relationship to Genotype Status and Cardiac Events. J Cardiovasc Dev Dis 2022; 9. [PMID: 35621875 DOI: 10.3390/jcdd9050164] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 05/19/2022] [Accepted: 05/20/2022] [Indexed: 11/17/2022] Open
Abstract
Background: The relationship of Holter recordings of repolarization length to outcome in long QT syndrome (LQTS) is unknown. Methods: Holter recordings and initial 12 lead ECG QTc were related to outcome in 101 individuals with LQTS and 28 gene-negative relatives. Mean QTc (mQTc) and mean RTPc (R-wave to peak T-wave, mRTPc) using Bazett correction were measured, analyzing heart rates 40 to 120 bpm. Previously reported upper limit of normal (ULN) were: women and children (<15 years), mQTc 454, mRTPc 318 ms; men mQTc 446 ms, mRTPc 314 ms. Results: Measurements in LQTS patients were greatly prolonged; children and women mean mQTc 482 ms (range 406−558), mRTPc 351 ms (259−443); males > 15 years mQTc 469 ms (407−531), mRTPc 338 ms (288−388). Ten patients had cardiac arrest (CA), and 24 had arrhythmic syncope before or after the Holter. Holter values were more closely related to genotype status and symptoms than 12 lead QTc, e.g., sensitivity/specificity for genotype positive status, mRTPc > ULN (89%/86%); CA, mRTPc > 30 ms over ULN (48%/100%). Of 34 symptomatic (CA/syncope) patients, only 9 (26%) had 12 lead QTc > 500 ms, whereas 33/34 (94%) had an mRTPc or mQTc above ULN. In 10 with CA, all Holter measurements were > 15 ms above ULN, but only two had 12 lead QTc > 500 m. Conclusions: Holter average repolarization length, particularly mRTPc, reflects definite LQTS status and clinical risk better than the initial 12 lead QTc. Values below ULN indicate both a low risk of having LQTS and a low risk of cardiac events in the small percentage that do.
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Nauffal V, Morrill VN, Jurgens SJ, Choi SH, Hall AW, Weng LC, Halford JL, Austin-Tse C, Haggerty CM, Harris SL, Wong EK, Alonso A, Arking DE, Benjamin EJ, Boerwinkle E, Min YI, Correa A, Fornwalt BK, Heckbert SR, Kooperberg C, Lin HJ, J F Loos R, Rice KM, Gupta N, Blackwell TW, Mitchell BD, Morrison AC, Psaty BM, Post WS, Redline S, Rehm HL, Rich SS, Rotter JI, Soliman EZ, Sotoodehnia N, Lunetta KL, Ellinor PT, Lubitz SA. Monogenic and Polygenic Contributions to QTc Prolongation in the Population. Circulation 2022; 145:1524-1533. [PMID: 35389749 PMCID: PMC9117504 DOI: 10.1161/circulationaha.121.057261] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Rare sequence variation in genes underlying cardiac repolarization and common polygenic variation influence QT interval duration. However, current clinical genetic testing of individuals with unexplained QT prolongation is restricted to examination of monogenic rare variants. The recent emergence of large-scale biorepositories with sequence data enables examination of the joint contribution of rare and common variations to the QT interval in the population. METHODS We performed a genome-wide association study of the QTc in 84 630 UK Biobank participants and created a polygenic risk score (PRS). Among 26 976 participants with whole-genome sequencing and ECG data in the TOPMed (Trans-Omics for Precision Medicine) program, we identified 160 carriers of putative pathogenic rare variants in 10 genes known to be associated with the QT interval. We examined QTc associations with the PRS and with rare variants in TOPMed. RESULTS Fifty-four independent loci were identified by genome-wide association study in the UK Biobank. Twenty-one loci were novel, of which 12 were replicated in TOPMed. The PRS composed of 1 110 494 common variants was significantly associated with the QTc in TOPMed (ΔQTc/decile of PRS=1.4 ms [95% CI, 1.3 to 1.5]; P=1.1×10-196). Carriers of putative pathogenic rare variants had longer QTc than noncarriers (ΔQTc=10.9 ms [95% CI, 7.4 to 14.4]). Of individuals with QTc>480 ms, 23.7% carried either a monogenic rare variant or had a PRS in the top decile (3.4% monogenic, 21% top decile of PRS). CONCLUSIONS QTc duration in the population is influenced by both rare variants in genes underlying cardiac repolarization and polygenic risk, with a sizeable contribution from polygenic risk. Comprehensive assessment of the genetic determinants of QTc prolongation includes incorporation of both polygenic and monogenic risk.
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Affiliation(s)
- Victor Nauffal
- Division of Cardiovascular Medicine (V.N.), Brigham and Women's Hospital, Boston, MA
- Cardiovascular Disease Initiative (V.N., V.N.M., S.J.J., S.H.C., L.-C.W., J.L.H., P.T.E., S.A.L.), Broad Institute, Cambridge, MA
| | - Valerie N Morrill
- Cardiovascular Disease Initiative (V.N., V.N.M., S.J.J., S.H.C., L.-C.W., J.L.H., P.T.E., S.A.L.), Broad Institute, Cambridge, MA
| | - Sean J Jurgens
- Cardiovascular Disease Initiative (V.N., V.N.M., S.J.J., S.H.C., L.-C.W., J.L.H., P.T.E., S.A.L.), Broad Institute, Cambridge, MA
- Department of Experimental Cardiology, Amsterdam University Medical Centers, The Netherlands (S.J.J.)
- Program in Medical and Population Genetics, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge (N.G., S.J.J., S.H.C., L.C.W., J.L.H., C.A.T., H.L.R., P.T.E., S.A.L.)
| | - Seung Hoan Choi
- Cardiovascular Disease Initiative (V.N., V.N.M., S.J.J., S.H.C., L.-C.W., J.L.H., P.T.E., S.A.L.), Broad Institute, Cambridge, MA
- Program in Medical and Population Genetics, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge (N.G., S.J.J., S.H.C., L.C.W., J.L.H., C.A.T., H.L.R., P.T.E., S.A.L.)
| | - Amelia W Hall
- Gene Regulation Observatory (A.W.H.), Broad Institute, Cambridge, MA
| | - Lu-Chen Weng
- Cardiovascular Disease Initiative (V.N., V.N.M., S.J.J., S.H.C., L.-C.W., J.L.H., P.T.E., S.A.L.), Broad Institute, Cambridge, MA
- Program in Medical and Population Genetics, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge (N.G., S.J.J., S.H.C., L.C.W., J.L.H., C.A.T., H.L.R., P.T.E., S.A.L.)
| | - Jennifer L Halford
- Cardiovascular Disease Initiative (V.N., V.N.M., S.J.J., S.H.C., L.-C.W., J.L.H., P.T.E., S.A.L.), Broad Institute, Cambridge, MA
- Program in Medical and Population Genetics, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge (N.G., S.J.J., S.H.C., L.C.W., J.L.H., C.A.T., H.L.R., P.T.E., S.A.L.)
| | - Christina Austin-Tse
- Center for Genomic Medicine (C.A.-T., H.L.R.), Massachusetts General Hospital, Boston
- Program in Medical and Population Genetics, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge (N.G., S.J.J., S.H.C., L.C.W., J.L.H., C.A.T., H.L.R., P.T.E., S.A.L.)
| | - Christopher M Haggerty
- Department of Translational Data Science and Informatics, Geisinger, Danville, PA (C.M.H., B.K.F.)
| | - Stephanie L Harris
- Cardiovascular Genetics Program (S.L.H., E.K.W.), Massachusetts General Hospital, Boston
| | - Eugene K Wong
- Cardiovascular Genetics Program (S.L.H., E.K.W.), Massachusetts General Hospital, Boston
| | - Alvaro Alonso
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA (A.A.)
| | - Dan E Arking
- McKusick-Nathans Institute, Department of Genetic Medicine (D.E.A.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Emelia J Benjamin
- Boston University School of Public Health, MA (E.J.B., K.L.L.)
