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Albertini L, Spears DA. Management of arrythmias during pregnancy. Heart 2023:heartjnl-2023-322746. [PMID: 37993263 DOI: 10.1136/heartjnl-2023-322746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2023] Open
Affiliation(s)
- Lisa Albertini
- Cardiology, Toronto General Hospital, Toronto, Ontario, Canada
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Albertini L, Spears DA. Management of arrhythmias during pregnancy. Heart Rhythm O2 2023; 4:597-598. [PMID: 37936664 PMCID: PMC10626184 DOI: 10.1016/j.hroo.2023.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023] Open
Affiliation(s)
- Lisa Albertini
- Toronto General Hospital, University Health Network Toronto, Ontario, Canada
| | - Danna A. Spears
- Toronto General Hospital, University Health Network Toronto, Ontario, Canada
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Suszko AM, Chakraborty P, Viswanathan K, Barichello S, Sapp JL, Talajic M, Laksman Z, Yee R, Spears DA, Adler A, Chauhan VS. PO-668-06 AUTOMATED QUANTIFICATION OF ABNORMAL LOW-AMPLITUDE QRS PEAKS FROM HIGH-RESOLUTION ECGS PREDICTS LATE VENTRICULAR ARRHYTHMIAS IN HYPERTROPHIC CARDIOMYOPATHY: A 5-YEAR PROSPECTIVE MULTICENTER STUDY. Heart Rhythm 2022. [DOI: 10.1016/j.hrthm.2022.03.392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Chatterjee D, Pieroni M, Fatah M, Charpentier F, Cunningham KS, Spears DA, Chatterjee D, Suna G, Bos JM, Ackerman MJ, Schulze-Bahr E, Dittmann S, Notarstefano PG, Bolognese L, Duru F, Saguner AM, Hamilton RM. An autoantibody profile detects Brugada syndrome and identifies abnormally expressed myocardial proteins. Eur Heart J 2021; 41:2878-2890. [PMID: 32533187 DOI: 10.1093/eurheartj/ehaa383] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 03/23/2020] [Accepted: 04/24/2020] [Indexed: 12/17/2022] Open
Abstract
AIMS Brugada syndrome (BrS) is characterized by a unique electrocardiogram (ECG) pattern and life-threatening arrhythmias. However, the Type 1 Brugada ECG pattern is often transient, and a genetic cause is only identified in <25% of patients. We sought to identify an additional biomarker for this rare condition. As myocardial inflammation may be present in BrS, we evaluated whether myocardial autoantibodies can be detected in these patients. METHODS AND RESULTS For antibody (Ab) discovery, normal human ventricular myocardial proteins were solubilized and separated by isoelectric focusing (IEF) and molecular weight on two-dimensional (2D) gels and used to discover Abs by plating with sera from patients with BrS and control subjects. Target proteins were identified by mass spectrometry (MS). Brugada syndrome subjects were defined based on a consensus clinical scoring system. We assessed discovery and validation cohorts by 2D gels, western blots, and ELISA. We performed immunohistochemistry on myocardium from BrS subjects (vs. control). All (3/3) 2D gels exposed to sera from BrS patients demonstrated specific Abs to four proteins, confirmed by MS to be α-cardiac actin, α-skeletal actin, keratin, and connexin-43, vs. 0/8 control subjects. All (18/18) BrS subjects from our validation cohorts demonstrated the same Abs, confirmed by western blots, vs. 0/24 additional controls. ELISA optical densities for all Abs were elevated in all BrS subjects compared to controls. In myocardium obtained from BrS subjects, each protein, as well as SCN5A, demonstrated abnormal protein expression in aggregates. CONCLUSION A biomarker profile of autoantibodies against four cardiac proteins, namely α-cardiac actin, α-skeletal actin, keratin, and connexin-43, can be identified from sera of BrS patients and is highly sensitive and specific, irrespective of genetic cause for BrS. The four involved proteins, along with the SCN5A-encoded Nav1.5 alpha subunit are expressed abnormally in the myocardium of patients with BrS.
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Affiliation(s)
- Diptendu Chatterjee
- Department of Pediatrics, The Labatt Family Heart Centre and Translational Medicine, The Hospital for Sick Children & Research Institute and the University of Toronto, Room 1725D, 555 University Avenue, Toronto, ON M5G 1X8, Canada
| | - Maurizio Pieroni
- Cardiovascular Department, San Donato Hospital, Via Curtatone 54 - 52100 Arezzo, Italy
| | - Meena Fatah
- Department of Pediatrics, The Labatt Family Heart Centre and Translational Medicine, The Hospital for Sick Children & Research Institute and the University of Toronto, Room 1725D, 555 University Avenue, Toronto, ON M5G 1X8, Canada
| | - Flavien Charpentier
- L'Institut du Thorax, INSERM, CNRS, UNIV Nantes, 8 quai Moncousu, 44007 Nantes, France
| | - Kristopher S Cunningham
- Department of Laboratory Medicine and Pathobiology, University of Toronto, 27 King's College Circle, Toronto, Ontario M5S 1A1, Canada
| | - Danna A Spears
- Department of Medicine, University Health Network-Toronto General Hospital, 200 Elizabeth Street 4NU-492, Toronto, Ontario M5G 2C4, Canada
| | - Dipashree Chatterjee
- Department of Psychology, University of Toronto, 27 King's College Circle, Toronto, Ontario M5S 1A1, Canada
| | - Gonca Suna
- Department of Cardiology, University Heart Center Zurich, Rämistrasse 100, 8091 Zürich, Switzerland
| | - J Martjin Bos
- Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Windland Smith Rice Genetic Heart Rhythm Clinic, Mayo Clinic, Rochester, MN, USA.,Department of Pediatric and Adolescent Medicine, Division of Pediatric Cardiology, Mayo Clinic, Rochester, MN, USA.,Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, MN, USA
| | - Michael J Ackerman
- Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Windland Smith Rice Genetic Heart Rhythm Clinic, Mayo Clinic, Rochester, MN, USA.,Department of Pediatric and Adolescent Medicine, Division of Pediatric Cardiology, Mayo Clinic, Rochester, MN, USA.,Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, MN, USA
| | - Eric Schulze-Bahr
- Institute for Genetics of Heart Diseases, Department für Kardiologie und Angiologie, Zentrum für Innere Medizin, Universitätsklinikum Münster Albert-Schweitzer-Campus 1, Gebäude D3 48149 Münster, Germany
| | - Sven Dittmann
- Institute for Genetics of Heart Diseases, Department für Kardiologie und Angiologie, Zentrum für Innere Medizin, Universitätsklinikum Münster Albert-Schweitzer-Campus 1, Gebäude D3 48149 Münster, Germany
| | | | - Leonardo Bolognese
- Cardiovascular Department, San Donato Hospital, Via Curtatone 54 - 52100 Arezzo, Italy
| | - Firat Duru
- Department of Cardiology, University Heart Center Zurich, Rämistrasse 100, 8091 Zürich, Switzerland
| | - Ardan M Saguner
- Department of Cardiology, University Heart Center Zurich, Rämistrasse 100, 8091 Zürich, Switzerland
| | - Robert M Hamilton
- Department of Pediatrics, The Labatt Family Heart Centre and Translational Medicine, The Hospital for Sick Children & Research Institute and the University of Toronto, Room 1725D, 555 University Avenue, Toronto, ON M5G 1X8, Canada
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5
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Abstract
The most common arrhythmias detected during pregnancy include sinus tachycardia, sinus bradycardia, and sinus arrhythmia, identified in 0.1% of pregnancies. Isolated premature atrial or ventricular arrhythmias are observed in 0.03% of pregnancies. Arrhythmias may become more frequent during pregnancy or may manifest for the first time.
