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Scacchi S, Pavarino LF, Mazzanti A, Trancuccio A, Priori SG, Colli Franzone P. Transmural APD heterogeneity determines ventricular arrhythmogenesis in LQT8 syndrome: Insights from Bidomain computational modeling. PLoS One 2024; 19:e0305248. [PMID: 38968219 PMCID: PMC11226139 DOI: 10.1371/journal.pone.0305248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Accepted: 05/27/2024] [Indexed: 07/07/2024] Open
Abstract
Long QT Syndrome type 8 (LQT8) is a cardiac arrhythmic disorder associated with Timothy Syndrome, stemming from mutations in the CACNA1C gene, particularly the G406R mutation. While prior studies hint at CACNA1C mutations' role in ventricular arrhythmia genesis, the mechanisms, especially in G406R presence, are not fully understood. This computational study explores how the G406R mutation, causing increased transmural dispersion of repolarization, induces and sustains reentrant ventricular arrhythmias. Using three-dimensional numerical simulations on an idealized left-ventricular model, integrating the Bidomain equations with the ten Tusscher-Panfilov ionic model, we observe that G406R mutation with 11% and 50% heterozygosis significantly increases transmural dispersion of repolarization. During S1-S4 stimulation protocols, these gradients facilitate conduction blocks, triggering reentrant ventricular tachycardia. Sustained reentry pathways occur only with G406R mutation at 50% heterozygosis, while neglecting transmural heterogeneities of action potential duration prevents stable reentry, regardless of G406R mutation presence.
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Affiliation(s)
- Simone Scacchi
- Dipartimento di Matematica, Università degli Studi di Milano, Milano, Italy
| | - Luca F. Pavarino
- Dipartimento di Matematica, Università degli Studi di Pavia, Pavia, Italy
| | - Andrea Mazzanti
- Molecular Cardiology, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Molecular Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Pavia, Italy
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Alessandro Trancuccio
- Molecular Cardiology, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Molecular Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Pavia, Italy
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Silvia G. Priori
- Molecular Cardiology, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Molecular Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Pavia, Italy
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
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de Alencar JN, de Andrade Matos VF, Scheffer MK, Felicioni SP, De Marchi MFN, Martínez-Sellés M. ST segment and T wave abnormalities: A narrative review. J Electrocardiol 2024; 85:7-15. [PMID: 38810594 DOI: 10.1016/j.jelectrocard.2024.05.085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2024] [Revised: 05/12/2024] [Accepted: 05/14/2024] [Indexed: 05/31/2024]
Abstract
INTRODUCTION The electrocardiogram (ECG) is a valuable tool for interpreting ventricular repolarization. This article aims to broaden the diagnostic scope beyond the conventional ischemia-centric approach, integrating an understanding of pathophisiological influences on ST-T wave changes. METHODS A review was conducted on the physiological underpinnings of ventricular repolarization and the pathophisiological processes that can change ECG patterns. The research encompassed primary repolarization abnormalities due to uniform variations in ventricular action potential, secondary changes from electrical or mechanical alterations, and non-ischemic conditions influencing ST-T segments. RESULTS Primary T waves are characterized by symmetrical waves with broad bases and variable QT intervals, indicative of direct myocardial action potential modifications due to ischemia, electrolyte imbalances, and channelopathies. Secondary T waves are asymmetric and often unassociated with significant QT interval changes, suggesting depolarization alterations or changes in cardiac geometry and contractility. CONCLUSION We advocate for a unified ECG analysis, recognizing primary and secondary ST-T changes, and their clinical implications. Our proposed analytical framework enhances the clinician's ability to discern a wide array of cardiac conditions, extending diagnostic accuracy beyond myocardial ischemia.
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Affiliation(s)
| | | | | | | | | | - Manuel Martínez-Sellés
- Cardiology Department, Hospital General Universitario Gregorio Marañón, Instituto de Investigación Sanitaria Gregorio Marañón, CIBERCV, Madrid, Spain; Universidad Europea, Universidad Complutense, Madrid, Spain
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Dahlberg P, Axelsson KJ, Rydberg A, Lundahl G, Gransberg L, Bergfeldt L. Spatiotemporal repolarization dispersion before and after exercise in patients with long QT syndrome type 1 versus controls: probing into the arrhythmia substrate. Am J Physiol Heart Circ Physiol 2023; 325:H1279-H1289. [PMID: 37773058 DOI: 10.1152/ajpheart.00335.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 09/21/2023] [Accepted: 09/22/2023] [Indexed: 09/30/2023]
Abstract
Congenital long QT syndrome (LQTS) carries an increased risk for syncope and sudden death. QT prolongation promotes ventricular extrasystoles, which, in the presence of an arrhythmia substrate, might trigger ventricular tachycardia degenerating into fibrillation. Increased electrical heterogeneity (dispersion) is the suggested arrhythmia substrate in LQTS. In the most common subtype LQT1, physical exercise predisposes for arrhythmia and spatiotemporal dispersion was therefore studied in this context. Thirty-seven patients (57% on β-blockers) and 37 healthy controls (mean age, 31 vs. 35; range, 6-68 vs. 6-72 yr) performed an exercise test. Frank vectorcardiography was used to assess spatiotemporal dispersion as Tampl, Tarea, the ventricular gradient (VG), and the Tpeak-end interval from 10-s signal averages before and 7 ± 2 min after exercise; during exercise too much signal disturbance excluded analysis. Baseline and maximum heart rates as well as estimated exercise intensity were similar, but heart rate recovery was slower in patients. At baseline, QT and heart rate-corrected QT (QTcB) were significantly longer in patients (as expected), whereas dispersion parameters were numerically larger in controls. After exercise, QTpeakcB and Tpeak-endcB increased significantly more in patients (18 ± 23 vs. 7 ± 10 ms and 12 ± 17 vs. 2 ± 6 ms; P < 0.001 and P < 0.01). There was, however, no difference in the change in Tampl, Tarea, and VG between groups. In conclusion, although temporal dispersion of repolarization increased significantly more after exercise in patients with LQT1, there were no signs of exercise-induced increase in global dispersion of action potential duration and morphology. The arrhythmia substrate/mechanism in LQT1 warrants further study.NEW & NOTEWORTHY Physical activity increases the risk for life-threatening arrhythmias in LQTS type 1 (LQT1). The arrhythmia substrate is presumably altered electrical heterogeneity (a.k.a. dispersion). Spatiotemporal dispersion parameters were therefore compared before and after exercise in patients versus healthy controls using Frank vectorcardiography, a novelty. Physical exercise prolonged the time between the earliest and latest complete repolarization in patients versus controls, but did not increase parameters reflecting global dispersion of action potential duration and morphology, another novelty.
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Affiliation(s)
- Pia Dahlberg
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Region Vaestra Goetaland, Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Karl-Jonas Axelsson
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Region Vaestra Goetaland, Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Annika Rydberg
- Division of Pediatrics, Department of Clinical Sciences, Umeå University, Umeå, Sweden
| | - Gunilla Lundahl
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Lennart Gransberg
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Lennart Bergfeldt
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Region Vaestra Goetaland, Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden
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Barro-Soria R. Sensing its own permeant ion: KCNQ1 channel inhibition by external K. J Gen Physiol 2023; 155:e202313337. [PMID: 36961346 PMCID: PMC10072219 DOI: 10.1085/jgp.202313337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023] Open
Abstract
External potassium inhibits KCNQ1 channel through a mechanism involving increased occupancy of the filter S0 site by K+o.
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Affiliation(s)
- Rene Barro-Soria
- Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL, USA
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Ma J, Niklewski PJ, Wang HS. Acute exposure to low-dose bisphenol A delays cardiac repolarization in female canine heart - Implication for proarrhythmic toxicity in large animals. Food Chem Toxicol 2023; 172:113589. [PMID: 36584932 PMCID: PMC9852101 DOI: 10.1016/j.fct.2022.113589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 12/12/2022] [Accepted: 12/24/2022] [Indexed: 12/29/2022]
Abstract
Bisphenol A (BPA) is a common environmental chemical with a range of potential adverse health effects. The impact of environmentally-relevant low dose of BPA on the electrical properties of the hearts of large animals (e.g., dog, human) is poorly defined. Perturbation of cardiac electrical properties is a key arrhythmogenic mechanism. In particular, delay of ventricular repolarization and prolongation of the QT interval of the electrocardiogram is a marker for the risk of malignant arrhythmias. We examined the acute effect of 10-9 M BPA on the electrical properties of female canine ventricular myocytes and tissues. BPA rapidly delayed action potential repolarization and prolonged action potential duration (APD). The dose response curve of BPA on APD was nonmonotonic. BPA rapidly inhibited the IKr K+ current and ICaL Ca2+ current. Computational modeling indicated that the effect of BPA on APD can be accounted for by its suppression of IKr. At the tissue level, BPA acutely prolonged the QT interval in 4 left ventricular wedges. ERβ signaling contributed to the acute effects of BPA on ventricular repolarization. Our results demonstrate that BPA has QT prolongation liability in female canine hearts. These findings have implication for the potential proarrhythmic cardiac toxicity of BPA in large animals.
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Affiliation(s)
- Jianyong Ma
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Paul J Niklewski
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Hong-Sheng Wang
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA.
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Rinné S, Oertli A, Nagel C, Tomsits P, Jenewein T, Kääb S, Kauferstein S, Loewe A, Beckmann BM, Decher N. Functional Characterization of a Spectrum of Novel Romano-Ward Syndrome KCNQ1 Variants. Int J Mol Sci 2023; 24:ijms24021350. [PMID: 36674868 PMCID: PMC9865342 DOI: 10.3390/ijms24021350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 12/20/2022] [Accepted: 12/23/2022] [Indexed: 01/13/2023] Open
Abstract
The KCNQ1 gene encodes the α-subunit of the cardiac voltage-gated potassium (Kv) channel KCNQ1, also denoted as Kv7.1 or KvLQT1. The channel assembles with the ß-subunit KCNE1, also known as minK, to generate the slowly activating cardiac delayed rectifier current IKs, a key regulator of the heart rate dependent adaptation of the cardiac action potential duration (APD). Loss-of-function variants in KCNQ1 cause the congenital Long QT1 (LQT1) syndrome, characterized by delayed cardiac repolarization and a QT interval prolongation in the surface electrocardiogram (ECG). Autosomal dominant loss-of-function variants in KCNQ1 result in the LQT syndrome called Romano-Ward syndrome (RWS), while autosomal recessive variants affecting function, lead to Jervell and Lange-Nielsen syndrome (JLNS), associated with deafness. The aim of this study was the characterization of novel KCNQ1 variants identified in patients with RWS to widen the spectrum of known LQT1 variants, and improve the interpretation of the clinical relevance of variants in the KCNQ1 gene. We functionally characterized nine human KCNQ1 variants using the voltage-clamp technique in Xenopus laevis oocytes, from which we report seven novel variants. The functional data was taken as input to model surface ECGs, to subsequently compare the functional changes with the clinically observed QTc times, allowing a further interpretation of the severity of the different LQTS variants. We found that the electrophysiological properties of the variants correlate with the severity of the clinically diagnosed phenotype in most cases, however, not in all. Electrophysiological studies combined with in silico modelling approaches are valuable components for the interpretation of the pathogenicity of KCNQ1 variants, but assessing the clinical severity demands the consideration of other factors that are included, for example in the Schwartz score.
