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Amr A, Koelemen J, Reich C, Sedaghat-Hamedani F, Kayvanpour E, Haas J, Frese K, Lehmann D, Katus HA, Frey N, Meder B. Improving sudden cardiac death risk stratification in hypertrophic cardiomyopathy using established clinical variables and genetic information. Clin Res Cardiol 2024; 113:728-736. [PMID: 37792019 PMCID: PMC11026183 DOI: 10.1007/s00392-023-02310-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 09/14/2023] [Indexed: 10/05/2023]
Abstract
BACKGROUND AND AIMS The cardiac societies of Europe and the United States have established different risk models for preventing sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM). The aim of this study is to validate current SCD risk prediction methods in a German HCM cohort and to improve them by the addition of genotype information. METHODS HCM patients without prior SCD or equivalent arrhythmic events ≥ 18 years of age were enrolled in an expert cardiomyopathy center in Germany. The primary endpoint was defined as SCD/-equivalent within 5 years of baseline evaluation. 5-year SCD-risk estimates and recommendations for ICD implantations, as defined by the ESC and AHA/ACC guidelines, were analyzed. Multivariate cox proportional hazards analyses were integrated with genetic findings as additive SCD risk. RESULTS 283 patients were included and followed for in median 5.77 years (2.92; 8.85). A disease-causing variant was found in 138 (49%) patients. 14 (5%) patients reached the SCD endpoint (5-year incidence 4.9%). Kaplan-Meier survival analysis shows significantly lower overall SCD event-free survival for patients with an identified disease-causing variant (p < 0.05). The ESC HCM Risk-SCD model showed an area-under-the-curve (AUC) of 0.74 (95% CI 0.68-0.79; p < 0.0001) with a sensitivity of 0.29 (95% CI 0.08-0.58) and specificity of 0.83 (95% CI 0.78-0.88) for a risk estimate ≥ 6%/5-years. By comparison, the AHA/ACC HCM SCD risk stratification model showed an AUC of 0.70 (95% CI 0.65-0.76; p = 0.003) with a sensitivity of 0.93 (95% CI, 0.66-0.998) and specificity of 0.28 (95% CI 0.23-0.34) at the respective cut-off. The modified SCD Risk Score with genetic information yielded an AUC of 0.76 (95% CI 0.71-0.81; p < 0.0001) with a sensitivity of 0.86 (95% CI 0.57-0.98) and specificity of 0.69 (95% CI 0.63-0.74). The number-needed-to-treat (NNT) to prevent 1 SCD event by prophylactic ICD-implantation is 13 for the ESC model, 28 for AHA/ACC and 9 for the modified Genotype-model. CONCLUSION This study confirms the performance of current risk models in clinical decision making. The integration of genetic findings into current SCD risk stratification methods seem feasible and can add in decision making, especially in borderline risk-groups. A subgroup of patients with high SCD risk remains unidentified by current risk scores.
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Affiliation(s)
- Ali Amr
- Institute for Cardiomyopathies & Center for Cardiogenetics, Department of Medicine III, University of Heidelberg, Im Neuenheimer Feld 410, 69120, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), Standort Heidelberg/Mannheim, 69120, Heidelberg, Germany
| | - Jan Koelemen
- Institute for Cardiomyopathies & Center for Cardiogenetics, Department of Medicine III, University of Heidelberg, Im Neuenheimer Feld 410, 69120, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), Standort Heidelberg/Mannheim, 69120, Heidelberg, Germany
| | - Christoph Reich
- Institute for Cardiomyopathies & Center for Cardiogenetics, Department of Medicine III, University of Heidelberg, Im Neuenheimer Feld 410, 69120, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), Standort Heidelberg/Mannheim, 69120, Heidelberg, Germany
| | - Farbod Sedaghat-Hamedani
- Institute for Cardiomyopathies & Center for Cardiogenetics, Department of Medicine III, University of Heidelberg, Im Neuenheimer Feld 410, 69120, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), Standort Heidelberg/Mannheim, 69120, Heidelberg, Germany
| | - Elham Kayvanpour
- Institute for Cardiomyopathies & Center for Cardiogenetics, Department of Medicine III, University of Heidelberg, Im Neuenheimer Feld 410, 69120, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), Standort Heidelberg/Mannheim, 69120, Heidelberg, Germany
| | - Jan Haas
- Institute for Cardiomyopathies & Center for Cardiogenetics, Department of Medicine III, University of Heidelberg, Im Neuenheimer Feld 410, 69120, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), Standort Heidelberg/Mannheim, 69120, Heidelberg, Germany
| | - Karen Frese
- Institute for Cardiomyopathies & Center for Cardiogenetics, Department of Medicine III, University of Heidelberg, Im Neuenheimer Feld 410, 69120, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), Standort Heidelberg/Mannheim, 69120, Heidelberg, Germany
| | - David Lehmann
- Institute for Cardiomyopathies & Center for Cardiogenetics, Department of Medicine III, University of Heidelberg, Im Neuenheimer Feld 410, 69120, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), Standort Heidelberg/Mannheim, 69120, Heidelberg, Germany
| | - Hugo A Katus
- Institute for Cardiomyopathies & Center for Cardiogenetics, Department of Medicine III, University of Heidelberg, Im Neuenheimer Feld 410, 69120, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), Standort Heidelberg/Mannheim, 69120, Heidelberg, Germany
| | - Norbert Frey
- Institute for Cardiomyopathies & Center for Cardiogenetics, Department of Medicine III, University of Heidelberg, Im Neuenheimer Feld 410, 69120, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), Standort Heidelberg/Mannheim, 69120, Heidelberg, Germany
| | - Benjamin Meder
- Institute for Cardiomyopathies & Center for Cardiogenetics, Department of Medicine III, University of Heidelberg, Im Neuenheimer Feld 410, 69120, Heidelberg, Germany.
- DZHK (German Centre for Cardiovascular Research), Standort Heidelberg/Mannheim, 69120, Heidelberg, Germany.
- Stanford Genome Technology Center, Stanford University School of Medicine, Palo Alto, CA, 94305, USA.
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2
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Wong J, Peters S, Marwick TH. Phenotyping heart failure by genetics and associated conditions. Eur Heart J Cardiovasc Imaging 2023; 24:1293-1301. [PMID: 37279791 DOI: 10.1093/ehjci/jead125] [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: 05/12/2023] [Accepted: 05/26/2023] [Indexed: 06/08/2023] Open
Abstract
Heart failure is a highly heterogeneous disease, and genetic testing may allow phenotypic distinctions that are incremental to those obtainable from imaging. Advances in genetic testing have allowed for the identification of deleterious variants in patients with specific heart failure phenotypes (dilated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, and hypertrophic cardiomyopathy), and many of these have specific treatment implications. The diagnostic yield of genetic testing in heart failure is modest, and many rare variants are associated with incomplete penetrance and variable expressivity. Environmental factors and co-morbidities have a large role in the heterogeneity of the heart failure phenotype. Future endeavours should concentrate on the cumulative impact of genetic polymorphisms in the development of heart failure.