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Affiliation(s)
| | - Danna A Spears
- University Health Network - Toronto General Hospital, Toronto, Canada
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6
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Chatterjee D, Fatah M, Akdis D, Spears DA, Koopmann TT, Mittal K, Rafiq MA, Cattanach BM, Zhao Q, Healey JS, Ackerman MJ, Bos JM, Sun Y, Maynes JT, Brunckhorst C, Medeiros-Domingo A, Duru F, Saguner AM, Hamilton RM. An autoantibody identifies arrhythmogenic right ventricular cardiomyopathy and participates in its pathogenesis. Eur Heart J 2019; 39:3932-3944. [PMID: 30239670 DOI: 10.1093/eurheartj/ehy567] [Citation(s) in RCA: 100] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 08/21/2018] [Indexed: 12/26/2022] Open
Abstract
Aims Arrhythmogenic right ventricular cardiomyopathy (ARVC) is characterized by right ventricular myocardial replacement and life-threatening ventricular arrhythmias. Desmosomal gene mutations are sometimes identified, but clinical and genetic diagnosis remains challenging. Desmosomal skin disorders can be caused by desmosomal gene mutations or autoantibodies. We sought to determine if anti-desmosome antibodies are present in subjects with ARVC. Methods and results We evaluated ARVC subjects and controls for antibodies to cardiac desmosomal cadherin proteins. Desmoglein-2 (DSG2), desmocollin-2, and N-cadherin proteins on western blots were exposed to sera, in primary and validation cohorts of subjects and controls, as well as the naturally occurring Boxer dog model of ARVC. We identified anti-DSG2 antibodies in 12/12 and 25/25 definite ARVC cohorts and 7/8 borderline subjects. Antibody was absent in 11/12, faint in 1/12, and absent in 20/20 of two control cohorts. Anti-DSG2 antibodies were present in 10/10 Boxer dogs with ARVC, and absent in 18/18 without. In humans, the level of anti-DSG2 antibodies correlated with the burden of premature ventricular contractions (r = 0.70), and antibodies caused gap junction dysfunction, a common feature of ARVC, in vitro. Anti-DSG2 antibodies were present in ARVC subjects regardless of whether an underlying mutation was identified, or which mutation was present. A disease-specific DSG2 epitope was identified. Conclusion Anti-DSG2 antibodies are a sensitive and specific biomarker for ARVC. The development of autoimmunity as a result of target-related mutations is unique. Anti-DSG2 antibodies likely explain the cardiac inflammation that is frequently identified in ARVC and may represent a new therapeutic target.
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Affiliation(s)
- Diptendu Chatterjee
- The Labatt Family Heart Centre (Department of Pediatrics) and Translational Medicine, The Hospital for Sick Children & Research Institute and the University of Toronto, Room 1725D, 555 University Avenue, Toronto, Ontario, Canada
| | - Meena Fatah
- The Labatt Family Heart Centre (Department of Pediatrics) and Translational Medicine, The Hospital for Sick Children & Research Institute and the University of Toronto, Room 1725D, 555 University Avenue, Toronto, Ontario, Canada
| | - Deniz Akdis
- Zurich ARVC Program, University Heart Centre Zurich Department of Cardiology, Rämistrasse 100, Zurich, Switzerland
| | - Danna A Spears
- University Health Network, Toronto General Hospital Electrophysiology Department, 200 Elizabeth Street, Toronto, Ontario, Canada
| | - Tamara T Koopmann
- The Labatt Family Heart Centre (Department of Pediatrics) and Translational Medicine, The Hospital for Sick Children & Research Institute and the University of Toronto, Room 1725D, 555 University Avenue, Toronto, Ontario, Canada
| | - Kirti Mittal
- The Labatt Family Heart Centre (Department of Pediatrics) and Translational Medicine, The Hospital for Sick Children & Research Institute and the University of Toronto, Room 1725D, 555 University Avenue, Toronto, Ontario, Canada
| | - Muhammad A Rafiq
- The Labatt Family Heart Centre (Department of Pediatrics) and Translational Medicine, The Hospital for Sick Children & Research Institute and the University of Toronto, Room 1725D, 555 University Avenue, Toronto, Ontario, Canada
| | - Bruce M Cattanach
- MRC Mammalian Genetics Unit, MRC Harwell Institute, Harwell Science and Innovation Campus, Oxfordshire, UK
| | - Qili Zhao
- University of Toronto Department of Mechanical and Industrial Engineering, Kings College Road, Toronto, Ontario, Canada
| | - Jeff S Healey
- Population Health Research Institute and McMaster University Department of Medicine (Division of Cardiology), 237 Barton Street East, Hamilton, Ontario, Canada
| | - Michael J Ackerman
- Mayo Clinic College of Medicine Department of Cardiovascular Medicine, 200 1st St SW, Rochester, MN, USA
| | - Johan Martijn Bos
- Mayo Clinic College of Medicine Department of Cardiovascular Medicine, 200 1st St SW, Rochester, MN, USA
| | - Yu Sun
- University of Toronto Department of Mechanical and Industrial Engineering, Kings College Road, Toronto, Ontario, Canada.,Institute of Biomaterials and Biomedical Engineering, University of Toronto, Rosebrugh Building (RS), 164 College Street, Room 40, Toronto, Ontario, Canada
| | - Jason T Maynes
- The Hospital for Sick Children and the University of Toronto Department of Anesthesia and Pain Medicine, 555 University Avenue, Toronto, Ontario, Canada
| | - Corinna Brunckhorst
- Zurich ARVC Program, University Heart Centre Zurich Department of Cardiology, Rämistrasse 100, Zurich, Switzerland
| | | | - Firat Duru
- Zurich ARVC Program, University Heart Centre Zurich Department of Cardiology, Rämistrasse 100, Zurich, Switzerland.,Center for Integrative Human Physiology, University of Zurich, Winterthurerstr. 190, Zurich, Switzerland
| | - Ardan M Saguner
- Zurich ARVC Program, University Heart Centre Zurich Department of Cardiology, Rämistrasse 100, Zurich, Switzerland
| | - Robert M Hamilton
- The Labatt Family Heart Centre (Department of Pediatrics) and Translational Medicine, The Hospital for Sick Children & Research Institute and the University of Toronto, Room 1725D, 555 University Avenue, Toronto, Ontario, Canada
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Weissler-Snir A, Allan K, Cunningham K, Connelly KA, Lee DS, Spears DA, Rakowski H, Dorian P. Hypertrophic Cardiomyopathy–Related Sudden Cardiac Death in Young People in Ontario. Circulation 2019; 140:1706-1716. [DOI: 10.1161/circulationaha.119.040271] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background:
Hypertrophic cardiomyopathy (HCM) is considered a leading cause of sudden cardiac death (SCD) in younger people. The incidence of HCM-related SCD and its relationship to exercise have not been well studied in large comprehensive studies outside of tertiary care settings. This study sought to estimate the incidence of HCM-related SCD and its association with exercise in a large unselected population.