- Boston University School of Medicine, MA (E.J.B.)
| | - Eric Boerwinkle
- Human Genetics Center, Department of Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, University of Texas Health Science Center at Houston (E.B., A.C.M.)
| | - Yuan-I Min
- Department of Medicine, University of Mississippi Medical Center, Jackson (Y.-I.M., A.C.)
| | - Adolfo Correa
- Department of Medicine, University of Mississippi Medical Center, Jackson (Y.-I.M., A.C.)
| | - Brandon K Fornwalt
- Department of Translational Data Science and Informatics, Geisinger, Danville, PA (C.M.H., B.K.F.)
| | - Susan R Heckbert
- Cardiovascular Health Research Unit and Department of Epidemiology (S.R.H.)
| | - Charles Kooperberg
- Division of Public Health Sciences, Fred Hutchinson Cancer Center, Seattle, WA (C.K.)
| | - Henry J Lin
- Institute for Translational Genomics and Population Sciences, Department of Pediatrics, Lundquist Institute for Biomedical Innovation at Harbor-University of California-Los Angeles Medical Center, Torrance (H.J.L., J.I.R.)
| | - Ruth J F Loos
- Charles Bronfman Institute for Personalized Medicine, Icahn School of Medicine at Mount Sinai, New York (R.J.F.L.)
| | | | - Namrata Gupta
- Program in Medical and Population Genetics, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge (N.G., S.J.J., S.H.C., L.C.W., J.L.H., C.A.T., H.L.R., P.T.E., S.A.L.)
| | - Thomas W Blackwell
- Department of Biostatistics and Center for Statistical Genetics, University of Michigan, Ann Arbor (T.W.B.)
| | - Braxton D Mitchell
- Division of Endocrinology, Diabetes and Nutrition, University of Maryland School of Medicine, Baltimore (B.D.M.)
| | - Alanna C Morrison
- Human Genetics Center, Department of Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, University of Texas Health Science Center at Houston (E.B., A.C.M.)
| | - Bruce M Psaty
- Cardiovascular Health Research Unit, Departments of Medicine, Epidemiology and Health Systems and Population Health, University of Washington, Seattle, WA (B.M.P.)
| | - Wendy S Post
- Division of Cardiology, Department of Medicine (W.S.P.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Susan Redline
- Harvard Medical School (S.R.), Brigham and Women's Hospital, Boston, MA
| | - Heidi L Rehm
- Center for Genomic Medicine (C.A.-T., H.L.R.), Massachusetts General Hospital, Boston
- Program in Medical and Population Genetics, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge (N.G., S.J.J., S.H.C., L.C.W., J.L.H., C.A.T., H.L.R., P.T.E., S.A.L.)
| | - Stephen S Rich
- Center for Public Health Genomics and Department of Public Health Sciences, University of Virginia, Charlottesville (S.S.R.)
| | - Jerome I Rotter
- Institute for Translational Genomics and Population Sciences, Department of Pediatrics, Lundquist Institute for Biomedical Innovation at Harbor-University of California-Los Angeles Medical Center, Torrance (H.J.L., J.I.R.)
| | - Elsayed Z Soliman
- Epidemiological Cardiology Research Center, Wake Forest School of Medicine, Winston-Salem, NC (E.Z.S.)
| | - Nona Sotoodehnia
- Cardiovascular Health Research Unit, Departments of Medicine, Epidemiology, Cardiology, University of Washington, Seattle, WA (N.S.)
| | | | - Patrick T Ellinor
- Cardiovascular Disease Initiative (V.N., V.N.M., S.J.J., S.H.C., L.-C.W., J.L.H., P.T.E., S.A.L.), Broad Institute, Cambridge, MA
- Cardiac Arrhythmia Service and Cardiovascular Research Center (P.T.E., S.A.L.), Massachusetts General Hospital, Boston
- Program in Medical and Population Genetics, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge (N.G., S.J.J., S.H.C., L.C.W., J.L.H., C.A.T., H.L.R., P.T.E., S.A.L.)
| | - Steven A Lubitz
- Cardiovascular Disease Initiative (V.N., V.N.M., S.J.J., S.H.C., L.-C.W., J.L.H., P.T.E., S.A.L.), Broad Institute, Cambridge, MA
- Cardiac Arrhythmia Service and Cardiovascular Research Center (P.T.E., S.A.L.), Massachusetts General Hospital, Boston
- Program in Medical and Population Genetics, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge (N.G., S.J.J., S.H.C., L.C.W., J.L.H., C.A.T., H.L.R., P.T.E., S.A.L.)
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82
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Bjelic M, Zareba W, Peterson DR, Younis A, Aktas MK, Huang DT, Rosero S, Cutter K, McNitt S, Xia X, MacKecknie BD, Horn R, Sotoodehnia N, Kudenchuk PJ, Rea TD, Arking DE, Wilde AAM, Shimizu W, Ackerman MJ, Goldenberg I. Sex Hormones and Repolarization Dynamics during the Menstrual Cycle in Women with Congenital Long QT Syndrome. Heart Rhythm 2022; 19:1532-1540. [PMID: 35525425 DOI: 10.1016/j.hrthm.2022.04.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 04/25/2022] [Accepted: 04/27/2022] [Indexed: 11/17/2022]
Abstract
BACKGROUND Women with congenital long QT syndrome (LQTS) experience increased cardiac events risk after the onset of adolescence, perhaps stemming from the known modulating effects of sex hormones on the cardiac potassium channels. OBJECTIVE We hypothesized that the effect of sex hormones on cardiac ion channel function may modify ECG parameters associated with the propensity for ventricular tachyarrhythmias during the menstrual cycle in women with LQTS. METHODS We prospectively enrolled 65 women with congenital LQTS (LQT1 [N=24], LQT2 [N=20]) and unaffected female relatives [N=21]. Subjects underwent three 7-day ECG recordings during their menstrual cycles. Simultaneous saliva testing of sex hormone levels was obtained on the first day of each 7-day ECG recording cycle. RESULTS Mean age was 35±8 years, without a significant difference among the groups. In LQT2 women, linear mixed effects models showed significant inverse correlations of QTc with progesterone (p<0.001), and the progesterone to estradiol ratio (p<0.001). Inverse relationships of the RR interval with estradiol levels (p=0.003) and of the T-wave duration with testosterone levels (p=0.014) were also observed in women with LQT2. In contrast, no significant associations were observed between ECG parameters and sex hormone levels the women with LQT1 women or the unaffected relatives. CONCLUSIONS This is the first study to prospectively assess correlations between repolarization dynamics and sex hormone levels during the menstrual cycle in women with congenital LQTS. Our findings show genotype-specific unique QTc dynamics during the menstrual cycle that may affect the propensity for ventricular tachyarrhythmia in women with LQTS, particularly LQT2 women.
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Affiliation(s)
- Milica Bjelic
- Clinical Cardiovascular Research Center, Division of Cardiology, University of Rochester Medical Center, Rochester, NY, USA
| | - Wojciech Zareba
- Clinical Cardiovascular Research Center, Division of Cardiology, University of Rochester Medical Center, Rochester, NY, USA
| | - Derick R Peterson
- Department of Biostatistics and Computational Biology, University of Rochester, Rochester, NY, USA
| | - Arwa Younis
- Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - Mehmet K Aktas
- Department of Medicine, Division of Cardiology, University of Rochester Medical Center, NY, USA
| | - David T Huang
- Department of Medicine, Division of Cardiology, University of Rochester Medical Center, NY, USA
| | - Spencer Rosero
- Department of Medicine, Division of Cardiology, University of Rochester Medical Center, NY, USA
| | - Kris Cutter
- Clinical Cardiovascular Research Center, Division of Cardiology, University of Rochester Medical Center, Rochester, NY, USA
| | - Scott McNitt
- Clinical Cardiovascular Research Center, Division of Cardiology, University of Rochester Medical Center, Rochester, NY, USA
| | - Xiaojuan Xia
- Clinical Cardiovascular Research Center, Division of Cardiology, University of Rochester Medical Center, Rochester, NY, USA
| | - Bonnie D MacKecknie
- Clinical Cardiovascular Research Center, Division of Cardiology, University of Rochester Medical Center, Rochester, NY, USA
| | - Rebecca Horn
- Clinical Cardiovascular Research Center, Division of Cardiology, University of Rochester Medical Center, Rochester, NY, USA
| | - Nona Sotoodehnia
- Department of Medicine, Division of Cardiology, University of Washington, WA, USA
| | - Peter J Kudenchuk
- Department of Medicine, Division of Cardiology, University of Washington, WA, USA
| | - Thomas D Rea
- Center for Progress in Resuscitation, University of Washington, WA, USA
| | - Dan E Arking
- McKusick-Nathans Institute, Department of Genetic Medicine, John Hopkins University School of Medicine, Baltimore, MD, USA
| | - Arthur A M Wilde
- Academic Medical Center, Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centres, University of Amsterdam, Department of Clinical Cardiology, Amsterdam, the Netherlands
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
| | - Michael J Ackerman
- Departments of Cardiovascular Medicine, Pediatric and Adolescent Medicine, and Molecular Pharmacology & Experimental Therapeutics, Divisions of Heart Rhythm Services and Pediatric Cardiology, Windland Smith Rice Genetic Heart Rhythm Clinic and Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, MN, USA
| | - Ilan Goldenberg
- Clinical Cardiovascular Research Center, Division of Cardiology, University of Rochester Medical Center, Rochester, NY, USA.
