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Harvey A, Caru M, Gonzalez Corcia C, Bertrand É, Gagné V, Dandekar S, Krajinovic M, Gravel H, Laverdière C, Raboisson MJ, Andelfinger G, Jacquemet V, Sinnett D, Curnier D. Uncovering possible silent acquired long QT syndrome using exercise stress testing in long-term pediatric acute lymphoblastic leukemia survivors. Int J Cancer 2024. [PMID: 39244732 DOI: 10.1002/ijc.35168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Revised: 07/18/2024] [Accepted: 07/23/2024] [Indexed: 09/10/2024]
Abstract
An example of chemotherapy-induced cardiotoxicity in cancer survivors is acquired long QT syndrome (aLQTS), which may cause serious yet preventable life-threatening consequences. Our objective was to identify and characterize childhood acute lymphoblastic leukemia (ALL) survivors with possible aLQTS using maximal exercise testing. In this cross-sectional study with exploratory analysis, a total of 250 childhood ALL survivors were evaluated for abnormal QT interval prolongation using the McMaster cycle exercise test. A total of 198 survivors (102 males; 96 females), having reached theirV ̇ O 2 $$ \dot{\mathrm{V}}{\mathrm{O}}_2 $$ peak (mean 32.1 ± 8.4 mL/kg/min; range 15.5-57.8 mL/kg/min), were included in our analyses. Two survivors were excluded for possible congenital LQTS. QT intervals were corrected for heart rate using the Bazett, Fridericia, and Rautaharju formulas at rest (supine, sitting, and standing positions), at the end of each stage of the CPET, and at 1, 3, and 5 minutes into the recovery period. The corrected QT (QTc) of borderline (n = 37) and long QT survivors (n = 20) was significantly longer than normal survivors (n = 141) at rest, exercise, and recovery. Out of 57 survivors presenting an abnormal QTc prolongation, 40 survivors (70%) showed no QT interval anomalies at rest but developed various anomalies during exercise. No significant differences were found between the groups for any of the measured clinical characteristics or cardiac parameters. The standardization of exercise testing in the regular follow-up of oncology patients is necessary for appropriate cardiac prevention and surveillance to enhance the health and quality of life of the ever-increasing number of cancer survivors.
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Affiliation(s)
- Audrey Harvey
- Faculty of Medicine, School of Kinesiology and Physical Activity Sciences, University of Montreal, Montreal, Quebec, Canada
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
| | - Maxime Caru
- Department of Pediatrics, Division of Hematology and Oncology, Pennsylvania State Health Children's Hospital, Hershey, Pennsylvania, USA
| | - Cecilia Gonzalez Corcia
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
- Department of Pediatric Cardiology, Sainte-Justine University Health Center, Montreal, Quebec, Canada
| | - Émilie Bertrand
- Faculty of Medicine, School of Kinesiology and Physical Activity Sciences, University of Montreal, Montreal, Quebec, Canada
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
| | - Vincent Gagné
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
| | - Smita Dandekar
- Department of Pediatrics, Division of Hematology and Oncology, Pennsylvania State Health Children's Hospital, Hershey, Pennsylvania, USA
| | - Maja Krajinovic
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
- Department of Pediatrics, Faculty of Medicine, University of Montreal, Montreal, Quebec, Canada
| | - Hugo Gravel
- Faculty of Medicine, School of Kinesiology and Physical Activity Sciences, University of Montreal, Montreal, Quebec, Canada
| | - Caroline Laverdière
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
- Department of Pediatrics, Faculty of Medicine, University of Montreal, Montreal, Quebec, Canada
| | - Marie-Josée Raboisson
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
- Department of Pediatric Cardiology, Sainte-Justine University Health Center, Montreal, Quebec, Canada
| | - Gregor Andelfinger
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
- Department of Pediatric Cardiology, Sainte-Justine University Health Center, Montreal, Quebec, Canada
| | - Vincent Jacquemet
- Department of Pharmacology and Physiology, Faculty of Medicine, University of Montreal, Montreal, Quebec, Canada
| | - Daniel Sinnett
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
- Department of Pediatrics, Faculty of Medicine, University of Montreal, Montreal, Quebec, Canada
| | - Daniel Curnier
- Faculty of Medicine, School of Kinesiology and Physical Activity Sciences, University of Montreal, Montreal, Quebec, Canada
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
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2
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Harvey A, Curnier D, Dodin P, Jacquemet V, Caru M. The Effects of Cycle Ergometer Versus Treadmill Exercise Stress Testing on QTc Interval Prolongation in Patients With Long QT Syndrome: A Systematic Review and Meta-analysis. Clin J Sport Med 2024; 34:474-502. [PMID: 39012267 DOI: 10.1097/jsm.0000000000001256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 01/16/2024] [Indexed: 07/17/2024]
Abstract
OBJECTIVE The safest and most effective exercise stress tests (EST) modalities for long QT syndrome (LQTS) are currently unknown. The main objective was to explore the effects of EST on the corrected QT interval (QTc) in patients with LQTS, and to compare the effects of different EST modalities (cycle ergometer vs treadmill). DATA SOURCES Systematic searches were performed in September 2022 in accordance with the PRISMA statement through PubMed, Medline, EBM Reviews, Embase, and Web of Science. MAIN RESULTS A total of 1728 patients with LQTS, whether congenital or acquired, without any age restrictions (pediatric age ≤18 years and adult age >19 years), and 2437 control subjects were included in the 49 studies. The QT interval data were available for 15 studies. Our analyses showed that the QT interval prolonged in a similar manner using either a cycle ergometer or a treadmill (standardized mean difference [SMD] = 1.89 [95% CI, 1.07-2.71] vs SMD = 1.46 [95% CI, 0.78-2.14], respectively). Therefore, it seems that either modality may be used to evaluate patients with LQTS. CONCLUSIONS The methodology for the measurement of the QT interval was very heterogeneous between studies, which inevitably influenced the quality of the analyses. Hence, researchers should proceed with caution when exploring and interpreting data in the field of exercise and LQTS.
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Affiliation(s)
- Audrey Harvey
- Laboratory of Pathophysiology of EXercise (LPEX), School of Kinesiology and Physical Activity Sciences, Faculty of Medicine, University of Montreal, Montreal, Canada
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
| | - Daniel Curnier
- Laboratory of Pathophysiology of EXercise (LPEX), School of Kinesiology and Physical Activity Sciences, Faculty of Medicine, University of Montreal, Montreal, Canada
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
| | - Philippe Dodin
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
| | - Vincent Jacquemet
- Department of Pharmacology and Physiology, Faculty of Medicine, University of Montreal, Montreal, Canada ; and
| | - Maxime Caru
- Department of Pediatrics and Department of Public Health Sciences, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
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Takase B, Ikeda T, Shimizu W, Abe H, Aiba T, Chinushi M, Koba S, Kusano K, Niwano S, Takahashi N, Takatsuki S, Tanno K, Watanabe E, Yoshioka K, Amino M, Fujino T, Iwasaki YK, Kohno R, Kinoshita T, Kurita Y, Masaki N, Murata H, Shinohara T, Yada H, Yodogawa K, Kimura T, Kurita T, Nogami A, Sumitomo N. JCS/JHRS 2022 Guideline on Diagnosis and Risk Assessment of Arrhythmia. Circ J 2024; 88:1509-1595. [PMID: 37690816 DOI: 10.1253/circj.cj-22-0827] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Affiliation(s)
| | - Takanori Ikeda
- Department of Cardiovascular Medicine, Toho University Faculty of Medicine
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Nippon Medical School
| | - Haruhiko Abe
- Department of Heart Rhythm Management, University of Occupational and Environmental Health, Japan
| | - Takeshi Aiba
- Department of Clinical Laboratory Medicine and Genetics, National Cerebral and Cardiovascular Center
| | - Masaomi Chinushi
- School of Health Sciences, Niigata University School of Medicine
| | - Shinji Koba
- Division of Cardiology, Department of Medicine, Showa University School of Medicine
| | - Kengo Kusano
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Shinichi Niwano
- Department of Cardiovascular Medicine, Kitasato University School of Medicine
| | - Naohiko Takahashi
- Department of Cardiology and Clinical Examination, Faculty of Medicine, Oita University
| | - Seiji Takatsuki
- Department of Cardiology, Keio University School of Medicine
| | - Kaoru Tanno
- Cardiology Division, Cardiovascular Center, Showa University Koto-Toyosu Hospital
| | - Eiichi Watanabe
- Division of Cardiology, Department of Internal Medicine, Fujita Health University Bantane Hospital
| | | | - Mari Amino
- Department of Cardiology, Tokai University School of Medicine
| | - Tadashi Fujino
- Department of Cardiovascular Medicine, Toho University Faculty of Medicine
| | - Yu-Ki Iwasaki
- Department of Cardiovascular Medicine, Nippon Medical School
| | - Ritsuko Kohno
- Department of Heart Rhythm Management, University of Occupational and Environmental Health, Japan
| | - Toshio Kinoshita
- Department of Cardiovascular Medicine, Toho University Faculty of Medicine
| | - Yasuo Kurita
- Cardiovascular Center, International University of Health and Welfare, Mita Hospital
| | - Nobuyuki Masaki
- Department of Intensive Care Medicine, National Defense Medical College
| | | | - Tetsuji Shinohara
- Department of Cardiology and Clinical Examination, Faculty of Medicine, Oita University
| | - Hirotaka Yada
- Department of Cardiology, International University of Health and Welfare, Mita Hospital
| | - Kenji Yodogawa
- Department of Cardiovascular Medicine, Nippon Medical School
| | - Takeshi Kimura
- Cardiovascular Medicine, Kyoto University Graduate School of Medicine
| | | | - Akihiko Nogami
- Department of Cardiology, Faculty of Medicine, University of Tsukuba
| | - Naokata Sumitomo
- Department of Pediatric Cardiology, Saitama Medical University International Medical Center
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Takase B, Ikeda T, Shimizu W, Abe H, Aiba T, Chinushi M, Koba S, Kusano K, Niwano S, Takahashi N, Takatsuki S, Tanno K, Watanabe E, Yoshioka K, Amino M, Fujino T, Iwasaki Y, Kohno R, Kinoshita T, Kurita Y, Masaki N, Murata H, Shinohara T, Yada H, Yodogawa K, Kimura T, Kurita T, Nogami A, Sumitomo N. JCS/JHRS 2022 Guideline on Diagnosis and Risk Assessment of Arrhythmia. J Arrhythm 2024; 40:655-752. [PMID: 39139890 PMCID: PMC11317726 DOI: 10.1002/joa3.13052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Accepted: 04/22/2024] [Indexed: 08/15/2024] Open
Affiliation(s)
| | - Takanori Ikeda
- Department of Cardiovascular MedicineToho University Faculty of Medicine
| | - Wataru Shimizu
- Department of Cardiovascular MedicineNippon Medical School
| | - Haruhiko Abe
- Department of Heart Rhythm ManagementUniversity of Occupational and Environmental HealthJapan
| | - Takeshi Aiba
- Department of Clinical Laboratory Medicine and GeneticsNational Cerebral and Cardiovascular Center
| | | | - Shinji Koba
- Division of Cardiology, Department of MedicineShowa University School of Medicine
| | - Kengo Kusano
- Department of Cardiovascular MedicineNational Cerebral and Cardiovascular Center
| | - Shinichi Niwano
- Department of Cardiovascular MedicineKitasato University School of Medicine
| | - Naohiko Takahashi
- Department of Cardiology and Clinical Examination, Faculty of MedicineOita University
| | | | - Kaoru Tanno
- Cardiovascular Center, Cardiology DivisionShowa University Koto‐Toyosu Hospital
| | - Eiichi Watanabe
- Division of Cardiology, Department of Internal MedicineFujita Health University Bantane Hospital
| | | | - Mari Amino
- Department of CardiologyTokai University School of Medicine
| | - Tadashi Fujino
- Department of Cardiovascular MedicineToho University Faculty of Medicine
| | - Yu‐ki Iwasaki
- Department of Cardiovascular MedicineNippon Medical School
| | - Ritsuko Kohno
- Department of Heart Rhythm ManagementUniversity of Occupational and Environmental HealthJapan
| | - Toshio Kinoshita
- Department of Cardiovascular MedicineToho University Faculty of Medicine
| | - Yasuo Kurita
- Cardiovascular Center, Mita HospitalInternational University of Health and Welfare
| | - Nobuyuki Masaki
- Department of Intensive Care MedicineNational Defense Medical College
| | | | - Tetsuji Shinohara
- Department of Cardiology and Clinical Examination, Faculty of MedicineOita University
| | - Hirotaka Yada
- Department of CardiologyInternational University of Health and Welfare Mita Hospital
| | - Kenji Yodogawa
- Department of Cardiovascular MedicineNippon Medical School
| | - Takeshi Kimura
- Cardiovascular MedicineKyoto University Graduate School of Medicine
| | | | - Akihiko Nogami
- Department of Cardiology, Faculty of MedicineUniversity of Tsukuba
| | - Naokata Sumitomo
- Department of Pediatric CardiologySaitama Medical University International Medical Center
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5
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Zhu W, Bian X, Lv J. From genes to clinical management: A comprehensive review of long QT syndrome pathogenesis and treatment. Heart Rhythm O2 2024; 5:573-586. [PMID: 39263612 PMCID: PMC11385408 DOI: 10.1016/j.hroo.2024.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2024] Open
Abstract
Background Long QT syndrome (LQTS) is a rare cardiac disorder characterized by prolonged ventricular repolarization and increased risk of ventricular arrhythmias. This review summarizes current knowledge of LQTS pathogenesis and treatment strategies. Objectives The purpose of this study was to provide an in-depth understanding of LQTS genetic and molecular mechanisms, discuss clinical presentation and diagnosis, evaluate treatment options, and highlight future research directions. Methods A systematic search of PubMed, Embase, and Cochrane Library databases was conducted to identify relevant studies published up to April 2024. Results LQTS involves mutations in ion channel-related genes encoding cardiac ion channels, regulatory proteins, and other associated factors, leading to altered cellular electrophysiology. Acquired causes can also contribute. Diagnosis relies on clinical history, electrocardiographic findings, and genetic testing. Treatment strategies include lifestyle modifications, β-blockers, potassium channel openers, device therapy, and surgical interventions. Conclusion Advances in understanding LQTS have improved diagnosis and personalized treatment approaches. Challenges remain in risk stratification and management of certain patient subgroups. Future research should focus on developing novel pharmacological agents, refining device technologies, and conducting large-scale clinical trials. Increased awareness and education are crucial for early detection and appropriate management of LQTS.