Methods:
Using the Office of the Chief Coroner of Ontario database encompassing all deaths attended by the coroner, we identified all HCM-related SCDs in individuals 10 to 45 years of age between 2005 and 2016 (70 million person-years). Confirmation of HCM was based on typical macroscopic and microscopic features (definite HCM-related SCD). Sudden deaths with a prior clinical diagnosis of HCM but no autopsy were considered probable HCM-related SCDs. Cases with typical features but no myofiber disarray were considered possible HCM. The completeness of data was verified in a subset of patients in the Toronto area with the use of a registry of all emergency medical services–attended cardiac arrests, with an autopsy rate of 94%. To estimate the number of HCM-related aborted cardiac arrests and lives potentially saved by implantable cardioverter-defibrillators, all de novo implantations for secondary prevention and all implantations and appropriate shocks for primary prevention in patients with HCM 10 to 45 years of age, respectively, were identified with the use of a registry containing data on implantable cardioverter-defibrillator implantations from all implanting sites throughout Ontario.
Results:
Forty-four, 3, and 6 cases of definite, probable, and possible HCM-related SCDs, respectively, were identified, corresponding to estimated annual incidence rates of 0.31 per 1000 HCM person-years (95% CI, 0.24–0.44) for definite HCM-related SCD, 0.33 per 1000 HCM person-years (95% CI, 0.34–0.62) for definite or probable HCM-related SCD, and 0.39 per 1000 HCM person-years (95% CI, 0.28–0.49) for definite, probable, or possible HCM-related SCD (estimated 140 740 HCM person-years of observation). The estimated annual incidence rate for HCM-related SCD plus aborted cardiac arrest and HCM-related life-threatening arrhythmia (SCD, aborted cardiac arrest, and appropriate implantable cardioverter-defibrillator shocks) was 0.84 per 1000 HCM person-years (95% CI, 0.70–1.0). The majority (70%) of SCDs occurred in previously undiagnosed individuals. Most SCDs occurred during rest (64.8%) or light activity (18.5%).
Conclusions:
The incidence of HCM-related SCD in the general population 10 to 45 years of age is substantially lower than previously reported, with most cases occurring in previously undiagnosed individuals. SCDs are infrequently related to exercise.
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Affiliation(s)
- Adaya Weissler-Snir
- Division of Cardiology (A.W.S., K.A., K.A.C., P.D.), St Michael’s Hospital, Toronto, Canada
- Department of Medicine (A.W.S., K.A., K.A.C., P.D., D.S.L., D.A.S., H.R.), University of Toronto, Canada
| | - Katherine Allan
- Division of Cardiology (A.W.S., K.A., K.A.C., P.D.), St Michael’s Hospital, Toronto, Canada
- Department of Medicine (A.W.S., K.A., K.A.C., P.D., D.S.L., D.A.S., H.R.), University of Toronto, Canada
| | - Kristopher Cunningham
- Ontario Forensic Pathology Service, Department of Laboratory Medicine and Pathobiology (K.C.), University of Toronto, Canada
| | - Kim A. Connelly
- Division of Cardiology (A.W.S., K.A., K.A.C., P.D.), St Michael’s Hospital, Toronto, Canada
- Department of Medicine (A.W.S., K.A., K.A.C., P.D., D.S.L., D.A.S., H.R.), University of Toronto, Canada
| | - Douglas S. Lee
- Department of Medicine (A.W.S., K.A., K.A.C., P.D., D.S.L., D.A.S., H.R.), University of Toronto, Canada
- Division of Cardiology, University Health Network, Peter Munk Cardiac Centre, Toronto General Hospital, Canada (D.S.L., D.A.S., H.R)
- Institute for Clinical Evaluative Sciences, Toronto, Canada (D.S.L.)
| | - Danna A. Spears
- Department of Medicine (A.W.S., K.A., K.A.C., P.D., D.S.L., D.A.S., H.R.), University of Toronto, Canada
- Division of Cardiology, University Health Network, Peter Munk Cardiac Centre, Toronto General Hospital, Canada (D.S.L., D.A.S., H.R)
| | - Harry Rakowski
- Department of Medicine (A.W.S., K.A., K.A.C., P.D., D.S.L., D.A.S., H.R.), University of Toronto, Canada
- Division of Cardiology, University Health Network, Peter Munk Cardiac Centre, Toronto General Hospital, Canada (D.S.L., D.A.S., H.R)
| | - Paul Dorian
- Division of Cardiology (A.W.S., K.A., K.A.C., P.D.), St Michael’s Hospital, Toronto, Canada
- Keenan Research Centre of the Li Ka Shing Knowledge Institute (P.D.), St Michael’s Hospital, Toronto, Canada
- Department of Medicine (A.W.S., K.A., K.A.C., P.D., D.S.L., D.A.S., H.R.), University of Toronto, Canada
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8
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Cunningham KS, Spears DA, Care M. Evaluation of cardiac hypertrophy in the setting of sudden cardiac death. Forensic Sci Res 2019; 4:223-240. [PMID: 31489388 PMCID: PMC6713129 DOI: 10.1080/20961790.2019.1633761] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 06/17/2019] [Accepted: 06/17/2019] [Indexed: 01/06/2023] Open
Abstract
Ventricular hypertrophy is a common pathological finding at autopsy that can act as a substrate for arrhythmogenesis. Pathologists grapple with the significance of ventricular hypertrophy when assessing the sudden and unexpected deaths of young people and what it could mean for surviving family members. The pathological spectrum of left ventricular hypertrophy (LVH) is reviewed herein. This article is oriented to the practicing autopsy pathologist to help make sense of various patterns of increased heart muscle, particularly those that are not clearly cardiomyopathic, yet present in the setting of sudden cardiac death. The article also reviews factors influencing arrhythmogenesis as well as genetic mutations most commonly associated with ventricular hypertrophy, especially those associated with hypertrophic cardiomyopathy (HCM).