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Affiliation(s)
- Joshua Wong
- Baker Heart and Diabetes Institute and Department of Cardiometabolic Health, University of Melbourne, PO Box 6492, Melbourne, VIC 3004, Australia
| | - Stacey Peters
- Baker Heart and Diabetes Institute and Department of Cardiometabolic Health, University of Melbourne, PO Box 6492, Melbourne, VIC 3004, Australia
| | - Thomas H Marwick
- Baker Heart and Diabetes Institute and Department of Cardiometabolic Health, University of Melbourne, PO Box 6492, Melbourne, VIC 3004, Australia
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3
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Beltrami M, Fedele E, Fumagalli C, Mazzarotto F, Girolami F, Ferrantini C, Coppini R, Tofani L, Bertaccini B, Poggesi C, Olivotto I. Long-Term Prevalence of Systolic Dysfunction in MYBPC3 Versus MYH7-Related Hypertrophic Cardiomyopathy. CIRCULATION. GENOMIC AND PRECISION MEDICINE 2023; 16:363-371. [PMID: 37409452 DOI: 10.1161/circgen.122.003832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 05/30/2023] [Indexed: 07/07/2023]
Abstract
BACKGROUND The 2 sarcomere genes most commonly associated with hypertrophic cardiomyopathy (HCM), MYBPC3 (myosin-binding protein C3) and MYH7 (β-myosin heavy chain), are indistinguishable at presentation, and genotype-phenotype correlations have been elusive. Based on molecular and pathophysiological differences, however, it is plausible to hypothesize a different behavior in myocardial performance, impacting lifetime changes in left ventricular (LV) function. METHODS We reviewed the initial and final echocardiograms of 402 consecutive HCM patients with pathogenic or likely pathogenic MYBPC3 (n=251) or MYH7 (n=151) mutations, followed over 9±8 years. RESULTS At presentation, MYBPC3 patients were less frequently obstructive (15% versus 26%; P=0.005) and had lower LV ejection fraction compared with MYH7 (66±8% versus 68±8%, respectively; P=0.03). Both HCM patients harboring MYBPC3 and MYH7 mutations exhibited a small but significant decline in LV systolic function during follow-up; however, new onset of severe LV systolic dysfunction (LV ejection fraction, <50%) was greater among MYBPC3 patients (15% versus 5% among MYH7; P=0.013). Prevalence of grade II/III diastolic dysfunction at final evaluation was comparable between MYBPC3 and MYH7 patients (P=0.509). In a Cox multivariable analysis, MYBPC3-positive status (hazard ratio, 2.53 [95% CI, 1.09-5.82]; P=0.029), age (hazard ratio, 1.03 [95% CI, 1.00-1.06]; P=0.027), and atrial fibrillation (hazard ratio, 2.39 [95% CI, 1.14-5.05]; P=0.020) were independent predictors of severe systolic dysfunction. No statistically significant differences occurred with regard to incidence of atrial fibrillation, heart failure, appropriate implanted cardioverter defibrillator shock, or cardiovascular death. CONCLUSIONS MYBPC3-related HCM showed increased long-term prevalence of systolic dysfunction compared with MYH7, in spite of similar outcome. Such observations suggest different pathophysiology of clinical progression in the 2 subsets and may prove relevant for understanding of genotype-phenotype correlations in HCM.
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Affiliation(s)
- Matteo Beltrami
- Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (M.B., C.F.)
| | - Elisa Fedele
- Department of Cardiology, Policlinico Casilino, Rome, Italy (E.F.)
| | - Carlo Fumagalli
- Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (M.B., C.F.)
- Department of Advanced Medical and Surgical Sciences, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy (C.F.)
| | - Francesco Mazzarotto
- Department of Molecular and Translational Medicine, University of Brescia, Italy (F.M.)
| | | | - Cecilia Ferrantini
- Department of Experimental and Clinical Medicine (C.F., C.P., I.O.), University of Florence, Italy
| | - Raffaele Coppini
- Division of Pharmacology, Department of Neuroscience, Psychology, Drug Sciences and Child Health (NeuroFarBa) (R.C.), University of Florence, Italy
| | - Lorenzo Tofani
- Department of Statistics, Computer Science, Applications (L.T., B.B.), University of Florence, Italy
| | - Bruno Bertaccini
- Department of Statistics, Computer Science, Applications (L.T., B.B.), University of Florence, Italy
| | - Corrado Poggesi
- Department of Experimental and Clinical Medicine (C.F., C.P., I.O.), University of Florence, Italy
| | - Iacopo Olivotto
- Meyer Children's Hospital, IRCSS, Florence, Italy (F.G., I.O.)
- Department of Experimental and Clinical Medicine (C.F., C.P., I.O.), University of Florence, Italy
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4
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A Novel Loss-of-function Mutation in MYBPC3 Causes Familial Hypertrophic Cardiomyopathy with Extreme Intrafamilial Phenotypic Heterogeneity. Balkan J Med Genet 2022; 25:71-78. [PMID: 36880031 PMCID: PMC9985356 DOI: 10.2478/bjmg-2022-0002] [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: 03/04/2023] Open
Abstract
Cardiomyopathies are a heterogeneous group of diseases predominantly affecting the heart muscle and often lead to progressive heart failure-related disability or cardiovascular death. Hypertrophic cardiomyopathy (HCM) is a cardiac muscle disorder mostly caused by the mutations in genes encoding cardiac sarcomere. Germ-line mutations in MYBPC3 causes hypertrophic cardiomyopathy (HCM). However, most of the HCM associated MYBPC3 mutations were truncating mutations. Extreme phenotypic heterogeneity was observed among HCM patients with MYBPC3 mutations. In this study, we investigated a Chinese man who presented with HCM. Whole exome sequencing identified a novel heterozygous deletion (c.3781_3785delGAGGC) in exon 33 of the MYBPC3 in the proband. This heterozygous variant causes frameshift (p.Glu1261Thrfs*3), which predicted to form a truncated MYBPC3 protein. The proband's father also carries this variant in a heterozygous state while the proband's mother did not harbor this variant. Here, we report on a novel deletion in the MYBPC3 gene associated with HCM. We also highlight the importance of whole exome sequencing for molecular diagnosis for the patients with familial HCM.