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Affiliation(s)
- Wenjing Zhu
- Department of Pulmonary and Critical Care Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
| | - Xueyan Bian
- Department of Pediatrics, Lixia District People's Hospital, Jinan, Shandong, China
| | - Jianli Lv
- Department of Pediatric Cardiology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
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Ifedili I, Maturana M, Kayali S, Levine Y, Kabra R, Jha SK. A case of short QT-interval postventricular arrhythmia arrest from Torsade De Pointes, a new phenotype, or the result of tachycardia-mediated imbalance. J Cardiovasc Electrophysiol 2024; 35:501-504. [PMID: 38174843 DOI: 10.1111/jce.16164] [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: 10/04/2023] [Revised: 12/03/2023] [Accepted: 12/15/2023] [Indexed: 01/05/2024]
Abstract
INTRODUCTION We report the case of an 18-year-old female with recurrent syncope that was discovered to have congenital long QT syndrome (LQTS) and episodes of a transiently short QT interval after spontaneous termination of polymorphic ventricular tachycardia. METHODS & RESULTS A cardiac event monitor revealed a long QT interval and initiation of polymorphic ventricular tachycardia by a premature ventricular complex on the preceding T-wave. After 1 minute of ventricular fibrillation, her arrhythmia spontaneously terminated with evidence of a short QT interval. CONCLUSIONS A transient, potentially artificial, short QT interval following Torsades de Pointes can occur in patients with LQTS.
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Affiliation(s)
- Ikechukwu Ifedili
- Department of Cardiovascular Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Miguel Maturana
- Department of Cardiovascular Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Sharif Kayali
- Department of Cardiovascular Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Yehoshua Levine
- Department of Cardiovascular Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Rajesh Kabra
- Department of Cardiovascular Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, USA
- Kansas City Heart Rhythm Institute, Overland Park, Kansas, USA
| | - Sunil K Jha
- Department of Cardiovascular Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, USA
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7
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Abrahams T, Davies B, Laksman Z, Sy RW, Postema PG, Wilde AAM, Krahn AD, Han HC. Provocation testing in congenital long QT syndrome: A practical guide. Heart Rhythm 2023; 20:1570-1582. [PMID: 37481219 DOI: 10.1016/j.hrthm.2023.07.059] [Citation(s) in RCA: 1] [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: 05/18/2023] [Revised: 07/01/2023] [Accepted: 07/14/2023] [Indexed: 07/24/2023]
Abstract
Congenital long QT syndrome (LQTS) is a hereditary cardiac channelopathy with an estimated prevalence of 1 in 2500. A prolonged resting QT interval corrected for heart rate (QTc interval) remains a key diagnostic component; however, the QTc value may be normal in up to 40% of patients with genotype-positive LQTS and borderline in a further 30%. Provocation of QTc prolongation and T-wave changes may be pivotal to unmasking the diagnosis and useful in predicting genotype. LQTS provocation testing involves assessment of repolarization during and after exercise, in response to changes in heart rate or autonomic tone, with patients with LQTS exhibiting a maladaptive repolarization response. We review the utility and strengths and limitations of 4 forms of provocation testing-stand-up test, exercise stress test, epinephrine challenge, and mental stress test-in diagnosing LQTS and provide some practical guidance for performing provocation testing. Ultimately, exercise testing, when feasible, is the most useful form of provocation testing when considering diagnostic sensitivity and specificity.
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Affiliation(s)
- Timothy Abrahams
- Victorian Heart Institute & Monash Health Heart, Victorian Heart Hospital, Monash University, Melbourne, Victoria, Australia
| | - Brianna Davies
- Center for Cardiovascular Innovation, Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Zachary Laksman
- Center for Cardiovascular Innovation, Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Raymond W Sy
- Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Pieter G Postema
- Department of Cardiology, Amsterdam UMC location University of Amsterdam, Amsterdam, The Netherlands; Heart Failure & Arrhythmias, Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands; European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), Academic Medical Center, Amsterdam, The Netherlands
| | - Arthur A M Wilde
- Department of Cardiology, Amsterdam UMC location University of Amsterdam, Amsterdam, The Netherlands; Heart Failure & Arrhythmias, Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands; European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), Academic Medical Center, Amsterdam, The Netherlands
| | - Andrew D Krahn
- Center for Cardiovascular Innovation, Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Hui-Chen Han
- Victorian Heart Institute & Monash Health Heart, Victorian Heart Hospital, Monash University, Melbourne, Victoria, Australia.
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Yee LA, Han H, Davies B, Pearman CM, Laksman ZWM, Roberts JD, Steinberg C, Tadros R, Cadrin‐Tourigny J, Simpson CS, Gardner M, MacIntyre C, Arbour L, Leather R, Fournier A, Green MS, Kimber S, Angaran P, Sanatani S, Joza J, Khan H, Healey JS, Atallah J, Seifer C, Krahn AD. Sex Differences and Utility of Treadmill Testing in Long‐QT Syndrome. J Am Heart Assoc 2022; 11:e025108. [DOI: 10.1161/jaha.121.025108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background
Diagnosis of congenital long‐QT syndrome (LQTS) is complicated by phenotypic ambiguity, with a frequent normal‐to‐borderline resting QT interval. A 3‐step algorithm based on exercise response of the corrected QT interval (QTc) was previously developed to diagnose patients with LQTS and predict subtype. This study evaluated the 3‐step algorithm in a population that is more representative of the general population with LQTS with milder phenotypes and establishes sex‐specific cutoffs beyond the resting QTc.
Methods and Results
We identified 208 LQTS likely pathogenic or pathogenic
KCNQ1
or
KCNH2
variant carriers in the Canadian NLQTS (National Long‐QT Syndrome) Registry and 215 unaffected controls from the HiRO (Hearts in Rhythm Organization) Registry. Exercise treadmill tests were analyzed across the 5 stages of the Bruce protocol. The predictive value of exercise ECG characteristics was analyzed using receiver operating characteristic curve analysis to identify optimal cutoff values. A total of 78% of male carriers and 74% of female carriers had a resting QTc value in the normal‐to‐borderline range. The 4‐minute recovery QTc demonstrated the best predictive value for carrier status in both sexes, with better LQTS ascertainment in female patients (area under the curve, 0.90 versus 0.82), with greater sensitivity and specificity. The optimal cutoff value for the 4‐minute recovery period was 440 milliseconds for male patients and 450 milliseconds for female patients. The 1‐minute recovery QTc had the best predictive value in female patients for differentiating LQTS1 versus LQTS2 (area under the curve, 0.82), and the peak exercise QTc had a marginally better predictive value in male patients for subtype with (area under the curve, 0.71). The optimal cutoff value for the 1‐minute recovery period was 435 milliseconds for male patients and 455 milliseconds for femal patients.
Conclusions
The 3‐step QT exercise algorithm is a valid tool for the diagnosis of LQTS in a general population with more frequent ambiguity in phenotype. The algorithm is a simple and reliable method for the identification and prediction of the 2 major genotypes of LQTS.