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Affiliation(s)
- Kristopher S Cunningham
- Department of Laboratory Medicine and Pathobiology, Ontario Forensic Pathology Service, University of Toronto, Toronto, Canada
| | - Danna A Spears
- University Health Network, Division of Cardiology - Electrophysiology, University of Toronto, Toronto, Canada
| | - Melanie Care
- Fred A. Litwin Family Centre in Genetic Medicine and Inherited Arrhythmia Clinic, University Health Network & Mount Sinai Hospital, University of Toronto, Toronto, Canada
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9
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Roberts JD, Murphy NP, Hamilton RM, Lubbers ER, James CA, Kline CF, Gollob MH, Krahn AD, Sturm AC, Musa H, El-Refaey M, Koenig S, Aneq MÅ, Hoorntje ET, Graw SL, Davies RW, Rafiq MA, Koopmann TT, Aafaqi S, Fatah M, Chiasson DA, Taylor MR, Simmons SL, Han M, van Opbergen CJ, Wold LE, Sinagra G, Mittal K, Tichnell C, Murray B, Codima A, Nazer B, Nguyen DT, Marcus FI, Sobriera N, Lodder EM, van den Berg MP, Spears DA, Robinson JF, Ursell PC, Green AK, Skanes AC, Tang AS, Gardner MJ, Hegele RA, van Veen TA, Wilde AA, Healey JS, Janssen PM, Mestroni L, van Tintelen JP, Calkins H, Judge DP, Hund TJ, Scheinman MM, Mohler PJ. Ankyrin-B dysfunction predisposes to arrhythmogenic cardiomyopathy and is amenable to therapy. J Clin Invest 2019; 129:3171-3184. [PMID: 31264976 PMCID: PMC6668697 DOI: 10.1172/jci125538] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 05/14/2019] [Indexed: 01/11/2023] Open
Abstract
Arrhythmogenic cardiomyopathy (ACM) is an inherited arrhythmia syndrome characterized by severe structural and electrical cardiac phenotypes, including myocardial fibrofatty replacement and sudden cardiac death. Clinical management of ACM is largely palliative, owing to an absence of therapies that target its underlying pathophysiology, which stems partially from our limited insight into the condition. Following identification of deceased ACM probands possessing ANK2 rare variants and evidence of ankyrin-B loss of function on cardiac tissue analysis, an ANK2 mouse model was found to develop dramatic structural abnormalities reflective of human ACM, including biventricular dilation, reduced ejection fraction, cardiac fibrosis, and premature death. Desmosomal structure and function appeared preserved in diseased human and murine specimens in the presence of markedly abnormal β-catenin expression and patterning, leading to identification of a previously unknown interaction between ankyrin-B and β-catenin. A pharmacological activator of the WNT/β-catenin pathway, SB-216763, successfully prevented and partially reversed the murine ACM phenotypes. Our findings introduce what we believe to be a new pathway for ACM, a role of ankyrin-B in cardiac structure and signaling, a molecular link between ankyrin-B and β-catenin, and evidence for targeted activation of the WNT/β-catenin pathway as a potential treatment for this disease.
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Affiliation(s)
- Jason D. Roberts
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Western University, London, Ontario, Canada
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, UCSF, San Francisco, California, USA
| | - Nathaniel P. Murphy
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Departments of Physiology and Cell Biology and Internal Medicine, Division of Cardiovascular Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Robert M. Hamilton
- The Labatt Family Heart Centre (Department of Pediatrics) and Translational Medicine, The Hospital for Sick Children and the University of Toronto, Toronto, Ontario, Canada
| | - Ellen R. Lubbers
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Departments of Physiology and Cell Biology and Internal Medicine, Division of Cardiovascular Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Cynthia A. James
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Crystal F. Kline
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Departments of Physiology and Cell Biology and Internal Medicine, Division of Cardiovascular Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Michael H. Gollob
- Peter Munk Cardiac Centre, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Andrew D. Krahn
- Heart Rhythm Services, Division of Cardiology, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Amy C. Sturm
- Genomic Medicine Institute, Geisinger, Danville, Pennsylvania, USA
| | - Hassan Musa
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Mona El-Refaey
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Sara Koenig
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Meriam Åström Aneq
- Department of Clinical Physiology and Department of Medical and Health Sciences, Linköping University, Linköping, Sweden
| | - Edgar T. Hoorntje
- Netherlands Heart Institute, Utrecht, Netherlands
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Sharon L. Graw
- Cardiovascular Institute and Adult Medical Genetics Program, University of Colorado Denver, Aurora, Colorado, USA
| | - Robert W. Davies
- Program in Genetics and Genome Biology and The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Muhammad Arshad Rafiq
- The Labatt Family Heart Centre (Department of Pediatrics) and Translational Medicine, The Hospital for Sick Children and the University of Toronto, Toronto, Ontario, Canada
- Department of Bioscience, COMSATS University, Islamabad, Pakistan
| | - Tamara T. Koopmann
- The Labatt Family Heart Centre (Department of Pediatrics) and Translational Medicine, The Hospital for Sick Children and the University of Toronto, Toronto, Ontario, Canada
| | - Shabana Aafaqi
- The Labatt Family Heart Centre (Department of Pediatrics) and Translational Medicine, The Hospital for Sick Children and the University of Toronto, Toronto, Ontario, Canada
| | - Meena Fatah
- The Labatt Family Heart Centre (Department of Pediatrics) and Translational Medicine, The Hospital for Sick Children and the University of Toronto, Toronto, Ontario, Canada
| | - David A. Chiasson
- Pediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Matthew R.G. Taylor
- Cardiovascular Institute and Adult Medical Genetics Program, University of Colorado Denver, Aurora, Colorado, USA
| | - Samantha L. Simmons
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Departments of Physiology and Cell Biology and Internal Medicine, Division of Cardiovascular Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Mei Han
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Departments of Physiology and Cell Biology and Internal Medicine, Division of Cardiovascular Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Chantal J.M. van Opbergen
- Department of Medical Physiology, Division of Heart and Lungs, University Medical Center, Utrecht, Utrecht University, Utrecht, Netherlands
| | - Loren E. Wold
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Departments of Physiology and Cell Biology and Internal Medicine, Division of Cardiovascular Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | | | - Kirti Mittal
- The Labatt Family Heart Centre (Department of Pediatrics) and Translational Medicine, The Hospital for Sick Children and the University of Toronto, Toronto, Ontario, Canada
| | - Crystal Tichnell
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Brittney Murray
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Alberto Codima
- Department of Medicine, University of Sao Paulo, Sao Paulo, Brazil
| | - Babak Nazer
- Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - Duy T. Nguyen
- Section of Cardiac Electrophysiology, Division of Cardiology, University of Colorado, Aurora, Colorado, USA
| | - Frank I. Marcus
- Division of Cardiology, Sarver Heart Center, University of Arizona, Tucson, Arizona, USA
| | - Nara Sobriera
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Elisabeth M. Lodder
- Amsterdam University Medical Center, University of Amsterdam, Heart Centre, Department of Clinical and Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam, Netherlands
| | - Maarten P. van den Berg
- Department of Cardiology, University of Groningen, University Medical Centre Groningen, Groningen, Netherlands
| | - Danna A. Spears
- Peter Munk Cardiac Centre, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada
| | - John F. Robinson
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | | | - Anna K. Green
- Departments of Clinical Genetics and Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Allan C. Skanes
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Western University, London, Ontario, Canada
| | - Anthony S. Tang
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Western University, London, Ontario, Canada
| | - Martin J. Gardner
- Division of Cardiology, Department of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Robert A. Hegele
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
- Department of Medicine, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Toon A.B. van Veen