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5
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Suay-Corredera C, Alegre-Cebollada J. The mechanics of the heart: zooming in on hypertrophic cardiomyopathy and cMyBP-C. FEBS Lett 2022; 596:703-746. [PMID: 35224729 DOI: 10.1002/1873-3468.14301] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 01/10/2022] [Accepted: 01/14/2022] [Indexed: 11/10/2022]
Abstract
Hypertrophic cardiomyopathy (HCM), a disease characterized by cardiac muscle hypertrophy and hypercontractility, is the most frequently inherited disorder of the heart. HCM is mainly caused by variants in genes encoding proteins of the sarcomere, the basic contractile unit of cardiomyocytes. The most frequently mutated among them is MYBPC3, which encodes cardiac myosin-binding protein C (cMyBP-C), a key regulator of sarcomere contraction. In this review, we summarize clinical and genetic aspects of HCM and provide updated information on the function of the healthy and HCM sarcomere, as well as on emerging therapeutic options targeting sarcomere mechanical activity. Building on what is known about cMyBP-C activity, we examine different pathogenicity drivers by which MYBPC3 variants can cause disease, focussing on protein haploinsufficiency as a common pathomechanism also in nontruncating variants. Finally, we discuss recent evidence correlating altered cMyBP-C mechanical properties with HCM development.
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6
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Enzan N, Matsushima S, Ide T, Kaku H, Tohyama T, Funakoshi K, Higo T, Tsutsui H. Sex Differences in Time-Dependent Changes in B-Type Natriuretic Peptide in Hypertrophic Cardiomyopathy. Circ Rep 2021; 3:594-603. [PMID: 34703937 PMCID: PMC8492405 DOI: 10.1253/circrep.cr-21-0110] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 08/11/2021] [Indexed: 11/24/2022] Open
Abstract
Background:
Female sex is reported to be associated with poor prognosis in hypertrophic cardiomyopathy (HCM). The plasma B-type natriuretic peptide (BNP) concentration is a prognostic predictor in HCM. However, the effect of sex on BNP concentrations remains unclear among HCM patients. Methods and Results:
Patient records in the Clinical Personal Records of HCM national database of the Japanese Ministry of Health, Labour and Welfare from 2009 to 2014 were analyzed. Of 3,570 HCM patients, 611 in whom BNP concentrations were assessed at both baseline and the 2-year follow-up were included in this analysis. The mean age was 60.4 years and 254 (41.6%) patients were female. Median (interquartile range) BNP concentrations were higher in females than males at both baseline (320.3 [159.0–583.1] vs. 182.8 [86.1–363.9] pg/mL; P<0.001) and the 2-year follow-up (299.2 [147.0–535.3] vs. 161.0 [76.2–310.0] pg/mL; P<0.001). Female sex was associated with higher natural log-transformed BNP at the 2-year follow-up regardless of clinical characteristics, including echocardiographic findings and BNP concentrations at baseline (coefficient 0.31; 95% confidence interval 0.13–0.48; P<0.001). Cubic spline analysis showed that, among patients with high BNP concentrations at baseline, females had higher BNP concentrations at the 2-year follow-up than males. Conclusions:
In HCM, female sex was associated with higher BNP concentrations than male sex, independent of clinical characteristics, including BNP concentrations at baseline.
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Affiliation(s)
- Nobuyuki Enzan
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, Kyushu University Fukuoka Japan
| | - Shouji Matsushima
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, Kyushu University Fukuoka Japan
| | - Tomomi Ide
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, Kyushu University Fukuoka Japan
| | - Hidetaka Kaku
- Department of Cardiology, Japan Community Healthcare Organization Kyushu Hospital Fukuoka Japan
| | - Takeshi Tohyama
- Center for Clinical and Translational Research, Kyushu University Hospital Fukuoka Japan
| | - Kouta Funakoshi
- Center for Clinical and Translational Research, Kyushu University Hospital Fukuoka Japan
| | - Taiki Higo
- Department of Cardiovascular Medicine, National Hospital Organization, Kyushu Medical Center Fukuoka Japan
| | - Hiroyuki Tsutsui
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, Kyushu University Fukuoka Japan
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7
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Yogasundaram H, Alhumaid W, Dzwiniel T, Christian S, Oudit GY. Cardiomyopathies and Genetic Testing in Heart Failure: Role in Defining Phenotype-Targeted Approaches and Management. Can J Cardiol 2021; 37:547-559. [PMID: 33493662 DOI: 10.1016/j.cjca.2021.01.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 01/11/2021] [Accepted: 01/12/2021] [Indexed: 12/29/2022] Open
Abstract
Cardiomyopathies represent an important cause of heart failure, often affecting young individuals, and have important implications for relatives. Genetic testing for cardiomyopathies is an established care pathway in contemporary cardiology practice. The primary cardiomyopathies where genetic testing is indicated are hypertrophic, dilated, arrhythmogenic, and restrictive cardiomyopathies, with left ventricular noncompaction as a variant phenotype. Early identification and initiation of therapies in patients with inherited cardiomyopathies allow for targeting asymptomatic and presymptomatic patients in stages A and B of the American College of Cardiology/American Heart Association classification of heart failure. The current approach for genetic testing uses gene panel-based testing with the ability to extend to whole-exome and whole-genome sequencing in rare instances. The central components of genetic testing include defining the genetic basis of the diagnosis, providing prognostic information, and the ability to screen and risk-stratify relatives. Genetic testing for cardiomyopathies should be coordinated by a multidisciplinary team including adult and pediatric cardiologists, genetic counsellors, and geneticists, with access to expertise in cardiac imaging and electrophysiology. A pragmatic approach for addressing genetic variants of uncertain significance is important. In this review, we highlight the indications for genetic testing in the various cardiomyopathies, the value of early diagnosis and treatment, family screening, and the care process involved in genetic counselling and testing.
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Affiliation(s)
- Haran Yogasundaram
- Department of Medicine, Division of Cardiology, University of Alberta, Edmonton, Alberta, Canada; Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Waleed Alhumaid
- Department of Medicine, Division of Cardiology, University of Alberta, Edmonton, Alberta, Canada; Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Tara Dzwiniel
- Department of Medical Genetics, University of Alberta, Edmonton, Alberta, Canada
| | - Susan Christian
- Department of Medical Genetics, University of Alberta, Edmonton, Alberta, Canada
| | - Gavin Y Oudit
- Department of Medicine, Division of Cardiology, University of Alberta, Edmonton, Alberta, Canada; Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada.