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83
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Sulu A, Karacan M, Ergul Y. A very rare cause of sudden cardiac arrest in children: triadin knockout syndrome. Cardiol Young 2022; 33:1-3. [PMID: 35481495 DOI: 10.1017/s1047951122001226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Triadin knockout syndrome has been defined as a disease with transient long QT, T wave abnormalities, and extremely severe fatal cardiac arrhythmias in young children. In this report, we wanted to share the characteristics of our two cases who presented with sudden cardiac arrest and were diagnosed with triadin knockout syndrome. CASE 1 A 7.5-year-old male patient was referred to our clinic with a history of recurrent syncope and aborted cardiac arrest. There was no family history of sudden death, syncope, or arrhythmia. Physical examination, electrocardiography, echocardiography, and 24-hour rhythm Holter monitoring were normal, and bidirectional ventricular tachycardiaT was detected during the exercise stress test. Genetic analysis revealed a homozygous mutation of c.531_533delinsGG, p.(Lys179Asnfs * 44) frameshift variant in TRDN(NM_006073) gene. CASE 2 A 4.5-year-old male was admitted due to syncope during exertion and underwent cardiopulmonary resuscitation due to sudden cardiac arrest. He had family history about sudden cardiac death. Physical examination was normal, and there was borderline QTc prolongation. Bidirectional non-sustained polymorphic ventricular tachycardia was observed at adrenaline provocation test. In genetic analysis, c.568dupA, pII190Asnfs * 2 frameshift variant homozygous mutation was detected in TRDN(NM_006073) gene. Intracardiac defibrillator implantation were performed for both cases. There has not been any event under propranolol and flecainide combination treatment. CONCLUSION Triadin knockout syndrome (TCOS) is a rare overlap syndrome characterized by highly malignant arrhythmias, and it is a deadly combination of long QT syndrome and catecholaminergic polymorphic ventricular tachycardia that affects primarily young children. Since lethal arrhythmias are frequently described, genetic testing is very important in these patients. Because, identification of a genetic mutation may be a guide in treatment.
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Affiliation(s)
- Ayse Sulu
- Pediatric Cardiology, Istanbul Saglik Bilimleri University Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Education and Research Hospital, Istanbul, Turkey
| | - Mehmet Karacan
- Istanbul Saglik Bilimleri University Istanbul Umraniye Education and Research Hospital, Istanbul, Turkey
| | - Yakup Ergul
- Pediatric Cardiology, Istanbul Saglik Bilimleri University Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
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84
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Kojima K, Kato K, Fujii Y, Okuyama Y, Ohno S, Ozawa T, Horie M, Nakagawa Y. Successful Management of a Young Athlete with Type 2 Long QT Syndrome by Genotype-specific Risk Stratification and Bridging Therapy with a Wearable Cardioverter Defibrillator. Intern Med 2022; 61:1179-1182. [PMID: 35110475 PMCID: PMC9107976 DOI: 10.2169/internalmedicine.8093-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 11/25/2021] [Indexed: 11/13/2022] Open
Abstract
We herein report a 14-year-old boy with repetitive nocturnal syncope related to medication-refractory long QT syndrome (LQTS). Although the use of an implantable cardioverter-defibrillator (ICD) was inevitable to prevent sudden cardiac death, he refused immediate implantation in order to play in a baseball competition six weeks away. Given his genetic diagnosis of type 2 LQTS, which is associated with cardiac events unrelated to exercise, we prescribed a wearable cardioverter defibrillator (WCD) to be donned at night, without limiting his exercise participation. An ICD was implanted after the competition. We successfully performed the preplanned treatment while maximizing the patient's quality-of-life with a WCD and genotype-specific risk stratification.
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Affiliation(s)
- Katsumi Kojima
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Japan
| | - Koichi Kato
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Japan
| | - Yusuke Fujii
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Japan
| | - Yusuke Okuyama
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Japan
| | - Seiko Ohno
- Department of Bioscience and Genetics, National Cerebral and Cardiovascular Center, Japan
| | - Tomoya Ozawa
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Japan
| | - Minoru Horie
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Japan
| | - Yoshihisa Nakagawa
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Japan
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85
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Hodel V, Flury G. [Restlessness and Syncopes in a Patient from a Home for Elderly]. Praxis (Bern 1994) 2022; 111:283-287. [PMID: 35414251 DOI: 10.1024/1661-8157/a003834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Restlessness and Syncopes in a Patient from a Home for Elderly Abstract. A broad differential diagnosis should be considered when faced with syncopes. Most common causes are cardiovascular and neurological causes. If there is evidence of epilepsy with sudden loss of tone, look for ictal-triggered arrhythmias. Ictal bradycardias and asystoles are usually benign and self-limiting. In contrast, bradycardias and asystoles in the context of SUDEP are usually fatal and are the result of ictally induced cerebral hypoxemia.
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Affiliation(s)
- Vera Hodel
- Medizinische Klinik, Ospidal, Center da Sandà Engiadina Bassa, Scuol, Schweiz
| | - Gian Flury
- Medizinische Klinik, Ospidal, Center da Sandà Engiadina Bassa, Scuol, Schweiz
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86
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Dusi V, Pugliese L, De Ferrari GM, Odero A, Crotti L, Dagradi F, Castelletti S, Vicentini A, Rordorf R, Li C, Shkolnikova M, Spazzolini C, Schwartz PJ. Left Cardiac Sympathetic Denervation for Long QT Syndrome: 50 Years' Experience Provides Guidance for Management. JACC Clin Electrophysiol 2022; 8:281-94. [PMID: 35331422 DOI: 10.1016/j.jacep.2021.09.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/03/2021] [Accepted: 09/03/2021] [Indexed: 01/08/2023]
Abstract
OBJECTIVES This study sought to report our single-center experience with left cardiac sympathetic denervation (LCSD) for long QT syndrome (LQTS) since 1973. BACKGROUND LCSD is still underutilized because clinicians are often uncertain whether to use it versus an implantable cardioverter-defibrillator (ICD). METHODS We performed LCSD in 125 patients with LQTS (58% women, mean QT interval corrected for frequency [QTc] 527 ± 60 ms, 90% on beta blockers) with a follow-up of 12.9 ± 10.3 years. They were retrospectively divided into 4 groups according to the clinical/genetic status: very high risk (n = 18, symptomatic in the first year of life or with highly malignant genetics), with aborted cardiac arrest (ACA) (n = 31), with syncope and/or ICD shocks on beta blockers (n = 45), in primary prevention (n = 31). RESULTS After LCSD, 17% in the very high risk group remained asymptomatic, compared with 52%, 47%, and 97% in the other 3 groups (P < 0.0001), with an overall 86% decrease in the mean yearly cardiac event rate (P < 0.0001). Among 45 patients with only syncope/ICD shocks before LCSD, none had ACA/sudden death as first symptom after LCSD and a 6-month post-LCSD QTc <500 ms predicted excellent outcome. Patients with a QTc ≥500 ms have a 50% chance of shortening it by an average of 60 ms. LCSD results are not affected by common genotypes. CONCLUSIONS We provide definitive evidence for the long-term efficacy of LCSD in LQTS. The degree of antiarrhythmic protection is influenced by patient's specificity and amount of QTc shortening. This novel approach to the analysis of the outcome allows cardiologists to rationally decide and tailor their management strategies to the individual features of their patients.