- Department of Medical Physiology, Division of Heart and Lungs, University Medical Center, Utrecht, Utrecht University, Utrecht, Netherlands
| | - Arthur A.M. Wilde
- Amsterdam University Medical Center, University of Amsterdam, Heart Centre, Department of Clinical and Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam, Netherlands
| | - Jeff S. Healey
- Population Health Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Paul M.L. Janssen
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Departments of Physiology and Cell Biology and Internal Medicine, Division of Cardiovascular Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Luisa Mestroni
- Cardiovascular Institute and Adult Medical Genetics Program, University of Colorado Denver, Aurora, Colorado, USA
| | - J. Peter van Tintelen
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
- Amsterdam UMC, University of Amsterdam, Department of Clinical Genetics, Amsterdam, Netherlands
- Department of Genetics, University Medical Center Utrecht (UMCU), Utrecht, Netherlands
| | - Hugh Calkins
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Daniel P. Judge
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
- Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Thomas J. Hund
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, Ohio, USA
| | - Melvin M. Scheinman
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, UCSF, San Francisco, California, USA
| | - Peter J. Mohler
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Departments of Physiology and Cell Biology and Internal Medicine, Division of Cardiovascular Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
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Weissler‐Snir A, Hindieh W, Spears DA, Adler A, Rakowski H, Chan RH. The relationship between the quantitative extent of late gadolinium enhancement and burden of nonsustained ventricular tachycardia in hypertrophic cardiomyopathy: A delayed contrast‐enhanced magnetic resonance study. J Cardiovasc Electrophysiol 2019; 30:651-657. [DOI: 10.1111/jce.13855] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 01/15/2019] [Accepted: 01/19/2019] [Indexed: 01/17/2023]
Affiliation(s)
- Adaya Weissler‐Snir
- Division of CardiologyPeter Munk Cardiac Centre, Toronto General Hospital, University Health NetworkToronto Ontario Canada
| | - Waseem Hindieh
- Division of CardiologyPeter Munk Cardiac Centre, Toronto General Hospital, University Health NetworkToronto Ontario Canada
| | - Danna A. Spears
- Division of CardiologyPeter Munk Cardiac Centre, Toronto General Hospital, University Health NetworkToronto Ontario Canada
| | - Arnon Adler
- Division of CardiologyPeter Munk Cardiac Centre, Toronto General Hospital, University Health NetworkToronto Ontario Canada
| | - Harry Rakowski
- Division of CardiologyPeter Munk Cardiac Centre, Toronto General Hospital, University Health NetworkToronto Ontario Canada
| | - Raymond H. Chan
- Division of CardiologyPeter Munk Cardiac Centre, Toronto General Hospital, University Health NetworkToronto Ontario Canada
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11
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Spears DA. Implantable Cardioverter-Defibrillator Therapy in Brugada Syndrome. JACC Clin Electrophysiol 2019; 5:149-151. [DOI: 10.1016/j.jacep.2018.10.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 10/18/2018] [Indexed: 11/25/2022]
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12
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Rafiq MA, Chaudhry A, Care M, Spears DA, Morel CF, Hamilton RM. Whole exome sequencing identified 1 base pair novel deletion in BCL2-associated athanogene 3 (BAG3) gene associated with severe dilated cardiomyopathy (DCM) requiring heart transplant in multiple family members. Am J Med Genet A 2017; 173:699-705. [PMID: 28211974 DOI: 10.1002/ajmg.a.38087] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 11/15/2016] [Indexed: 02/03/2023]
Abstract
Dilated cardiomyopathy (DCM) is characterized by dilation and impaired contraction of the left ventricle or both ventricles. Among hereditary DCM, the genetic causes are heterogeneous, and include mutations encoding cytoskeletal, nucleoskeletal, mitochondrial, and calcium-handling proteins. We report three severely affected males, in a four-generation pedigree, with DCM phenotype who underwent cardiac transplant. Cardiomegaly with marked biventricular dilation and fibrosis were noticeable histopathological findings. The affected males had tested negative on a 46-gene pancardiomyopathy panel. Whole Exome Sequencing (WES) was performed to reveal mutation in the gene responsible in generation of DCM phenotypes. The 1-bp (Chr10:121435979delC; c.913delC) novel heterozygous deletion in exon 4 of BAG3, was identified in three affected males, resulted in frame-shift and a premature termination codon (p.Met306-Stop) producing a truncated BAG3 protein lacking functionally important PXXP and BAG domains. WES data were further utilized to map 10 SNP markers around the discovered mutation to generate shared disease haplotype in all affected individuals encompassing 11 Mb on 10q25.3-26.2 harboring BAG3. Finally genotypes were inferred for the unavailable/deceased individuals in the pedigrees. Here we propose that Chr10:121435979delC in BAG3 is a causal mutation in these subjects. Our and earlier studies indicate that BAG3 mutations are associated with DCM phenotypes. BAG3 should be added to cardiomyopathy gene panels for screening of DCM patients, and patients previously considered gene elusive should undergo sequencing of the BAG3 gene. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Muhammad Arshad Rafiq
- Physiology and Experimental Medicine, The Hospital for Sick Children and Research Institute, Toronto, Ontario, Canada.,Department of Bio-Sciences, COMSATS Institute of Information Technology (CIIT), Islamabad, Pakistan
| | - Ayeshah Chaudhry
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Melanie Care
- Fred A. Litwin Family Center in Genetic Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Danna A Spears
- Division of Cardiology, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Chantal F Morel
- Fred A. Litwin Family Center in Genetic Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Robert M Hamilton
- Physiology and Experimental Medicine, The Hospital for Sick Children and Research Institute, Toronto, Ontario, Canada
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13
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Das M, Suszko AM, Nayyar S, Viswanathan K, Spears DA, Tomlinson G, Pinter A, Crystal E, Dalvi R, Krishnan S, Chauhan VS. Automated Quantification of Low-Amplitude Abnormal QRS Peaks From High-Resolution ECG Recordings Predicts Arrhythmic Events in Patients With Cardiomyopathy. Circ Arrhythm Electrophysiol 2017; 10:CIRCEP.116.004874. [PMID: 28705874 DOI: 10.1161/circep.116.004874] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 06/08/2017] [Indexed: 11/16/2022]
Abstract
BACKGROUND Cardiomyopathy patients are at risk of sudden death, typically from scar-related abnormalities of electrical activation that promote ventricular tachyarrhythmias. Abnormal intra-QRS peaks may provide a measure of altered activation. We hypothesized that quantification of such QRS peaks (QRSp) in high-resolution ECGs would predict arrhythmic events in implantable cardioverter-defibrillator (ICD)-eligible cardiomyopathy patients. METHODS AND RESULTS Ninety-nine patients with ischemic or non-ischemic dilated cardiomyopathy undergoing prophylactic ICD implantation were prospectively enrolled (age 62±11 years, left ventricular ejection fraction 27±7%). High-resolution (1024 Hz) digital 12-lead ECGs were recorded during intrinsic rhythm. QRSp was quantified for each precordial lead as the total number of low-amplitude deflections that deviated from their respective naive QRS template. The primary end point of arrhythmic events was defined as appropriate ICD therapy or sustained ventricular tachyarrhythmias. After a median follow-up of 24 (15-43) months, 20 (20%) patients had arrhythmic events. Both QRSp and QRS duration were greater in those with arrhythmic events (both P<0.001) and this was consistent for QRSp for both cardiomyopathy types. In a multivariable Cox regression model that included age, left ventricular ejection fraction, QRS duration, and QRSp, only QRSp was an independent predictor of arrhythmic events (hazard ratio, 2.1; P<0.001). Receiver operating characteristic analysis revealed that a QRSp ≥2.25 identified arrhythmic events with greater sensitivity (100% versus 70%, P<0.05) and negative predictive value (100% versus 89%, P<0.05) than QRS duration ≥120 ms. CONCLUSIONS QRSp measured from high-resolution digital 12-lead ECGs independently predicts ventricular tachyarrhythmias in ICD-eligible cardiomyopathy patients. This novel QRS morphology index has the potential to improve sudden death risk stratification and patient selection for prophylactic ICD therapy.