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8
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Arif M, Nabavizadeh P, Song T, Desai D, Singh R, Bazrafshan S, Kumar M, Wang Y, Gilbert RJ, Dhandapany PS, Becker RC, Kranias EG, Sadayappan S. Genetic, clinical, molecular, and pathogenic aspects of the South Asian-specific polymorphic MYBPC3 Δ25bp variant. Biophys Rev 2020; 12:1065-1084. [PMID: 32656747 PMCID: PMC7429610 DOI: 10.1007/s12551-020-00725-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 07/03/2020] [Indexed: 02/06/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is a cardiac genetic disease characterized by ventricular enlargement, diastolic dysfunction, and increased risk for sudden cardiac death. Sarcomeric genetic defects are the predominant known cause of HCM. In particular, mutations in the myosin-binding protein C gene (MYBPC3) are associated with ~ 40% of all HCM cases in which a genetic basis has been established. A decade ago, our group reported a 25-base pair deletion in intron 32 of MYBPC3 (MYBPC3Δ25bp) that is uniquely prevalent in South Asians and is associated with autosomal dominant cardiomyopathy. Although our studies suggest that this deletion results in left ventricular dysfunction, cardiomyopathies, and heart failure, the precise mechanism by which this variant predisposes to heart disease remains unclear. Increasingly appreciated, however, is the contribution of secondary risk factors, additional mutations, and lifestyle choices in augmenting or modifying the HCM phenotype in MYBPC3Δ25bp carriers. Therefore, the goal of this review article is to summarize the current research dedicated to understanding the molecular pathophysiology of HCM in South Asians with the MYBPC3Δ25bp variant. An emphasis is to review the latest techniques currently applied to explore the MYBPC3Δ25bp pathogenesis and to provide a foundation for developing new diagnostic strategies and advances in therapeutics.
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Affiliation(s)
- Mohammed Arif
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA.
| | - Pooneh Nabavizadeh
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Taejeong Song
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Darshini Desai
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Rohit Singh
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Sholeh Bazrafshan
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Mohit Kumar
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Yigang Wang
- Department of Pathology and Laboratory Medicine, University of Cincinnati, College of Medicine, Cincinnati, OH, 45267, USA
| | - Richard J Gilbert
- Research Service, Providence VA Medical Center, Providence, RI, 02908, USA
| | - Perundurai S Dhandapany
- Centre for Cardiovascular Biology and Disease, Institute for Stem Cell Biology and Regenerative Medicine (inStem), Bangalore, India
- The Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, USA
- Department of Medicine, Oregon Health and Science University, Portland, OR, USA
- Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, OR, USA
| | - Richard C Becker
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, 45267, USA
| | - Sakthivel Sadayappan
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, College of Medicine, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA
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9
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[Modern genetic counselling : Practical aspects exemplified by hypertrophic cardiomyopathy]. Internist (Berl) 2019; 59:790-798. [PMID: 29943241 DOI: 10.1007/s00108-018-0452-z] [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: 10/28/2022]
Abstract
Genetic counselling and subsequent molecular genetic testing should be performed in patients when an inherited monogenic form of heart disease is suspected. For the individual patient as well as for the (possibly asymptomatic) relatives, molecular diagnostics is important for an early diagnosis, (preventive) therapy and prognosis assessment. Using the example of hypertrophic cardiomyopathy (HCM), the most common monogenic form of structural heart disease, essential aspects of modern genetic counselling are elucidated. Specific examples of one case with a classical form of hypertrophic obstructive cardiomyopathy and one case of congenital HCM with Noonan's syndrome are discussed.
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10
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Popa-Fotea NM, Micheu MM, Bataila V, Scafa-Udriste A, Dorobantu L, Scarlatescu AI, Zamfir D, Stoian M, Onciul S, Dorobantu M. Exploring the Continuum of Hypertrophic Cardiomyopathy-From DNA to Clinical Expression. ACTA ACUST UNITED AC 2019; 55:medicina55060299. [PMID: 31234582 PMCID: PMC6630598 DOI: 10.3390/medicina55060299] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2019] [Revised: 06/20/2019] [Accepted: 06/20/2019] [Indexed: 12/29/2022]
Abstract
The concepts underlying hypertrophic cardiomyopathy (HCM) pathogenesis have evolved greatly over the last 60 years since the pioneering work of the British pathologist Donald Teare, presenting the autopsy findings of “asymmetric hypertrophy of the heart in young adults”. Advances in human genome analysis and cardiac imaging techniques have enriched our understanding of the complex architecture of the malady and shaped the way we perceive the illness continuum. Presently, HCM is acknowledged as “a disease of the sarcomere”, where the relationship between genotype and phenotype is not straightforward but subject to various genetic and nongenetic influences. The focus of this review is to discuss key aspects related to molecular mechanisms and imaging aspects that have prompted genotype–phenotype correlations, which will hopefully empower patient-tailored health interventions.
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Affiliation(s)
- Nicoleta Monica Popa-Fotea
- Department of Cardiology, Clinical Emergency Hospital of Bucharest, Floreasca Street 8, 014461 Bucharest, Romania.
| | - Miruna Mihaela Micheu
- Department of Cardiology, Clinical Emergency Hospital of Bucharest, Floreasca Street 8, 014461 Bucharest, Romania.
| | - Vlad Bataila
- Department of Cardiology, Clinical Emergency Hospital of Bucharest, Floreasca Street 8, 014461 Bucharest, Romania.
| | - Alexandru Scafa-Udriste
- Department of Cardiology, Clinical Emergency Hospital of Bucharest, Floreasca Street 8, 014461 Bucharest, Romania.
- Department 4-Cardiothoracic Pathology, University of Medicine and Pharmacy Carol Davila, Eroii Sanitari Bvd. 8, 050474 Bucharest, Romania.
| | - Lucian Dorobantu
- Cardiomyopathy Center, Monza Hospital, Tony Bulandra Street 27, 021968 Bucharest, Romania.
| | - Alina Ioana Scarlatescu
- Department of Cardiology, Clinical Emergency Hospital of Bucharest, Floreasca Street 8, 014461 Bucharest, Romania.
| | - Diana Zamfir
- Department of Cardiology, Clinical Emergency Hospital of Bucharest, Floreasca Street 8, 014461 Bucharest, Romania.
| | - Monica Stoian
- Department of Cardiology, Clinical Emergency Hospital of Bucharest, Floreasca Street 8, 014461 Bucharest, Romania.
| | - Sebastian Onciul
- Department of Cardiology, Clinical Emergency Hospital of Bucharest, Floreasca Street 8, 014461 Bucharest, Romania.