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Affiliation(s)
- Susanne Rinné
- Institute of Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, 35037 Marburg, Germany
| | - Annemarie Oertli
- Institute of Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, 35037 Marburg, Germany
| | - Claudia Nagel
- Institute of Biomedical Engineering, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
| | - Philipp Tomsits
- Department of Medicine I, University Hospital, LMU Munich, 80802 Munich, Germany
- Deutsches Zentrum für Herz-Kreislauferkrankungen (DZHK), Partner Site Munich, 80636 Munich, Germany
- Member of the European Reference Network for Rare, Low Prevalance and Complex Diseases of the Heart (ERN GUARD-Heart), 81377 Munich, Germany
- Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, University Hospital, LMU Munich, Marchioninistrasse 27, 81377 Munich, Germany
| | - Tina Jenewein
- Institute of Legal Medicine, Goethe University, University Hospital Frankfurt, 60590 Frankfurt, Germany
- Institute for Transfusion Medicine and Immunohematology, German Red Cross Blood Service Baden-Württemberg-Hessen, Goethe University Frankfurt, 60528 Frankfurt, Germany
| | - Stefan Kääb
- Department of Medicine I, University Hospital, LMU Munich, 80802 Munich, Germany
- Deutsches Zentrum für Herz-Kreislauferkrankungen (DZHK), Partner Site Munich, 80636 Munich, Germany
- Member of the European Reference Network for Rare, Low Prevalance and Complex Diseases of the Heart (ERN GUARD-Heart), 81377 Munich, Germany
| | - Silke Kauferstein
- Institute of Legal Medicine, Goethe University, University Hospital Frankfurt, 60590 Frankfurt, Germany
- Deutsches Zentrum für Herz-Kreislauferkrankungen (DZHK), Partner Site Frankfurt, 60596 Frankfurt, Germany
| | - Axel Loewe
- Institute of Biomedical Engineering, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
| | - Britt Maria Beckmann
- Department of Medicine I, University Hospital, LMU Munich, 80802 Munich, Germany
- Institute of Legal Medicine, Goethe University, University Hospital Frankfurt, 60590 Frankfurt, Germany
| | - Niels Decher
- Institute of Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, 35037 Marburg, Germany
- Correspondence: ; Tel.: +49-(0)6421-28-62148
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Kanaporis G, Blatter LA. Activation of small conductance Ca 2+ -activated K + channels suppresses Ca 2+ transient and action potential alternans in ventricular myocytes. J Physiol 2023; 601:51-67. [PMID: 36426548 PMCID: PMC9878619 DOI: 10.1113/jp283870] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 11/22/2022] [Indexed: 11/27/2022] Open
Abstract
At the cellular level, cardiac alternans is observed as beat-to-beat alternations in contraction strength, action potential (AP) morphology and Ca2+ transient (CaT) amplitude, and is a risk factor for cardiac arrhythmia. The (patho)physiological roles of small conductance Ca2+ -activated K+ (SK) channels in ventricles are poorly understood. We tested the hypothesis that in single rabbit ventricular myocytes pharmacological modulation of SK channels plays a causative role for the development of pacing-induced CaT and AP duration (APD) alternans. SK channel blockers (apamin, UCL1684) had only a minor effect on AP repolarization. However, SK channel activation by NS309 resulted in significant APD shortening, demonstrating that functional SK channels are well expressed in ventricular myocytes. The effects of NS309 were prevented or reversed by apamin and UCL1684, indicating that NS309 acted on SK channels. SK channel activation abolished or reduced the degree of pacing-induced CaT and APD alternans. Inhibition of KV 7.1 (with HMR1556) and KV 11.1 (with E4031) channels was used to mimic conditions of long QT syndromes type-1 and type-2, respectively. Both HMR1556 and E4031 enhanced CaT alternans that was prevented by SK channel activation. In AP voltage-clamped cells the SK channel activator had no effect on CaT alternans, confirming that suppression of CaT alternans was caused by APD shortening. APD shortening contributed to protection from alternans by lowering sarcoplasmic reticulum Ca2+ content and curtailing Ca2+ release. The data suggest that SK activation could be a potential intervention to avert development of alternans with important ramifications for arrhythmia prevention and therapy for patients with long QT syndrome. KEY POINTS: At the cellular level, cardiac alternans is observed as beat-to-beat alternations in contraction strength, action potential (AP) morphology and intracellular Ca2+ release amplitude, and is a risk factor for cardiac arrhythmia. The (patho)physiological roles of small conductance Ca2+ -activated K+ (SK) channels in ventricles are poorly understood. We investigated whether pharmacological modulation of SK channels affects the development of cardiac alternans in normal ventricular cells and in cells with drug-induced long QT syndrome (LQTS). While SK channel blockers have only a minor effect on AP morphology, their activation leads to AP shortening and abolishes or reduces the degree of pacing-induced Ca2+ and AP alternans. AP shortening contributed to protection against alternans by lowering sarcoplasmic reticulum Ca2+ content and curtailing Ca2+ release. The data suggest SK activation as a potential intervention to avert the development of alternans with important ramifications for arrhythmia prevention for patients with LQTS.
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Affiliation(s)
- Giedrius Kanaporis
- Department of Physiology & Biophysics, Rush University Medical Center, Chicago, Illinois, USA
| | - Lothar A Blatter
- Department of Physiology & Biophysics, Rush University Medical Center, Chicago, Illinois, USA
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Cardiac Sympathetic Denervation for the Management of Ventricular Arrhythmias. J Interv Card Electrophysiol 2022; 65:813-826. [PMID: 35397706 DOI: 10.1007/s10840-022-01211-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 03/29/2022] [Indexed: 01/01/2023]
Abstract
BACKGROUND The autonomic nervous system contributes to the pathogenesis of ventricular arrhythmias (VA). Though anti-arrhythmic drug therapy and catheter ablation are the mainstay of management of VAs, success may be limited in patients with more refractory arrhythmias. Sympathetic modulation is increasingly recognized as a valuable adjunct tool for managing VAs in patients with structural heart disease and inherited arrhythmias. RESULTS In this review, we explore the role of the sympathetic nervous system and rationale for cardiac sympathetic denervation (CSD) in VAs and provide a disease-focused review of the utility of CSD for patients both with and without structural heart disease. CONCLUSIONS We conclude that CSD is a reasonable therapeutic option for patients with VA, both with and without structural heart disease. Though not curative, many studies have demonstrated a significant reduction in the burden of VAs for the majority of patients undergoing the procedure. However, in patients with unilateral CSD and subsequent VA recurrence, complete bilateral CSD may provide long-lasting reprieve from VA.
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9
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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] [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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10
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Cócera-Ortega L, Wilders R, Kamps SC, Fabrizi B, Huber I, van der Made I, van den Bout A, de Vries DK, Gepstein L, Verkerk AO, Pinto YM, Tijsen AJ. shRNAs Targeting a Common KCNQ1 Variant Could Alleviate Long-QT1 Disease Severity by Inhibiting a Mutant Allele. Int J Mol Sci 2022; 23:ijms23074053. [PMID: 35409410 PMCID: PMC9000197 DOI: 10.3390/ijms23074053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/31/2022] [Accepted: 04/04/2022] [Indexed: 12/02/2022] Open
Abstract
Long-QT syndrome type 1 (LQT1) is caused by mutations in KCNQ1. Patients heterozygous for such a mutation co-assemble both mutant and wild-type KCNQ1-encoded subunits into tetrameric Kv7.1 potassium channels. Here, we investigated whether allele-specific inhibition of mutant KCNQ1 by targeting a common variant can shift the balance towards increased incorporation of the wild-type allele to alleviate the disease in human-induced pluripotent stem-cell-derived cardiomyocytes (hiPSC-CMs). We identified the single nucleotide polymorphisms (SNP) rs1057128 (G/A) in KCNQ1, with a heterozygosity of 27% in the European population. Next, we determined allele-specificity of short-hairpin RNAs (shRNAs) targeting either allele of this SNP in hiPSC-CMs that carry an LQT1 mutation. Our shRNAs downregulated 60% of the A allele and 40% of the G allele without affecting the non-targeted allele. Suppression of the mutant KCNQ1 allele by 60% decreased the occurrence of arrhythmic events in hiPSC-CMs measured by a voltage-sensitive reporter, while suppression of the wild-type allele increased the occurrence of arrhythmic events. Furthermore, computer simulations based on another LQT1 mutation revealed that 60% suppression of the mutant KCNQ1 allele shortens the prolonged action potential in an adult cardiomyocyte model. We conclude that allele-specific inhibition of a mutant KCNQ1 allele by targeting a common variant may alleviate the disease. This novel approach avoids the need to design shRNAs to target every single mutation and opens up the exciting possibility of treating multiple LQT1-causing mutations with only two shRNAs.
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Affiliation(s)
- Lucía Cócera-Ortega
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Ronald Wilders
- Department of Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands;
| | - Selina C. Kamps
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Benedetta Fabrizi
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Irit Huber
- The Sohnis Family Laboratory for Cardiac Electrophysiology and Regenerative Medicine, Rappaport Faculty of Medicine and Research Institute, Technion—Israel Institute of Technology, Haifa 3109601, Israel; (I.H.); (L.G.)
| | - Ingeborg van der Made
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Anouk van den Bout
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Dylan K. de Vries
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Lior Gepstein
- The Sohnis Family Laboratory for Cardiac Electrophysiology and Regenerative Medicine, Rappaport Faculty of Medicine and Research Institute, Technion—Israel Institute of Technology, Haifa 3109601, Israel; (I.H.); (L.G.)
| | - Arie O. Verkerk
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
- Department of Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands;
| | - Yigal M. Pinto
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Anke J. Tijsen
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
- Correspondence: ; Tel.: +31-205668544
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11
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Bassey K, Okpokowuruk FS. Post native uvulo-tonsillectomy hemorrhage as a cause of acquired long QT syndrome in a Nigerian girl: A case report. Niger J Clin Pract 2022; 25:1196-1198. [DOI: 10.4103/njcp.njcp_1941_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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12
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Sheikhy A, Fallahzadeh A, Aghaei Meybodi HR, Hasanzad M, Tajdini M, Hosseini K. Personalized medicine in cardiovascular disease: review of literature. J Diabetes Metab Disord 2021; 20:1793-1805. [PMID: 34900826 DOI: 10.1007/s40200-021-00840-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 06/18/2021] [Indexed: 12/13/2022]
Abstract
Purpose Personalized medicine (PM) is the concept of managing patients based on their characteristics, including genotypes. In the field of cardiology, advantages of PM could be found in the diagnosis and treatment of several conditions such as arrhythmias and cardiomyopathies; moreover, it may be beneficial to prevent adverse drug reactions (ADR) and select the best medication. Genetic background can help us in selecting effective treatments, appropriate dose requirements, and preventive strategies in individuals with particular genotypes. Method In this review, we provide examples of personalized medicine based on human genetics for the most used pharmaceutics in cardiology, including warfarin, clopidogrel, and statins. We also review cardiovascular diseases, including coronary artery disease, arrhythmia, and cardiomyopathies. Conclusion Genetic factors are as important as environmental factors and they should be tested and evaluated more in the future by improving in genetic testing tools. Supplementary Information The online version contains supplementary material available at 10.1007/s40200-021-00840-0.
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Affiliation(s)
- Ali Sheikhy
- Research Department, Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Aida Fallahzadeh
- Research Department, Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Hamid Reza Aghaei Meybodi
- Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Mandana Hasanzad
- Personalized Medicine Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran
- Medical Genomics Research Center, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Masih Tajdini
- Cardiology Department, Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Kaveh Hosseini
- Cardiology Department, Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran
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13
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Wang M, Peterson DR, Rosero S, McNitt S, Rich DQ, Seplaki CL, Polonsky B, Goldenberg I, Zareba W. Effectiveness of Implantable Cardioverter-Defibrillators to Reduce Mortality in Patients With Long QT Syndrome. J Am Coll Cardiol 2021; 78:2076-2088. [PMID: 34794689 DOI: 10.1016/j.jacc.2021.09.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/06/2021] [Accepted: 09/01/2021] [Indexed: 11/25/2022]
Abstract
BACKGROUND The effectiveness of implantable cardioverter-defibrillators (ICDs) on reducing mortality has not been well studied in patients with long QT syndrome (LQTS). OBJECTIVES This study aimed to assess the survival benefits of ICDs in the overall LQTS population and in subgroups defined by ICD indications. METHODS This study included 3,035 patients (597 with ICD) from the Rochester LQTS Registry with a QTc ≥470 milliseconds or confirmed LQTS mutation. Using multivariable Cox proportional hazards models, the risk of all-cause mortality, all-cause mortality before age 50 years, and sudden cardiac death (SCD) were estimated as functions of time-dependent ICD therapy. Indication subgroups examined included patients with: 1) nonfatal cardiac arrest; 2) syncope while on beta-blockers; and 3) a QTc ≥500 milliseconds and syncope while off beta-blockers. RESULTS During the 118,837 person-years of follow-up, 389 patients died (137 before age 50 years, and 116 experienced SCD). In the entire population, patients with ICDs had a lower risk of death (HR: 0.54; 95% CI: 0.34-0.86), death before age 50 years (HR: 0.29; 95% CI: 0.14-0.61), and SCD (HR: 0.22; 95% CI: 0.09-0.55) than patients without ICDs did. Patients with ICDs also had a lower risk of mortality among the 3 indication subgroups (HR: 0.14; 95% CI: 0.06-0.34; HR: 0.27; 95% CI: 0.10-0.72; and HR: 0.42; 95% CI: 0.19-0.96, respectively). CONCLUSIONS ICD therapy was associated with a lower risk of all-cause mortality, all-cause mortality before age 50 years, and SCD in the LQTS population, as wells as with a lower risk of all-cause mortality in indication subgroups. This study provides evidence supporting ICD implantation in patients with high-risk LQTS.
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Affiliation(s)
- Meng Wang
- Clinical Cardiovascular Research Center, Division of Cardiology, University of Rochester Medical Center, Rochester, New York, USA; Division of Epidemiology, Department of Public Health Sciences, University of Rochester Medical Center, Rochester, New York, USA
| | - Derick R Peterson
- Department of Biostatistics and Computational Biology, University of Rochester Medical Center, Rochester, New York, USA
| | - Spencer Rosero
- Division of Cardiology, University of Rochester Medical Center, Rochester, New York, USA
| | - Scott McNitt
- Clinical Cardiovascular Research Center, Division of Cardiology, University of Rochester Medical Center, Rochester, New York, USA
| | - David Q Rich
- Division of Epidemiology, Department of Public Health Sciences, University of Rochester Medical Center, Rochester, New York, USA; Division of Pulmonary and Critical Care, Department of Medicine, University of Rochester Medical Center, Rochester, New York, USA; Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York, USA
| | - Christopher L Seplaki
- Division of Epidemiology, Department of Public Health Sciences, University of Rochester Medical Center, Rochester, New York, USA; Department of Psychiatry, University of Rochester Medical Center, Rochester, New York, USA
| | - Bronislava Polonsky
- Clinical Cardiovascular Research Center, Division of Cardiology, University of Rochester Medical Center, Rochester, New York, USA
| | - Ilan Goldenberg
- Clinical Cardiovascular Research Center, Division of Cardiology, University of Rochester Medical Center, Rochester, New York, USA
| | - Wojciech Zareba
- Clinical Cardiovascular Research Center, Division of Cardiology, University of Rochester Medical Center, Rochester, New York, USA.