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87
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Glazer AM, Davogustto G, Shaffer CM, Vanoye CG, Desai RR, Farber-Eger EH, Dikilitas O, Shang N, Pacheco JA, Yang T, Muhammad A, Mosley JD, Van Driest SL, Wells QS, Shaffer LL, Kalash OR, Wada Y, Bland S, Yoneda ZT, Mitchell DW, Kroncke BM, Kullo IJ, Jarvik GP, Gordon AS, Larson EB, Manolio TA, Mirshahi T, Luo JZ, Schaid D, Namjou B, Alsaied T, Singh R, Singhal A, Liu C, Weng C, Hripcsak G, Ralston JD, McNally EM, Chung WK, Carrell DS, Leppig KA, Hakonarson H, Sleiman P, Sohn S, Glessner J, Denny J, Wei WQ, George AL, Shoemaker MB, Roden DM. Arrhythmia Variant Associations and Reclassifications in the eMERGE-III Sequencing Study. Circulation 2022; 145:877-891. [PMID: 34930020 PMCID: PMC8940719 DOI: 10.1161/circulationaha.121.055562] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
BACKGROUND Sequencing Mendelian arrhythmia genes in individuals without an indication for arrhythmia genetic testing can identify carriers of pathogenic or likely pathogenic (P/LP) variants. However, the extent to which these variants are associated with clinically meaningful phenotypes before or after return of variant results is unclear. In addition, the majority of discovered variants are currently classified as variants of uncertain significance, limiting clinical actionability. METHODS The eMERGE-III study (Electronic Medical Records and Genomics Phase III) is a multicenter prospective cohort that included 21 846 participants without previous indication for cardiac genetic testing. Participants were sequenced for 109 Mendelian disease genes, including 10 linked to arrhythmia syndromes. Variant carriers were assessed with electronic health record-derived phenotypes and follow-up clinical examination. Selected variants of uncertain significance (n=50) were characterized in vitro with automated electrophysiology experiments in HEK293 cells. RESULTS As previously reported, 3.0% of participants had P/LP variants in the 109 genes. Herein, we report 120 participants (0.6%) with P/LP arrhythmia variants. Compared with noncarriers, arrhythmia P/LP carriers had a significantly higher burden of arrhythmia phenotypes in their electronic health records. Fifty-four participants had variant results returned. Nineteen of these 54 participants had inherited arrhythmia syndrome diagnoses (primarily long-QT syndrome), and 12 of these 19 diagnoses were made only after variant results were returned (0.05%). After in vitro functional evaluation of 50 variants of uncertain significance, we reclassified 11 variants: 3 to likely benign and 8 to P/LP. CONCLUSIONS Genome sequencing in a large population without indication for arrhythmia genetic testing identified phenotype-positive carriers of variants in congenital arrhythmia syndrome disease genes. As the genomes of large numbers of people are sequenced, the disease risk from rare variants in arrhythmia genes can be assessed by integrating genomic screening, electronic health record phenotypes, and in vitro functional studies. REGISTRATION URL: https://www. CLINICALTRIALS gov; Unique identifier; NCT03394859.
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Affiliation(s)
| | | | | | | | | | | | | | - Ning Shang
- Columbia University Irving Medical Center, New York NY
| | | | - Tao Yang
- Vanderbilt University Medical Center, Nashville TN
| | | | | | | | | | | | | | - Yuko Wada
- Vanderbilt University Medical Center, Nashville TN
| | - Sarah Bland
- Vanderbilt University Medical Center, Nashville TN
| | | | | | | | | | - Gail P. Jarvik
- Departments of Medicine (Medical Genetics) and Genome Sciences, University of Washington School of Medicine, Seattle, WA
| | | | | | | | | | | | | | - Bahram Namjou
- Cincinnati Children’s Hospital Medical Center, Cincinnati OH
| | - Tarek Alsaied
- Cincinnati Children’s Hospital Medical Center, Cincinnati OH
| | | | | | - Cong Liu
- Columbia University Irving Medical Center, New York NY
| | - Chunhua Weng
- Columbia University Irving Medical Center, New York NY
| | | | - James D. Ralston
- Departments of Medicine (Medical Genetics) and Genome Sciences, University of Washington School of Medicine, Seattle, WA
| | | | | | | | | | | | | | | | | | | | | | - Wei-Qi Wei
- Vanderbilt University Medical Center, Nashville TN
| | | | | | - Dan M. Roden
- Vanderbilt University Medical Center, Nashville TN
- Correspondence should be addressed to Dan M. Roden, MD, Vanderbilt University Medical Center, 2215B Garland Ave, 1285 MRBIV, Nashville, TN 37232,
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Kato K, Isbell HM, Fressart V, Denjoy I, Debbiche A, Itoh H, Poinsot J, George AL, Coulombe A, Shea MA, Guicheney P. Novel CALM3 Variant Causing Calmodulinopathy With Variable Expressivity in a 4-Generation Family. Circ Arrhythm Electrophysiol 2022; 15:e010572. [PMID: 35225649 DOI: 10.1161/circep.121.010572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND CaM (calmodulin), encoded by 3 separate genes (CALM1, CALM2, and CALM3), is a multifunctional Ca2+-binding protein involved in many signal transduction events including ion channel regulation. CaM variants may present with early-onset long QT syndrome (LQTS), catecholaminergic polymorphic ventricular tachycardia, or sudden cardiac death. Most reported variants occurred de novo. We identified a novel CALM3 variant, p.Asn138Lys (N138K), in a 4-generation family segregating with LQTS. The aim of this study was to elucidate its pathogenicity and to compare it with that of p.D130G-CaM-a variant associated with a severe LQTS phenotype. METHODS We performed whole exome sequencing for a large, 4-generation family affected by LQTS. To assess the effect of the detected CALM3 variant, the intrinsic Ca2+-binding affinity was measured by stoichiometric Ca2+ titrations and equilibrium titrations. L-type Ca2+ and slow delayed rectifier potassium currents (ICaL and IKs) were recorded by whole-cell patch-clamp. Cav1.2 and Kv7.1 membrane expression were determined by optical fluorescence assays. RESULTS We identified 14 p.N138K-CaM carriers in a family where 2 sudden deaths occurred in children. Several members were only mildly affected compared with CaM-LQTS patients to date described in literature. The intrinsic Ca2+-binding affinity of the CaM C-terminal domain was 10-fold lower for p.N138K-CaM compared with wild-type-CaM. ICaL inactivation was slowed in cells expressing p.N138K-CaM but less than in p.D130G-CaM cells. Unexpectedly, a larger IKs current density was observed in cells expressing p.N138K-CaM, but not for p.D130G-CaM, compared with wild-type-CaM. CONCLUSIONS The p.N138K CALM3 variant impairs Ca2+-binding affinity of CaM and ICaL inactivation but potentiates IKs. The variably expressed phenotype of this variant compared with previously published de novo LQTS-CaM variants is likely explained by a milder impairment of ICaL inactivation combined with IKs augmentation.
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Affiliation(s)
- Koichi Kato
- Sorbonne Université, Inserm, Research Unit on Cardiovascular and Metabolic Diseases, UMRS-1166, Paris, France (K.K., V.F., I.D., A.D., A.C., P.G.).,Department of Cardiovascular Medicine, Shiga University of Medical Science, Otsu, Japan (K.K.)
| | - Holly M Isbell
- Department of Biochemistry, Carver College of Medicine, University of Iowa (H.M.I., M.A.S.)
| | - Véronique Fressart
- AP-HP, Pitié-Salpêtrière Hospital, Functional Unit of Cardiogenetics and Myogenetics, Paris, France (V.F.)
| | - Isabelle Denjoy
- Sorbonne Université, Inserm, Research Unit on Cardiovascular and Metabolic Diseases, UMRS-1166, Paris, France (K.K., V.F., I.D., A.D., A.C., P.G.).,Cardiology Department, Referring Center for Heritable or Rare Cardiac Diseases, AP-HP, Bichat Hospital, HUPNVS, Referring Center for Rare Cardiac Diseases, Sorbonne University, Paris, France (I.D.)
| | - Amal Debbiche
- Sorbonne Université, Inserm, Research Unit on Cardiovascular and Metabolic Diseases, UMRS-1166, Paris, France (K.K., V.F., I.D., A.D., A.C., P.G.)
| | - Hideki Itoh
- Division of Patient Safety, Hiroshima University Hospital, Japan (H.I.)
| | - Jacques Poinsot
- Unité de cardio-pediatrie, service de medecine pediatrique, Centre Hospitalier Universitaire de Tours, Tours, France (J.P.)
| | - Alfred L George
- Department of Pharmacology Northwestern University Feinberg School of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (A.L.G.)
| | - Alain Coulombe
- Sorbonne Université, Inserm, Research Unit on Cardiovascular and Metabolic Diseases, UMRS-1166, Paris, France (K.K., V.F., I.D., A.D., A.C., P.G.)
| | - Madeline A Shea
- Department of Biochemistry, Carver College of Medicine, University of Iowa (H.M.I., M.A.S.)
| | - Pascale Guicheney
- Sorbonne Université, Inserm, Research Unit on Cardiovascular and Metabolic Diseases, UMRS-1166, Paris, France (K.K., V.F., I.D., A.D., A.C., P.G.)