- Department 4-Cardiothoracic Pathology, University of Medicine and Pharmacy Carol Davila, Eroii Sanitari Bvd. 8, 050474 Bucharest, Romania.
| | - Maria Dorobantu
- Department of Cardiology, Clinical Emergency Hospital of Bucharest, Floreasca Street 8, 014461 Bucharest, Romania.
- Department 4-Cardiothoracic Pathology, University of Medicine and Pharmacy Carol Davila, Eroii Sanitari Bvd. 8, 050474 Bucharest, Romania.
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11
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Mathew J, Zahavich L, Lafreniere-Roula M, Wilson J, George K, Benson L, Bowdin S, Mital S. Utility of genetics for risk stratification in pediatric hypertrophic cardiomyopathy. Clin Genet 2017; 93:310-319. [DOI: 10.1111/cge.13157] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 09/17/2017] [Accepted: 09/27/2017] [Indexed: 12/29/2022]
Affiliation(s)
- J. Mathew
- Cardiology Department; The Royal Children’s Hospital; Melbourne Victoria Australia
| | - L. Zahavich
- Division of Cardiology, Department of Pediatrics; Hospital for Sick Children, University of Toronto; Toronto Ontario Canada
| | - M. Lafreniere-Roula
- Division of Cardiology, Department of Pediatrics; Hospital for Sick Children, University of Toronto; Toronto Ontario Canada
| | - J. Wilson
- Division of Cardiology, Department of Pediatrics; Hospital for Sick Children, University of Toronto; Toronto Ontario Canada
| | - K. George
- Division of Cardiology, Department of Pediatrics; Hospital for Sick Children, University of Toronto; Toronto Ontario Canada
| | - L. Benson
- Division of Cardiology, Department of Pediatrics; Hospital for Sick Children, University of Toronto; Toronto Ontario Canada
| | - S. Bowdin
- Division of Cardiology, Department of Pediatrics; Hospital for Sick Children, University of Toronto; Toronto Ontario Canada
| | - S. Mital
- Division of Cardiology, Department of Pediatrics; Hospital for Sick Children, University of Toronto; Toronto Ontario Canada
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12
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Viswanathan SK, Sanders HK, McNamara JW, Jagadeesan A, Jahangir A, Tajik AJ, Sadayappan S. Hypertrophic cardiomyopathy clinical phenotype is independent of gene mutation and mutation dosage. PLoS One 2017; 12:e0187948. [PMID: 29121657 PMCID: PMC5679632 DOI: 10.1371/journal.pone.0187948] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 10/27/2017] [Indexed: 12/27/2022] Open
Abstract
Over 1,500 gene mutations are known to cause hypertrophic cardiomyopathy (HCM). Previous studies suggest that cardiac β-myosin heavy chain (MYH7) gene mutations are commonly associated with a more severe phenotype, compared to cardiac myosin binding protein-C (MYBPC3) gene mutations with milder phenotype, incomplete penetrance and later age of onset. Compound mutations can worsen the phenotype. This study aimed to validate these comparative differences in a large cohort of individuals and families with HCM. We performed genome-phenome correlation among 80 symptomatic HCM patients, 35 asymptomatic carriers and 35 non-carriers, using an 18-gene clinical diagnostic HCM panel. A total of 125 mutations were identified in 14 genes. MYBPC3 and MYH7 mutations contributed to 50.0% and 24.4% of the HCM patients, respectively, suggesting that MYBPC3 mutations were the most frequent cause of HCM in our cohort. Double mutations were found in only nine HCM patients (7.8%) who were phenotypically indistinguishable from single-mutation carriers. Comparisons of clinical parameters of MYBPC3 and MYH7 mutants were not statistically significant, but asymptomatic carriers had high left ventricular ejection fraction and diastolic dysfunction when compared to non-carriers. The presence of double mutations increases the risk for symptomatic HCM with no change in severity, as determined in this study subset. The pathologic effects of MYBPC3 and MYH7 were found to be independent of gene mutation location. Furthermore, HCM pathology is independent of protein domain disruption in both MYBPC3 and MYH7. These data provide evidence that MYBPC3 mutations constitute the preeminent cause of HCM and that they are phenotypically indistinguishable from HCM caused by MYH7 mutations.
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Affiliation(s)
- Shiv Kumar Viswanathan
- Heart Lung Vascular Institute, Division of Cardiology, Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio, United States of America
- Department of Cell and Molecular Physiology, Center for Translational Research and Education, Health Sciences Division, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Heather K. Sanders
- Aurora Cardiovascular Services, St. Luke’s Medical Center, Milwaukee, Wisconsin, United States of America
- Center for Integrative Research on Cardiovascular Aging (CIRCA), Aurora Health Care, Milwaukee, Wisconsin, United States of America
| | - James W. McNamara
- Heart Lung Vascular Institute, Division of Cardiology, Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio, United States of America
- Department of Cell and Molecular Physiology, Center for Translational Research and Education, Health Sciences Division, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Aravindakshan Jagadeesan
- Department of Cell and Molecular Physiology, Center for Translational Research and Education, Health Sciences Division, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Arshad Jahangir
- Aurora Cardiovascular Services, St. Luke’s Medical Center, Milwaukee, Wisconsin, United States of America
- Center for Integrative Research on Cardiovascular Aging (CIRCA), Aurora Health Care, Milwaukee, Wisconsin, United States of America
| | - A. Jamil Tajik
- Aurora Cardiovascular Services, St. Luke’s Medical Center, Milwaukee, Wisconsin, United States of America
- Center for Integrative Research on Cardiovascular Aging (CIRCA), Aurora Health Care, Milwaukee, Wisconsin, United States of America
| | - Sakthivel Sadayappan
- Heart Lung Vascular Institute, Division of Cardiology, Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio, United States of America
- Department of Cell and Molecular Physiology, Center for Translational Research and Education, Health Sciences Division, Loyola University Chicago, Maywood, Illinois, United States of America
- * E-mail:
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13
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Significance of intronic and synonymous MYBPC3 gene variations in hypertrophic cardiomyopathy. GENE REPORTS 2017. [DOI: 10.1016/j.genrep.2017.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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14
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Weissler-Snir A, Hindieh W, Gruner C, Fourey D, Appelbaum E, Rowin E, Care M, Lesser JR, Haas TS, Udelson JE, Manning WJ, Olivotto I, Tomberli B, Maron BJ, Maron MS, Crean AM, Rakowski H, Chan RH. Lack of Phenotypic Differences by Cardiovascular Magnetic Resonance Imaging in MYH7 (β-Myosin Heavy Chain)- Versus MYBPC3 (Myosin-Binding Protein C)-Related Hypertrophic Cardiomyopathy. Circ Cardiovasc Imaging 2017; 10:CIRCIMAGING.116.005311. [PMID: 28193612 DOI: 10.1161/circimaging.116.005311] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 12/19/2016] [Indexed: 01/11/2023]
Abstract
BACKGROUND The 2 most commonly affected genes in hypertrophic cardiomyopathy (HCM) are MYH7 (β-myosin heavy chain) and MYBPC3 (β-myosin-binding protein C). Phenotypic differences between patients with mutations in these 2 genes have been inconsistent. Scarce data exist on the genotype-phenotype association as assessed by tomographic imaging using cardiac magnetic resonance imaging. METHODS AND RESULTS Cardiac magnetic resonance imaging was performed on 358 consecutive genotyped hypertrophic cardiomyopathy probands at 5 tertiary hypertrophic cardiomyopathy centers. Genetic testing revealed a pathogenic mutation in 159 patients (44.4%). The most common genes identified were MYH7 (n=53) and MYBPC3 (n=75); 33.1% and 47% of genopositive patients, respectively. Phenotypic characteristics by cardiac magnetic resonance imaging of these 2 groups were similar, including left ventricular volumes, mass, maximal wall thickness, morphology, left atrial volume, and mitral valve leaflet lengths (all P=non-significant). The presence of late gadolinium enhancement (65% versus 64%; P=0.99) and the proportion of total left ventricular mass (%late gadolinium enhancement; 10.4±13.2% versus 8.5±8.5%; P=0.44) were also similar. CONCLUSIONS This multicenter multinational study shows lack of phenotypic differences between MYH7- and MYBPC3-associated hypertrophic cardiomyopathy when assessed by cardiac magnetic resonance imaging. Postmutational mechanisms appear more relevant to thick-filament disease expression and outcome than the disease-causing variant per se.