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14
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Olgar Y, Durak A, Bitirim CV, Tuncay E, Turan B. Insulin acts as an atypical KCNQ1/KCNE1-current activator and reverses long QT in insulin-resistant aged rats by accelerating the ventricular action potential repolarization through affecting the β 3 -adrenergic receptor signaling pathway. J Cell Physiol 2021; 237:1353-1371. [PMID: 34632595 DOI: 10.1002/jcp.30597] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 09/22/2021] [Accepted: 09/24/2021] [Indexed: 12/13/2022]
Abstract
Insufficient-heart function is associated with myocardial insulin resistance in the elderly, particularly associated with long-QT, in a dependency on dysfunctional KCNQ1/KCNE1-channels. So, we aimed to examine the contribution of alterations in KCNQ1/KCNE1-current (IKs ) to the aging-related remodeling of the heart as well as the role of insulin treatment on IKs in the aged rats. Prolonged late-phase action potential (AP) repolarization of ventricular cardiomyocytes from insulin-resistant 24-month-old rats was significantly reversed by in vitro treatment of insulin or PKG inhibitor (in vivo, as well) via recovery in depressed IKs . Although the protein level of either KCNQ1 or KCNE1 in cardiomyocytes was not affected with aging, PKG level was significantly increased in those cells. The inhibited IKs in β3 -ARs-stimulated cells could be reversed with a PKG inhibitor, indicating the correlation between PKG-activation and β3 -ARs activation. Furthermore, in vivo treatment of aged rats, characterized by β3 -ARs activation, with either insulin or a PKG inhibitor for 2 weeks provided significant recoveries in IKs , prolonged late phases of APs, prolonged QT-intervals, and low heart rates without no effect on insulin resistance. In vivo insulin treatment provided also significant recovery in increased PKG and decreased PIP2 level, without the insulin effect on the KCNQ1 level in β3 -ARs overexpressed cells. The inhibition of IKs in aged-rat cardiomyocytes seems to be associated with activated β3 -ARs dependent remodeling in the interaction between KCNQ1 and KCNE1. Significant recoveries in ventricular-repolarization of insulin-treated aged cardiomyocytes via recovery in IKs strongly emphasize two important issues: (1) IKs can be a novel target in aging-associated remodeling in the heart and insulin may be a cardioprotective agent in the maintenance of normal heart function during the aging process. (2) This study is one of the first to demonstrate insulin's benefits on long-QT in insulin-resistant aged rats by accelerating the ventricular AP repolarization through reversing the depressed IKs via affecting the β3 -ARs signaling pathway and particularly affecting activated PKG.
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Affiliation(s)
- Yusuf Olgar
- Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey
| | - Aysegul Durak
- Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey
| | | | - Erkan Tuncay
- Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey
| | - Belma Turan
- Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey.,Department of Biophysics, Faculty of Medicine, Lokman Hekim University, Ankara, Turkey
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15
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Proshlyakov AY, Chomakhidze PS, Novikova NA. Comparative Characteristics of Beta-Blockers in Patients with Congenital Long QT Syndrome. RATIONAL PHARMACOTHERAPY IN CARDIOLOGY 2021. [DOI: 10.20996/1819-6446-2021-06-19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Congenital long QT syndrome is a pathology that requires special attention and knowledge about the safety and effectiveness of various medications. Prolongation of the QT interval due to congenital or acquired causes is an important factor in the development of an unfavorable life forecast with the formation of an elongated QT syndrome. With an unfavorable course, patients suffer from loss of consciousness, episodes of tachycardia. Often, stable polymorphic ventricular tachycardia develops. The risk of sudden cardiac death in this pathology can vary from 0.33% to 5%. In people who have suffered an episode of cardiac arrest, and do not have a permanent prescribed antiarrhythmic therapy, the mortality rate reaches 50% within 15 years. Preventive administration of antiarrhythmic drugs is not always effective. A positive result of treatment depends on the severity of long QT syndrome and its genotype. Beta-blockers are often prescribed to patients of different ages with various cardiac pathologies, including for the prevention of arrhythmia in long QT syndrome. Beta-blockers differ in various pharmacokinetic and pharmacodynamic parameters (lipophilicity/hydrophilicity, selectivity, presence/absence of internal sympathomimetic activity), which, along with the variant of the disease genotype, can affect their effectiveness and safety in the considered pathology. This review article presents the results of major studies on the safety and effectiveness of different groups of beta blockers in various variants of long QT syndrome. The preferred beta-blockers for various genotypes of the syndrome were determined, and a comparative characteristic of beta-blockers for their safety and preventive effectiveness was given.
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Affiliation(s)
- A. Yu. Proshlyakov
- I.M. Sechenov First Moscow State Medical University (Sechenov University)
| | - P. Sh. Chomakhidze
- I.M. Sechenov First Moscow State Medical University (Sechenov University)
| | - N. A. Novikova
- I.M. Sechenov First Moscow State Medical University (Sechenov University)
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16
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Molecular Mechanism of Autosomal Recessive Long QT-Syndrome 1 without Deafness. Int J Mol Sci 2021; 22:ijms22031112. [PMID: 33498651 PMCID: PMC7865240 DOI: 10.3390/ijms22031112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/16/2021] [Accepted: 01/19/2021] [Indexed: 11/16/2022] Open
Abstract
KCNQ1 encodes the voltage-gated potassium (Kv) channel KCNQ1, also known as KvLQT1 or Kv7.1. Together with its ß-subunit KCNE1, also denoted as minK, this channel generates the slowly activating cardiac delayed rectifier current IKs, which is a key regulator of the heart rate dependent adaptation of the cardiac action potential duration (APD). Loss-of-function mutations in KCNQ1 cause congenital long QT1 (LQT1) syndrome, characterized by a delayed cardiac repolarization and a prolonged QT interval in the surface electrocardiogram. Autosomal dominant loss-of-function mutations in KCNQ1 result in long QT syndrome, called Romano–Ward Syndrome (RWS), while autosomal recessive mutations lead to Jervell and Lange-Nielsen syndrome (JLNS), associated with deafness. Here, we identified a homozygous KCNQ1 mutation, c.1892_1893insC (p.P631fs*20), in a patient with an isolated LQT syndrome (LQTS) without hearing loss. Nevertheless, the inheritance trait is autosomal recessive, with heterozygous family members being asymptomatic. The results of the electrophysiological characterization of the mutant, using voltage-clamp recordings in Xenopus laevis oocytes, are in agreement with an autosomal recessive disorder, since the IKs reduction was only observed in homomeric mutants, but not in heteromeric IKs channel complexes containing wild-type channel subunits. We found that KCNE1 rescues the KCNQ1 loss-of-function in mutant IKs channel complexes when they contain wild-type KCNQ1 subunits, as found in the heterozygous state. Action potential modellings confirmed that the recessive c.1892_1893insC LQT1 mutation only affects the APD of homozygous mutation carriers. Thus, our study provides the molecular mechanism for an atypical autosomal recessive LQT trait that lacks hearing impairment.
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17
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Han L, Liu F, Li Q, Qing T, Zhai Z, Xia Z, Li J. The Efficacy of Beta-Blockers in Patients With Long QT Syndrome 1-3 According to Individuals' Gender, Age, and QTc Intervals: A Network Meta-analysis. Front Pharmacol 2021; 11:579525. [PMID: 33381033 PMCID: PMC7768040 DOI: 10.3389/fphar.2020.579525] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 11/13/2020] [Indexed: 02/02/2023] Open
Abstract
Long QT syndrome (LQTS) is an arrhythmic heart disease caused by congenital genetic mutations, and results in increased occurrence rates of polymorphic ventricular tachyarrhythmias and sudden cardiac death (SCD). Clinical evidence from numerous previous studies suggested that beta blockers (BBs), including atenolol, propranolol, metoprolol, and nadolol, exhibit different efficacies for reducing the risk of cardiac events (CEs), such as syncope, arrest cardiac arrest (ACA), and SCD, in patients with LQTS. In this study, we identified relevant studies in MEDLINE, PubMed, embase, and Cochrane databases and performed a meta-analysis to assess the relationship between the rate of CEs and LQTS individuals with confounding variables, including different gender, age, and QTc intervals. Moreover, a network meta-analysis was not only established to evaluate the effectiveness of different BBs, but also to provide the ranked efficacies of BBs treatment for preventing the recurrence of CEs in LQT1 and LQT2 patients. In conclusion, nadolol was recommended as a relatively effective strategy for LQT2 in order to improve the prognosis of patients during a long follow-up period.
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Affiliation(s)
- Lu Han
- Department of Cardiovascular Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Fuxiang Liu
- Department of Cardiovascular Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Qing Li
- Department of Cardiovascular Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Tao Qing
- Department of Cardiovascular Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Zhenyu Zhai
- Department of Cardiovascular Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Zirong Xia
- Department of Cardiovascular Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Juxiang Li
- Department of Cardiovascular Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang, China
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18
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Dahlberg P, Diamant UB, Gilljam T, Rydberg A, Bergfeldt L. QT correction using Bazett's formula remains preferable in long QT syndrome type 1 and 2. Ann Noninvasive Electrocardiol 2020; 26:e12804. [PMID: 33070409 PMCID: PMC7816807 DOI: 10.1111/anec.12804] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 08/27/2020] [Accepted: 08/31/2020] [Indexed: 11/28/2022] Open
Abstract
Background The heart rate (HR) corrected QT interval (QTc) is crucial for diagnosis and risk stratification in the long QT syndrome (LQTS). Although its use has been questioned in some contexts, Bazett's formula has been applied in most diagnostic and prognostic studies in LQTS patients. However, studies on which formula eliminates the inverse relation between QT and HR are lacking in LQTS patients. We therefore determined which QT correction formula is most appropriate in LQTS patients including the effect of beta blocker therapy and an evaluation of the agreement of the formulae when applying specific QTc limits for diagnostic and prognostic purposes. Methods Automated measurements from routine 12‐lead ECGs from 200 genetically confirmed LQTS patients from two Swedish regions were included (167 LQT1, 33 LQT2). QT correction was performed using the Bazett, Framingham, Fridericia, and Hodges formulae. Linear regression was used to compare the formulae in all patients, and before and after the initiation of beta blocking therapy in a subgroup (n = 44). Concordance analysis was performed for QTc ≥ 480 ms (diagnosis) and ≥500 ms (prognosis). Results The median age was 32 years (range 0.1–78), 123 (62%) were female and 52 (26%) were children ≤16 years. Bazett's formula was the only method resulting in a QTc without relation with HR. Initiation of beta blocking therapy did not alter the result. Concordance analyses showed clinically significant differences (Cohen's kappa 0.629–0.469) for diagnosis and prognosis in individual patients. Conclusion Bazett's formula remains preferable for diagnosis and prognosis in LQT1 and 2 patients.
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Affiliation(s)
- Pia Dahlberg
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Region Västra Götaland, Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Ulla-Britt Diamant
- Department of Public Health and Clinical Medicine, Heart Centre, Umeå University, Umeå, Sweden
| | - Thomas Gilljam
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Region Västra Götaland, Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Annika Rydberg
- Department of Clinical Sciences, Pediatrics, Umeå University, Umeå, Sweden
| | - Lennart Bergfeldt
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Region Västra Götaland, Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden
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19
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Abdelsayed M, Bytyçi I, Rydberg A, Henein MY. Left Ventricular Contraction Duration Is the Most Powerful Predictor of Cardiac Events in LQTS: A Systematic Review and Meta-Analysis. J Clin Med 2020; 9:jcm9092820. [PMID: 32878246 PMCID: PMC7565502 DOI: 10.3390/jcm9092820] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 08/21/2020] [Accepted: 08/26/2020] [Indexed: 02/07/2023] Open
Abstract
Background: Long-QT syndrome (LQTS) is primarily an electrical disorder characterized by a prolonged myocardial action potential. The delay in cardiac repolarization leads to electromechanical (EM) abnormalities, which adds a diagnostic value for LQTS. Prolonged left ventricular (LV) contraction was identified as a potential risk for arrhythmia. The aim of this meta-analysis was to assess the best predictor of all EM parameters for cardiac events (CEs) in LQTS patients. Methods: We systematically searched all electronic databases up to March 2020, to select studies that assessed the relationship between echocardiographic indices—contraction duration (CD), mechanical dispersion (MD), QRS onset to peak systolic strain (QAoC), and the EM window (EMW); and electrical indices— corrected QT interval (QTC), QTC dispersion, RR interval in relation to CEs in LQTS. This meta-analysis included a total of 1041 patients and 373 controls recruited from 12 studies. Results: The meta-analysis showed that LQTS patients had electrical and mechanical abnormalities as compared to controls—QTC, WMD 72.8; QTC dispersion, WMD 31.7; RR interval, WMD 91.5; CD, WMD 49.2; MD, WMD 15.9; QAoC, WMD 27.8; and EMW, WMD −62.4. These mechanical abnormalities were more profound in symptomatic compared to asymptomatic patients in whom disturbances were already manifest, compared to controls. A CD ≥430 ms had a summary sensitivity (SS) of 71%, specificity of 84%, and diagnostic odds ratio (DOR) >19.5 in predicting CEs. EMW and QTC had a lower accuracy. Conclusions: LQTS is associated with pronounced EM abnormalities, particularly prolonged LV myocardial CD, which is profound in symptomatic patients. These findings highlight the significant role of EM indices like CD in managing LQTS patients.