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Affiliation(s)
- Lauren A. Yee
- Center for Cardiovascular Innovation, Heart Rhythm Services, Division of Cardiology, Department of Medicine University of British Columbia Vancouver British Columbia Canada
| | - Hui‐Chen Han
- Center for Cardiovascular Innovation, Heart Rhythm Services, Division of Cardiology, Department of Medicine University of British Columbia Vancouver British Columbia Canada
| | - Brianna Davies
- Center for Cardiovascular Innovation, Heart Rhythm Services, Division of Cardiology, Department of Medicine University of British Columbia Vancouver British Columbia Canada
| | - Charles M. Pearman
- Center for Cardiovascular Innovation, Heart Rhythm Services, Division of Cardiology, Department of Medicine University of British Columbia Vancouver British Columbia Canada
| | - Zachary W. M. Laksman
- Center for Cardiovascular Innovation, Heart Rhythm Services, Division of Cardiology, Department of Medicine University of British Columbia Vancouver British Columbia Canada
| | - Jason D. Roberts
- Population Health Research Institute, McMaster University, and Hamilton Health Sciences Hamilton Ontario Canada
| | - Christian Steinberg
- Institut Universitaire de Cardiologie et Pneumologie de Québec, Laval University Quebec City Quebec Canada
| | - Rafik Tadros
- Cardiovascular Genetics Center, Montreal Heart Institute, Université de Montréal Montreal Quebec Canada
| | - Julia Cadrin‐Tourigny
- Cardiovascular Genetics Center, Montreal Heart Institute, Université de Montréal Montreal Quebec Canada
| | | | - Martin Gardner
- Queen Elizabeth II Health Sciences Center Halifax Nova Scotia Canada
| | - Ciorsti MacIntyre
- Queen Elizabeth II Health Sciences Center Halifax Nova Scotia Canada
| | - Laura Arbour
- Department of Medical Genetics University of British Columbia, and Island Health Victoria British Columbia Canada
| | | | - Anne Fournier
- Centre Hospitalier Universitaire Sainte‐Justine Montréal Quebec Canada
| | | | | | - Paul Angaran
- St. Michael’s Hospital, University of Toronto Toronto Ontario Canada
| | | | - Jacqueline Joza
- McGill University Health Sciences Center Montreal Quebec Canada
| | - Habib Khan
- London Health Sciences Center London Ontario Canada
| | | | | | | | - Andrew D. Krahn
- Center for Cardiovascular Innovation, Heart Rhythm Services, Division of Cardiology, Department of Medicine University of British Columbia Vancouver British Columbia Canada
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Quiroz-Juárez MA, Rosales-Juárez JA, Jiménez-Ramírez O, Vázquez-Medina R, Aragón JL. ECG Patient Simulator Based on Mathematical Models. SENSORS (BASEL, SWITZERLAND) 2022; 22:5714. [PMID: 35957270 PMCID: PMC9370912 DOI: 10.3390/s22155714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/25/2022] [Accepted: 07/27/2022] [Indexed: 06/15/2023]
Abstract
In this work, we propose a versatile, low-cost, and tunable electronic device to generate realistic electrocardiogram (ECG) waveforms, capable of simulating ECG of patients within a wide range of possibilities. A visual analysis of the clinical ECG register provides the cardiologist with vital physiological information to determine the patient's heart condition. Because of its clinical significance, there is a strong interest in algorithms and medical ECG measuring devices that acquire, preserve, and process ECG recordings with high fidelity. Bearing this in mind, the proposed electronic device is based on four different mathematical models describing macroscopic heartbeat dynamics with ordinary differential equations. Firstly, we produce full 12-lead ECG profiles by implementing a model comprising a network of heterogeneous oscillators. Then, we implement a discretized reaction-diffusion model in our electronic device to reproduce ECG waveforms from various rhythm disorders. Finally, in order to show the versatility and capabilities of our system, we include two additional models, a ring of three coupled oscillators and a model based on a quasiperiodic motion, which can reproduce a wide range of pathological conditions. With this, the proposed device can reproduce around thirty-two cardiac rhythms with the possibility of exploring different parameter values to simulate new arrhythmias with the same hardware. Our system, which is a hybrid analog-digital circuit, generates realistic ECG signals through digital-to-analog converters whose amplitudes and waveforms are controlled through an interactive and friendly graphic interface. Our ECG patient simulator arises as a promising platform for assessing the performance of electrocardiograph equipment and ECG signal processing software in clinical trials. Additionally the produced 12-lead profiles can be tested in patient monitoring systems.
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Affiliation(s)
- Mario Alan Quiroz-Juárez
- Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, Queretaro 76230, Mexico;
| | - Juan Alberto Rosales-Juárez
- Instituto Politécnico Nacional, Escuela Superior de Ingeniería Mecánica y Eléctrica, Santa Ana 1000, San Francisco Culhuacán, Mexico City 04430, Mexico; (J.A.R.-J.); (O.J.-R.)
| | - Omar Jiménez-Ramírez
- Instituto Politécnico Nacional, Escuela Superior de Ingeniería Mecánica y Eléctrica, Santa Ana 1000, San Francisco Culhuacán, Mexico City 04430, Mexico; (J.A.R.-J.); (O.J.-R.)
| | - Rubén Vázquez-Medina
- Instituto Politécnico Nacional, Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Cerro Blanco 141, Colinas del Cimatario, Queretaro 76090, Mexico;
| | - José Luis Aragón
- Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, Queretaro 76230, Mexico;
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10
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Yang Y, Lv T, Li S, Liu P, Gao Q, Zhang P. Utility of Provocative Testing in the Diagnosis and Genotyping of Congenital Long QT Syndrome: A Systematic Review and Meta-Analysis. J Am Heart Assoc 2022; 11:e025246. [PMID: 35861842 PMCID: PMC9707831 DOI: 10.1161/jaha.122.025246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Accepted: 04/27/2022] [Indexed: 11/16/2022]
Abstract
Background Diagnosis is particularly challenging in concealed or asymptomatic long QT syndrome (LQTS). Provocative testing, unmasking the characterization of LQTS, is a promising alternative method for the diagnosis of LQTS, but without uniform standards. Methods and Results A comprehensive search was conducted in PubMed, Embase, and the Cochrane Library through October 14, 2021. The fixed effects model was used to assess the effect of the provocative testing on QTc interval. A total of 22 studies with 1137 patients with LQTS were included. At baseline, QTc interval was 40 ms longer in patients with LQTS than in controls (mean difference [MD], 40.54 [95% CI, 37.43-43.65]; P<0.001). Compared with the control group, patients with LQTS had 28 ms longer ΔQTc upon standing (MD, 28.82 [95% CI, 23.05-34.58]; P<0.001), nearly 30 ms longer both at peak exercise (MD, 27.31 [95% CI, 21.51-33.11]; P<0.001) and recovery 4 to 5 minutes (MD, 29.85 [95% CI, 24.36-35.35]; P<0.001). With epinephrine infusion, QTc interval was prolonged both in controls and patients with QTS, most obviously in LQT1 (MD, 68.26 [95% CI, 58.91-77.60]; P<0.001) and LQT2 (MD, 60.17 [95% CI, 50.18-70.16]; P<0.001). Subgroup analysis showed QTc interval response to abrupt stand testing and exercise testing varied between LQT1, LQT2, and LQT3, named Type Ⅰ, Type Ⅱ, and Type Ⅲ. Conclusions QTc trend Type Ⅰ and Type Ⅲ during abrupt stand testing and exercise testing can be used to propose a prospective evaluation of LQT1 and LQT3, respectively. Type Ⅱ QTc trend combined epinephrine infusion testing could distinguish LQT2 from control. A preliminary diagnostic workflow was proposed but deserves further evaluation.
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Affiliation(s)
- Ying Yang
- School of Clinical MedicineTsinghua UniversityBeijingChina
| | - Ting‐ting Lv
- Department of CardiologySchool of Clinical MedicineBeijing Tsinghua Changgung HospitalTsinghua UniversityBeijingChina
| | - Si‐yuan Li
- Department of CardiologySchool of Clinical MedicineBeijing Tsinghua Changgung HospitalTsinghua UniversityBeijingChina
| | - Peng Liu
- School of Clinical MedicineTsinghua UniversityBeijingChina
| | - Qing‐gele Gao
- School of Clinical MedicineTsinghua UniversityBeijingChina
| | - Ping Zhang
- School of Clinical MedicineTsinghua UniversityBeijingChina
- Department of CardiologySchool of Clinical MedicineBeijing Tsinghua Changgung HospitalTsinghua UniversityBeijingChina
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11
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Rieder M, Kreifels P, Stuplich J, Ziupa D, Servatius H, Nicolai L, Castiglione A, Zweier C, Asatryan B, Odening KE. Genotype-Specific ECG-Based Risk Stratification Approaches in Patients With Long-QT Syndrome. Front Cardiovasc Med 2022; 9:916036. [PMID: 35911527 PMCID: PMC9329832 DOI: 10.3389/fcvm.2022.916036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 06/13/2022] [Indexed: 11/13/2022] Open
Abstract
Background Congenital long-QT syndrome (LQTS) is a major cause of sudden cardiac death (SCD) in young individuals, calling for sophisticated risk assessment. Risk stratification, however, is challenging as the individual arrhythmic risk varies pronouncedly, even in individuals carrying the same variant. Materials and Methods In this study, we aimed to assess the association of different electrical parameters with the genotype and the symptoms in patients with LQTS. In addition to the heart-rate corrected QT interval (QTc), markers for regional electrical heterogeneity, such as QT dispersion (QTmax-QTmin in all ECG leads) and delta Tpeak/end (Tpeak/end V5 – Tpeak/end V2), were assessed in the 12-lead ECG at rest and during exercise testing. Results QTc at rest was significantly longer in symptomatic than asymptomatic patients with LQT2 (493.4 ms ± 46.5 ms vs. 419.5 ms ± 28.6 ms, p = 0.004), but surprisingly not associated with symptoms in LQT1. In contrast, post-exercise QTc (minute 4 of recovery) was significantly longer in symptomatic than asymptomatic patients with LQT1 (486.5 ms ± 7.0 ms vs. 463.3 ms ± 16.3 ms, p = 0.04), while no such difference was observed in patients with LQT2. Enhanced delta Tpeak/end and QT dispersion were only associated with symptoms in LQT1 (delta Tpeak/end 19.0 ms ± 18.1 ms vs. −4.0 ms ± 4.4 ms, p = 0.02; QT-dispersion: 54.3 ms ± 10.2 ms vs. 31.4 ms ± 10.4 ms, p = 0.01), but not in LQT2. Delta Tpeak/end was particularly discriminative after exercise, where all symptomatic patients with LQT1 had positive and all asymptomatic LQT1 patients had negative values (11.8 ± 7.9 ms vs. −7.5 ± 1.7 ms, p = 0.003). Conclusion Different electrical parameters can distinguish between symptomatic and asymptomatic patients in different genetic forms of LQTS. While the classical “QTc at rest” was only associated with symptoms in LQT2, post-exercise QTc helped distinguish between symptomatic and asymptomatic patients with LQT1. Enhanced regional electrical heterogeneity was only associated with symptoms in LQT1, but not in LQT2. Our findings indicate that genotype-specific risk stratification approaches based on electrical parameters could help to optimize risk assessment in LQTS.
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Affiliation(s)
- Marina Rieder
- Translational Cardiology, Department of Cardiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Paul Kreifels
- Department of Cardiology and Angiology I, Faculty of Medicine, University Heart Center Freiburg-Bad Krozingen, University of Freiburg, Freiburg, Germany
| | - Judith Stuplich
- Department of Cardiology and Angiology I, Faculty of Medicine, University Heart Center Freiburg-Bad Krozingen, University of Freiburg, Freiburg, Germany
| | - David Ziupa
- Department of Cardiology and Angiology I, Faculty of Medicine, University Heart Center Freiburg-Bad Krozingen, University of Freiburg, Freiburg, Germany
| | - Helge Servatius
- Translational Cardiology, Department of Cardiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Luisa Nicolai
- Translational Cardiology, Department of Cardiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Alessandro Castiglione
- Translational Cardiology, Department of Cardiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Christiane Zweier
- Department of Human Genetics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Babken Asatryan
- Translational Cardiology, Department of Cardiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Katja E Odening
- Translational Cardiology, Department of Cardiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
- Department of Physiology, University of Bern, Bern, Switzerland
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12
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Krahn AD, Laksman Z, Sy RW, Postema PG, Ackerman MJ, Wilde AAM, Han HC. Congenital Long QT Syndrome. JACC Clin Electrophysiol 2022; 8:687-706. [PMID: 35589186 DOI: 10.1016/j.jacep.2022.02.017] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 02/16/2022] [Accepted: 02/16/2022] [Indexed: 12/14/2022]
Abstract
Congenital long QT syndrome (LQTS) encompasses a group of heritable conditions that are associated with cardiac repolarization dysfunction. Since its initial description in 1957, our understanding of LQTS has increased dramatically. The prevalence of LQTS is estimated to be ∼1:2,000, with a slight female predominance. The diagnosis of LQTS is based on clinical, electrocardiogram, and genetic factors. Risk stratification of patients with LQTS aims to identify those who are at increased risk of cardiac arrest or sudden cardiac death. Factors including age, sex, QTc interval, and genetic background all contribute to current risk stratification paradigms. The management of LQTS involves conservative measures such as the avoidance of QT-prolonging drugs, pharmacologic measures with nonselective β-blockers, and interventional approaches such as device therapy or left cardiac sympathetic denervation. In general, most forms of exercise are considered safe in adequately treated patients, and implantable cardioverter-defibrillator therapy is reserved for those at the highest risk. This review summarizes our current understanding of LQTS and provides clinicians with a practical approach to diagnosis and management.