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89
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Shivkumar K, Zipes DP. Cardiac Sympathectomy and its Enduring Value for the Management of Long QT Syndrome. JACC Clin Electrophysiol 2022; 8:295-296. [PMID: 35331423 DOI: 10.1016/j.jacep.2021.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 11/04/2021] [Indexed: 10/18/2022]
Affiliation(s)
- Kalyanam Shivkumar
- UCLA Cardiac Arrhythmia Center, UCLA Health System, David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
| | - Douglas P Zipes
- Krannert Institute of Cardiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
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90
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Charisopoulou D, Koulaouzidis G, Rydberg A, Henein MY. Reversed Apico-Basal Myocardial Relaxation Sequence During Exercise in Long QT Syndrome Mutations Carriers With History of Previous Cardiac Events. Front Physiol 2022; 12:780448. [PMID: 35197859 PMCID: PMC8859439 DOI: 10.3389/fphys.2021.780448] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 12/30/2021] [Indexed: 11/22/2022] Open
Abstract
Background Recent echocardiography studies in inherited long QT syndrome (LQTS) have shown left ventricular (LV) myocardial relaxation disturbances to follow markedly prolonged and dispersed mechanical contraction. Aim We used speckle-tracking echocardiography to assess disturbances in LV myocardial relaxation sequence during exercise and their relationship to symptoms. Methods Forty seven LQTS patients (45 ± 15 years, 25 female and 20 symptomatic, LVEF: 65 ± 6%) and 35 controls underwent exercise echocardiogram using Bruce protocol. ECG and echo parameters were recorded at rest, peak exercise (p.e.) and recovery. Results Between patients and controls there were no differences in age, gender, HR or LVEF. At p.e, patients had longer time to LV longitudinal ESR (tESR) at all three LV segments; basal (p < 0.0001), mid- cavity (p = 0.03) and apical (p = 0.03) whereas at rest such difference was noted only at base (p = 0.0007). Patients showed reversed apico-basal relaxation sequence (ΔtESRbase–apex) with early relaxation onset occurring later at base than at apex, both at rest (49 ± 43 vs. –29 ± 19 ms, p < 0.0001) and at p.e. (46 ± 38 vs. –40 ± 22 ms, p < 0.0001), particularly in symptomatic patients (69 ± 44 vs. 32 ± 26, p < 0.0007). ΔtESRbase–apex correlated with longer QTc interval, lower ESR and attenuated LV stroke volume. Conclusion LQTS patients show reversed longitudinal relaxation sequence, which worsens with exercise, particularly in those with previous cardiac events.
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Affiliation(s)
- Dafni Charisopoulou
- Institute of Public Health and Clinical Medicine, Umea University, Umeå, Sweden.,Division of Pediatric Cardiology, Department of Pediatrics, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands.,Academic Centre for Congenital Heart Disease, Nijmegen, Netherlands
| | - George Koulaouzidis
- Department of Biochemical Sciences, Pomeranian Medical University, Szczecin, Poland
| | - Annika Rydberg
- Department of Clinical Sciences, Paediatrics, Umea University, Umeå, Sweden
| | - Michael Y Henein
- Institute of Public Health and Clinical Medicine, Umea University, Umeå, Sweden
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91
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Gray B, Baruteau AE, Antolin AA, Pittman A, Sarganas G, Molokhia M, Blom MT, Bastiaenen R, Bardai A, Priori SG, Napolitano C, Weeke PE, Shakir SA, Haverkamp W, Mestres J, Winkel BG, Witney AA, Chis-Ster I, Sangaralingam A, Camm AJ, Tfelt-Hansen J, Roden DM, Tan HL, Garbe E, Sturkenboom M, Behr ER. Rare Variation in Drug Metabolism and Long QT Genes and the Genetic Susceptibility to Acquired Long QT Syndrome. Circ Genom Precis Med 2022; 15:e003391. [PMID: 35113648 DOI: 10.1161/circgen.121.003391] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Acquired long QT syndrome (aLQTS) is a serious unpredictable adverse drug reaction. Pharmacogenomic markers may predict risk. METHODS Among 153 aLQTS patients (mean age 58 years [range, 14-88], 98.7% White, 85.6% symptomatic), computational methods identified proteins interacting most significantly with 216 QT-prolonging drugs. All cases underwent sequencing of 31 candidate genes arising from this analysis or associating with congenital LQTS. Variants were filtered using a minor allele frequency <1% and classified for susceptibility for aLQTS. Gene-burden analyses were then performed comparing the primary cohort to control exomes (n=452) and an independent replication aLQTS exome sequencing cohort. RESULTS In 25.5% of cases, at least one rare variant was identified: 22.2% of cases carried a rare variant in a gene associated with congenital LQTS, and in 4% of cases that variant was known to be pathogenic or likely pathogenic for congenital LQTS; 7.8% cases carried a cytochrome-P450 (CYP) gene variant. Of 12 identified CYP variants, 11 (92%) were in an enzyme known to metabolize at least one culprit drug to which the subject had been exposed. Drug-drug interactions that affected culprit drug metabolism were found in 19% of cases. More than one congenital LQTS variant, CYP gene variant, or drug interaction was present in 7.8% of cases. Gene-burden analyses of the primary cohort compared to control exomes (n=452), and an independent replication aLQTS exome sequencing cohort (n=67) and drug-tolerant controls (n=148) demonstrated an increased burden of rare (minor allele frequency<0.01) variants in CYP genes but not LQTS genes. CONCLUSIONS Rare susceptibility variants in CYP genes are emerging as potentially important pharmacogenomic risk markers for aLQTS and could form part of personalized medicine approaches in the future.
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Affiliation(s)
- Belinda Gray
- Cardiology Clinical Academic Group, Molecular & Clinical Sciences Research Institute, St George's, University of London & St George's University Hospitals NHS Foundation Trust, London, United Kingdom (B.G., A.-E.B., R.B., A.S., A.J.C., E.R.B.)
| | - Alban-Elouen Baruteau
- Cardiology Clinical Academic Group, Molecular & Clinical Sciences Research Institute, St George's, University of London & St George's University Hospitals NHS Foundation Trust, London, United Kingdom (B.G., A.-E.B., R.B., A.S., A.J.C., E.R.B.)
- L'institut du thorax, INSERM, CNRS, UNIV Nantes, CHU Nantes, Nantes, France (A.-E.B.)
| | - Albert A Antolin
- Systems Pharmacology, Research Program on Biomedical Informatics (GRIB), IMIM Hospital del Mar Medical Research Institute & University Pompeu Fabra, Parc de Recerca Biomedica, Barcelona, Catalonia, Spain (A.A.A., M.J.M.)
| | - Alan Pittman
- Genetics Research Centre (A.P.), St George's University of London, United Kingdom
| | - Giselle Sarganas
- Clinical Pharmacology & Toxicology, Charite Universitaetsmedizin, Berlin, Germany (G.S.)
| | - Mariam Molokhia
- Department of Population Health Sciences, King's College London, United Kingdom (M.M.)
| | - Marieke T Blom
- Heart Centre AMC, Department of Experimental & Clinical Cardiology, Academic Medical Center, Amsterdam, the Netherlands (M.T.B., A.B., H.L.T.)
| | - Rachel Bastiaenen
- Cardiology Clinical Academic Group, Molecular & Clinical Sciences Research Institute, St George's, University of London & St George's University Hospitals NHS Foundation Trust, London, United Kingdom (B.G., A.-E.B., R.B., A.S., A.J.C., E.R.B.)
| | - Abdenasser Bardai
- Heart Centre AMC, Department of Experimental & Clinical Cardiology, Academic Medical Center, Amsterdam, the Netherlands (M.T.B., A.B., H.L.T.)
| | - Silvia G Priori
- Molecular Cardiology, IRCCS ICS Maugeri, Pavia, Italy (S.G.P., C.N.)
- Department of Molecular Medicine, University of Pavia, Italy (S.G.P., C.N.)
| | - Carlo Napolitano
- Molecular Cardiology, IRCCS ICS Maugeri, Pavia, Italy (S.G.P., C.N.)
- Department of Molecular Medicine, University of Pavia, Italy (S.G.P., C.N.)
| | - Peter E Weeke
- L'institut du thorax, INSERM, CNRS, UNIV Nantes, CHU Nantes, Nantes, France (A.-E.B.)
- Departments of Medicine, Pharmacology & Biomedical Informatics Vanderbilt University Medical Centre (P.E.W., D.M.R.)
| | - Saad A Shakir
- Drug Safety Research Unit, Bursledon Hall, Blundell Lane, Southampton, United Kingdom (S.A.S.)
- Associate Department of the School of Pharmacy & Biomedical Sciences, University of Portsmouth, United Kingdom (S.A.S.)
| | - Wilhelm Haverkamp
- Charité-Campus Virchow-Klinikum (CVK), Department of Cardiology, Berlin, Germany (W.H.)
| | - Jordi Mestres
- Systems Pharmacology, Research Program on Biomedical Informatics (GRIB), IMIM Hospital del Mar Medical Research Institute & University Pompeu Fabra, Parc de Recerca Biomedica, Barcelona, Catalonia, Spain (A.A.A., M.J.M.)
| | - Bo Gregers Winkel
- Department of Forensic Medicine, Faculty of Medical Sciences, University of Copenhagen, Denmark (B.W., J.T.-H.)