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Affiliation(s)
- Mena Abdelsayed
- Institute of Public Health and Clinical Medicine, Umeå University, 90187 Umeå, Sweden; (M.A.); (I.B.)
| | - Ibadete Bytyçi
- Institute of Public Health and Clinical Medicine, Umeå University, 90187 Umeå, Sweden; (M.A.); (I.B.)
- Universi College, Bardhosh, 10000 Prishtina, Kosovo
| | - Annika Rydberg
- Department of Clinical Sciences, Pediatrics, Umeå University, 90187 Umeå, Sweden;
| | - Michael Y. Henein
- Institute of Public Health and Clinical Medicine, Umeå University, 90187 Umeå, Sweden; (M.A.); (I.B.)
- Molecular and Clinical Sciences Research Institute, St George University London, SW17 0QT, UK
- Institute of Fluid Dynamics, Brunel University, London UB8 3PH, UK
- Correspondence: ; Tel.: +46-90-785-1431
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20
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Pelli A, Kenttä TV, Junttila MJ, Bergau L, Zabel M, Malik M, Reichlin T, Willems R, Vos MA, Harden M, Friede T, Sticherling C, Huikuri HV. Electrocardiogram as a predictor of survival without appropriate shocks in primary prophylactic ICD patients: A retrospective multi-center study. Int J Cardiol 2020; 309:78-83. [PMID: 32188583 DOI: 10.1016/j.ijcard.2020.03.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 01/05/2020] [Accepted: 03/09/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND Abnormal 12-lead electrocardiogram (ECG) can predict cardiovascular events, including sudden cardiac death. We tested the hypothesis that ECG provides useful information on guiding implantable cardioverter defibrillator (ICD) therapy into individuals with impaired left ventricular ejection fraction (LVEF). METHODS Retrospective data of primary prevention ICD implantations from 14 European centers were gathered. The registry included 5111 subjects of whom 1687 patients had an interpretable pre-implantation ECG available (80.0% male, 63.3 ± 11.4 years). Primary outcome was survival without appropriate ICD shocks or heart transplantation. A low-risk ECG was defined as a combination of ECG variables that were associated with the primary outcome. RESULTS A total of 1224 (72.6%) patients survived the follow-up (2.9 ± 1.7 years) without an ICD shock, 224 (13.3%) received an appropriate shock and 260 (15.4%) died. Low-risk ECG defined as QRS duration <120 ms, QTc interval <450 ms for men and <470 ms for women, and sinus rhythm, were met by 515 patients (30.5%). Multivariable Cox regression showed that the hazard (HR) for death, heart transplantation or appropriate shock were reduced by 42.5% in the low-risk group (HR 0.575; 95% CI 0.45-0.74; p < 0.001), compared to the high-risk group. The HR for the first appropriate shock was 42.1% lower (HR 0.58; 95% CI 0.41-0.82; p = 0.002) and the HR for death was 48.0% lower (HR 0.52; 95% CI 0.386-0.72; p < 0.001) in the low-risk group. CONCLUSION Sinus rhythm, QRS <120 ms and normal QTc in standard 12-lead ECG provides information about survival without appropriate ICD shocks and might improve patient selection for primary prevention ICD therapy.
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Affiliation(s)
- Ari Pelli
- Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland
| | - Tuomas V Kenttä
- Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland
| | - M Juhani Junttila
- Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland
| | - Leonard Bergau
- University Medical Center Göttingen Heart Center, Division of Cardiology, Göttingen, Germany
| | - Markus Zabel
- University Medical Center Göttingen Heart Center, Division of Cardiology, Göttingen, Germany; DZHK (German Center for Cardiovascular Research), partner site Göttingen, Göttingen, Germany
| | - Marek Malik
- National Heart and Lung Institute, Imperial College, London, United Kingdom
| | - Tobias Reichlin
- University Hospital Basel, Basel, Division of Cardiology, Switzerland; Department of Cardiology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Rik Willems
- Department of Cardiovascular Sciences, University of Leuven and University Hospitals Leuven, Leuven, Belgium
| | - Marc A Vos
- Medical Physiology, University Medical Center Utrecht, the Netherlands
| | - Markus Harden
- Department of Medical Statistics, University Medical Center Göttingen, Göttingen, Germany
| | - Tim Friede
- Department of Medical Statistics, University Medical Center Göttingen, Göttingen, Germany; DZHK (German Center for Cardiovascular Research), partner site Göttingen, Göttingen, Germany
| | | | - Heikki V Huikuri
- Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland.
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Hardy JR, Bundock D, Cross J, Gibbons K, Pinkerton R, Kindl K, Good P, Philip J. Prevalence of QTc Prolongation in Patients With Advanced Cancer Receiving Palliative Care-A Cause for Concern? J Pain Symptom Manage 2020; 59:856-863. [PMID: 31866486 DOI: 10.1016/j.jpainsymman.2019.12.356] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 12/10/2019] [Accepted: 12/11/2019] [Indexed: 11/18/2022]
Abstract
CONTEXT Medications commonly used for symptom control along with other known risk factors have the potential to prolong ventricular repolarization as measured by the QT interval (the time from the start of the Q wave to the end of the T wave) on a standard electrocardiogram (ECG). OBJECTIVES To document the prevalence of a prolonged QT interval corrected for heart rate (QTc) interval in the palliative/oncology setting, compare automatic ECG QTc measurements with manual readings and identify any correlation between QTc prolongation and the use of drugs or other risk factors. METHODS A convenience sample of consecutive patients with cancer, admitted under or known to the palliative/supportive care teams in two metropolitan hospitals, and willing to provide an ECG recording and basic demographic information including QTc risk factors were included. Both automated and manually calculated QTc intervals were recorded. Multivariable analysis was used to determine risk factors independently associated with prolonged QTc intervals. RESULTS Of the 389 participants, there was a significant difference in mean QTc between sites using automated but not manual calculations. Manual readings were therefore used with predetermined cutoffs of 0.44 seconds (males) and 0.46 seconds (females). Seventy-two (18.5%) of the participants had a prolonged QTc with six (1.5%) having a prolongation of >0.50 seconds. At-risk drugs were being taken by 218 participants (56.0% of total cohort). Factors shown to be associated with QTc prolongation included age, gender, performance status, and hypocalcemia. No specific medication was associated with increased risk. CONCLUSION Although almost 20% of patients receiving palliative care had prolongation of QTc, the possibility of serious consequences appeared to be low despite the frequent occurrence of risk factors.
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Affiliation(s)
- Janet R Hardy
- Department of Palliative and Supportive Care, Mater Misericordiae Ltd, South Brisbane, Queensland, Australia; Mater Research Institute - University of Queensland, South Brisbane, Queensland, Australia.
| | - Daniel Bundock
- Department of Palliative and Supportive Care, Mater Misericordiae Ltd, South Brisbane, Queensland, Australia
| | - Jessica Cross
- Department of Palliative and Supportive Care, Mater Misericordiae Ltd, South Brisbane, Queensland, Australia
| | - Kristen Gibbons
- Mater Research Institute - University of Queensland, South Brisbane, Queensland, Australia
| | - Ross Pinkerton
- Hummingbird House Hospice, Chermside, Queensland, Australia
| | - Korana Kindl
- St Vincent's Private Hospital Brisbane, Kangaroo Point, Queensland, Australia
| | - Phillip Good
- Department of Palliative and Supportive Care, Mater Misericordiae Ltd, South Brisbane, Queensland, Australia; Mater Research Institute - University of Queensland, South Brisbane, Queensland, Australia; St Vincent's Private Hospital Brisbane, Kangaroo Point, Queensland, Australia
| | - Jennifer Philip
- University of Melbourne and St. Vincent's Hospital, Melbourne, Victoria, Australia
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Virani SS, Alonso A, Benjamin EJ, Bittencourt MS, Callaway CW, Carson AP, Chamberlain AM, Chang AR, Cheng S, Delling FN, Djousse L, Elkind MSV, Ferguson JF, Fornage M, Khan SS, Kissela BM, Knutson KL, Kwan TW, Lackland DT, Lewis TT, Lichtman JH, Longenecker CT, Loop MS, Lutsey PL, Martin SS, Matsushita K, Moran AE, Mussolino ME, Perak AM, Rosamond WD, Roth GA, Sampson UKA, Satou GM, Schroeder EB, Shah SH, Shay CM, Spartano NL, Stokes A, Tirschwell DL, VanWagner LB, Tsao CW. Heart Disease and Stroke Statistics-2020 Update: A Report From the American Heart Association. Circulation 2020; 141:e139-e596. [PMID: 31992061 DOI: 10.1161/cir.0000000000000757] [Citation(s) in RCA: 4766] [Impact Index Per Article: 1191.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND The American Heart Association, in conjunction with the National Institutes of Health, annually reports on the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs). METHODS The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2020 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, metrics to assess and monitor healthy diets, an enhanced focus on social determinants of health, a focus on the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors, implementation strategies, and implications of the American Heart Association's 2020 Impact Goals. RESULTS Each of the 26 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics. CONCLUSIONS The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, healthcare administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.
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23
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Benjamin EJ, Muntner P, Alonso A, Bittencourt MS, Callaway CW, Carson AP, Chamberlain AM, Chang AR, Cheng S, Das SR, Delling FN, Djousse L, Elkind MSV, Ferguson JF, Fornage M, Jordan LC, Khan SS, Kissela BM, Knutson KL, Kwan TW, Lackland DT, Lewis TT, Lichtman JH, Longenecker CT, Loop MS, Lutsey PL, Martin SS, Matsushita K, Moran AE, Mussolino ME, O'Flaherty M, Pandey A, Perak AM, Rosamond WD, Roth GA, Sampson UKA, Satou GM, Schroeder EB, Shah SH, Spartano NL, Stokes A, Tirschwell DL, Tsao CW, Turakhia MP, VanWagner LB, Wilkins JT, Wong SS, Virani SS. Heart Disease and Stroke Statistics-2019 Update: A Report From the American Heart Association. Circulation 2019; 139:e56-e528. [PMID: 30700139 DOI: 10.1161/cir.0000000000000659] [Citation(s) in RCA: 5247] [Impact Index Per Article: 1049.4] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Alahmadi A, Davies A, Vigo M, Jay C. Can laypeople identify a drug-induced QT interval prolongation? A psychophysical and eye-tracking experiment examining the ability of nonexperts to interpret an ECG. J Am Med Inform Assoc 2019; 26:404-411. [PMID: 30848818 PMCID: PMC7787352 DOI: 10.1093/jamia/ocy183] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 11/22/2018] [Accepted: 12/10/2018] [Indexed: 01/10/2023] Open
Abstract
Objective The study sought to quantify a layperson’s ability to detect drug-induced QT interval prolongation on an electrocardiogram (ECG) and determine whether the presentation of the trace affects such detection. Materials and Methods Thirty layperson participants took part in a psychophysical and eye-tracking experiment. Following training, participants completed 21 experimental trials, in which each trial consisted of 2 ECGs (a baseline and a comparison stimulus, both with a heart rate of 60 beats/min). The experiment used a 1 alternative forced-choice paradigm, in which participants indicated whether or not they perceived a difference in the QT interval length between the 2 ECGs. The ECG trace was presented in 3 ways: a single complex with the signals aligned by the R wave, a single complex without alignment, and a 10-second rhythm strip. Performance was analyzed using the psychometric function to estimate the just noticeable difference threshold, along with eye-tracking metrics. Results The just noticeable difference 50% and 75% thresholds were 30 and 88 ms, respectively, showing that the majority of laypeople were able to detect a clinically significant QT-prolongation at a low normal heart rate. Eye movement data indicated that people were more likely to appraise the rhythm strip stimulus systematically and accurately. Conclusions People can quickly be trained to self-monitor, which may help with more rapid identification of drug-induced long QT syndrome and prevent the development of life-threatening complications. The rhythm strip is a better form of presentation than a single complex, as it is less likely to be misinterpreted due to artifacts in the signal.