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Affiliation(s)
- Moloy Das
- From the Peter Munk Cardiac Center, Division of Cardiology, University Health Network, Toronto, Ontario, Canada (M.D., A.M.S., S.N., K.V., D.A.S., G.T., R.D., V.S.C.); Department of Cardiology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom (M.D.); Division of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada (A.P.); Division of Cardiology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada (E.C.); and Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada (S.K.)
| | - Adrian M Suszko
- From the Peter Munk Cardiac Center, Division of Cardiology, University Health Network, Toronto, Ontario, Canada (M.D., A.M.S., S.N., K.V., D.A.S., G.T., R.D., V.S.C.); Department of Cardiology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom (M.D.); Division of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada (A.P.); Division of Cardiology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada (E.C.); and Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada (S.K.)
| | - Sachin Nayyar
- From the Peter Munk Cardiac Center, Division of Cardiology, University Health Network, Toronto, Ontario, Canada (M.D., A.M.S., S.N., K.V., D.A.S., G.T., R.D., V.S.C.); Department of Cardiology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom (M.D.); Division of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada (A.P.); Division of Cardiology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada (E.C.); and Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada (S.K.)
| | - Karthik Viswanathan
- From the Peter Munk Cardiac Center, Division of Cardiology, University Health Network, Toronto, Ontario, Canada (M.D., A.M.S., S.N., K.V., D.A.S., G.T., R.D., V.S.C.); Department of Cardiology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom (M.D.); Division of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada (A.P.); Division of Cardiology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada (E.C.); and Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada (S.K.)
| | - Danna A Spears
- From the Peter Munk Cardiac Center, Division of Cardiology, University Health Network, Toronto, Ontario, Canada (M.D., A.M.S., S.N., K.V., D.A.S., G.T., R.D., V.S.C.); Department of Cardiology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom (M.D.); Division of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada (A.P.); Division of Cardiology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada (E.C.); and Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada (S.K.)
| | - George Tomlinson
- From the Peter Munk Cardiac Center, Division of Cardiology, University Health Network, Toronto, Ontario, Canada (M.D., A.M.S., S.N., K.V., D.A.S., G.T., R.D., V.S.C.); Department of Cardiology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom (M.D.); Division of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada (A.P.); Division of Cardiology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada (E.C.); and Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada (S.K.)
| | - Arnold Pinter
- From the Peter Munk Cardiac Center, Division of Cardiology, University Health Network, Toronto, Ontario, Canada (M.D., A.M.S., S.N., K.V., D.A.S., G.T., R.D., V.S.C.); Department of Cardiology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom (M.D.); Division of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada (A.P.); Division of Cardiology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada (E.C.); and Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada (S.K.)
| | - Eugene Crystal
- From the Peter Munk Cardiac Center, Division of Cardiology, University Health Network, Toronto, Ontario, Canada (M.D., A.M.S., S.N., K.V., D.A.S., G.T., R.D., V.S.C.); Department of Cardiology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom (M.D.); Division of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada (A.P.); Division of Cardiology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada (E.C.); and Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada (S.K.)
| | - Rupin Dalvi
- From the Peter Munk Cardiac Center, Division of Cardiology, University Health Network, Toronto, Ontario, Canada (M.D., A.M.S., S.N., K.V., D.A.S., G.T., R.D., V.S.C.); Department of Cardiology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom (M.D.); Division of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada (A.P.); Division of Cardiology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada (E.C.); and Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada (S.K.)
| | - Sridhar Krishnan
- From the Peter Munk Cardiac Center, Division of Cardiology, University Health Network, Toronto, Ontario, Canada (M.D., A.M.S., S.N., K.V., D.A.S., G.T., R.D., V.S.C.); Department of Cardiology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom (M.D.); Division of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada (A.P.); Division of Cardiology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada (E.C.); and Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada (S.K.)
| | - Vijay S Chauhan
- From the Peter Munk Cardiac Center, Division of Cardiology, University Health Network, Toronto, Ontario, Canada (M.D., A.M.S., S.N., K.V., D.A.S., G.T., R.D., V.S.C.); Department of Cardiology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom (M.D.); Division of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada (A.P.); Division of Cardiology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada (E.C.); and Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada (S.K.).
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Gabarin N, Jaeggi ET, Spears DA, Sermer M, Silversides CK, Bhagra CJ. Concurrent maternal and fetal tachyarrhythmia in pregnancy. Obstet Med 2017; 10:195-197. [PMID: 29225683 DOI: 10.1177/1753495x17702016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 02/23/2017] [Indexed: 11/16/2022] Open
Abstract
The occurrence of a maternal and fetal tachyarrhythmia together in pregnancy is exceedingly rare. We report a case of a persistent fetal atrial ectopic tachycardia occurring in conjunction with a maternal atrial tachycardia with left ventricular systolic dysfunction. Amiodarone was effective in treating both maternal and fetal arrhythmias.
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Affiliation(s)
- Nadia Gabarin
- Division of Cardiology, Pregnancy and Heart Disease Program, Mount Sinai Hospital, University of Toronto, Toronto, Canada
| | - Edgar T Jaeggi
- Division of Cardiology, Fetal Cardiac Program, Labatt Family Heart Centre, The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Danna A Spears
- Division of Cardiology, Pregnancy and Heart Disease Program, Mount Sinai Hospital, University of Toronto, Toronto, Canada
| | - Mathew Sermer
- Department of Obstetrics and Gynecology, Division of Maternal and Fetal Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Canada
| | - Candice K Silversides
- Division of Cardiology, Pregnancy and Heart Disease Program, Mount Sinai Hospital, University of Toronto, Toronto, Canada
| | - Catriona J Bhagra
- Division of Cardiology, Pregnancy and Heart Disease Program, Mount Sinai Hospital, University of Toronto, Toronto, Canada
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15
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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 Clin Electrophysiol 2017; 40:417-424. [PMID: 28155223 DOI: 10.1111/pace.13040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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16
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Porta-Sánchez A, Spillane DR, Harris L, Xue J, Dorsey P, Care M, Chauhan V, Gollob MH, Spears DA. T-Wave Morphology Analysis in Congenital Long QT Syndrome Discriminates Patients From Healthy Individuals. JACC Clin Electrophysiol 2016; 3:374-381. [PMID: 29759450 DOI: 10.1016/j.jacep.2016.10.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 10/18/2016] [Accepted: 10/20/2016] [Indexed: 10/20/2022]
Abstract
OBJECTIVES This study aims to assess the capability of T-wave analysis to: 1) identify genotype-positive long QT syndrome (LQTS) patients; 2) identify LQTS patients with borderline or normal QTc interval (≤460 ms); and 3) classify LQTS subtype. BACKGROUND LQTS often presents with a nondiagnostic electrocardiogram (ECG). T-wave abnormalities may be the only marker of this potentially lethal arrhythmia syndrome. METHODS ECGs taken at rest in 108 patients (43 with LQTS1, 20 with LQTS2, and 45 control subjects) were evaluated for T-wave flatness, asymmetry, and notching, which produces a morphology combination score (MCS) of the 3 features (MCS = 1.6 × flatness + asymmetry + notch) using QT Guard Plus Software (GE Healthcare, Milwaukee, Wisconsin). To assess for heterogeneity of repolarization, the principal component analysis ratio 2 (PCA-2) was calculated. RESULTS Mean QTc intervals were 486 ± 50 ms (LQTS1), 479 ± 36 ms (LQTS2), and 418 ± 24 ms (control subjects) (p < 0.05). MCS and PCA-2 differed between LQTS patients and control subjects (MCS: 117.8 ± 57.4 vs. 71.9 ± 16.2; p < 0.001; PCA-2: 20.2 ± 10.4% vs. 14.6 ± 5.5%; p < 0.001), LQTS1 and LQTS2 patients (MCS: 96.3 ± 28.7 vs. 164 ± 75.2; p < 0.001; PCA-2: 17.8 ± 8.3% vs. 25 ± 12.6%; p < 0.001), and between LQTS patients with borderline or normal QTc intervals (n = 17) and control subjects (MCS: 105.7 ± 49.9 vs. 71.9 ± 16.2; p < 0.001; PCA-2: 18.1 ± 7.2% vs. 14.6 ± 5.5%; p < 0.001). T-wave metrics were consistent across multiple ECGs from individual patients based on the average intraclass correlation coefficient (MCS: 0.96; PCA-2: 0.86). CONCLUSIONS Automated T-wave morphology analysis accurately discriminates patients with pathogenic LQTS mutations from control subjects and between the 2 most common LQTS subtypes. Mutation carriers without baseline QTc prolongation were also identified. This may be a useful tool for screening families of LQTS patients, particularly when the QTc interval is subthreshold and genetic testing is unavailable.