- Department of Cardiology, The Heart Centre, Copenhagen University Hospital, Rigshospitalet, Denmark (P.E.W., B.W., J.T.-H.)
| | - Adam A Witney
- Institute of Infection & Immunity (A.A.W., I.C.-S.), St George's University of London, United Kingdom
| | - Irina Chis-Ster
- Institute of Infection & Immunity (A.A.W., I.C.-S.), St George's University of London, United Kingdom
| | - Ajanthah Sangaralingam
- Cardiology Clinical Academic Group, Molecular & Clinical Sciences Research Institute, St George's, University of London & St George's University Hospitals NHS Foundation Trust, London, United Kingdom (B.G., A.-E.B., R.B., A.S., A.J.C., E.R.B.)
| | - A John Camm
- Cardiology Clinical Academic Group, Molecular & Clinical Sciences Research Institute, St George's, University of London & St George's University Hospitals NHS Foundation Trust, London, United Kingdom (B.G., A.-E.B., R.B., A.S., A.J.C., E.R.B.)
| | - Jacob Tfelt-Hansen
- Department of Cardiology, The Heart Centre, Copenhagen University Hospital, Rigshospitalet, Denmark (P.E.W., B.W., J.T.-H.)
- Department of Forensic Medicine, Faculty of Medical Sciences, University of Copenhagen, Denmark (B.W., J.T.-H.)
| | - Dan M Roden
- Departments of Medicine, Pharmacology & Biomedical Informatics Vanderbilt University Medical Centre (P.E.W., D.M.R.)
| | - Hanno L Tan
- Heart Centre AMC, Department of Experimental & Clinical Cardiology, Academic Medical Center, Amsterdam, the Netherlands (M.T.B., A.B., H.L.T.)
| | - Edeltraut Garbe
- Leibniz Institute for Prevention Research & Epidemiology - BIPS, Bremen, Germany (E.G.)
| | - Miriam Sturkenboom
- Julius Global Health, University Medical Center Utrecht, the Netherlands (M.S.)
| | - Elijah R Behr
- Cardiology Clinical Academic Group, Molecular & Clinical Sciences Research Institute, St George's, University of London & St George's University Hospitals NHS Foundation Trust, London, United Kingdom (B.G., A.-E.B., R.B., A.S., A.J.C., E.R.B.)
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Wada Y, Yang T, Shaffer CM, Daniel LL, Glazer AM, Davogustto GE, Lowery BD, Farber-Eger E, Wells QS, Roden DM. Common Ancestry-Specific Ion Channel Variants Predispose to Drug-Induced Arrhythmias. Circulation 2022; 145:299-308. [PMID: 34994586 PMCID: PMC8852297 DOI: 10.1161/circulationaha.121.054883] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND Multiple reports associate the cardiac sodium channel gene (SCN5A) variants S1103Y and R1193Q with type 3 congenital long QT syndrome and drug-induced long QT syndrome. These variants are too common in ancestral populations to be highly arrhythmogenic at baseline, however: S1103Y allele frequency is 8.1% in African Americans and R1193Q 6.1% in East Asians. R1193Q is known to increase late sodium current (INa-L) in cardiomyocytes derived from induced pluripotent stem cells but the role of these variants in modulating repolarization remains poorly understood. METHODS We determined the effect of S1103Y on QT intervals among African-American participants in a large electronic health record. Using cardiomyocytes derived from induced pluripotent stem cells carrying naturally occurring or genome-edited variants, we studied action potential durations (APDs) at baseline and after challenge with the repolarizing potassium current (IKr) blocker dofetilide and INa-L and IKr at baseline. RESULTS In 1479 African-American participants with no confounding medications or diagnoses of heart disease, QT intervals in S1103Y carriers was no different from that in noncarriers. Baseline APD was no different in cells expressing the Y allele (SY, YY cells) compared with isogenic cells with the reference allele (SS cells). However, INa-L was increased in SY and YY cells and the INa-L blocker GS967 shortened APD in SY/YY but not SS cells (P<0.001). IKr was increased almost 2-fold in SY/YY cells compared with SS cells (tail current: 0.66±0.1 versus 1.2±0.1 pA/pF; P<0.001). Dofetilide challenge prolonged APD at much lower concentrations in SY (4.1 nmol/L [interquartile range, 1.5-9.3]; n=11) and YY (4.2 nmol/L [1.7-5.0]; n=5) than in SS cells (249 nmol/L [22.3-2905]; n=14; P<0.001 and P<0.01, respectively) and elicited afterdepolarizations in 8/16 SY/YY cells but only in 1/14 SS cells. R1193Q cells similarly displayed no difference in baseline APD but increased IKr and increased dofetilide sensitivity. CONCLUSIONS These common ancestry-specific variants do not affect baseline repolarization, despite generating increased INa-L. We propose that increased IKr serves to maintain normal repolarization but increases the risk of manifest QT prolongation with IKr block in variant carriers. Our findings emphasize the need for inclusion of diverse populations in the study of adverse drug reactions.
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Affiliation(s)
- Yuko Wada
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Tao Yang
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | | | - Laura L. Daniel
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Andrew M. Glazer
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | | | - Brandon D. Lowery
- Vanderbilt Institute for Clinical and Translational Research, Vanderbilt University Medical Center, Nashville, TN
| | - Eric Farber-Eger
- Vanderbilt Institute for Clinical and Translational Research, Vanderbilt University Medical Center, Nashville, TN
| | - Quinn S. Wells
- Departments of Medicine, Pharmacology, and Biomedical Informatics, Vanderbilt University Medical Center, Nashville, TN
| | - Dan M. Roden
- Departments of Medicine, Pharmacology, and Biomedical Informatics, Vanderbilt University Medical Center, Nashville, TN.,For correspondence: Dan M. Roden, M.D., Vanderbilt University Medical Center, 2215B Garland Ave, 1285 MRBIV, Nashville, TN 37232. Fax 615.343.4522, Tel 615.322.0067,
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Martínez-Barrios E, Cesar S, Cruzalegui J, Hernandez C, Arbelo E, Fiol V, Brugada J, Brugada R, Campuzano O, Sarquella-Brugada G. Clinical Genetics of Inherited Arrhythmogenic Disease in the Pediatric Population. Biomedicines 2022; 10:106. [PMID: 35052786 PMCID: PMC8773373 DOI: 10.3390/biomedicines10010106] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 12/27/2021] [Accepted: 12/31/2021] [Indexed: 12/19/2022] Open
Abstract
Sudden death is a rare event in the pediatric population but with a social shock due to its presentation as the first symptom in previously healthy children. Comprehensive autopsy in pediatric cases identify an inconclusive cause in 40-50% of cases. In such cases, a diagnosis of sudden arrhythmic death syndrome is suggested as the main potential cause of death. Molecular autopsy identifies nearly 30% of cases under 16 years of age carrying a pathogenic/potentially pathogenic alteration in genes associated with any inherited arrhythmogenic disease. In the last few years, despite the increasing rate of post-mortem genetic diagnosis, many families still remain without a conclusive genetic cause of the unexpected death. Current challenges in genetic diagnosis are the establishment of a correct genotype-phenotype association between genes and inherited arrhythmogenic disease, as well as the classification of variants of uncertain significance. In this review, we provide an update on the state of the art in the genetic diagnosis of inherited arrhythmogenic disease in the pediatric population. We focus on emerging publications on gene curation for genotype-phenotype associations, cases of genetic overlap and advances in the classification of variants of uncertain significance. Our goal is to facilitate the translation of genetic diagnosis to the clinical area, helping risk stratification, treatment and the genetic counselling of families.
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Affiliation(s)
- Estefanía Martínez-Barrios
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
| | - Sergi Cesar
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
| | - José Cruzalegui
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
| | - Clara Hernandez
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
| | - Elena Arbelo
- Centro de Investigación Biomédica en Red, Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (E.A.); (R.B.)
- Arrhythmias Unit, Hospital Clinic, University of Barcelona-IDIBAPS, 08036 Barcelona, Spain
| | - Victoria Fiol
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
| | - Josep Brugada
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
- Centro de Investigación Biomédica en Red, Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (E.A.); (R.B.)
- Arrhythmias Unit, Hospital Clinic, University of Barcelona-IDIBAPS, 08036 Barcelona, Spain
| | - Ramon Brugada
- Centro de Investigación Biomédica en Red, Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (E.A.); (R.B.)
- Medical Science Department, School of Medicine, University of Girona, 17004 Girona, Spain
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Girona, Spain
- Cardiology Service, Hospital Josep Trueta, University of Girona, 17007 Girona, Spain
| | - Oscar Campuzano
- Centro de Investigación Biomédica en Red, Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (E.A.); (R.B.)