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Affiliation(s)
- Alaa Alahmadi
- University of Manchester, School of Computer Science, Manchester, UK
| | - Alan Davies
- University of Manchester, School of Computer Science, Manchester, UK
| | - Markel Vigo
- University of Manchester, School of Computer Science, Manchester, UK
| | - Caroline Jay
- University of Manchester, School of Computer Science, Manchester, UK
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25
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Singh M, Morin DP, Link MS. Sudden cardiac death in Long QT syndrome (LQTS), Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia (CPVT). Prog Cardiovasc Dis 2019; 62:227-234. [DOI: 10.1016/j.pcad.2019.05.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 05/06/2019] [Indexed: 10/26/2022]
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Churet M, Luttoo K, Hocini M, Haïssaguerre M, Sacher F, Duchateau J. Diagnostic reproducibility of epinephrine drug challenge interpretation in suspected long QT syndrome. J Cardiovasc Electrophysiol 2019; 30:896-901. [DOI: 10.1111/jce.13926] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 03/06/2019] [Accepted: 03/09/2019] [Indexed: 11/28/2022]
Affiliation(s)
- Maxime Churet
- Department of Cardiology‐Cardiac Electrophysiology and PacingBordeaux University HospitalBordeaux France
| | - Khaled Luttoo
- Department of Cardiology‐Cardiac Electrophysiology and PacingBordeaux University HospitalBordeaux France
| | - Mélèze Hocini
- Department of Cardiology‐Cardiac Electrophysiology and PacingBordeaux University HospitalBordeaux France
| | - Michel Haïssaguerre
- Department of Cardiology‐Cardiac Electrophysiology and PacingBordeaux University HospitalBordeaux France
| | - Frédéric Sacher
- Department of Cardiology‐Cardiac Electrophysiology and PacingBordeaux University HospitalBordeaux France
| | - Josselin Duchateau
- Department of Cardiology‐Cardiac Electrophysiology and PacingBordeaux University HospitalBordeaux France
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Abstract
The development of the reprogramming technology led to generation of induced Pluripotent Stem Cells (iPSC) from a variety of somatic cells. Ever since, fast growing knowledge of different efficient protocols enabled the differentiation of these iPSCs into different cells types utilized for disease modeling. Indeed, iPSC-derived cells have been increasingly used for investigating molecular and cellular pathophysiological mechanisms underlying inherited diseases. However, a major barrier in the field of iPSC-based disease modeling relies on discriminating between the effects of the causative mutation and the genetic background of these cells. In the past decade, researchers have made great improvement in genome editing techniques, with one of the latest being CRISPR/Cas9. Using a single non-sequence specific protein combined with a small guiding RNA molecule, this state-of-the-art approach enables modifications of genes with high efficiency and accuracy. By so doing, this technique enables the generation of isogenic controls or isogenic mutated cell lines in order to focus on the pathologies caused by a specific mutation. In this article, we review the latest studies combining iPSC and CRISPR/Cas9 technologies for the investigation of the molecular and cellular mechanisms underlying inherited diseases including immunological, metabolic, hematological, neurodegenerative and cardiac diseases.
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Li K, Yang J, Guo W, Lv T, Guo J, Li J, Zhang P. Video-Assisted Thoracoscopic Left Cardiac Sympathetic Denervation in Chinese Patients with Long QT Syndrome. Int Heart J 2018; 59:1346-1351. [DOI: 10.1536/ihj.17-727] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Kun Li
- School of Clinical Medicine, Tsinghua University
| | - Jing Yang
- Department of Cardiology, Beijing Tsinghua Changgung Hospital
| | - Wenjia Guo
- School of Clinical Medicine, Tsinghua University
| | - Tingting Lv
- School of Clinical Medicine, Tsinghua University
| | - Jihong Guo
- Department of Cardiology, Peking University People's Hospital
| | - Jianfeng Li
- Department of Cardiology, Peking University People's Hospital
| | - Ping Zhang
- School of Clinical Medicine, Tsinghua University
- Department of Cardiology, Beijing Tsinghua Changgung Hospital
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30
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Landaw J, Qu Z. Memory-induced nonlinear dynamics of excitation in cardiac diseases. Phys Rev E 2018; 97:042414. [PMID: 29758700 DOI: 10.1103/physreve.97.042414] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Indexed: 11/07/2022]
Abstract
Excitable cells, such as cardiac myocytes, exhibit short-term memory, i.e., the state of the cell depends on its history of excitation. Memory can originate from slow recovery of membrane ion channels or from accumulation of intracellular ion concentrations, such as calcium ion or sodium ion concentration accumulation. Here we examine the effects of memory on excitation dynamics in cardiac myocytes under two diseased conditions, early repolarization and reduced repolarization reserve, each with memory from two different sources: slow recovery of a potassium ion channel and slow accumulation of the intracellular calcium ion concentration. We first carry out computer simulations of action potential models described by differential equations to demonstrate complex excitation dynamics, such as chaos. We then develop iterated map models that incorporate memory, which accurately capture the complex excitation dynamics and bifurcations of the action potential models. Finally, we carry out theoretical analyses of the iterated map models to reveal the underlying mechanisms of memory-induced nonlinear dynamics. Our study demonstrates that the memory effect can be unmasked or greatly exacerbated under certain diseased conditions, which promotes complex excitation dynamics, such as chaos. The iterated map models reveal that memory converts a monotonic iterated map function into a nonmonotonic one to promote the bifurcations leading to high periodicity and chaos.
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Affiliation(s)
- Julian Landaw
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA and Department of Biomathematics, University of California, Los Angeles, California 90095, USA
| | - Zhilin Qu
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA and Department of Biomathematics, University of California, Los Angeles, California 90095, USA
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Muresan L, Cismaru G, Martins RP, Bataglia A, Rosu R, Puiu M, Gusetu G, Mada RO, Muresan C, Ispas DR, Le Bouar R, Diene LL, Rugina E, Levy J, Klein C, Sellal JM, Poull IM, Laurent G, de Chillou C. Recommendations for the use of electrophysiological study: Update 2018. Hellenic J Cardiol 2018; 60:82-100. [PMID: 30278230 DOI: 10.1016/j.hjc.2018.09.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 08/31/2018] [Accepted: 09/24/2018] [Indexed: 12/16/2022] Open
Abstract
The field of cardiac electrophysiology has greatly developed during the past decades. Consequently, the use of electrophysiological studies (EPSs) in clinical practice has also significantly augmented, with a progressively increasing number of certified electrophysiology centers and specialists. Since Zipes et al published the Guidelines for Clinical Intracardiac Electrophysiology and Catheter Ablation Procedures in 1995, no official document summarizing current EPS indications has been published. The current paper focuses on summarizing all relevant data of the role of EPS in patients with different types of cardiac pathologies and provides up-to-date recommendations on this topic. For this purpose, the PubMed database was screened for relevant articles in English up to December 2018 and ESC and ACC/AHA Clinical Practice Guidelines, and EHRA/HRS/APHRS position statements related to the current topic were analyzed. Current recommendations for the use of EPS in clinical practice are discussed and presented in 17 distinct cardiac pathologies. A short rationale, evidence, and indications are provided for each cardiac disease/group of diseases. In conclusion, because of its capability to establish a diagnosis in patients with a variety of cardiac pathologies, the EPS remains a useful tool in the evaluation of patients with cardiac arrhythmias and conduction disorders and is capable of establishing indications for cardiac device implantation and guide catheter ablation procedures.
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Affiliation(s)
- Lucian Muresan
- "Emile Muller" Hospital, Cardiology Department, 68100 Mulhouse, France.
| | - Gabriel Cismaru
- Rehabilitation Hospital, Cardiology Department, 400347 Cluj-Napoca, Romania
| | - Raphaël Pedro Martins
- Centre Hospitalier Universitaire de Rennes, Cardiology Department, 35000 Rennes, France
| | - Alberto Bataglia
- Institut Lorrain du Coeur et des Vaisseaux « Louis Mathieu », Cardiology Department, Electrophysiology Department, 54000 Vandoeuvre-les-Nancy, France
| | - Radu Rosu
- Rehabilitation Hospital, Cardiology Department, 400347 Cluj-Napoca, Romania
| | - Mihai Puiu
- Rehabilitation Hospital, Cardiology Department, 400347 Cluj-Napoca, Romania
| | - Gabriel Gusetu
- Rehabilitation Hospital, Cardiology Department, 400347 Cluj-Napoca, Romania
| | - Razvan Olimpiu Mada
- "Niculae Stancioiu" Heart Institute, Cardiology Department, 400005 Cluj-Napoca, Romania
| | - Crina Muresan
- "Emile Muller" Hospital, Cardiology Department, 68100 Mulhouse, France
| | - Daniel Radu Ispas
- Rehabilitation Hospital, Cardiology Department, 400347 Cluj-Napoca, Romania
| | - Ronan Le Bouar
- "Emile Muller" Hospital, Cardiology Department, 68100 Mulhouse, France
| | | | - Elena Rugina
- "Emile Muller" Hospital, Cardiology Department, 68100 Mulhouse, France
| | - Jacques Levy
- "Emile Muller" Hospital, Cardiology Department, 68100 Mulhouse, France
| | - Cedric Klein
- Centre Hospitalier Universitaire de Lille, Cardiology Department, 59000 Lille, France
| | - Jean Marc Sellal
- Institut Lorrain du Coeur et des Vaisseaux « Louis Mathieu », Cardiology Department, Electrophysiology Department, 54000 Vandoeuvre-les-Nancy, France
| | - Isabelle Magnin Poull
- Institut Lorrain du Coeur et des Vaisseaux « Louis Mathieu », Cardiology Department, Electrophysiology Department, 54000 Vandoeuvre-les-Nancy, France
| | - Gabriel Laurent
- Centre Hospitalier Universitaire de Dijon, Cardiology Department, 21000 Dijon, France
| | - Christian de Chillou
- Institut Lorrain du Coeur et des Vaisseaux « Louis Mathieu », Cardiology Department, Electrophysiology Department, 54000 Vandoeuvre-les-Nancy, France
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Elston S, Kaski J, Starling L. Long QT syndrome with a functional 2:1 block and multilevel conduction disease. PROGRESS IN PEDIATRIC CARDIOLOGY 2018. [DOI: 10.1016/j.ppedcard.2018.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Benjamin EJ, Virani SS, Callaway CW, Chamberlain AM, Chang AR, Cheng S, Chiuve SE, Cushman M, Delling FN, Deo R, de Ferranti SD, Ferguson JF, Fornage M, Gillespie C, Isasi CR, Jiménez MC, Jordan LC, Judd SE, Lackland D, Lichtman JH, Lisabeth L, Liu S, Longenecker CT, Lutsey PL, Mackey JS, Matchar DB, Matsushita K, Mussolino ME, Nasir K, O'Flaherty M, Palaniappan LP, Pandey A, Pandey DK, Reeves MJ, Ritchey MD, Rodriguez CJ, Roth GA, Rosamond WD, Sampson UKA, Satou GM, Shah SH, Spartano NL, Tirschwell DL, Tsao CW, Voeks JH, Willey JZ, Wilkins JT, Wu JH, Alger HM, Wong SS, Muntner P. Heart Disease and Stroke Statistics-2018 Update: A Report From the American Heart Association. Circulation 2018; 137:e67-e492. [PMID: 29386200 DOI: 10.1161/cir.0000000000000558] [Citation(s) in RCA: 4474] [Impact Index Per Article: 745.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Wang M, Szepietowska B, Polonsky B, McNitt S, Moss AJ, Zareba W, Auerbach DS. Risk of Cardiac Events Associated With Antidepressant Therapy in Patients With Long QT Syndrome. Am J Cardiol 2018; 121:182-187. [PMID: 29174490 DOI: 10.1016/j.amjcard.2017.10.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 09/26/2017] [Accepted: 10/04/2017] [Indexed: 12/14/2022]
Abstract
Patients with long QT syndrome (LQTS) are at a high risk of cardiac events. Many patients with LQTS are treated with antidepressant drugs (ADs). We investigated the LQTS genotype-specific risk of recurrent cardiac arrhythmic events (CAEs) associated with AD therapy. The study included 59 LQT1 and 72 LQT2 patients from the Rochester-based LQTS Registry with corrected QT (QTc) prolongation and a history of AD therapy. Using multivariate Anderson-Gill models, we estimated the LQTS genotype-specific risk of recurrent CAEs (ventricular tachyarrhythmias, aborted cardiac arrest, or sudden cardiac death) associated with time-dependent ADs. Specifically, we examined the risk associated with all ADs, selective serotonin reuptake inhibitor (SSRI), and ADs classified on the CredibleMeds list (www.CredibleMeds.org) as "Conditional" or "Known risk of Torsades de pointes (TdP)." After adjusting for baseline QTc duration, sex, and time-dependent beta-blocker usage, there was an increased risk of recurrent CAEs associated with ADs in LQT1 patients (hazard ratio = 3.67, 95% confidence interval 1.98-6.82, p < 0.001) but not in LQT2 patients (hazard ratio = 0.89, 95% confidence interval 0.49-1.64, p = 0.716; LQT1 vs LQT2 interaction, p < 0.001). Similarly, LQT1 patients who were on SSRIs or ADs with "Known risk of TdP" had a higher risk of recurrent CAEs than those patients off all ADs, whereas there was no association in LQT2 patients. ADs with "Conditional risk of TdP" were not associated with the risk of recurrent CAEs in any of the groups. In conclusion, the risk of recurrent CAEs associated with time-dependent ADs is higher in LQT1 patients but not in LQT2 patients. Results suggest a LQTS genotype-specific effect of ADs on the risk of arrhythmic events.