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Affiliation(s)
- Andrew D Krahn
- Center for Cardiovascular Innovation, Heart Rhythm Services, Division of Cardiology, University of British Columbia, Vancouver, BC, Canada.
| | - Zachary Laksman
- Center for Cardiovascular Innovation, Heart Rhythm Services, Division of Cardiology, University of British Columbia, Vancouver, BC, Canada
| | - Raymond W Sy
- Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Pieter G Postema
- Department of Clinical and Experimental Cardiology, Heart Center, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - Michael J Ackerman
- Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Windland Smith Rice Genetic Heart Rhythm Clinic, Mayo Clinic, Rochester, Minnesota, USA; Department of Pediatric and Adolescent Medicine, Division of Pediatric Cardiology, Mayo Clinic, Rochester, Minnesota, USA; Departments of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Arthur A M Wilde
- Department of Clinical and Experimental Cardiology, Heart Center, Amsterdam University Medical Centers, Amsterdam, the Netherlands; European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart (ERN GUARD-Heart), Academic University Medical Center, Amsterdam, the Netherlands
| | - Hui-Chen Han
- Center for Cardiovascular Innovation, Heart Rhythm Services, Division of Cardiology, University of British Columbia, Vancouver, BC, Canada; Victorian Heart Institute, Monash University, Clayton, VIC, Australia
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13
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Harvey A, Curnier D, Dodin P, Abadir S, Jacquemet V, Caru M. OUP accepted manuscript. Eur J Prev Cardiol 2022; 29:1633-1677. [PMID: 35537006 DOI: 10.1093/eurjpc/zwac081] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 04/15/2022] [Accepted: 04/18/2022] [Indexed: 11/13/2022]
Abstract
Current exercise recommendations make it difficult for long QT syndrome (LQTS) patients to adopt a physically active and/or athletic lifestyle. The purpose of this review is to summarize the current evidence, identify knowledge gaps, and discuss research perspectives in the field of exercise and LQTS. The first aim is to document the influence of exercise training, exercise stress, and postural change interventions on ventricular repolarization in LQTS patients, while the second aim is to describe electrophysiological measurements used to study the above. Studies examining the effects of exercise on congenital or acquired LQTS in human subjects of all ages were included. Systematic searches were performed on 1 October 2021, through PubMed (NLM), Ovid Medline, Ovid All EBM Reviews, Ovid Embase, and ISI Web of Science, and limited to articles written in English or French. A total of 1986 LQTS patients and 2560 controls were included in the 49 studies. Studies were mainly case-control studies (n = 41) and examined exercise stress and/or postural change interventions (n = 48). One study used a 3-month exercise training program. Results suggest that LQTS patients have subtype-specific repolarization responses to sympathetic stress. Measurement methods and quality were found to be very heterogeneous, which makes inter-study comparisons difficult. In the absence of randomized controlled trials, the current recommendations may have long-term risks for LQTS patients who are discouraged from performing physical activity, rendering its associated health benefits out of range. Future research should focus on discovering the most appropriate levels of exercise training that promote ventricular repolarization normalization in LQTS.
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Affiliation(s)
- Audrey Harvey
- Laboratory of Pathophysiology of EXercise (LPEX), School of Kinesiology and Physical Activity Sciences, Faculty of Medicine, University of Montreal, Montreal, Canada
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
| | - Daniel Curnier
- Laboratory of Pathophysiology of EXercise (LPEX), School of Kinesiology and Physical Activity Sciences, Faculty of Medicine, University of Montreal, Montreal, Canada
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
| | - Philippe Dodin
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
| | - Sylvia Abadir
- Department of Pediatric Cardiology, Sainte-Justine University Health Center, Montreal, Canada
| | - Vincent Jacquemet
- Department of Pharmacology and Physiology, Faculty of Medicine, University of Montreal, Montreal, Canada
| | - Maxime Caru
- Sainte-Justine University Health Center, Research Center, Montreal, Canada
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA, USA
- Department of Public Health Sciences, Pennsylvania State University College of Medicine, Hershey, PA, USA
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14
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Steinberg C, Pilote S, Philippon F, Laksman ZW, Champagne J, Simard C, Krahn AD, Drolet B. SCN5A-C683R exhibits combined gain-of-function and loss-of-function properties related to adrenaline-triggered ventricular arrhythmia. Exp Physiol 2021; 106:683-699. [PMID: 33480457 DOI: 10.1113/ep089088] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 01/11/2021] [Indexed: 12/14/2022]
Abstract
NEW FINDINGS What is the role of SCN5A-C683R? SCN5A-C683R is a novel variant associated with an uncommon phenotype of adrenaline-triggered ventricular arrhythmia in the absence of a distinct ECG phenotype. What is the main finding and its importance? Functional studies demonstrated that NaV 1.5/C683R results in a mixed electrophysiological phenotype with gain-of-function (GOF) and loss-of-function (LOF) properties compared with NaV 1.5/wild type. Gain-of-function properties are characterized by a significant increase of the maximal current density and a hyperpolarizing shift of the steady-state activation. The LOF effect of NaV 1.5/C683R is characterized by increased closed-state inactivation. Electrophysiological properties and clinical manifestation of SCN5A-C683R are different from long-QT-3 or Brugada syndrome and might represent a distinct inherited arrhythmia syndrome. ABSTRACT Mutations of SCN5Ahave been identified as the genetic substrate of various inherited arrhythmia syndromes, including long-QT-3 and Brugada syndrome. We recently identified a novel SCN5A variant (C683R) in two genetically unrelated families. The index patients of both families experienced adrenaline-triggered ventricular arrhythmia with cardiac arrest but did not show a specific ECG phenotype, raising the hypothesis that SCN5A-C683R might be a susceptibility variant and the genetic substrate of distinct inherited arrhythmia. We conducted functional cellular studies to characterize the electrophysiological properties of NaV 1.5/C683R in order to explore the potential pathogenicity of this novel variant. The C683R variant was engineered by site-directed mutagenesis. NaV 1.5/wild type (WT) and NaV 1.5/C683R were expressed in tsA201 cells. Electrophysiological characterization of C683R was performed using the whole-cell patch-clamp technique. Adrenergic stimulation was mimicked by exposure to the protein kinase A activator 8-CPT-cAMP. The impact of β-blockers was tested by exposing NaV 1.5/WT and NaV 1.5/C683R currents to propranolol and nadolol. C683R resulted in a co-association of gain-of-function and loss-of-function properties of NaV 1.5. Gain-of-function properties were characterized by a significant increase of the maximal NaV 1.5 current density compared with NaV 1.5/WT (861 ± 309 vs. 627 ± 489 pA/pF; P < 0.05, n ≥ 9) that was potentiated in NaV 1.5/C683R with 8-CPT-cAMP stimulation (869 ± 287 vs. 607 ± 320 pA/pF; P < 0.05, n ≥ 12). C683R also resulted in a significant hyperpolarizing shift in the voltage of steady-state activation (-65.4 ± 3.0 vs. -57.2 ± 4.8 mV; P < 0.001), resulting in an increased window current compared with WT. The loss-of-function effect of NaV 1.5/C683R was characterized by significantly increased closed-state inactivation compared with NaV 1.5/WT (P < 0.05). C683R is a novel SCN5A variant resulting in a co-association of gain-of-function and loss-of-function properties of the cardiac sodium channel NaV 1.5. The phenotype is characterized by adrenaline-triggered ventricular arrhythmias. Electrophysiological properties and clinical manifestations are different from long-QT-3 or Brugada syndrome and might represent a distinct inherited arrhythmia syndrome.
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Affiliation(s)
- Christian Steinberg
- Division of Cardiology, Electrophysiology Service, Institut universitaire de cardiologie et de pneumologie de Québec, IUCPQ-UL), Laval University, Québec, QC, Canada.,IUCPQ-UL Research Center, Laval University, Québec, QC, Canada
| | - Sylvie Pilote
- IUCPQ-UL Research Center, Laval University, Québec, QC, Canada.,Faculty of Pharmacy, Laval University, Québec, QC, Canada
| | - François Philippon
- Division of Cardiology, Electrophysiology Service, Institut universitaire de cardiologie et de pneumologie de Québec, IUCPQ-UL), Laval University, Québec, QC, Canada.,IUCPQ-UL Research Center, Laval University, Québec, QC, Canada
| | - Zachary W Laksman
- Heart Rhythm Services, St. Paul's Hospital, University of British Columbia, Vancouver, BC, Canada
| | - Jean Champagne
- Division of Cardiology, Electrophysiology Service, Institut universitaire de cardiologie et de pneumologie de Québec, IUCPQ-UL), Laval University, Québec, QC, Canada.,IUCPQ-UL Research Center, Laval University, Québec, QC, Canada
| | - Chantale Simard
- IUCPQ-UL Research Center, Laval University, Québec, QC, Canada.,Faculty of Pharmacy, Laval University, Québec, QC, Canada
| | - Andrew D Krahn
- Heart Rhythm Services, St. Paul's Hospital, University of British Columbia, Vancouver, BC, Canada
| | - Benoît Drolet
- IUCPQ-UL Research Center, Laval University, Québec, QC, Canada.,Faculty of Pharmacy, Laval University, Québec, QC, Canada
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15
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Marwick TH. Echocardiography in Long QT Syndrome: The Mechanical Face of an Electrical Disease. J Am Coll Cardiol 2020; 76:2844-2846. [PMID: 33303073 DOI: 10.1016/j.jacc.2020.10.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 10/27/2020] [Indexed: 10/22/2022]
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16
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Almahameed ST, Kaufman ES. Idiopathic Ventricular Fibrillation: Diagnosis, Ablation of Triggers, Gaps in Knowledge, and Future Directions. J Innov Card Rhythm Manag 2020; 11:4135-4146. [PMID: 32596029 PMCID: PMC7313628 DOI: 10.19102/icrm.2020.110604] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Accepted: 03/12/2020] [Indexed: 01/14/2023] Open
Abstract
Idiopathic ventricular fibrillation (IVF) is a diagnosis of exclusion made when no underlying cause is identified in a cardiac arrest survivor. Although the frequency of this diagnosis has declined over time due to advances in diagnostic techniques, it remains a substantial cause of sudden cardiac arrest. Further, IVF tends to recur. This article reviews the criteria for diagnosis, patient characteristics, the two primary arrhythmic phenotypes—short-coupled variant of torsades de pointes and recurrent paroxysmal IVF—and the electrophysiologic features, treatment, and ablation of premature ventricular complexes that can trigger IVF.