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MESH Headings
- Adult
- Canada
- Cardiac Myosins/genetics
- Cardiomyopathy, Hypertrophic, Familial/diagnostic imaging
- Cardiomyopathy, Hypertrophic, Familial/genetics
- Cardiomyopathy, Hypertrophic, Familial/physiopathology
- Carrier Proteins/genetics
- Contrast Media/administration & dosage
- Europe
- Female
- Gadolinium DTPA/administration & dosage
- Genetic Association Studies
- Genetic Predisposition to Disease
- Humans
- Image Interpretation, Computer-Assisted
- Imaging, Three-Dimensional
- Magnetic Resonance Imaging, Cine
- Male
- Middle Aged
- Mutation
- Myosin Heavy Chains/genetics
- Phenotype
- Predictive Value of Tests
- Registries
- Risk Factors
- Stroke Volume
- Tertiary Care Centers
- United States
- Ventricular Function, Left
- Ventricular Remodeling
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Affiliation(s)
- Adaya Weissler-Snir
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Waseem Hindieh
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Christiane Gruner
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Dana Fourey
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Evan Appelbaum
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Ethan Rowin
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Melanie Care
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - John R Lesser
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Tammy S Haas
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - James E Udelson
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Warren J Manning
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Iacopo Olivotto
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Benedetta Tomberli
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Barry J Maron
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Martin S Maron
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Andrew M Crean
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Harry Rakowski
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.)
| | - Raymond H Chan
- From the Division of Cardiology (A.W.-S., W.H., C.G., D.F., M.C., A.M.C., H.R., R.H.C.) and Joint Department of Medical Imaging (A.M.C.), University Health Network, Toronto, Ontario, Canada; Division of Cardiology, Cardiovascular Center, University Hospital Zurich, Switzerland (C.G.); Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (E.A., W.J.M., R.H.C.); Hypertrophic Cardiomyopathy Center, Tufts Medical Center, Boston, MA (E.R., J.E.U., B.J.M., M.S.M.); The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, MN (J.R.L., T.S.H.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O., B.T.).
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15
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Abstract
Heart failure is highly influenced by heritability, and nearly 100 genes link to familial cardiomyopathy. Despite the marked genetic diversity that underlies these complex cardiovascular phenotypes, several key genes and pathways have emerged. Hypertrophic cardiomyopathy is characterized by increased contractility and a greater energetic cost of cardiac output. Dilated cardiomyopathy is often triggered by mutations that disrupt the giant protein titin. The energetic consequences of these mutations offer molecular targets and opportunities for new drug development and gene correction therapies.
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Affiliation(s)
- Elizabeth M McNally
- Center for Genetic Medicine, Northwestern University, Chicago, IL 60611, USA.
| | - David Y Barefield
- Center for Genetic Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Megan J Puckelwartz
- Center for Genetic Medicine, Northwestern University, Chicago, IL 60611, USA
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16
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Friedrich FW, Reischmann S, Schwalm A, Unger A, Ramanujam D, Münch J, Müller OJ, Hengstenberg C, Galve E, Charron P, Linke WA, Engelhardt S, Patten M, Richard P, van der Velden J, Eschenhagen T, Isnard R, Carrier L. FHL2 expression and variants in hypertrophic cardiomyopathy. Basic Res Cardiol 2014; 109:451. [PMID: 25358972 PMCID: PMC4215105 DOI: 10.1007/s00395-014-0451-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 10/04/2014] [Accepted: 10/22/2014] [Indexed: 11/28/2022]
Abstract
Based on evidence that FHL2 (four and a half LIM domains protein 2) negatively regulates cardiac hypertrophy we tested whether FHL2 altered expression or variants could be associated with hypertrophic cardiomyopathy (HCM). HCM is a myocardial disease characterized by left ventricular hypertrophy, diastolic dysfunction and increased interstitial fibrosis and is mainly caused by mutations in genes coding for sarcomeric proteins. FHL2 mRNA level, FHL2 protein level and I-band-binding density were lower in HCM patients than control individuals. Screening of 121 HCM patients without mutations in established disease genes identified 2 novel (T171M, V187L) and 4 known (R177Q, N226N, D268D, P273P) FHL2 variants in unrelated HCM families. We assessed the structural and functional consequences of the nonsynonymous substitutions after adeno-associated viral-mediated gene transfer in cardiac myocytes and in 3D-engineered heart tissue (EHT). Overexpression of FHL2 wild type or nonsynonymous substitutions in cardiac myocytes markedly down-regulated α-skeletal actin and partially blunted hypertrophy induced by phenylephrine or endothelin-1. After gene transfer in EHTs, force and velocity of both contraction and relaxation were higher with T171M and V187L FHL2 variants than wild type under basal conditions. Finally, chronic phenylephrine stimulation depressed EHT function in all groups, but to a lower extent in T171M-transduced EHTs. These data suggest that (1) FHL2 is down-regulated in HCM, (2) both FHL2 wild type and variants partially protected phenylephrine- or endothelin-1-induced hypertrophy in cardiac myocytes, and (3) FHL2 T171M and V187L nonsynonymous variants induced altered EHT contractility. These findings provide evidence that the 2 novel FHL2 variants could increase cardiac function in HCM.