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Affiliation(s)
- Meng Wang
- Department of Medicine, Heart Research Follow-up Program, University of Rochester Medical Center, Rochester, New York; Department of Public Health Sciences, University of Rochester Medical Center, Rochester, New York
| | - Barbara Szepietowska
- Department of Medicine, Heart Research Follow-up Program, University of Rochester Medical Center, Rochester, New York
| | - Bronislava Polonsky
- Department of Medicine, Heart Research Follow-up Program, University of Rochester Medical Center, Rochester, New York
| | - Scott McNitt
- Department of Medicine, Heart Research Follow-up Program, University of Rochester Medical Center, Rochester, New York
| | - Arthur J Moss
- Department of Medicine, Heart Research Follow-up Program, University of Rochester Medical Center, Rochester, New York
| | - Wojciech Zareba
- Department of Medicine, Heart Research Follow-up Program, University of Rochester Medical Center, Rochester, New York
| | - David S Auerbach
- Department of Medicine, Aab Cardiovascular Research Institute, University of Rochester Medical Center, Rochester, New York; Department of Pharmacology & Physiology, University of Rochester Medical Center, Rochester, New York.
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Ahn J, Kim HJ, Choi JI, Lee KN, Shim J, Ahn HS, Kim YH. Effectiveness of beta-blockers depending on the genotype of congenital long-QT syndrome: A meta-analysis. PLoS One 2017; 12:e0185680. [PMID: 29059199 PMCID: PMC5653191 DOI: 10.1371/journal.pone.0185680] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 09/17/2017] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Beta-blockers are first-line therapy in patients with congenital long-QT syndrome (LQTS). OBJECTIVE This study sought to determine the differences in effectiveness of beta-blockers on risk reduction according to LQTS genotype. METHODS We searched MEDLINE, EMBASE, and CENTRAL databases to investigate the use of beta-blockers (atenolol, nadolol, propranolol, and metoprolol) in patients with LQTS. Hazard ratio (HR) and relative risk (RR) were extracted or calculated from studies reporting cardiac events (syncope, aborted cardiac arrest (ACA), or sudden cardiac death (SCD)). RESULTS Among 2,113 articles searched, 10 studies (7 registry-based cohort studies (Cohort) and 3 interrupted time series studies (ITS)) involving 9,727 patients were included. In a meta-analysis using a random-effect model, the use of beta-blocker was associated with significant risk reduction of all cardiac events (HR 0.49, p<0.001 in Cohort; RR 0.39, p<0.001 in ITS) and serious cardiac events (ACA or SCD) (HR 0.47, p<0.001 in Cohort). In both LQT1 and LQT2, the risk was reduced with beta-blocker therapy in Cohort (HR 0.59 in LQT1; HR 0.39 in LQT2) as well as ITS (RR 0.29 in LQT1; RR 0.48 in LQT2). Among the beta-blockers, nadolol showed a significant risk reduction in both LQT1 and LQT2 (HR 0.47 and 0.27, respectively), whereas atenolol and propranolol decreased the risk only in LQT1 (HR 0.36 and 0.46, respectively). Metoprolol showed no significant reduction in either genotype. In LQT3, beta-blocker therapy was not as effective as LQT1 or LQT2; however, it was inconclusive due to data insufficiency. CONCLUSION This meta-analysis showed that beta-blockers were effective in reducing risk of cardiac events in patients with LQTS. Among them, nadolol was effective in LQT1 and LQT2, whereas other drugs showed different effectiveness depending on LQT genotype.
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Affiliation(s)
- Jinhee Ahn
- Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Medical Center, Seoul, Republic of Korea
- Division of Cardiology, Department of Internal Medicine, Pusan National University Hospital, Busan, Republic of Korea
| | - Hyun Jung Kim
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Republic of Korea
| | - Jong-Il Choi
- Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Medical Center, Seoul, Republic of Korea
| | - Kwang No Lee
- Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Medical Center, Seoul, Republic of Korea
| | - Jaemin Shim
- Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Medical Center, Seoul, Republic of Korea
| | - Hyeong Sik Ahn
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Republic of Korea
| | - Young-Hoon Kim
- Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Medical Center, Seoul, Republic of Korea
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36
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Wiśniowska B, Tylutki Z, Polak S. Humans Vary, So Cardiac Models Should Account for That Too! Front Physiol 2017; 8:700. [PMID: 28983251 PMCID: PMC5613127 DOI: 10.3389/fphys.2017.00700] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 08/30/2017] [Indexed: 12/25/2022] Open
Abstract
The utilization of mathematical modeling and simulation in drug development encompasses multiple mathematical techniques and the location of a drug candidate in the development pipeline. Historically speaking they have been used to analyze experimental data (i.e., Hill equation) and clarify the involved physical and chemical processes (i.e., Fick laws and drug molecule diffusion). In recent years the advanced utilization of mathematical modeling has been an important part of the regulatory review process. Physiologically based pharmacokinetic (PBPK) models identify the need to conduct specific clinical studies, suggest specific study designs and propose appropriate labeling language. Their application allows the evaluation of the influence of intrinsic (e.g., age, gender, genetics, disease) and extrinsic [e.g., dosing schedule, drug-drug interactions (DDIs)] factors, alone or in combinations, on drug exposure and therefore provides accurate population assessment. A similar pathway has been taken for the assessment of drug safety with cardiac safety being one the most advanced examples. Mechanistic mathematical model-informed safety evaluation, with a focus on drug potential for causing arrhythmias, is now discussed as an element of the Comprehensive in vitro Proarrhythmia Assay. One of the pillars of this paradigm is the use of an in silico model of the adult human ventricular cardiomyocyte to integrate in vitro measured data. Existing examples (in vitro—in vivo extrapolation with the use of PBPK models) suggest that deterministic, epidemiological and clinical data based variability models can be merged with the mechanistic models describing human physiology. There are other methods available, based on the stochastic approach and on population of models generated by randomly assigning specific parameter values (ionic current conductance and kinetic) and further pruning. Both approaches are briefly characterized in this manuscript, in parallel with the drug-specific variability.
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Affiliation(s)
- Barbara Wiśniowska
- Pharmacoepidemiology and Pharmacoeconomics Unit, Faculty of Pharmacy, Jagiellonian University Medical CollegeKrakow, Poland
| | - Zofia Tylutki
- Pharmacoepidemiology and Pharmacoeconomics Unit, Faculty of Pharmacy, Jagiellonian University Medical CollegeKrakow, Poland
| | - Sebastian Polak
- Pharmacoepidemiology and Pharmacoeconomics Unit, Faculty of Pharmacy, Jagiellonian University Medical CollegeKrakow, Poland.,SimcypCertara, Sheffield, United Kingdom
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37
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Bai J, Wang K, Liu Y, Li Y, Liang C, Luo G, Dong S, Yuan Y, Zhang H. Computational Cardiac Modeling Reveals Mechanisms of Ventricular Arrhythmogenesis in Long QT Syndrome Type 8: CACNA1C R858H Mutation Linked to Ventricular Fibrillation. Front Physiol 2017; 8:771. [PMID: 29046645 PMCID: PMC5632762 DOI: 10.3389/fphys.2017.00771] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 09/21/2017] [Indexed: 01/05/2023] Open
Abstract
Functional analysis of the L-type calcium channel has shown that the CACNA1C R858H mutation associated with severe QT interval prolongation may lead to ventricular fibrillation (VF). This study investigated multiple potential mechanisms by which the CACNA1C R858H mutation facilitates and perpetuates VF. The Ten Tusscher-Panfilov (TP06) human ventricular cell models incorporating the experimental data on the kinetic properties of L-type calcium channels were integrated into one-dimensional (1D) fiber, 2D sheet, and 3D ventricular models to investigate the pro-arrhythmic effects of CACNA1C mutations by quantifying changes in intracellular calcium handling, action potential profiles, action potential duration restitution (APDR) curves, dispersion of repolarization (DOR), QT interval and spiral wave dynamics. R858H “mutant” L-type calcium current (ICaL) augmented sarcoplasmic reticulum calcium content, leading to the development of afterdepolarizations at the single cell level and focal activities at the tissue level. It also produced inhomogeneous APD prolongation, causing QT prolongation and repolarization dispersion amplification, rendering R858H “mutant” tissue more vulnerable to the induction of reentry compared with other conditions. In conclusion, altered ICaL due to the CACNA1C R858H mutation increases arrhythmia risk due to afterdepolarizations and increased tissue vulnerability to unidirectional conduction block. However, the observed reentry is not due to afterdepolarizations (not present in our model), but rather to a novel blocking mechanism.
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Affiliation(s)
- Jieyun Bai
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Kuanquan Wang
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Yashu Liu
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Yacong Li
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Cuiping Liang
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Gongning Luo
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Suyu Dong
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Yongfeng Yuan
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Henggui Zhang
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China.,Biological Physics Group, School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom.,Space Institute of Southern China, Shenzhen, China
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38
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Jeevaratnam K, Chadda KR, Salvage SC, Valli H, Ahmad S, Grace AA, Huang CLH. Ion channels, long QT syndrome and arrhythmogenesis in ageing. Clin Exp Pharmacol Physiol 2017; 44 Suppl 1:38-45. [PMID: 28024120 PMCID: PMC5763326 DOI: 10.1111/1440-1681.12721] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 12/18/2016] [Accepted: 12/19/2016] [Indexed: 01/08/2023]
Abstract
Ageing is associated with increased prevalences of both atrial and ventricular arrhythmias, reflecting disruption of the normal sequence of ion channel activation and inactivation generating the propagated cardiac action potential. Experimental models with specific ion channel genetic modifications have helped clarify the interacting functional roles of ion channels and how their dysregulation contributes to arrhythmogenic processes at the cellular and systems level. They have also investigated interactions between these ion channel abnormalities and age-related processes in producing arrhythmic tendency. Previous reviews have explored the relationships between age and loss-of-function Nav 1.5 mutations in producing arrhythmogenicity. The present review now explores complementary relationships arising from gain-of-function Nav 1.5 mutations associated with long QT3 (LQTS3). LQTS3 patients show increased risks of life-threatening ventricular arrhythmias, particularly after 40 years of age, consistent with such interactions between the ion channel abnormailities and ageing. In turn clinical evidence suggests that ageing is accompanied by structural, particularly fibrotic, as well as electrophysiological change. These abnormalities may result from biochemical changes producing low-grade inflammation resulting from increased production of reactive oxygen species and superoxide. Experimental studies offer further insights into the underlying mechanisms underlying these phenotypes. Thus, studies in genetically modified murine models for LQTS implicated action potential recovery processes in arrhythmogenesis resulting from functional ion channel abnormalities. In addition, ageing wild type (WT) murine models demonstrated both ion channel alterations and fibrotic changes with ageing. Murine models then suggested evidence for interactions between ageing and ion channel mutations and provided insights into potential arrhythmic mechanisms inviting future exploration.
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Affiliation(s)
- Kamalan Jeevaratnam
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK.,School of Medicine, Perdana University-Royal College of Surgeons Ireland, Serdang, Selangor Darul Ehsan, Malaysia
| | - Karan R Chadda
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK.,Physiological Laboratory, University of Cambridge, Cambridge, UK
| | | | - Haseeb Valli
- Physiological Laboratory, University of Cambridge, Cambridge, UK
| | - Shiraz Ahmad
- Physiological Laboratory, University of Cambridge, Cambridge, UK
| | - Andrew A Grace
- Division of Cardiovascular Biology, Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Christopher L-H Huang
- Physiological Laboratory, University of Cambridge, Cambridge, UK.,Division of Cardiovascular Biology, Department of Biochemistry, University of Cambridge, Cambridge, UK
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Pourmand A, Mazer-Amirshahi M, Chistov S, Sabha Y, Vukomanovic D, Almulhim M. Emergency department approach to QTc prolongation. Am J Emerg Med 2017; 35:1928-1933. [PMID: 28855066 DOI: 10.1016/j.ajem.2017.08.044] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 08/13/2017] [Accepted: 08/19/2017] [Indexed: 01/08/2023] Open
Abstract
QTc prolongation has been associated with increased risk of developing ventricular tachydysrhythmias, particularly Torsades de Pointes (TdP). QTc prolongation is influenced by many factors including congenital causes, heart rate, metabolic imbalances, and pharmacotherapy. Several commonly used medications in the emergency department (ED), such as antipsychotics and antiemetics, are known to prolong the QT interval. In addition, ED patients may present with conditions that may predispose them to QTc prolongation, such as drug overdose or hypokalemia, which can further complicate management. ED providers should not only be aware of which medications have these effects, but must also thoroughly investigate any pertinent patient history that may contribute to QTc prolongation. This review discusses commonly encountered medications that are associated with QTc prolongation, the mechanisms by which they prolong the QTc interval, and other factors that may influence ED medication administration and management.