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Affiliation(s)
- Soufian T Almahameed
- Heart and Vascular Center, MetroHealth Campus of Case Western Reserve University, Cleveland, OH, USA
| | - Elizabeth S Kaufman
- Heart and Vascular Center, MetroHealth Campus of Case Western Reserve University, Cleveland, OH, USA
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17
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Janzen M, Cheung CC, Steinberg C, Lam PY, Krahn AD. Changes on the electrocardiogram in anorexia nervosa: A case control study. J Electrocardiol 2019; 56:64-69. [PMID: 31319227 DOI: 10.1016/j.jelectrocard.2019.07.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 07/02/2019] [Accepted: 07/07/2019] [Indexed: 11/30/2022]
Abstract
PURPOSE Anorexia nervosa is a complex psychiatric condition with increased mortality. The electrocardiogram (ECG) may show repolarization changes which may associate with an increased risk of sudden death. Up to 80% of patients may be prescribed psychopharmacotherapies which alter the ECG, potentially compounding arrhythmic risk. This study aimed to describe and improve understanding of ECG changes in eating disorders and assess the effect of psychopharmacotherapies. METHODS Adolescent patients diagnosed with anorexia nervosa were reviewed. ECGs were reviewed by blinded expert reviewers, and repolarization parameters were compared to healthy controls. Patients on and off psychopharmacotherapies were compared. RESULTS Thirty-eight anorexia nervosa patients off psychopharmacotherapies were age matched to 53 healthy controls. Heart rate was lower in anorexia nervosa patients (56 vs. 74 bpm, p < 0.001). The absolute QT interval was longer in patients compared to controls (408 vs. 383 ms, p < 0.001), but the QTc by Hodges' formula was similar between groups (401 vs. 408 ms, p = 0.16). The prevalence of T-wave flattening and inversion was also similar between groups (13% vs. 4%, p = 0.12) and T-peak to T-end interval (Tpe) was shorter in patients compared to controls (p < 0.01). ECG parameters were similar between patients on and off psychopharmacotherapies aside from off-drug patients showing lower HR (56 vs. 65, p = 0.04). CONCLUSIONS Autonomic and repolarization changes are evident on the ECG of anorexia nervosa patients, though the QTc interval was in fact similar between groups. Changes in T-wave morphology and duration may be promising metrics of repolarization effects of anorexia nervosa.
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Affiliation(s)
- Mikyla Janzen
- Heart Rhythm Services, Division of Cardiology, Department of Medicine, University of British Columbia, 220-1033 Davie St, Vancouver, British Columbia V6E 1M5, Canada.
| | - Christopher C Cheung
- Heart Rhythm Services, Division of Cardiology, Department of Medicine, University of British Columbia, 220-1033 Davie St, Vancouver, British Columbia V6E 1M5, Canada.
| | - Christian Steinberg
- Heart Rhythm Services, Division of Cardiology, Department of Medicine, University of British Columbia, 220-1033 Davie St, Vancouver, British Columbia V6E 1M5, Canada.
| | - Pei-Yoong Lam
- Department of Pediatrics, University of British Columbia, 4480 Oak St, Vancouver, British Columbia V6H 3N1, Canada.
| | - Andrew D Krahn
- Heart Rhythm Services, Division of Cardiology, Department of Medicine, University of British Columbia, 220-1033 Davie St, Vancouver, British Columbia V6E 1M5, Canada.
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18
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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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19
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Skinner JR, Winbo A, Abrams D, Vohra J, Wilde AA. Channelopathies That Lead to Sudden Cardiac Death: Clinical and Genetic Aspects. Heart Lung Circ 2019; 28:22-30. [DOI: 10.1016/j.hlc.2018.09.007] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 09/20/2018] [Accepted: 09/23/2018] [Indexed: 12/19/2022]
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20
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2017 AHA/ACC/HRS guideline for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death. Heart Rhythm 2018; 15:e73-e189. [DOI: 10.1016/j.hrthm.2017.10.036] [Citation(s) in RCA: 177] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Indexed: 02/07/2023]
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21
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Al-Khatib SM, Stevenson WG, Ackerman MJ, Bryant WJ, Callans DJ, Curtis AB, Deal BJ, Dickfeld T, Field ME, Fonarow GC, Gillis AM, Granger CB, Hammill SC, Hlatky MA, Joglar JA, Kay GN, Matlock DD, Myerburg RJ, Page RL. 2017 AHA/ACC/HRS Guideline for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. Circulation 2018; 138:e272-e391. [PMID: 29084731 DOI: 10.1161/cir.0000000000000549] [Citation(s) in RCA: 249] [Impact Index Per Article: 41.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
| | - William G Stevenson
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Michael J Ackerman
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - William J Bryant
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - David J Callans
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Anne B Curtis
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Barbara J Deal
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Timm Dickfeld
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Michael E Field
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Gregg C Fonarow
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Anne M Gillis
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Christopher B Granger
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Stephen C Hammill
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Mark A Hlatky
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - José A Joglar
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - G Neal Kay
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Daniel D Matlock
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Robert J Myerburg
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Richard L Page
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
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Al-Khatib SM, Stevenson WG, Ackerman MJ, Bryant WJ, Callans DJ, Curtis AB, Deal BJ, Dickfeld T, Field ME, Fonarow GC, Gillis AM, Granger CB, Hammill SC, Hlatky MA, Joglar JA, Kay GN, Matlock DD, Myerburg RJ, Page RL. 2017 AHA/ACC/HRS Guideline for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. Circulation 2018; 138:e210-e271. [PMID: 29084733 DOI: 10.1161/cir.0000000000000548] [Citation(s) in RCA: 153] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
| | - William G Stevenson
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Michael J Ackerman
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - William J Bryant
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - David J Callans
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Anne B Curtis
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Barbara J Deal
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Timm Dickfeld
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Michael E Field
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Gregg C Fonarow
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Anne M Gillis
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Christopher B Granger
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Stephen C Hammill
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Mark A Hlatky
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - José A Joglar
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - G Neal Kay
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Daniel D Matlock
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Robert J Myerburg
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
| | - Richard L Page
- Writing committee members are required to recuse themselves from voting on sections to which their specific relationships with industry may apply; see Appendix 1 for detailed information. Section numbers pertain to those in the full-text guideline. †ACC/AHA Representative. ‡HRS Representative. §ACC/AHA Task Force on Performance Measures Liaison/HFSA Representative. ‖ACC/AHA Task Force on Clinical Practice Guidelines Liaison
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Al-Khatib SM, Stevenson WG, Ackerman MJ, Bryant WJ, Callans DJ, Curtis AB, Deal BJ, Dickfeld T, Field ME, Fonarow GC, Gillis AM, Granger CB, Hammill SC, Hlatky MA, Joglar JA, Kay GN, Matlock DD, Myerburg RJ, Page RL. 2017 AHA/ACC/HRS Guideline for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. J Am Coll Cardiol 2018; 72:e91-e220. [PMID: 29097296 DOI: 10.1016/j.jacc.2017.10.054] [Citation(s) in RCA: 707] [Impact Index Per Article: 117.8] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Schnell F, Behar N, Carré F. Long-QT Syndrome and Competitive Sports. Arrhythm Electrophysiol Rev 2018; 7:187-192. [PMID: 30416732 PMCID: PMC6141947 DOI: 10.15420/aer.2018.39.3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Accepted: 07/17/2018] [Indexed: 01/02/2023] Open
Abstract
Long QT syndrome (LQTS) is an inherited channelopathy which exposes athletes to a risk of sudden cardiac death. Diagnosis is more difficult in this population because: the QT interval is prolonged by training; and the extreme bradycardia frequently observed in athletes makes the QT correction formula less accurate. Based on limited clinical data which tend to demonstrate that exercise, especially swimming, is a trigger for cardiac events, participation in any competitive sports practice is not supported by 2005 European guidelines. However, based on recent retrospective studies and adopting a different medical approach, involving the patient-athlete in shared decision making, the 2015 US guidelines are less restrictive, especially in asymptomatic genotype-positive/phenotype-negative athletes. These guidelines also consider giving medical clearance to competitive sport participation in asymptomatic athletes with appropriate medical therapy.
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Affiliation(s)
- Frédéric Schnell
- University of Rennes, Department of Sports MedicineUniversity Hospital of Rennes, Inserm, LTSI-UMR 1099 Rennes, France
| | - Nathalie Behar
- University of Rennes, Department of Cardiology UniversityHospital of Rennes, Inserm, LTSI-UMR 1099 Rennes, France
| | - François Carré
- University of Rennes, Department of Sports MedicineUniversity Hospital of Rennes, Inserm, LTSI-UMR 1099 Rennes, France
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Caro-Codón J, Iniesta Manjavacas ÁM, Moreno Yangüela M. Response to ECG, June 2018. REVISTA ESPANOLA DE CARDIOLOGIA (ENGLISH ED.) 2018; 71:579. [PMID: 29958588 DOI: 10.1016/j.rec.2017.12.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 12/18/2017] [Indexed: 06/08/2023]
Affiliation(s)
- Juan Caro-Codón
- Servicio de Cardiología, Hospital Universitario La Paz, Madrid, Spain.
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Caro-Codón J, Iniesta Manjavacas ÁM, Moreno Yangüela M. Respuesta al ECG de junio de 2018. Rev Esp Cardiol (Engl Ed) 2018. [DOI: 10.1016/j.recesp.2017.12.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Srinivasan NT, Schilling RJ. Sudden Cardiac Death and Arrhythmias. Arrhythm Electrophysiol Rev 2018; 7:111-117. [PMID: 29967683 PMCID: PMC6020177 DOI: 10.15420/aer.2018:15:2] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 04/30/2018] [Indexed: 01/01/2023] Open
Abstract
Sudden cardiac death (SCD) and arrhythmia represent a major worldwide public health problem, accounting for 15-20 % of all deaths. Early resuscitation and defibrillation remains the key to survival, yet its implementation and the access to public defibrillators remains poor, resulting in overall poor survival to patients discharged from hospital. Novel approaches employing smart technology may provide the solution to this dilemma. Though the majority of cases are attributable to coronary artery disease, a thorough search for an underlying cause in cases where the diagnosis is unclear is necessary. This enables better management of arrhythmia recurrence and screening of family members. The majority of cases of SCD occur in patients who do not have traditional risk factors for arrhythmia. New and improved large scale screening tools are required to better predict risk in the wider population who represent the majority of cases of SCD.
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Gravel H, Jacquemet V, Dahdah N, Curnier D. Clinical applications of QT/RR hysteresis assessment: A systematic review. Ann Noninvasive Electrocardiol 2017; 23. [PMID: 29083088 DOI: 10.1111/anec.12514] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 09/17/2017] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND QT/RR hysteresis (QT-hys) is an index of the time accommodation of ventricular repolarization to heart rate changes. This report comprehensively reviews studies addressing QT-hys as a biomarker of medical conditions. METHODS This is a secondary analysis of data from a recent systematic review pertaining to methods of assessment of QT-hys. Articles included in the former review were filtered in order to select original articles investigating the association of QT-hys with medical conditions in humans. RESULTS Nineteen articles fulfilled our inclusion criteria. Given the heterogeneity of the methods and investigated conditions, no pooled analysis of data could be implemented. QT-hys was mostly studied as a risk marker of severe arrhythmias, as a predictor of the long QT syndrome (LQTS) phenotypes and genotypes and as a marker of exercise-induced ischemia. An increased QT-hys appears to be implicated in arrhythmogenesis, although the evidence in this regard relies on few human studies. An augmented QT-hys was reported in the LQTS, predominantly in the LQT2 genotype, but conflicting results were obtained between studies using different methods of assessment. In addition, QT-hys appears to be a useful marker of stress-induced myocardial ischemia in patients suspected of coronary artery disease. CONCLUSIONS QT-hys evaluation has potential clinical utility in at least some clinical conditions. Further studies of the clinical validity of QT-hys assessment are warranted, particularly condition specific studies based on QT-hys evaluation methods that provide separate estimates of QT-hys and QT/RR dependency.