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Affiliation(s)
- Andreu Porta-Sánchez
- Division of Cardiology, Peter Munk Cardiac Center, University Health Network, Toronto, Ontario, Canada
| | - David R Spillane
- Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Louise Harris
- Division of Cardiology, Peter Munk Cardiac Center, University Health Network, Toronto, Ontario, Canada
| | - Joel Xue
- GE Healthcare, Wauwatosa, Wisconsin
| | | | | | - Vijay Chauhan
- Division of Cardiology, Peter Munk Cardiac Center, University Health Network, Toronto, Ontario, Canada
| | - Michael H Gollob
- Division of Cardiology, Peter Munk Cardiac Center, University Health Network, Toronto, Ontario, Canada
| | - Danna A Spears
- Division of Cardiology, Peter Munk Cardiac Center, University Health Network, Toronto, Ontario, Canada.
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17
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Weissler-Snir A, Chan RH, Adler A, Care M, Chauhan V, Gollob MH, Ziv-Baran T, Fourey D, Hindieh W, Rakowski H, Spears DA. Usefulness of 14-Day Holter for Detection of Nonsustained Ventricular Tachycardia in Patients With Hypertrophic Cardiomyopathy. Am J Cardiol 2016; 118:1258-1263. [PMID: 27567133 DOI: 10.1016/j.amjcard.2016.07.043] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 07/21/2016] [Accepted: 07/21/2016] [Indexed: 10/21/2022]
Abstract
Nonsustained ventricular tachycardia (NSVT), defined as ≥3 consecutive ventricular beats at ≥120 beats/min lasting <30 seconds, is an independent predictor of sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HC). Current guidelines recommend 24- to 48-hour Holter monitoring as part of SCD risk stratification. We sought to assess the difference in diagnostic yield of 14-day Holter monitoring compared to 24-48 hours for the detection of NSVT and to assess the prevalence and characteristics of NSVT in patients with HC with prolonged monitoring. We retrospectively analyzed the 14-day Holter monitors of 77 patients with HC from May 2014 to March 2016. Number of episodes and maximal length and rate on each day were recorded. NSVT was detected in 75.3% of patients during 14-day Holter monitoring. The median number of runs was 2 (range 0 to 26 runs). The median number of beats of the longest run was 10.5 (range 3 to 68 beats) with a mean maximum rate of 159.5 ± 20.8.4 beats/min (range 102 to 203 beats/min). First episodes of NSVT were detected throughout the 14 days, with only 22.5% and 44.8% of the episodes captured within the first 24 and 48 hours of monitoring, respectively. In conclusion, prolonged Holter monitoring revealed ≥1 episode of NSVT in 75% of patients with HC of which <50% were detected within the first 48 hours. Hence, prolonged Holter monitoring may be superior for SCD risk stratification in HC. However, the high prevalence of NSVT in this population may limit its utility in evaluating the risk for SCD of the individual patient.
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18
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Adler A, Sadek MM, Chan AY, Dell E, Rutberg J, Davis D, Green MS, Spears DA, Gollob MH. Patient Outcomes From a Specialized Inherited Arrhythmia Clinic. Circ Arrhythm Electrophysiol 2016; 9:e003440. [DOI: 10.1161/circep.115.003440] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Arnon Adler
- From the Inherited Arrhythmia Research Program, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada (A.A., A.Y.M.C., D.A.S., M.H.G.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (M.M.S., E.D., J.R., D.D., M.S.G.)
| | - Mouhannad M. Sadek
- From the Inherited Arrhythmia Research Program, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada (A.A., A.Y.M.C., D.A.S., M.H.G.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (M.M.S., E.D., J.R., D.D., M.S.G.)
| | - Anita Y.M. Chan
- From the Inherited Arrhythmia Research Program, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada (A.A., A.Y.M.C., D.A.S., M.H.G.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (M.M.S., E.D., J.R., D.D., M.S.G.)
| | - Edith Dell
- From the Inherited Arrhythmia Research Program, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada (A.A., A.Y.M.C., D.A.S., M.H.G.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (M.M.S., E.D., J.R., D.D., M.S.G.)
| | - Julie Rutberg
- From the Inherited Arrhythmia Research Program, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada (A.A., A.Y.M.C., D.A.S., M.H.G.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (M.M.S., E.D., J.R., D.D., M.S.G.)
| | - Darryl Davis
- From the Inherited Arrhythmia Research Program, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada (A.A., A.Y.M.C., D.A.S., M.H.G.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (M.M.S., E.D., J.R., D.D., M.S.G.)
| | - Martin S. Green
- From the Inherited Arrhythmia Research Program, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada (A.A., A.Y.M.C., D.A.S., M.H.G.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (M.M.S., E.D., J.R., D.D., M.S.G.)
| | - Danna A. Spears
- From the Inherited Arrhythmia Research Program, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada (A.A., A.Y.M.C., D.A.S., M.H.G.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (M.M.S., E.D., J.R., D.D., M.S.G.)
| | - Michael H. Gollob
- From the Inherited Arrhythmia Research Program, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada (A.A., A.Y.M.C., D.A.S., M.H.G.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (M.M.S., E.D., J.R., D.D., M.S.G.)