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Affiliation(s)
- Ali Pourmand
- Department of Emergency Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States.
| | - Maryann Mazer-Amirshahi
- Department of Emergency Medicine, MedStar Washington Hospital Center, Washington, DC; Georgetown University School of Medicine, Washington, DC, United States
| | - Sonya Chistov
- Department of Emergency Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States
| | - Youssef Sabha
- Department of Emergency Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States
| | - Damir Vukomanovic
- Department of Emergency Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States
| | - Mohammed Almulhim
- Department of Emergency Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States
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40
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Zafari Z, Dalili M, Zeinali S, Saber S, Fazeli Far AF, Akbari MT. Identification and characterization of a novel recessive KCNQ1 mutation associated with Romano-Ward Long-QT syndrome in two Iranian families. J Electrocardiol 2017; 50:912-918. [PMID: 29033053 DOI: 10.1016/j.jelectrocard.2017.07.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Indexed: 12/20/2022]
Abstract
BACKGROUND One of the foremost causes of sudden cardiac death in the young is an inherent cardiac arrhythmia known as Long-QT syndrome (LQTS). Whereas heterozygous mutations typically lead to the Romano-Ward type of LQTS, We have provided a further evidence for the recessive transmission of a novel KCNQ1 gene mutation in two consanguineous families for the first time in Iran. METHODS Next generation sequencing, DNA Sanger sequencing and haplotype analysis were performed for genotype determination. Twelve different in silico tools were used for predicting the variant pathogenecity along with the family and population study. RESULTS A novel recessive KCNQ1 variant (p.D564G) was revealed in none of the unrelated healthy individuals but four patients in two apparently unrelated families. The variant was classified as a likely pathogenic mutation by combining the resulted criteria for the changed amino acid. CONCLUSIONS Identification of the novel mutation not only supports the genetic testing as a definitive diagnostic tool for detection of at risk family members, but also emphasizes its screening in Iranian LQTS patients as this mutation is very likely a founder mutation in Iran.
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Affiliation(s)
- Zahra Zafari
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mohammad Dalili
- Cardiac Electrophysiology Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Sirus Zeinali
- Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Siamak Saber
- Cardiac Electrophysiology Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Amir Farjam Fazeli Far
- Cardiac Electrophysiology Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Taghi Akbari
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
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41
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Day RO, Snowden L, McLachlan AJ. Life‐threatening drug interactions: what the physician needs to know. Intern Med J 2017; 47:501-512. [DOI: 10.1111/imj.13404] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Revised: 11/11/2016] [Accepted: 11/11/2016] [Indexed: 02/06/2023]
Affiliation(s)
- Richard O. Day
- Department of Clinical Pharmacology and Toxicology St Vincent's Hospital Sydney New South Wales Australia
- School of Medical Sciences, Medicine University of New South Wales Sydney New South Wales Australia
- St Vincent's Clinical School, Medicine University of New South Wales Sydney New South Wales Australia
| | - Leone Snowden
- New South Wales Medicines Information Centre Sydney New South Wales Australia
| | - Andrew J. McLachlan
- Faculty of Pharmacy University of Sydney and Centre for Education and Research on Ageing, Concord Hospital Sydney New South Wales Australia
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42
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Haggerty CM, James CA, Calkins H, Tichnell C, Leader JB, Hartzel DN, Nevius CD, Pendergrass SA, Person TN, Schwartz M, Ritchie MD, Carey DJ, Ledbetter DH, Williams MS, Dewey FE, Lopez A, Penn J, Overton JD, Reid JG, Lebo M, Mason-Suares H, Austin-Tse C, Rehm HL, Delisle BP, Makowski DJ, Mehra VC, Murray MF, Fornwalt BK. Electronic health record phenotype in subjects with genetic variants associated with arrhythmogenic right ventricular cardiomyopathy: a study of 30,716 subjects with exome sequencing. Genet Med 2017; 19:1245-1252. [PMID: 28471438 PMCID: PMC5671380 DOI: 10.1038/gim.2017.40] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 03/03/2017] [Indexed: 01/24/2023] Open
Abstract
Purpose Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited heart disease. Clinical follow-up of incidental findings in ARVC-associated genes is recommended. We aimed to determine the prevalence of disease thus ascertained. Methods 30,716 individuals underwent exome sequencing. Variants in PKP2, DSG2, DSC2, DSP, JUP, TMEM43, or TGFβ3 that were database-listed as pathogenic or likely pathogenic were identified and evidence-reviewed. For subjects with putative loss-of-function (pLOF) variants or variants of uncertain significance (VUS), electronic health records (EHR) were reviewed for ARVC diagnosis, diagnostic criteria, and International Classification of Diseases (ICD-9) codes. Results 18 subjects had pLOF variants; none had an EHR diagnosis of ARVC. Of 14 patients with an electrocardiogram (ECG), one had a minor diagnostic criterion, 13 were normal. 184 subjects had VUSs; none had an ARVC diagnosis. In subjects with VUSs, there was no difference in the proportion with major (4%) or minor (13%) ECG diagnostic criteria compared to variant-negative controls. ICD-9 codes showed no difference in defibrillator utilization, electrophysiologic abnormalities or non-ischemic cardiomyopathies in patients with pLOF or VUSs compared to controls. Conclusion pLOF variants in an unselected cohort were not associated with ARVC phenotypes based on EHR review. The negative predictive value of EHR review remains uncertain.
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Affiliation(s)
- Christopher M Haggerty
- Department of Imaging Science and Innovation, Geisinger Health System, Danville, Pennsylvania, USA
| | - Cynthia A James
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Hugh Calkins
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Crystal Tichnell
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Joseph B Leader
- Biomedical and Translational Informatics Institute, Geisinger Health System, Danville, Pennsylvania, USA
| | - Dustin N Hartzel
- Biomedical and Translational Informatics Institute, Geisinger Health System, Danville, Pennsylvania, USA
| | - Christopher D Nevius
- Department of Imaging Science and Innovation, Geisinger Health System, Danville, Pennsylvania, USA
| | - Sarah A Pendergrass
- Biomedical and Translational Informatics Institute, Geisinger Health System, Danville, Pennsylvania, USA
| | - Thomas N Person
- Biomedical and Translational Informatics Institute, Geisinger Health System, Danville, Pennsylvania, USA
| | - Marci Schwartz
- Genomic Medicine Institute, Geisinger Health System, Danville, Pennsylvania, USA
| | - Marylyn D Ritchie
- Biomedical and Translational Informatics Institute, Geisinger Health System, Danville, Pennsylvania, USA
| | - David J Carey
- Weis Center for Health Research, Geisinger Health System, Danville, Pennsylvania, USA
| | - David H Ledbetter
- Genomic Medicine Institute, Geisinger Health System, Danville, Pennsylvania, USA
| | - Marc S Williams
- Genomic Medicine Institute, Geisinger Health System, Danville, Pennsylvania, USA
| | - Frederick E Dewey
- Regeneron Genetics Center, Regeneron Pharmaceuticals, Tarrytown, New York, USA
| | - Alexander Lopez
- Regeneron Genetics Center, Regeneron Pharmaceuticals, Tarrytown, New York, USA
| | - John Penn
- Regeneron Genetics Center, Regeneron Pharmaceuticals, Tarrytown, New York, USA
| | - John D Overton
- Regeneron Genetics Center, Regeneron Pharmaceuticals, Tarrytown, New York, USA
| | - Jeffrey G Reid
- Regeneron Genetics Center, Regeneron Pharmaceuticals, Tarrytown, New York, USA
| | - Matthew Lebo
- Laboratory for Molecular Medicine, Partners HealthCare Personalized Medicine, Cambridge, Massachusetts, USA.,Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Heather Mason-Suares
- Laboratory for Molecular Medicine, Partners HealthCare Personalized Medicine, Cambridge, Massachusetts, USA.,Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Christina Austin-Tse
- Laboratory for Molecular Medicine, Partners HealthCare Personalized Medicine, Cambridge, Massachusetts, USA
| | - Heidi L Rehm
- Laboratory for Molecular Medicine, Partners HealthCare Personalized Medicine, Cambridge, Massachusetts, USA.,Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Brian P Delisle
- Department of Physiology, University of Kentucky, Lexington, Kentucky, USA
| | - Daniel J Makowski
- Division of Cardiology, Geisinger Health System, Danville, Pennsylvania, USA
| | - Vishal C Mehra
- Division of Cardiology, Geisinger Health System, Danville, Pennsylvania, USA
| | - Michael F Murray
- Genomic Medicine Institute, Geisinger Health System, Danville, Pennsylvania, USA
| | - Brandon K Fornwalt
- Department of Imaging Science and Innovation, Geisinger Health System, Danville, Pennsylvania, USA
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Wang C, Lu Y, Cheng J, Zhang L, Liu W, Peng W, Zhang D, Duan H, Han D, Yuan H. Identification of KCNQ1 compound heterozygous mutations in three Chinese families with Jervell and Lange-Nielsen Syndrome. Acta Otolaryngol 2017; 137:522-528. [PMID: 27917693 DOI: 10.1080/00016489.2016.1260156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
CONCLUSION Besides expanding the spectrum of KCNQ1 mutations causing Jervell and Lange-Nielsen Syndrome (JLNS), the results showed diversity of its phenotypes, and emphasized the importance of molecular genetic analysis in confirming clinical diagnosis and making diagnosis possible before the emergency symptoms for deaf individuals. OBJECTIVES This study aimed to investigate four patients from three Chinese families with congenital hearing loss clinically and genetically. METHOD Genetic analysis of previously reported deafness genes based on massively parallel sequencing was conducted in more than five thousand Chinese hearing loss patients. Detailed clinical features of the patients with compound heterozygous or homozygous mutations of KCNQ1 gene were collected and analyzed. RESULTS Compound mutations of KCNQ1 were found to be the genetic etiology of four patients from three families. Among the six KCNQ1 mutations, c.546C > A was identified as a novel mutation, c.965C > T had been reported in JLNS, while c.683 + 5G > A, c.1484_1485delCT, c.905C > T and c.1831G > A were previously reported in LQT1. In addition to congenital profound hearing loss in all subjects, two sibling subjects showed typical JLNS cardiac phenotype of prolonged QTc and recurrent syncopal episodes. One subject presented not only JLNS, but also iron-deficiency anemia and epilepsy. The other subject did not present any cardiac phenotype.
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Affiliation(s)
- Cuicui Wang
- Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, PR China
- School of Medicine, Nankai University, Tianjin, PR China
| | - Yu Lu
- Medical Genetics Center, Southwest Hospital, Third Military Medical University, Chongqing, PR China
| | - Jing Cheng
- Medical Genetics Center, Southwest Hospital, Third Military Medical University, Chongqing, PR China
| | - Lei Zhang
- Medical Genetics Center, Southwest Hospital, Third Military Medical University, Chongqing, PR China
| | - Wei Liu
- Department of Otolaryngology, Ordos Central Hospital, Ordos, Inner Mongolia Province, PR China
| | - Weihua Peng
- Medical Genetics Center, Southwest Hospital, Third Military Medical University, Chongqing, PR China
| | - Di Zhang
- Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, PR China
| | - Hong Duan
- Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, PR China
| | - Dongyi Han
- Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, PR China
| | - Huijun Yuan
- Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, PR China
- Medical Genetics Center, Southwest Hospital, Third Military Medical University, Chongqing, PR China
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Benjamin EJ, Blaha MJ, Chiuve SE, Cushman M, Das SR, Deo R, de Ferranti SD, Floyd J, Fornage M, Gillespie C, Isasi CR, Jiménez MC, Jordan LC, Judd SE, Lackland D, Lichtman JH, Lisabeth L, Liu S, Longenecker CT, Mackey RH, Matsushita K, Mozaffarian D, Mussolino ME, Nasir K, Neumar RW, Palaniappan L, Pandey DK, Thiagarajan RR, Reeves MJ, Ritchey M, Rodriguez CJ, Roth GA, Rosamond WD, Sasson C, Towfighi A, Tsao CW, Turner MB, Virani SS, Voeks JH, Willey JZ, Wilkins JT, Wu JH, Alger HM, Wong SS, Muntner P. Heart Disease and Stroke Statistics-2017 Update: A Report From the American Heart Association. Circulation 2017; 135:e146-e603. [PMID: 28122885 PMCID: PMC5408160 DOI: 10.1161/cir.0000000000000485] [Citation(s) in RCA: 6046] [Impact Index Per Article: 863.7] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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45
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Fernández-Falgueras A, Sarquella-Brugada G, Brugada J, Brugada R, Campuzano O. Cardiac Channelopathies and Sudden Death: Recent Clinical and Genetic Advances. BIOLOGY 2017; 6:biology6010007. [PMID: 28146053 PMCID: PMC5372000 DOI: 10.3390/biology6010007] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 01/17/2017] [Accepted: 01/20/2017] [Indexed: 12/19/2022]
Abstract
Sudden cardiac death poses a unique challenge to clinicians because it may be the only symptom of an inherited heart condition. Indeed, inherited heart diseases can cause sudden cardiac death in older and younger individuals. Two groups of familial diseases are responsible for sudden cardiac death: cardiomyopathies (mainly hypertrophic cardiomyopathy, dilated cardiomyopathy, and arrhythmogenic cardiomyopathy) and channelopathies (mainly long QT syndrome, Brugada syndrome, short QT syndrome, and catecholaminergic polymorphic ventricular tachycardia). This review focuses on cardiac channelopathies, which are characterized by lethal arrhythmias in the structurally normal heart, incomplete penetrance, and variable expressivity. Arrhythmias in these diseases result from pathogenic variants in genes encoding cardiac ion channels or associated proteins. Due to a lack of gross structural changes in the heart, channelopathies are often considered as potential causes of death in otherwise unexplained forensic autopsies. The asymptomatic nature of channelopathies is cause for concern in family members who may be carrying genetic risk factors, making the identification of these genetic factors of significant clinical importance.
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Affiliation(s)
| | | | - Josep Brugada
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, Barcelona 08950, Spain.
| | - Ramon Brugada
- Cardiovascular Genetics Center, IDIBGI, Girona 17190, Spain.
- Medical Sciences Department, School of Medicine, University of Girona, Girona 17071, Spain.