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Affiliation(s)
- Hugo Gravel
- Department of Kinesiology, University of Montreal, Montreal, QC, Canada
| | - Vincent Jacquemet
- Department of Pharmacology and Physiology, Faculty of Medicine, University of Montreal, Montreal, QC, Canada
| | - Nagib Dahdah
- Division of Pediatric Cardiology and CHU Ste-Justine Research Center, CHU Ste-Justine, Montreal, QC, Canada
| | - Daniel Curnier
- Department of Kinesiology, University of Montreal, Montreal, QC, Canada
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Al-Khatib SM, Stevenson WG, Ackerman MJ, Bryant WJ, Callans DJ, Curtis AB, Deal BJ, Dickfeld T, Field ME, Fonarow GC, Gillis AM, Granger CB, Hammill SC, Hlatky MA, Joglar JA, Kay GN, Matlock DD, Myerburg RJ, Page RL. 2017 AHA/ACC/HRS Guideline for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. J Am Coll Cardiol 2017; 72:1677-1749. [PMID: 29097294 DOI: 10.1016/j.jacc.2017.10.053] [Citation(s) in RCA: 249] [Impact Index Per Article: 35.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Al-Khatib SM, Stevenson WG, Ackerman MJ, Bryant WJ, Callans DJ, Curtis AB, Deal BJ, Dickfeld T, Field ME, Fonarow GC, Gillis AM, Granger CB, Hammill SC, Hlatky MA, Joglar JA, Kay GN, Matlock DD, Myerburg RJ, Page RL. 2017 AHA/ACC/HRS guideline for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death: Executive summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. Heart Rhythm 2017; 15:e190-e252. [PMID: 29097320 DOI: 10.1016/j.hrthm.2017.10.035] [Citation(s) in RCA: 391] [Impact Index Per Article: 55.9] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Indexed: 12/23/2022]
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Dionne A, Fournier A, Dahdah N, Abrams D, Khairy P, Abadir S. Dynamic QT Interval Changes from Supine to Standing in Healthy Children. Can J Cardiol 2017; 34:66-72. [PMID: 29275885 DOI: 10.1016/j.cjca.2017.10.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 10/19/2017] [Accepted: 10/19/2017] [Indexed: 10/18/2022] Open
Abstract
BACKGROUND QT-interval variations in response to exercise-induced increases in heart rate have been reported in children and adults in the diagnosis of long QT syndrome (LQTS). A quick standing challenge has been proposed as an alternative provocative test in adults, with no pediatric data yet available. METHODS A standing test was performed in 100 healthy children (mean age, 9.7 ± 3.1 years) after 10 minutes in a supine position with continuous electrocardiographic recording. QT intervals were measured at baseline, at maximal heart rate, at maximal QT, and at each minute of a 5-minute recovery while standing. Measurements were taken in leads II/V5 and were corrected for heart rate (QTc). RESULTS On standing, the heart rate increased by 29 ± 10 beats per minute (bpm). The QT interval was similar at baseline and on standing (394 ± 34 ms vs 394 ± 34 ms; P = 1.0). However, QTc increased from 426 ± 21 to 509 ± 41 ms (P < 0.001). The 95th percentile for QTc at baseline and maximal heart rate was 457 ms and 563 ms, respectively. At 1 minute of recovery, the QT interval was shorter (375 ± 31 ms) compared with baseline (394 ± 34 ms; P < 0.001) and standing (394 ± 34 ms; P < 0.001). QTc reached baseline values after 1 minute of recovery and remained stable thereafter (423 ± 23 ms at 1 minute; 426 ± 22 ms at 5 minutes; P = 1.0). CONCLUSIONS This first characterization of QTc changes on standing in children shows substantial alterations, which are greater than those seen in adults. Two-thirds of the children would have been misclassified as having LQTS by adult criteria, indicating the need to create child-specific standards.
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Affiliation(s)
- Audrey Dionne
- Division of Cardiology, CHU mère-enfant Sainte-Justine, Université de Montréal, Montréal, Québec, Canada
| | - Anne Fournier
- Division of Cardiology, CHU mère-enfant Sainte-Justine, Université de Montréal, Montréal, Québec, Canada
| | - Nagib Dahdah
- Division of Cardiology, CHU mère-enfant Sainte-Justine, Université de Montréal, Montréal, Québec, Canada
| | - Dominic Abrams
- Electrophysiology Service, Boston Children's Hospital, Harvard University, Boston, MA, USA
| | - Paul Khairy
- Division of Cardiology, CHU mère-enfant Sainte-Justine, Université de Montréal, Montréal, Québec, Canada; Electrophysiology Service and Adult Congenital Heart Center, Montreal Heart Institute, Université de Montréal, Montréal, Québec, Canada
| | - Sylvia Abadir
- Division of Cardiology, CHU mère-enfant Sainte-Justine, Université de Montréal, Montréal, Québec, Canada; Electrophysiology Service and Adult Congenital Heart Center, Montreal Heart Institute, Université de Montréal, Montréal, Québec, Canada.
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Jacquemet V, Gravel H, Curnier D, Vinet A. Theoretical and experimental comparison of lag-based and time-based exponential moving average models of QT hysteresis. Physiol Meas 2017; 38:1885-1905. [PMID: 28885987 DOI: 10.1088/1361-6579/aa8b59] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE In the electrocardiogram, adaptation of the QT interval to variations in heart rate is not instantaneous. Quantification of this hysteresis phenomenon relies on mathematical models describing the relation between the RR and QT time series. These models reproduce hysteresis through an effective RR interval computed as a linear combination of the history of past RR intervals. This filter depends on a time constant parameter that may be used as a biomarker. APPROACH The most common hysteresis model is based on an autoregressive filter with an impulse response that decreases exponentially with the beat number (lag-based model). Recognizing that the QT time series is unevenly spaced, we propose two exponential moving average filters (time-based models) to define the effective RR interval: one with an impulse response that decreases exponentially with time in seconds, and one with a step response that relaxes exponentially with time in seconds. These two filters are neither linear nor time-invariant. Recurrence formulas are derived to enable efficient implementation. MAIN RESULTS Application to clinical signals recorded during tilt table test, exercise and 24 h Holter demonstrates that the three models perform similarly in terms of goodness-of-fit. When comparing the hysteresis time constant in two conditions with different heart rates, however, the time-based models are shown to reduce the bias on the hysteresis time constant caused by heart rate acceleration and deceleration. SIGNIFICANCE Time-based models should be considered when intergroup differences in both heart rate and QT hysteresis are expected.
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Affiliation(s)
- Vincent Jacquemet
- Département de Pharmacologie et Physiologie, Institut de Génie Biomédical, Université de Montréal, Montréal, Canada. Hôpital du Sacré-Coeur de Montréal, Centre de Recherche, Montréal, Canada
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Gravel H, Curnier D, Dahdah N, Jacquemet V. Categorization and theoretical comparison of quantitative methods for assessing QT/RR hysteresis. Ann Noninvasive Electrocardiol 2017; 22. [PMID: 28510313 DOI: 10.1111/anec.12463] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Accepted: 03/27/2017] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND In the human electrocardiogram, there is a lag of adaptation of the QT interval to heart rate changes, usually termed QT/RR hysteresis (QT-hys). Subject-specific quantifiers of QT-hys have been proposed as potential biomarkers, but there is no consensus on the choice of the quantifier. METHODS A comprehensive literature search was conducted to identify original articles reporting quantifiers of repolarization hysteresis from the surface ECG in humans. RESULTS Sixty articles fulfilled our inclusion criteria. Reported biomarkers were grouped under four categories. A simple mathematical model of QT/RR loop was used to illustrate differences between the methods. Category I quantifiers use direct measurement of QT time course of adaptation. They are limited to conditions where RR intervals are under strict control. Category IIa and IIb quantifiers compare QT responses during consecutive heart rate acceleration and deceleration. They are relevant when a QT/RR loop is observed, typically during exercise and recovery, but are not robust to protocol variations. Category III quantifiers evaluate the optimum RR memory in dynamic QT/RR relationship modeling. They estimate an intrinsic memory parameter independent from the nature of RR changes, but their reliability remains to be confirmed when multiple memory parameters are estimated. Promising approaches include the differentiation of short-term and long-term memory and adaptive estimation of memory parameters. CONCLUSION Model-based approaches to QT-hys assessment appear to be the most versatile, as they allow separate quantification of QT/RR dependency and QT-hys, and can be applied to a wide range of experimental settings.
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Affiliation(s)
- Hugo Gravel
- Department of Kinesiology, University of Montreal, Montréal, QC, Canada
| | - Daniel Curnier
- Department of Kinesiology, University of Montreal, Montréal, QC, Canada
| | - Nagib Dahdah
- Division of Pediatric Cardiology and CHU Ste-Justine Research Center, CHU Ste-Justine, Montréal, QC, Canada
| | - Vincent Jacquemet
- Department of Pharmacology and Physiology, Faculty of Medicine, University of Montreal, Montréal, QC, Canada
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Weissler-Snir A, Gollob MH, Chauhan V, Care M, Spears DA. Evaluation of Prolonged QT Interval: Structural Heart Disease Mimicking Long QT Syndrome. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2017; 40:417-424. [PMID: 28155223 DOI: 10.1111/pace.13040] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 12/20/2016] [Accepted: 01/08/2017] [Indexed: 01/19/2023]
Abstract
BACKGROUND In about 20-25% of patients with congenital long QT syndrome (LQTS) a causative pathogenic mutation is not found. The aim of this study was to explore the prevalence of alternative cardiac diagnoses among patients exhibiting prolongation of QT interval with negative genetic testing for LQTS genes. METHODS We conducted a retrospective analysis of 239 consecutive patients who were evaluated in the inherited arrhythmia clinic at the Toronto General Hospital between July 2013 and December 2015 for possible LQTS. A detailed review of the patients' charts, electrocardiograms, and imaging was carried out. RESULTS The analysis included 56 gene-negative patients and 61 gene-positive patients. Of the gene-negative group, 25% had structural heart disease compared to only 1.6% of gene-positive patients (P < 0.001). Structural heart disease was more likely if only one abnormal QTc parameter was found in the course of the evaluation (35.2% vs 9.1%, P = 0.01). The most common structural cardiac pathology was bileaflet mitral valve prolapse (8.9%). No gene-positive patient had episodes of nonsustained ventricular tachycardia, compared to seven of the gene-negative patients (0% vs 12.5%, P = 0.005). CONCLUSIONS Structural pathology was detected in a quarter of gene-negative patients evaluated for possible LQTS. Hence, cardiac imaging and Holter monitoring should be strongly encouraged to rule out structural heart disease in this population.