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Abstract
A sudden unexplained death is felt to be due to a primary arrhythmic disorder when no structural heart disease is found on autopsy, and there is no preceding documentation of heart disease. In these cases, death is presumed to be secondary to a lethal and potentially heritable abnormality of cardiac ion channel function. These channelopathies include congenital long QT syndrome, catecholaminergic polymorphic ventricular tachycardia, Brugada syndrome, and short QT syndrome. In certain cases, genetic testing may have an important role in supporting a diagnosis of a primary arrhythmia disorder, and can also provide prognostic information, but by far the greatest strength of genetic testing lies in the screening of family members, who may be at risk. The purpose of this review is to describe the basic genetic and molecular pathophysiology of the primary inherited arrhythmia disorders, and to outline a rational approach to genetic testing, management, and family screening.
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Affiliation(s)
- Danna A Spears
- Division of Cardiology - Electrophysiology, University Health Network, Toronto General Hospital, Toronto, ON, Canada
| | - Michael H Gollob
- Division of Cardiology - Electrophysiology, University Health Network, Toronto General Hospital, Toronto, ON, Canada
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Silversides CK, Spears DA. Atrial Fibrillation and Atrial Flutter in Pregnant Women With Heart Disease. JACC Clin Electrophysiol 2015; 1:293-295. [DOI: 10.1016/j.jacep.2015.07.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 07/01/2015] [Accepted: 07/06/2015] [Indexed: 10/23/2022]
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Crean AM, Spears DA, Suszko AM, Chauhan VS. High-resolution 3D scar imaging using a novel late iodine enhancement multidetector CT protocol to guide ventricular tachycardia catheter ablation. J Cardiovasc Electrophysiol 2012; 24:708-10. [PMID: 23217083 DOI: 10.1111/jce.12047] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 10/22/2012] [Accepted: 10/29/2012] [Indexed: 11/26/2022]
Abstract
Scar delineation with late gadolinium-enhanced MRI can direct VT substrate mapping and ablation, but imaging is poor and relatively contraindicated in the majority of patients with ICDs. We present a case of scar definition using late iodine-enhanced multidetector CT in a patient with ischemic cardiomyopathy and multiple ICD shocks for VT. CT images were acquired using a novel intracoronary contrast delivery protocol which provided high-resolution subendocardial scar visualization. The segmented scar images were subsequently imported into an electroanatomic mapping platform to guide successful VT ablation.
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Affiliation(s)
- Andrew M Crean
- Division of Cardiology, University Health Network, Toronto, Ontario, Canada
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22
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Spears DA, Suszko AM, Dalvi R, Crean AM, Ivanov J, Nanthakumar K, Downar E, Chauhan VS. Relationship of bipolar and unipolar electrogram voltage to scar transmurality and composition derived by magnetic resonance imaging in patients with nonischemic cardiomyopathy undergoing VT ablation. Heart Rhythm 2012; 9:1837-46. [PMID: 22846338 DOI: 10.1016/j.hrthm.2012.07.022] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Indexed: 12/31/2022]
Abstract
BACKGROUND Bipolar voltage mapping has a role in defining endocardial-based scar in postinfarct patients undergoing ventricular tachycardia catheter ablation. The utility of bipolar and unipolar voltages in characterizing scar has not been evaluated in patients with nonischemic cardiomyopathy. OBJECTIVE To relate left ventricular (LV) endocardial bipolar and unipolar voltages in these patients to scar transmurality (endocardial vs nonendocardial) and composition (homogeneous core vs heterogeneous gray). METHODS Ten consecutive cardiomyopathy patients undergoing endocardial LV tachycardia ablation were included (age 48 ± 14 years; left ventricular ejection fraction 43% ± 15%). Preablation late gadolinium-enhanced magnetic resonance imaging was used to quantify core and gray scar by using signal-intensity thresholding. Electroanatomic LV endocardial mapping provided bipolar and unipolar voltages. Electroanatomic maps and late gadolinium-enhanced magnetic resonance imaging were rigidly registered in order to relate voltage to scar (registration error 3.6 ± 2.9 mm). RESULTS Bipolar voltage was lower in endocardial core than in no scar (P <.001). Unipolar voltage was lower in endocardial core and nonendocardial core than in no scar (P <.001). Endocardial and nonendocardial gray scar had an effect similar to that of core in reducing bipolar and unipolar voltages (P <.001). The mass of healthy myocardium and endocardial core scar independently predicted bipolar and unipolar voltages using general estimating equation modeling. With receiver operating characteristic curve analysis, bipolar voltage >1.9 mV and unipolar voltage <6.7 mV had a high negative predictive value (91%) for detecting nonendocardial scar from either endocardial scar or no scar. CONCLUSIONS In patients with nonischemic cardiomyopathy, LV endocardial bipolar voltage is dependent on endocardial core and gray scar, while the unipolar voltage is influenced by core and gray scar across the LV wall as defined by late gadolinium-enhanced magnetic resonance imaging.
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Affiliation(s)
- Danna A Spears
- Division of Cardiology, University Health Network, Toronto, Ontario, Canada
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Spears DA, Suszko AM, Krahn AD, Selvaraj RJ, Ivanov J, Chauhan VS. Latent microvolt T-wave alternans in survivors of unexplained cardiac arrest unmasked by epinephrine challenge. Heart Rhythm 2012; 9:1076-82. [PMID: 22373794 DOI: 10.1016/j.hrthm.2012.02.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Indexed: 12/01/2022]
Abstract
BACKGROUND The arrhythmogenic substrate in survivors of unexplained cardiac arrest (UCA) has not been defined. OBJECTIVES To test the hypothesis that patients with UCA have latent repolarization abnormalities, in particular T-wave alternans (TWA), which may be unmasked with epinephrine (EPI) challenge. METHODS We prospectively studied 10 UCA survivors (46 ± 9 years) and 11 first-degree relatives (FDRs) of sudden death victims (37 ± 14 years). Patients with UCA underwent standard clinical testing, which was normal. FDRs had normal clinical history and testing. All subjects underwent an EPI infusion (0.05, 0.1, and 0.2 μg/(kg·min), 5 minutes each dose) while recording continuous digital 12-lead electrocardiograms. Corrected QT interval and QT variability index were evaluated at each EPI dose. TWA magnitude (V(alt)) was assessed at each dose by using the spectral method. Positive (+) TWA at each dose was defined as V(alt) > 0 with k ≥ 3 in 1 or more 128-beat segment in ≥2 electrocardiogram leads. A novel metric, TWA burden, reflecting V(alt) integrated over time (s), was also evaluated for each EPI dose. RESULTS There was no difference between UCA survivors and FDRs with respect to heart rate, QT, corrected QT interval, or QT variability index at baseline or during EPI. At baseline, +TWA was similar between UCA survivors and FDRs (10% vs 0%; P = NS). During EPI, +TWA was more prevalent in UCA survivors than in FDRs (80% vs 18%; P = .009). TWA burden was greater in UCA survivors than in FDRs during EPI 0.1 (P = .039) and EPI 0.2 μg/(kg·min) (P = .009). CONCLUSIONS UCA survivors are more likely to demonstrate latent TWA compared with FDRs, which becomes manifest with EPI. This novel finding provides evidence for an arrhythmogenic substrate in UCA survivors.
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Affiliation(s)
- Danna A Spears
- Division of Cardiology, University Health Network, Toronto, Ontario, Canada
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Spears DA, Zlotnik J, Robertson E, Gordon N. Integration of care and caring. Could you provide information on what the role of social services should be in long-term care facilities? Contemp Longterm Care 1992; 15:28, 85. [PMID: 10123051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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