- Medical Science Department, School of Medicine, University of Girona, 17004 Girona, Spain
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Girona, Spain
| | - Georgia Sarquella-Brugada
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
- Medical Science Department, School of Medicine, University of Girona, 17004 Girona, Spain
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94
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Zheng Z, Cai D, Fu Y, Wang Y, Song Y, Lian J. Chronic Administration of COVID-19 Drugs Fluvoxamine and Lopinavir Shortens Action Potential Duration by Inhibiting the Human Ether-à-go-go-Related Gene and Cav1.2. Front Pharmacol 2022; 13:889713. [PMID: 35873575 PMCID: PMC9301601 DOI: 10.3389/fphar.2022.889713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 06/07/2022] [Indexed: 02/05/2023] Open
Abstract
Background: Old drugs for new indications in the novel coronavirus disease of 2019 (COVID-19) pandemic have raised concerns regarding cardiotoxicity, especially the development of drug-induced QT prolongation. The acute blocking of the cardiac hERG potassium channel is conventionally thought to be the primary mechanism of QT prolongation induced by COVID-19 drugs fluvoxamine (FLV) and lopinavir (LPV). The chronic impact of these medications on the hERG expression has yet to be determined. Methods: To investigate the effect of long-term incubation of FLV and LPV on the hERG channel, we used electrophysiological assays and molecular experiments, such as Western blot, RT-qPCR, and immunofluorescence, in HEK-293 cells stably expressing hERG and human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). Results: Compared to the acute effects, chronic incubation for FLV and LPV generated much lower half-maximal inhibitory concentration (IC50) values, along with a left-shifted activation curve and retarded channel activation. Inconsistent with the reduction in current, we unexpectedly found that the chronic effects of drugs promoted the maturation of hERG proteins, accompanied by the high expression of Hsp70 and low expression of Hsp90. Targeting Hsp70 using siRNA was able to reverse the effects of these drugs on hERG proteins. In addition, FLV and LPV resulted in a significant reduction of APD90 and triggered the early after-depolarizations (EADs), as well as inhibited the protein level of the L-type voltage-operated calcium channel (L-VOCC) in hiPSC-CMs. Conclusion: Chronic incubation with FLV and LPV produced more severe channel-blocking effects and contributed to altered channel gating and shortened action potential duration by inhibiting hERG and Cav1.2.
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Affiliation(s)
- Zequn Zheng
- Department of Cardiovascular, Lihuili Hospital Facilitated to Ningbo University, Ningbo University, Ningbo, China
- Ningbo Institute of Innovation for Combined Medicine and Engineering, Ningbo, China
- Department of Cardiovascular Medicine, First Affiliated Hospital of Shantou University Medical College, Shantou, China
| | - Dihui Cai
- Department of Cardiovascular, Lihuili Hospital Facilitated to Ningbo University, Ningbo University, Ningbo, China
- Ningbo Institute of Innovation for Combined Medicine and Engineering, Ningbo, China
| | - Yin Fu
- Department of Cardiovascular, Lihuili Hospital Facilitated to Ningbo University, Ningbo University, Ningbo, China
- Ningbo Institute of Innovation for Combined Medicine and Engineering, Ningbo, China
| | - Ying Wang
- Department of Cardiovascular, Lihuili Hospital Facilitated to Ningbo University, Ningbo University, Ningbo, China
| | - Yongfei Song
- Department of Cardiovascular, Lihuili Hospital Facilitated to Ningbo University, Ningbo University, Ningbo, China
- Ningbo Institute of Innovation for Combined Medicine and Engineering, Ningbo, China
- *Correspondence: Yongfei Song , ; Jiangfang Lian,
| | - Jiangfang Lian
- Department of Cardiovascular, Lihuili Hospital Facilitated to Ningbo University, Ningbo University, Ningbo, China
- Ningbo Institute of Innovation for Combined Medicine and Engineering, Ningbo, China
- *Correspondence: Yongfei Song , ; Jiangfang Lian,
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95
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Abstract
To our knowledge, this is the first report describing a case of vonoprazan-associated QT prolongation newly occurring after initiation of the drug and improving after its discontinuation in a patient concurrently receiving polypharmacy including a drug metabolized by CYP3A4.
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Affiliation(s)
- Kimitoshi Kubo
- Department of GastroenterologyNational Hospital Organization Hakodate National HospitalHakodateHokkaidoJapan
| | - Toru Sakakibara
- Sakakibara Cardiology and Internal Medicine ClinicHakodateHokkaidoJapan
| | - Kazuya Yonezawa
- Department of CardiologyNational Hospital Organization Hakodate National HospitalHakodateHokkaidoJapan
| | - Mototsugu Kato
- Department of GastroenterologyNational Hospital Organization Hakodate National HospitalHakodateHokkaidoJapan
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96
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Caiffa T, Tessitore A, Leoni L, Reffo E, Chicco D, D'Agata Mottolese B, Rubinato E, Girotto G, Lenarduzzi S, Barbi E, Bobbo M, Di Salvo G. Long QT syndrome and left ventricular non-compaction in a family with KCNH2 mutation: A case report. Front Pediatr 2022; 10:970240. [PMID: 35989994 PMCID: PMC9386155 DOI: 10.3389/fped.2022.970240] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 07/12/2022] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Left ventricular non-compaction (LVNC) is an abnormality of the myocardium, characterized by prominent left ventricular trabeculae and deep inter-trabecular recesses. Long QT syndrome (LQTS) is a cardiac ion channelopathy presenting with a prolonged QT interval on resting electrocardiogram and is associated with increased susceptibility to sudden death. The association between LVNC and LQTS is uncommon. CASE PRESENTATION We report an Italian family with a novel pathogenic KCNH2 variant who presented with clinical features of LVNC and LQTS. The proband came to our attention after two syncopal episodes without prodromal symptoms. His ECG showed QTc prolongation and deep T wave inversion in anterior leads, and the echocardiogram fulfilled LVNC criteria. After that, also his sister was found to have LQTS and LVNC, while his father only presented LQTS. CONCLUSIONS Physicians should be aware of the possible association between LVNC and LQTS. Even if this association is rare, patients with LVNC should be investigated for LQTS to prevent possible severe or even life-threatening arrhythmic episodes.
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Affiliation(s)
- Thomas Caiffa
- Department of Paediatrics, Institute for Maternal and Child Health IRCCS 'Burlo Garofolo', Trieste, Italy
| | - Antimo Tessitore
- Department of Medicine, Surgery and Health Sciences, Department of Paediatrics, University of Trieste, Trieste, Italy
| | - Loira Leoni
- Cardiology Clinic, Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University of Padova Medical School, Padova, Italy
| | - Elena Reffo
- Pediatric Cardiology Unit, Department of Woman and Child's Health, University of Padova Medical School, Padova, Italy
| | - Daniela Chicco
- Department of Paediatrics, Institute for Maternal and Child Health IRCCS 'Burlo Garofolo', Trieste, Italy
| | | | - Elisa Rubinato
- Medical Genetics, Institute for Maternal and Child Health - IRCCS "Burlo Garofolo," Trieste, Italy
| | - Giorgia Girotto
- Medical Genetics, Institute for Maternal and Child Health - IRCCS "Burlo Garofolo," Trieste, Italy.,Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Stefania Lenarduzzi
- Medical Genetics, Institute for Maternal and Child Health - IRCCS "Burlo Garofolo," Trieste, Italy
| | - Egidio Barbi
- Department of Paediatrics, Institute for Maternal and Child Health IRCCS 'Burlo Garofolo', Trieste, Italy.,Department of Medicine, Surgery and Health Sciences, Department of Paediatrics, University of Trieste, Trieste, Italy
| | - Marco Bobbo
- Department of Paediatrics, Institute for Maternal and Child Health IRCCS 'Burlo Garofolo', Trieste, Italy
| | - Giovanni Di Salvo
- Pediatric Cardiology Unit, Department of Woman and Child's Health, University of Padova Medical School, Padova, Italy
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97
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Hamrick SK, Kim CJ, Tester DJ, Giudicessi JR, Ackerman MJ. A Patient-Specific Re-Engineered Cardiomyocyte Model Confirms the Circumstance-Dependent Arrhythmia Risk Associated with the African-Specific Common SCN5A Polymorphism (p.S1103Y): Implications for the Increased Sudden Deaths Observed in Black Individuals During the COVID-19 Pandemic. Heart Rhythm 2021; 19:822-827. [PMID: 34979239 DOI: 10.1016/j.hrthm.2021.12.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 12/14/2021] [Accepted: 12/24/2021] [Indexed: 12/19/2022]
Abstract
BACKGROUND During the early stages of the coronavirus disease 2019 (COVID-19) pandemic, a marked increase in sudden cardiac death (SCD) was observed. The p.S1103Y-SCN5A common variant, present in ∼8% of individuals of African descent, may be a circumstance-dependent, SCD-predisposing, pro-arrhythmic polymorphism in the setting of hypoxia-induced acidosis or QT-prolonging drug use. OBJECTIVE To ascertain the effects of acidosis and hydroxychloroquine (HCQ) on the action potential duration (APD) in a patient-specific induced pluripotent stem cell cardiomyocyte (iPSC-CM) model of p.S1103Y-SCN5A. METHODS iPSC-CMs were generated from a 14-year-old p.S1103Y-SCN5A-positive African American male. The patient's variant-corrected iPSC-CMs (isogenic control, IC) were generated using CRISPR/Cas9 technology. FluoVolt voltage sensing dye was used to assess APD90 values in p.S1103Y-SCN5A-iPSC-CMs compared to IC before and after an acidotic state (pH 6.9) or 24 hours of treatment with 10 μM HCQ. RESULTS Under baseline conditions (pH 7.4), there was no difference in APD90 values of p.S1103Y-SCN5A versus isogenic control iPSC-CMs (p = NS). In the setting of acidosis (pH 6.9), there was a significant increase in fold-change of APD90 in p.S1103Y-SCN5A iPSC-CMS compared to IC iPSC-CMs (p < 0.0001). Similarly, with 24h 10 μM HCQ treatment, the fold-change of APD90 was significantly higher in p.S1103Y-SCN5A iPSC-CMs compared to IC iPSC-CMs (p < 0.0001). CONCLUSIONS Although the African-specific p.S1103Y-SCN5A common variant had no effect on APD90 under baseline conditions, the physiologic stress of either acidosis or HCQ treatment significantly prolonged the APD90 in patient-specific, re-engineered heart cells.