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Affiliation(s)
- Adaya Weissler-Snir
- Division of Cardiology, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada
| | - Michael H Gollob
- Division of Cardiology, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada
| | - Vijay Chauhan
- Division of Cardiology, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada
| | - Melanie Care
- Division of Cardiology, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada
| | - Danna A Spears
- Division of Cardiology, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada
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36
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The evolution of sports participation guidelines and the influence of genotype–phenotype correlation in long QT syndrome. Trends Cardiovasc Med 2016; 26:690-697. [DOI: 10.1016/j.tcm.2016.04.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 04/29/2016] [Accepted: 04/29/2016] [Indexed: 01/02/2023]
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Steinberg C, Padfield GJ, Champagne J, Sanatani S, Angaran P, Andrade JG, Roberts JD, Healey JS, Chauhan VS, Birnie DH, Janzen M, Gerull B, Klein GJ, Leather R, Simpson CS, Seifer C, Talajic M, Gardner M, Krahn AD. Cardiac Abnormalities in First-Degree Relatives of Unexplained Cardiac Arrest Victims. Circ Arrhythm Electrophysiol 2016; 9:CIRCEP.115.004274. [DOI: 10.1161/circep.115.004274] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Accepted: 08/02/2016] [Indexed: 01/06/2023]
Abstract
Background—
Unexplained cardiac arrest (UCA) may be explained by inherited arrhythmia syndromes. The Cardiac Arrest Survivors With Preserved Ejection Fraction Registry prospectively assessed first-degree relatives of UCA or sudden unexplained death victims to screen for cardiac abnormalities.
Methods and Results—
Around 398 first-degree family members (186 UCA, 212 sudden unexplained death victims’ relatives; mean age, 44±17 years) underwent extensive cardiac workup, including ECG, signal averaged ECG, exercise testing, cardiac imaging, Holter-monitoring, and selective provocative drug testing with epinephrine or procainamide. Genetic testing was performed when a mutation was identified in the UCA survivor or when the diagnostic workup revealed a phenotype suggestive of a specific inherited arrhythmia syndrome. The diagnostic strength was classified as definite, probable, or possible based on previously published definitions. Cardiac abnormalities were detected in 120 of 398 patients (30.2%) with 67 of 398 having a definite or probable diagnosis (17%), including Long-QT syndrome (13%), catecholaminergic polymorphic ventricular tachycardia (4%), arrhythmogenic right ventricular cardiomyopathy (4%), and Brugada syndrome (3%). The detection yield was similar for family members of UCA and sudden unexplained death victims (31% versus 27%;
P
=0.59). Genetic testing was performed more often in family members of UCA patients (29% versus 20%;
P
=0.03). Disease-causing mutations were identified in 20 of 398 relatives (5%). The most common pathogenic mutations were RyR2 (2%), SCN5A (1%), and KNCQ1 (0.8%).
Conclusions—
Cardiac screening revealed abnormalities in 30% of first-degree relatives of UCA or sudden unexplained death victims, with a clear working diagnosis in 17%. Long-QT, arrhythmogenic right ventricular cardiomyopathy, and catecholaminergic polymorphic ventricular tachycardia were the most common diagnoses. Systematic cascade screening and genetic testing in asymptomatic individuals will lead to preventive lifestyle and medical interventions with potential to prevent sudden cardiac death.
Clinical Trial Registration—
URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT00292032.
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Affiliation(s)
| | | | | | | | - Paul Angaran
- For the author affiliations, please see the Appendix
| | | | | | | | | | | | - Mikyla Janzen
- For the author affiliations, please see the Appendix
| | - Brenda Gerull
- For the author affiliations, please see the Appendix
| | | | | | | | | | - Mario Talajic
- For the author affiliations, please see the Appendix
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38
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Waddell-Smith KE, Skinner JR. Update on the Diagnosis and Management of Familial Long QT Syndrome. Heart Lung Circ 2016; 25:769-76. [PMID: 27262388 DOI: 10.1016/j.hlc.2016.01.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 01/20/2016] [Indexed: 01/16/2023]
Abstract
This update was reviewed by the CSANZ Continuing Education and Recertification Committee and ratified by the CSANZ board in August 2015. Since the CSANZ 2011 guidelines, adjunctive clinical tests have proven useful in the diagnosis of LQTS and are discussed in this update. Understanding of the diagnostic and risk stratifying role of LQTS genetics is also discussed. At least 14 LQTS genes are now thought to be responsible for the disease. High-risk individuals may have multiple mutations, large gene rearrangements, C-loop mutations in KCNQ1, transmembrane mutations in KCNH2, or have certain gene modifiers present, particularly NOS1AP polymorphisms. In regards to treatment, nadolol is preferred, particularly for long QT type 2, and short acting metoprolol should not be used. Thoracoscopic left cardiac sympathectomy is valuable in those who cannot adhere to beta blocker therapy, particularly in long QT type 1. Indications for ICD therapies have been refined; and a primary indication for ICD in post-pubertal females with long QT type 2 and a very long QT interval is emerging.
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Affiliation(s)
- Kathryn E Waddell-Smith
- Green Lane Paediatric and Congenital Cardiac Services, Starship Children's Hospital, Auckland New Zealand; The University of Auckland, Department of Child Health, Auckland, New Zealand
| | - Jonathan R Skinner
- Green Lane Paediatric and Congenital Cardiac Services, Starship Children's Hospital, Auckland New Zealand; The University of Auckland, Department of Child Health, Auckland, New Zealand.
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Fenotipo heterogéneo del síndrome de QT largo causado por la mutación KCNH2-H562R: importancia del estudio genético familiar. Rev Esp Cardiol 2015. [DOI: 10.1016/j.recesp.2014.10.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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40
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Refaat MM, Hotait M, Tseng ZH. Utility of the exercise electrocardiogram testing in sudden cardiac death risk stratification. Ann Noninvasive Electrocardiol 2015; 19:311-8. [PMID: 25040480 DOI: 10.1111/anec.12191] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Sudden cardiac death (SCD) remains a major public health problem. Current established criteria identifying those at risk of sudden arrhythmic death, and likely to benefit from implantable cardioverter defibrillators (ICDs), are neither sensitive nor specific. Exercise electrocardiogram (ECG) testing was traditionally used for information concerning patients' symptoms, exercise capacity, cardiovascular function, myocardial ischemia detection, and hemodynamic responses during activity in patients with hypertrophic cardiomyopathy. METHODS We conducted a systematic review of MEDLINE on the utility of exercise ECG testing in SCD risk stratification. RESULTS Exercise testing can unmask suspected primary electrical diseases in certain patients (catecholaminergic polymorphic ventricular tachycardia or concealed long QT syndrome) and can be effectively utilized to risk stratify patients at an increased (such as early repolarization syndrome and Brugada syndrome) or decreased risk of SCD, such as the loss of preexcitation on exercise testing in asymptomatic Wolff-Parkinson-White syndrome. CONCLUSIONS Exercise ECG testing helps in SCD risk stratification in patients with and without arrhythmogenic hereditary syndromes.
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Affiliation(s)
- Marwan M Refaat
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, American University of Beirut Faculty of Medicine and Medical Center, Beirut, Lebanon
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41
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Muñoz-Esparza C, García-Molina E, Salar-Alcaraz M, Peñafiel-Verdú P, Sánchez-Muñoz JJ, Martínez Sánchez J, Cabañas-Perianes V, Valdés Chávarri M, García Alberola A, Gimeno-Blanes JR. Heterogeneous Phenotype of Long QT Syndrome Caused by the KCNH2-H562R Mutation: Importance of Familial Genetic Testing. ACTA ACUST UNITED AC 2015; 68:861-8. [PMID: 25819988 DOI: 10.1016/j.rec.2014.10.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2014] [Accepted: 10/27/2014] [Indexed: 11/15/2022]
Abstract
INTRODUCTION AND OBJECTIVES Long QT syndrome is an inherited ion channelopathy that leads to syncope and sudden death. Because of the heterogeneous phenotype of this disease, genetic testing is fundamental to detect individuals with concealed long QT syndrome. In this study, we determined the features of a family with 13 carriers of the KCNH2-H562R missense mutation, which affects the pore region of the HERG channel. METHODS We identified the KCNH2-H562R mutation in a 65-year-old man with a prolonged QTc interval who had experienced an episode of torsade de pointes. Subsequently, a total of 13 mutation carriers were identified in the family. Carriers (age 48 [26] years; 46% males) underwent clinical evaluation, electrocardiography and echocardiography. RESULTS The mean (standard deviation) QTc in carriers was 493 (42) ms (3 [23%] showed normal QTc); 6 (46%) had symptoms (4, syncope; 1, sudden death; 1, aborted sudden death [proband]). While under treatment with beta-blockers, 11 of 12 carriers (92%) remained asymptomatic at 5 years of follow-up (1 patient required left cardiac sympathectomy). The QTc shortening with beta-blockers was 50 (37) ms. There was 1 sudden death in a patient who refused treatment. CONCLUSIONS Family study is essential in the interpretation of a genetic testing result. This article describes the heterogeneous and variable phenotype of a large family with the KCNH2-H562R mutation and highlights the role of genetic study for the appropriate identification of at-risk individuals who would benefit from treatment.
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Affiliation(s)
- Carmen Muñoz-Esparza
- Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Arrixaca, Universidad de Murcia, IMIB-Arrixaca, El Palmar, Murcia, Spain
| | - Esperanza García-Molina
- Servicio de Análisis Clínicos, Hospital Clínico Universitario Virgen de la Arrixaca, IMIB-Arrixaca, El Palmar, Murcia, Spain
| | - Mariela Salar-Alcaraz
- Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Arrixaca, Universidad de Murcia, IMIB-Arrixaca, El Palmar, Murcia, Spain
| | - Pablo Peñafiel-Verdú
- Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Arrixaca, Universidad de Murcia, IMIB-Arrixaca, El Palmar, Murcia, Spain
| | - Juan J Sánchez-Muñoz
- Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Arrixaca, Universidad de Murcia, IMIB-Arrixaca, El Palmar, Murcia, Spain
| | - Juan Martínez Sánchez
- Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Arrixaca, Universidad de Murcia, IMIB-Arrixaca, El Palmar, Murcia, Spain
| | - Valentín Cabañas-Perianes
- Servicio de Hematología, Hospital Clínico Universitario Virgen de la Arrixaca, Universidad de Murcia, IMIB-Arrixaca, El Palmar, Murcia, Spain
| | - Mariano Valdés Chávarri
- Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Arrixaca, Universidad de Murcia, IMIB-Arrixaca, El Palmar, Murcia, Spain
| | - Arcadio García Alberola
- Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Arrixaca, Universidad de Murcia, IMIB-Arrixaca, El Palmar, Murcia, Spain
| | - Juan R Gimeno-Blanes
- Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Arrixaca, Universidad de Murcia, IMIB-Arrixaca, El Palmar, Murcia, Spain.
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42
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Hanninen M, Klein GJ, Laksman Z, Conacher SS, Skanes AC, Yee R, Gula LJ, Leong-Sit P, Manlucu J, Krahn AD. Reduced Uptake of Family Screening in Genotype-Negative Versus Genotype-Positive Long QT Syndrome. J Genet Couns 2014; 24:558-64. [PMID: 25273952 DOI: 10.1007/s10897-014-9776-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 09/12/2014] [Indexed: 01/08/2023]
Abstract
The acceptance and yield of family screening in genotype-negative long QT syndrome (LQTS) remains incompletely characterized. In this study of family screening for phenotype-definite Long QT Syndrome (LQTS, Schwartz score ≥3.5), probands at a regional Inherited Cardiac Arrhythmia clinic were reviewed. All LQTS patients were offered education by a qualified genetic counselor, along with materials for family screening including electronic and paper correspondence to provide to family members. Thirty-eight qualifying probands were identified and 20 of these had family members who participated in cascade screening. The acceptance of screening was found to be lower among families without a known pathogenic mutation (33 vs. 77 %, p = 0.02). A total of 52 relatives were screened; fewer relatives were screened per index case when the proband was genotype-negative (1.7 vs. 3.1, p = 0.02). The clinical yield of screening appeared to be similar irrespective of gene testing results (38 vs. 33 %, p = 0.69). Additional efforts to promote family screening among gene-negative long QT families may be warranted.