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Affiliation(s)
- Felix W. Friedrich
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Silke Reischmann
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Aileen Schwalm
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Andreas Unger
- Department of Cardiovascular Physiology, Ruhr University Bochum, Bochum, Germany
| | - Deepak Ramanujam
- Institute of Pharmacology and Toxicology, Technical University Munich, Munich, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Munich, Munich, Germany
| | - Julia Münch
- University Heart Center Hamburg, Hamburg, Germany
| | - Oliver J. Müller
- Department of Cardiology, Internal Medicine III, University Hospital Heidelberg, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, Heidelberg, Germany
| | - Christian Hengstenberg
- Present Address: German Heart Centre of the Technical University Munich, Munich, Germany
- Klinik und Poliklinik für Innere Medizin II, Universitätsklinikum Regensburg, Regensburg, Germany
| | - Enrique Galve
- Unitat d’Insuficiència Cardiaca, Servei de Cardiologia, Hospital Vall d’Hebron, Barcelona, Spain
| | - Philippe Charron
- Inserm, U956, Paris, France
- ICAN Institute, UPMC Univ Paris 06, Paris, France
| | - Wolfgang A. Linke
- Department of Cardiovascular Physiology, Ruhr University Bochum, Bochum, Germany
| | - Stefan Engelhardt
- Institute of Pharmacology and Toxicology, Technical University Munich, Munich, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Munich, Munich, Germany
| | | | - Pascale Richard
- Inserm, U956, Paris, France
- ICAN Institute, UPMC Univ Paris 06, Paris, France
- Groupe Hospitalier Pitié-Salpêtrière, AP-HP Centre de référence des maladies cardiaques héréditaires, Paris, France
- Groupe Hospitalier Pitié-Salpêtrière, AP-HP,UF Cardiogénétique et Myogénétique, Paris, France
| | - Jolanda van der Velden
- Laboratory for Physiology, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Thomas Eschenhagen
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Richard Isnard
- Inserm, U956, Paris, France
- ICAN Institute, UPMC Univ Paris 06, Paris, France
- Groupe Hospitalier Pitié-Salpêtrière, AP-HP Centre de référence des maladies cardiaques héréditaires, Paris, France
| | - Lucie Carrier
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
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17
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Lopes LR, Syrris P, Guttmann OP, O'Mahony C, Tang HC, Dalageorgou C, Jenkins S, Hubank M, Monserrat L, McKenna WJ, Plagnol V, Elliott PM. Novel genotype-phenotype associations demonstrated by high-throughput sequencing in patients with hypertrophic cardiomyopathy. Heart 2014; 101:294-301. [PMID: 25351510 PMCID: PMC4345808 DOI: 10.1136/heartjnl-2014-306387] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Objective A predictable relation between genotype and disease expression is needed in order to use genetic testing for clinical decision-making in hypertrophic cardiomyopathy (HCM). The primary aims of this study were to examine the phenotypes associated with sarcomere protein (SP) gene mutations and test the hypothesis that variation in non-sarcomere genes modifies the phenotype. Methods Unrelated and consecutive patients were clinically evaluated and prospectively followed in a specialist clinic. High-throughput sequencing was used to analyse 41 genes implicated in inherited cardiac conditions. Variants in SP and non-SP genes were tested for associations with phenotype and survival. Results 874 patients (49.6±15.4 years, 67.8% men) were studied; likely disease-causing SP gene variants were detected in 383 (43.8%). Patients with SP variants were characterised by younger age and higher prevalence of family history of HCM, family history of sudden cardiac death, asymmetric septal hypertrophy, greater maximum LV wall thickness (all p values<0.0005) and an increased incidence of cardiovascular death (p=0.012). Similar associations were observed for individual SP genes. Patients with ANK2 variants had greater maximum wall thickness (p=0.0005). Associations at a lower level of significance were demonstrated with variation in other non-SP genes. Conclusions Patients with HCM caused by rare SP variants differ with respect to age at presentation, family history of the disease, morphology and survival from patients without SP variants. Novel associations for SP genes are reported and, for the first time, we demonstrate possible influence of variation in non-SP genes associated with other forms of cardiomyopathy and arrhythmia syndromes on the clinical phenotype of HCM.
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Affiliation(s)
- Luis R Lopes
- UCL Institute of Cardiovascular Science, London, UK
| | | | | | - Constantinos O'Mahony
- UCL Institute of Cardiovascular Science, London, UK The London Chest Hospital, London, UK
| | - Hak Chiaw Tang
- UCL Institute of Cardiovascular Science, London, UK National Heart Centre, Singapore, Singapore
| | | | | | - Mike Hubank
- UCL Genomics, Department of Molecular Haematology and Cancer Biology, UCL Institute of Child Health, London, UK
| | - Lorenzo Monserrat
- Instituto de Investigación Biomédica de la Universidad de A Coruña (INIBIC), Complexo Hospitalario Universitario de A Coruña (CHUAC)-Universidad de A Coruña, A Coruña, Spain
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18
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Abstract
Hypertrophic cardiomyopathy is a common inherited heart muscle disorder associated with sudden cardiac death, arrhythmias and heart failure. Genetic mutations can be identified in approximately 60% of patients; these are commonest in genes that encode proteins of the cardiac sarcomere. Similar to other Mendelian diseases these mutations are characterized by incomplete penetrance and variable clinical expression. Our knowledge of this genetic diversity is rapidly evolving as high-throughput DNA sequencing technology is now used to characterize an individual patient's disease. In addition, the genomic basis of several multisystem diseases associated with a hypertrophic cardiomyopathy phenotype has been elucidated. Genetic biomarkers can be helpful in making an accurate diagnosis and in identifying relatives at risk of developing the condition. In the clinical setting, genetic testing and genetic screening should be used pragmatically with appropriate counseling. Here we review the current role of genetic biomarkers in hypertrophic cardiomyopathy, highlight recent progress in the field and discuss future challenges.