- Familial Cardiomyopathies Unit, Hospital Josep Trueta, Girona 17007, Spain.
| | - Oscar Campuzano
- Cardiovascular Genetics Center, IDIBGI, Girona 17190, Spain.
- Medical Sciences Department, School of Medicine, University of Girona, Girona 17071, Spain.
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46
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Antoniou CK, Dilaveris P, Manolakou P, Galanakos S, Magkas N, Gatzoulis K, Tousoulis D. QT Prolongation and Malignant Arrhythmia: How Serious a Problem? Eur Cardiol 2017; 12:112-120. [PMID: 30416582 DOI: 10.15420/ecr.2017:16:1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
QT prolongation constitutes one of the most frequently encountered electrical disorders of the myocardium. This is due not only to the presence of several associated congenital syndrome but also, and mainly, due to the QT-prolonging effects of several acquired conditions, such as ischaemia and heart failure, as well as multiple medications from widely different categories. Propensity of repolarization disturbances to arrhythmia appears to be inherent in the function of and electrophysiology of the myocardium. In the present review the issue of QT prolongation will be addressed in terms of pathophysiology, arrhythmogenesis, treatment and risk stratification approaches. Although already discussed in literature, it is hoped that the mechanistic approach of the present review will assist in improved understanding of the underlying changes in electrophysiology, as well as the rationale for current diagnostic and therapeutic approaches.
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Affiliation(s)
| | | | - Panagiota Manolakou
- First Department of Cardiology, Korgialenion-Benakion/Hellenic Red Cross Hospital Athens, Greece
| | - Spyridon Galanakos
- First University Department of Cardiology, Hippokration Hospital Athens, Greece
| | - Nikolaos Magkas
- First University Department of Cardiology, Hippokration Hospital Athens, Greece
| | | | - Dimitrios Tousoulis
- First University Department of Cardiology, Hippokration Hospital Athens, Greece
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47
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Maltese PE, Orlova N, Krasikova E, Emelyanchik E, Cheremisina A, Kuscaeva A, Salmina A, Miotto R, Bonizzato A, Guerri G, Zuntini M, Nicoulina S, Bertelli M. Gene-Targeted Analysis of Clinically Diagnosed Long QT Russian Families. Int Heart J 2016; 58:81-87. [PMID: 28003625 DOI: 10.1536/ihj.16-133] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Long QT syndrome (LQTS) has great genetic heterogeneity: more than 500 mutations have been described in several genes. Despite many advances, a genetic diagnosis still cannot be established in 25-30% of patients. The aim of the present study was to perform genetic evaluation in 9 Russian families with LQTS; here we report the results of 4 positive probands and their relatives (a total of 16 individuals). All subjects underwent clinical examination, 12-lead ECG, and Holter monitoring. Genetic analysis of the 14 genes mainly involved in LQTS was performed using a next-generation sequencing approach. We identified two new mutations (KCNQ1 gene) and 6 known mutations (AKAP9, ANK2, KCNE1 and KCNJ2 genes) in 4 out of 9 probands, some of which have already been described in association with LQTS. Segregation studies suggest a possible causative role for KCNQ1 p.(Leu342Pro), AKAP9 p.(Arg1609Lys), KCNE1 p.(Asp85Asn), and KCNJ2 p.(Arg82Gln) variations. Our study confirmed the high genetic heterogeneity of this disease and highlights the difficulties to reveal clear pathogenic genotypes also in large pedigrees. To the best of our knowledge, this is the first genetic study of LQTS patients from Russian families.
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Tsvetkov D, Kaßmann M, Tano JY, Chen L, Schleifenbaum J, Voelkl J, Lang F, Huang Y, Gollasch M. Do K V 7.1 channels contribute to control of arterial vascular tone? Br J Pharmacol 2016; 174:150-162. [PMID: 28000293 DOI: 10.1111/bph.13665] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 10/11/2016] [Accepted: 10/28/2016] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND AND PURPOSE KV 7.1 voltage-gated potassium channels are expressed in vascular smooth muscle cells (VSMC) of diverse arteries, including mesenteric arteries. Based on pharmacological evidence using R-L3 (KV 7.1 channel opener), HMR1556, chromanol 293B (KV 7.1 channel blockers), stimulation of these channels has been suggested to evoke profound relaxation in various vascular beds of rats. However, the specificity of these drugs in vivo is uncertain. EXPERIMENTAL APPROACH We used Kcnq1-/- mice and pharmacological tools to determine whether KV 7.1 channels play a role in the regulation of arterial tone. KEY RESULTS R-L3 produced similar concentration-dependent relaxations (EC50 ~ 1.4 μM) of arteries from wild-type (Kcnq1+/+ ) and Kcnq1-/- mice, pre-contracted with either phenylephrine or 60 mM KCl. This relaxation was not affected by 10 μM chromanol 293B, 10 μM HMR1556 or 30 μM XE991 (pan-KV 7 channel blocker). The anti-contractile effects of the perivascular adipose tissue (PVAT) were normal in Kcnq1-/- arteries. Chromanol 293B and HMR1556 did not affect the anti-contractile effects of (PVAT). Isolated VSMCs from Kcnq1-/- mice exhibited normal peak KV currents. The KV 7.2-5 channel opener retigabine caused similar relaxations in Kcnq1-/- and wild-type vessels. CONCLUSION AND IMPLICATIONS We conclude that KV 7.1 channels were apparently not involved in the control of arterial tone by α1 -adrenoceptor agonists and PVAT. In addition, R-L3 is an inappropriate pharmacological tool for studying the function of native vascular KV 7.1 channels in mice.
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Affiliation(s)
- Dmitry Tsvetkov
- Experimental and Clinical Research Center (ECRC), A Joint Cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.,Department of Pharmacology and Experimental Therapy, Institute of Experimental and Clinical Pharmacology and Toxicology, Eberhard Karls University Hospitals and Clinics and Interfaculty Center of Pharmacogenomics and Drug Research, University of Tübingen, Tübingen, Germany
| | - Mario Kaßmann
- Experimental and Clinical Research Center (ECRC), A Joint Cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Jean-Yves Tano
- Experimental and Clinical Research Center (ECRC), A Joint Cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Lan Chen
- Experimental and Clinical Research Center (ECRC), A Joint Cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.,Xiamen Zhongshan Hospital, Xiamen University, Xiamen, China
| | - Johanna Schleifenbaum
- Experimental and Clinical Research Center (ECRC), A Joint Cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Jakob Voelkl
- Department of Cardiology, Vascular Medicine and Physiology, University of Tübingen, Tübingen, Germany
| | - Florian Lang
- Department of Cardiology, Vascular Medicine and Physiology, University of Tübingen, Tübingen, Germany
| | - Yu Huang
- School of Biomedical Sciences, 223A, Lo Kwee-Seong Integrated Biomedical Sciences Building, Area 39, Chinese University of Hong Kong, Sha Tin, Hong Kong
| | - Maik Gollasch
- Experimental and Clinical Research Center (ECRC), A Joint Cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.,Medical Clinic for Nephrology and Internal Intensive Care, Campus Virchow, Charité University Medicine, Berlin, Germany
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Neethling A, Mouton J, Loos B, Corfield V, de Villiers C, Kinnear C. Filamin C: a novel component of the KCNE2 interactome during hypoxia. Cardiovasc J Afr 2016; 27:4-11. [PMID: 26956495 PMCID: PMC4816932 DOI: 10.5830/cvja-2015-049] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 05/17/2015] [Indexed: 12/16/2022] Open
Abstract
Aim KCNE2 encodes for the potassium voltage-gated channel, KCNE2. Mutations in KCNE2 have been associated with long-QT syndrome (LQTS). While KCNE2 has been extensively studied, the functions of its C-terminal domain remain inadequately described. Here, we aimed to elucidate the functions of this domain by identifying its protein interactors using yeast two-hybrid analysis. Methods The C-terminal domain of KCNE2 was used as bait to screen a human cardiac cDNA library for putative interacting proteins. Co-localisation and co-immunoprecipitation analyses were used for verification. Results Filamin C (FLNC) was identified as a putative interactor with KCNE2. FLNC and KCNE2 co-localised within the cell, however, a physical interaction was only observed under hypoxic conditions. Conclusion The identification of FLNC as a novel KCNE2 ligand not only enhances current understanding of ion channel function and regulation, but also provides valuable information about possible pathways likely to be involved in LQTS pathogenesis.
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Affiliation(s)
- Annika Neethling
- DST/NRF Centre of Excellence in Biomedical Tuberculosis Research, SA MRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, South Africa
| | - Jomien Mouton
- DST/NRF Centre of Excellence in Biomedical Tuberculosis Research, SA MRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, South Africa
| | - Ben Loos
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa
| | - Valerie Corfield
- DST/NRF Centre of Excellence in Biomedical Tuberculosis Research, SA MRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, South Africa
| | - Carin de Villiers
- DST/NRF Centre of Excellence in Biomedical Tuberculosis Research, SA MRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, South Africa
| | - Craig Kinnear
- DST/NRF Centre of Excellence in Biomedical Tuberculosis Research, SA MRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, South Africa
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Sasaoka S, Matsui T, Hane Y, Abe J, Ueda N, Motooka Y, Hatahira H, Fukuda A, Naganuma M, Hasegawa S, Kinosada Y, Nakamura M. Time-to-Onset Analysis of Drug-Induced Long QT Syndrome Based on a Spontaneous Reporting System for Adverse Drug Events. PLoS One 2016; 11:e0164309. [PMID: 27723808 PMCID: PMC5056697 DOI: 10.1371/journal.pone.0164309] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 09/22/2016] [Indexed: 11/18/2022] Open
Abstract
Long QT syndrome (LQTS) is a disorder of the heart’s electrical activity that infrequently causes severe ventricular arrhythmias such as a type of ventricular tachycardia called torsade de pointes (TdP) and ventricular fibrillation, which can be fatal. There have been no previous reports on the time-to-onset for LQTS based on data from spontaneous reporting systems. The aim of this study was to assess the time-to-onset of LQTS according to drug treatment. We analyzed the association between 113 drugs in 37 therapeutic categories and LQTS including TdP using data obtained from the Japanese Adverse Drug Event Report database. For signal detection, we used the reporting odds ratio (ROR). Furthermore, we analyzed the time-to-onset data and assessed the hazard type using the Weibull shape parameter. The RORs (95% confidence interval) for bepridil, amiodarone, pilsicainide, nilotinib, disopyramide, arsenic trioxide, clarithromycin, cibenzoline, donepezil, famotidine, sulpiride, and nifekalant were 174.4 (148.6–204.6), 17.3 (14.7–20.4), 52.0 (43.4–62.4), 13.9 (11.5–16.7), 69.3 (55.3–86.8), 54.2 (43.2–68.0), 4.7 (3.8–5.8), 19.9 (15.9–25.0), 8.1 (6.5–10.1), 3.2 (2.5–4.1), 7.1 (5.5–9.2), and 254.8 (168.5–385.4), respectively. The medians and quartiles of time-to-onset for aprindine (oral) and bepridil were 20.0 (11.0–35.8) and 18.0 (6.0–43.0) days, respectively. The lower 95% confidence interval of the shape parameter β of bepridil was over 1 and the hazard was considered to increase over time.Our study indicated that the pattern of LQTS onset might differ among drugs. Based on these results, careful long-term observation is recommended, especially for specific drugs such as bepridil and aprindine. This information may be useful for the prevention of sudden death following LQTS and for efficient therapeutic planning.
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Affiliation(s)
- Sayaka Sasaoka
- Laboratory of Drug Informatics, Gifu Pharmaceutical University, Gifu-shi, Gifu, Japan
| | - Toshinobu Matsui
- Laboratory of Drug Informatics, Gifu Pharmaceutical University, Gifu-shi, Gifu, Japan
| | - Yuuki Hane
- Laboratory of Drug Informatics, Gifu Pharmaceutical University, Gifu-shi, Gifu, Japan
| | - Junko Abe
- Laboratory of Drug Informatics, Gifu Pharmaceutical University, Gifu-shi, Gifu, Japan
- Medical database Co., LTD, Shibuya-ku, Tokyo, Japan
| | - Natsumi Ueda
- Laboratory of Drug Informatics, Gifu Pharmaceutical University, Gifu-shi, Gifu, Japan
| | - Yumi Motooka
- Laboratory of Drug Informatics, Gifu Pharmaceutical University, Gifu-shi, Gifu, Japan
| | - Haruna Hatahira
- Laboratory of Drug Informatics, Gifu Pharmaceutical University, Gifu-shi, Gifu, Japan
| | - Akiho Fukuda
- Laboratory of Drug Informatics, Gifu Pharmaceutical University, Gifu-shi, Gifu, Japan
| | - Misa Naganuma
- Laboratory of Drug Informatics, Gifu Pharmaceutical University, Gifu-shi, Gifu, Japan
| | - Shiori Hasegawa
- Laboratory of Drug Informatics, Gifu Pharmaceutical University, Gifu-shi, Gifu, Japan
| | - Yasutomi Kinosada
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, Gifu-shi, Gifu, Japan
| | - Mitsuhiro Nakamura
- Laboratory of Drug Informatics, Gifu Pharmaceutical University, Gifu-shi, Gifu, Japan
- * E-mail:
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