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Affiliation(s)
- Mikael Hanninen
- Division of Cardiology, Grey Nuns Hospital, Edmonton, AB, Canada
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43
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Choudhuri I, Pinninti M, Marwali MR, Sra J, Akhtar M. Polymorphic ventricular tachycardia--part II: the channelopathies. Curr Probl Cardiol 2014; 38:503-48. [PMID: 24262155 DOI: 10.1016/j.cpcardiol.2013.07.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
In this article, we explore the clinical and cellular phenomena of primary electrical diseases of the heart, that is, conditions purely related to ion channel dysfunction and not structural heart disease or reversible acquired causes. This growing classification of conditions, once considered together as "idiopathic ventricular fibrillation," continues to evolve and segregate into diseases that are phenotypically, molecularly, and genetically unique.
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44
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Bennett MT, Gula LJ, Klein GJ, Skanes AC, Yee R, Leong-Sit P, Chattha I, Sy R, Jones DL, Krahn AD. Effect of beta-blockers on QT dynamics in the long QT syndrome: measuring the benefit. ACTA ACUST UNITED AC 2014; 16:1847-51. [DOI: 10.1093/europace/euu086] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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45
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Herman A, Bennett MT, Chakrabarti S, Chakrabarti S, Krahn AD. Life threatening causes of syncope: channelopathies and cardiomyopathies. Auton Neurosci 2014; 184:53-9. [PMID: 24795161 DOI: 10.1016/j.autneu.2014.04.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 04/04/2014] [Accepted: 04/14/2014] [Indexed: 01/08/2023]
Abstract
Syncope is common, has a high recurrence rate and carries a risk of morbidity and, dependent on the cause, mortality. Although the majority of patients with syncope have a benign prognosis, syncope as a result of cardiomyopathy or channelopathy carries a poor prognosis. In addition, the identification of these disorders allows for the institution of treatments, which are effective at reducing the risk of both syncope and mortality. It is for these reasons that the identification of a cardiomyopathy or channelopathy in patients with syncope is crucial. This review article will describe the characteristics of common cardiomyopathies and channelopathies and their investigation.
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Affiliation(s)
- Adam Herman
- Division of Cardiology, University of British Columbia, Vancouver, BC, Canada
| | - Matthew T Bennett
- Division of Cardiology, University of British Columbia, Vancouver, BC, Canada
| | | | | | - Andrew D Krahn
- Division of Cardiology, University of British Columbia, Vancouver, BC, Canada.
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Abstract
Cardiogenic seizures are common and could be the sentinel event heralding the presence of congenital long QT syndrome (LQTS). Distinguishing a cardiogenic seizure from a neurogenic one is of the utmost importance. Herein, we present the case of a 12-year-old boy with recurrent episodes of syncope and seizures. Despite absence of QT prolongation on electrocardiogram, absence of documented arrhythmias, a negative LQTS genetic test, and recurrent episodes while on nadolol beta-blocker therapy, he was diagnosed with LQTS and implanted with an implantable cardioverter defibrillator (ICD). When syncope and seizure occurred with normal sinus rhythm documented on the ICD, he was referred to neurology, and an electroencephalogram was positive for numerous bursts of bilaterally synchronous generalized discharges. He was started on antiepileptic treatment after which his seizures resolved. His LQTS diagnosis was removed, beta-blocker therapy discontinued, and his ICD was explanted. He has been seizure-free for over 2 years.
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Affiliation(s)
- Beth A Medford
- Departments of Pediatric and Adolescent Medicine/Division of Pediatric Cardiology, Mayo Clinic, Rochester, Minn, USA
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47
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Aziz PF, Wieand TS, Ganley J, Henderson J, McBride M, Shah MJ. Do LQTS gene single nucleotide polymorphisms alter QTc intervals at rest and during exercise stress testing? Ann Noninvasive Electrocardiol 2013; 18:288-93. [PMID: 23714088 DOI: 10.1111/anec.12037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND The impact of harboring, genetic variants or single nucleotide polymorphisms (LQT-PM) on the repolarization response during exercise and recovery is unknown. OBJECTIVE To assess the QTc interval adaptation during exercise stress testing (EST) in children with LQT polymorphisms compared to a group of age and gender matched normal controls. METHODS One hundred forty-eight patients were age and gender matched into two groups: LQT-PM and control. Each patient underwent a uniform exercise protocol employing a cycle ergometer followed by a 9 minute recovery phase with continuous 12-lead electrocardiogram (ECG) monitoring. Intervals (RR, QT and QTc) at rest (supine), peak exercise and in recovery (1, 3, 5, 7, and 9 minutes) were measured. RESULTS Forty-three patients were positive for LQT-PM and the control group consisted of 105 patients. A total of 83 SNPs were identified: SCN5A n = 31 (37%), KCNE1 n = 29 (35%), KCNH2 n = 20 (24%), KCNQ1 n = 2 (2%) and KCNE2 n = 1 (1%). The QTc interval measurements of the LQT-PM were longer at rest, peak exercise and all phases of recovery when compared to the control group. Neither group demonstrated abnormal QTc interval adaptation in response to exercise. Patients with homozygous SNPs had longer resting QTc intervals when compared to patients with only heterozygous SNPs (435 ± 23 ms vs. 415 ± 20 ms, respectively, P value <0.006). CONCLUSIONS Individuals with LQT-PM may have longer QTc intervals at rest as well as at peak exercise and all phases of the recovery period compared to normal controls. Additionally, subjects with homozygous SNPs had longer resting QTc intervals when compared to those with only heterozygous SNPs.
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Affiliation(s)
- Peter F Aziz
- Cleveland Clinic Foundation, Department of Pediatric Cardiology and the Cleveland Clinic Lerner College of Medicine, Cleveland, OH, USA.
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48
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Abstract
Unexplained cardiac arrest is defined as a cardiac arrest in the absence of coronary artery disease and overt structural heart disease, present in 5%-10% of cardiac arrest survivors. A genetic contribution to cardiac arrest is more common in this population, most commonly attributed to an inherited ion channel abnormality leading to familial syncope and sudden death. The common causes are Long QT and Brugada syndrome, catecholaminergic ventricular tachycardia, idiopathic ventricular fibrillation, and early repolarization syndrome. Latent structural causes include inherited cardiomyopathy such as arrhythmogenic right ventricular cardiomyopathy. We review these causes in detail and a structured approach to the investigation of these patients, which provides a diagnosis in approximately half of these patients. This allows for the initiation of disease-specific treatments and enables family screening.
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49
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Krahn AD, Healey JS, Chauhan VS, Birnie DH, Champagne J, Sanatani S, Ahmad K, Ballantyne E, Gerull B, Yee R, Skanes AC, Gula LJ, Leong-Sit P, Klein GJ, Gollob MH, Simpson CS, Talajic M, Gardner M. Epinephrine Infusion in the Evaluation of Unexplained Cardiac Arrest and Familial Sudden Death. Circ Arrhythm Electrophysiol 2012; 5:933-40. [DOI: 10.1161/circep.112.973230] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Epinephrine infusion may unmask latent genetic conditions associated with cardiac arrest, including long-QT syndrome and catecholaminergic polymorphic ventricular tachycardia (VT).
Methods and Results—
Patients with unexplained cardiac arrest (normal left ventricular function and QT interval) and selected family members from the Cardiac Arrest Survivors with Preserved Ejection Fraction Registry (CASPER) registry underwent epinephrine challenge at doses of 0.05, 0.10, and 0.20 μg/kg per minute. A test was considered positive for long-QT syndrome if the absolute QT interval prolonged by ≥30 ms at 0.10 μg/kg per minute and borderline if QT prolongation was 1 to 29 ms. Catecholaminergic polymorphic VT was diagnosed if epinephrine provoked ≥3 beats of polymorphic or bidirectional VT and borderline if polymorphic couplets, premature ventricular contractions, or nonsustained monomorphic VT was induced. Epinephrine infusion was performed in 170 patients (age, 42±16 years; 49% men), including 98 patients with unexplained cardiac arrest. Testing was positive for long-QT syndrome in 31 patients (18%) and borderline in 24 patients (14%). Exercise testing provoked an abnormal QT response in 42% of tested patients with a positive epinephrine response. Testing for catecholaminergic polymorphic VT was positive in 7% and borderline in 5%. Targeted genetic testing of abnormal patients was positive in 17% of long-QT syndrome patients and 13% of catecholaminergic polymorphic VT patients.
Conclusions—
Epinephrine challenge provoked abnormalities in a substantial proportion of patients, most commonly a prolonged QT interval. Exercise and genetic testing replicated the diagnosis suggested by the epinephrine response in a small proportion of patients. Epinephrine infusion combined with exercise testing and targeted genetic testing is recommended in the workup of suspected familial sudden death syndromes.
Clinical Trial Registration—
URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT00292032.
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Affiliation(s)
- Andrew D. Krahn
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Jeffrey S. Healey
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Vijay S. Chauhan
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - David H. Birnie
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Jean Champagne
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Shubhayan Sanatani
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Kamran Ahmad
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Emily Ballantyne
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Brenda Gerull
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Raymond Yee
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Allan C. Skanes
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Lorne J. Gula
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Peter Leong-Sit
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - George J. Klein
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Michael H. Gollob
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Christopher S. Simpson
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Mario Talajic
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
| | - Martin Gardner
- From the University of British Columbia (A.D.K.), Vancouver, BC; Population Health Research Institute, McMaster University (J.S.H.), Hamilton, ON; University Health Network (V.S.C.), Toronto, Canada; University of Ottawa Heart Institute (D.H.B., M.H.G.), Ottawa, ON; Quebec Heart Institute (J.C.), Laval Hospital, Quebec City, PQ; BC Children’s Hospital (S.S.), Vancouver, British Columbia, Vancouver, BC; St Michael’s Hospital (K.A.), Toronto, Canada; University of Western Ontario (E.B., R.Y., A.C.S.,
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Obeyesekere MN, Leong-Sit P, Gula LJ, Yee R, Skanes AC, Klein GJ, Krahn AD. The Evaluation of a Borderline Long QT Interval in an Asymptomatic Patient. Card Electrophysiol Clin 2012; 4:227-238. [PMID: 26939820 DOI: 10.1016/j.ccep.2012.02.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
QT prolongation on resting electrocardiography (ECG) is common, and the clinician is often challenged by the dilemma of excluding acquired causes and recognizing potential congenital long QT syndrome (LQTS). The hallmark of LQTS is an abnormally long QT interval. However, a normal or borderline long QT interval may be observed in up to 50% of patients with LQTS because of the intermittent nature of QT prolongation. This review presents an approach to evaluating the asymptomatic patient with a borderline long QT interval, which incorporates a comprehensive clinical assessment, rest and provocative ECG testing, and genetic testing when appropriate.
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Affiliation(s)
- Manoj N Obeyesekere
- Division of Cardiology, The University of Western Ontario, 339 Windermere Road, London, Ontario N6A 5A5, Canada
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