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Affiliation(s)
- Samantha K Hamrick
- Departments of Cardiovascular Medicine (Division of Heart Rhythm Services), Pediatric and Adolescent Medicine (Division of Pediatric Cardiology), and Molecular Pharmacology & Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory), Mayo Clinic, Rochester, MN
| | - Cs John Kim
- Departments of Cardiovascular Medicine (Division of Heart Rhythm Services), Pediatric and Adolescent Medicine (Division of Pediatric Cardiology), and Molecular Pharmacology & Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory), Mayo Clinic, Rochester, MN
| | - David J Tester
- Departments of Cardiovascular Medicine (Division of Heart Rhythm Services), Pediatric and Adolescent Medicine (Division of Pediatric Cardiology), and Molecular Pharmacology & Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory), Mayo Clinic, Rochester, MN
| | - John R Giudicessi
- Departments of Cardiovascular Medicine (Division of Heart Rhythm Services), Pediatric and Adolescent Medicine (Division of Pediatric Cardiology), and Molecular Pharmacology & Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory), Mayo Clinic, Rochester, MN; Departments of Cardiovascular Medicine (Clinician-Investigator Training Program), Mayo Clinic, Rochester, MN
| | - Michael J Ackerman
- Departments of Cardiovascular Medicine (Division of Heart Rhythm Services), Pediatric and Adolescent Medicine (Division of Pediatric Cardiology), and Molecular Pharmacology & Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory), Mayo Clinic, Rochester, MN.
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98
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Noguchi Y, Tachi T, Teramachi H. Comment on: 'Detecting drug-drug interactions that increase the incidence of long QT syndrome using a spontaneous reporting system' by Matsuo et al. J Clin Pharm Ther 2021; 47:709-710. [PMID: 34964163 DOI: 10.1111/jcpt.13592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 12/13/2021] [Indexed: 11/30/2022]
Affiliation(s)
- Yoshihiro Noguchi
- Laboratory of Clinical Pharmacy, Gifu Pharmaceutical University, Gifu, Japan
| | - Tomoya Tachi
- Laboratory of Clinical Pharmacy, Gifu Pharmaceutical University, Gifu, Japan
| | - Hitomi Teramachi
- Laboratory of Clinical Pharmacy, Gifu Pharmaceutical University, Gifu, Japan
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99
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Villarreal-Molina T, García-Ordóñez GP, Reyes-Quintero ÁE, Domínguez-Pérez M, Jacobo-Albavera L, Nava S, Carnevale A, Medeiros-Domingo A, Iturralde P. Clinical Spectrum of SCN5A Channelopathy in Children with Primary Electrical Disease and Structurally Normal Hearts. Genes (Basel) 2021; 13:16. [PMID: 35052356 DOI: 10.3390/genes13010016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/11/2021] [Accepted: 12/18/2021] [Indexed: 12/19/2022] Open
Abstract
Sodium voltage-gated channel α subunit 5 (SCN5A)-mutations may cause an array of arrhythmogenic syndromes most frequently as an autosomal dominant trait, with incomplete penetrance, variable expressivity and male predominance. In the present study, we retrospectively describe a group of Mexican patients with SCN5A-disease causing variants in whom the onset of symptoms occurred in the pediatric age range. The study included 17 patients with clinical diagnosis of primary electrical disease, at least one SCN5A pathogenic or likely pathogenic mutation and age of onset <18 years, and all available first- and second-degree relatives. Fifteen patients (88.2%) were male, and sixteen independent variants were found (twelve missense, three truncating and one complex inframe deletion/insertion). The frequency of compound heterozygosity was remarkably high (3/17, 17.6%), with early childhood onset and severe disease. Overall, 70.6% of pediatric patients presented with overlap syndrome, 11.8% with isolated sick sinus syndrome, 11.8% with isolated Brugada syndrome (BrS) and 5.9% with isolated type 3 long QT syndrome (LQTS). A total of 24/45 SCN5A mutation carriers were affected (overall penetrance 53.3%), and penetrance was higher in males (63.3%, 19 affected/30 mutation carriers) than in females (33.3%, 5 affected/15 carriers). In conclusion, pediatric patients with SCNA-disease causing variants presented mainly as overlap syndrome, with predominant loss-of-function phenotypes of sick sinus syndrome (SSS), progressive cardiac conduction disease (PCCD) and ventricular arrhythmias.
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100
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Akgun-Dogan O, Ağaoğlu NB, K Demirkol Y, Doğanay L, Ergül Y, Karacan M. Mutational spectrum of congenital long QT syndrome in Turkey; identification of 12 novel mutations across KCNQ1, KCNH2, SCN5A, KCNJ2, CACNA1C, and CALM1. J Cardiovasc Electrophysiol 2021; 33:262-273. [PMID: 34860437 DOI: 10.1111/jce.15306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 10/10/2021] [Accepted: 11/08/2021] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Long QT syndrome (LQTS) is of great importance as it is the most common cause of sudden cardiac death in childhood. The diagnosis is made by the prolongation of the QTc interval on the electrocardiography. However, clinical heterogeneity and nondiagnostic QTc intervals may cause a delay in the diagnosis. In such cases, genetic tests such as next-generation sequencing (NGS) panel analysis enable a definitive diagnosis. We present the first study that aimed to expand the LQTS's mutational spectrum by NGS panel analysis from Turkey. METHODS Fifty-seven unrelated patients with clinically diagnosed LQTS were investigated using an NGS panel that includes six LQTS-related genes. Clinical aspects, outcome, and molecular analysis results were reviewed. RESULTS Pathogenic (53%)/likely pathogenic (23%)/variant of unknown significance (4%) variants were detected in any of the genes examined in 79% of the patients. Among all detected variants, KCNQ1(71%) was the most common gene, followed by SCN5A (11%), KCNH2 (10%), CALM1 (5%), and CACNA1C (3%). Twelve novel variants were detected. Among the variants in KCNQ1, the c.1097G>A variant was present in 42% of patients. This variant also composed 31% of the variants detected in all of the genes. CONCLUSION Our study expands the spectrum of the variations associated with LQTS with twelve novel variants in five genes. And also it draws attention to the frequency of the KCNQ1 c.1097G>A variant and forms the basis for new studies to determine the possible founder effect in the Turkish population. Furthermore, identifying new variants and clinical findings has importance in elaborating the roles of related genes in pathophysiology and determining the variable expression and incomplete penetration rates in this syndrome.
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Affiliation(s)
- Ozlem Akgun-Dogan
- Division of Pediatric Genetics, Umraniye Training and Research Hospital, Istanbul, Turkey
| | - Nihat B Ağaoğlu
- Department of Medical Genetics, Umraniye Training and Research Hospital, Istanbul, Turkey
| | - Yasemin K Demirkol
- Division of Pediatric Genetics, Umraniye Training and Research Hospital, Istanbul, Turkey
| | - Levent Doğanay
- Department of Internal Medicine, Genomic Laboratory (GLAB), Umraniye Training and Research Hospital, Istanbul, Turkey
| | - Yakup Ergül
- Department of Pediatric Cardiology, Mehmet Akif Ersoy Thoracic and Cardiovascular Research and Education Hospital, Istanbul, Turkey
| | - Mehmet Karacan
- Department of Pediatric Cardiology, Umraniye Training and Research Hospital, Istanbul, Turkey
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