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Affiliation(s)
- Caroline J Coats
- The Heart Hospital, 16-18 Westmoreland Street, London, W1G 8PH, UK
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19
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Charron P, Komajda M. Molecular genetics in hypertrophic cardiomyopathy: towards individualized management of the disease. Expert Rev Mol Diagn 2014; 6:65-78. [PMID: 16359268 DOI: 10.1586/14737159.6.1.65] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Hypertrophic cardiomyopathy is a relatively common genetic disease, affecting one person per 500 in the general population, and is clinically defined by the presence of unexplained left ventricular hypertrophy. Although recognized as the most common cause of sudden death in the young (especially in athletes), the cardiac expression of the disease is highly variable with respect to age at onset, degree of symptoms and risk of cardiac death. As a consequence, therapeutic strategies are diverse and must be adapted to the specific features of an individual. Recently, the molecular bases of the disease have been unraveled with the identification of a large number of mutations in genes encoding sarcomeric proteins. This review focuses on the impact of the molecular data on the understanding of the disease, and considers the emerging issues regarding the impact of molecular testing on the management of patients (or relatives) in clinical practice.
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Affiliation(s)
- Philippe Charron
- Centre of Reference for Cardiac Hereditary Diseases, Département de Génétique, Hôpital Pitié-Salpêtrière, 47 Boulevard de l'Hôpital, 75013 Paris, France.
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20
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Fraysse B, Weinberger F, Bardswell SC, Cuello F, Vignier N, Geertz B, Starbatty J, Krämer E, Coirault C, Eschenhagen T, Kentish JC, Avkiran M, Carrier L. Increased myofilament Ca2+ sensitivity and diastolic dysfunction as early consequences of Mybpc3 mutation in heterozygous knock-in mice. J Mol Cell Cardiol 2012; 52:1299-307. [PMID: 22465693 PMCID: PMC3370652 DOI: 10.1016/j.yjmcc.2012.03.009] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 03/06/2012] [Accepted: 03/09/2012] [Indexed: 01/10/2023]
Abstract
Hypertrophic cardiomyopathy (HCM) is frequently caused by mutations in MYBPC3 encoding cardiac myosin-binding protein C (cMyBP-C). The mechanisms leading from gene mutations to the HCM phenotype remain incompletely understood, partially because current mouse models of HCM do not faithfully reflect the human situation and early hypertrophy confounds the interpretation of functional alterations. The goal of this study was to evaluate whether myofilament Ca(2+) sensitization and diastolic dysfunction are associated or precede the development of left ventricular hypertrophy (LVH) in HCM. We evaluated the function of skinned and intact cardiac myocytes, as well as the intact heart in a recently developed Mybpc3-targeted knock-in mouse model carrying a point mutation frequently associated with HCM. Compared to wild-type, 10-week old homozygous knock-in mice exhibited i) higher myofilament Ca(2+) sensitivity in skinned ventricular trabeculae, ii) lower diastolic sarcomere length, and faster Ca(2+) transient decay in intact myocytes, and iii) LVH, reduced fractional shortening, lower E/A and E'/A', and higher E/E' ratios by echocardiography and Doppler analysis, suggesting systolic and diastolic dysfunction. In contrast, heterozygous knock-in mice, which mimic the human HCM situation, did not exhibit LVH or systolic dysfunction, but exhibited higher myofilament Ca(2+) sensitivity, faster Ca(2+) transient decay, and diastolic dysfunction. These data demonstrate that myofilament Ca(2+) sensitization and diastolic dysfunction are early phenotypic consequences of Mybpc3 mutations independent of LVH. The accelerated Ca(2+) transients point to compensatory mechanisms directed towards normalization of relaxation. We propose that HCM is a model for diastolic heart failure and this mouse model could be valuable in studying mechanisms and treatment modalities.
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Key Words
- cmybp-c, cardiac myosin-binding protein c
- ctni, cardiac troponin i
- csq, calsequestrin
- hcm, hypertrophic cardiomyopathy
- het, heterozygous mybpc3-targeted knock-in mice
- ki, homozygous mybpc3-targeted knock-in mice
- ko, homozygous mybpc3-targeted knock-out mice
- lvh, left ventricular hypertrophy
- max f, maximal ca2+-activated force
- mybpc3, human cardiac myosin-binding protein c gene
- mybpc3, mouse cardiac myosin-binding protein c gene
- ncx, na+/ca2+ exchanger
- nh, hill coefficient
- pca50, log of [ca2+] required for 50% of maximal activation
- pka, camp-dependent protein kinase a
- plb, phospholamban
- serca2, sr-ca2+ atpase
- sl, sarcomere length
- sr, sarcoplasmic reticulum
- ca2+ sensitivity
- ca2+ transient
- diastolic dysfunction
- hypertrophy
- mouse model
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Affiliation(s)
- Bodvaël Fraysse
- Inserm, U974, Institut de Myologie, Paris, F-75013, France
- Université Pierre et Marie Curie-Paris6, UMR-S974, CNRS, UMR7215, Institut de Myologie, IFR14, Paris, F-75013, France
| | - Florian Weinberger
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sonya C. Bardswell
- King's College London British Heart Foundation Centre, Cardiovascular Division, St. Thomas' Hospital, London SE1 7EH, UK
| | - Friederike Cuello
- King's College London British Heart Foundation Centre, Cardiovascular Division, St. Thomas' Hospital, London SE1 7EH, UK
| | - Nicolas Vignier
- Inserm, U974, Institut de Myologie, Paris, F-75013, France
- Université Pierre et Marie Curie-Paris6, UMR-S974, CNRS, UMR7215, Institut de Myologie, IFR14, Paris, F-75013, France
| | - Birgit Geertz
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jutta Starbatty
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Elisabeth Krämer
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Catherine Coirault
- Inserm, U974, Institut de Myologie, Paris, F-75013, France
- Université Pierre et Marie Curie-Paris6, UMR-S974, CNRS, UMR7215, Institut de Myologie, IFR14, Paris, F-75013, France
| | - Thomas Eschenhagen
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jonathan C. Kentish
- King's College London British Heart Foundation Centre, Cardiovascular Division, St. Thomas' Hospital, London SE1 7EH, UK
| | - Metin Avkiran
- King's College London British Heart Foundation Centre, Cardiovascular Division, St. Thomas' Hospital, London SE1 7EH, UK
| | - Lucie Carrier
- Inserm, U974, Institut de Myologie, Paris, F-75013, France
- Université Pierre et Marie Curie-Paris6, UMR-S974, CNRS, UMR7215, Institut de Myologie, IFR14, Paris, F-75013, France
- Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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21
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Bai F, Weis A, Takeda AK, Chase PB, Kawai M. Enhanced active cross-bridges during diastole: molecular pathogenesis of tropomyosin's HCM mutations. Biophys J 2011; 100:1014-23. [PMID: 21320446 DOI: 10.1016/j.bpj.2011.01.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 12/22/2010] [Accepted: 01/03/2011] [Indexed: 11/28/2022] Open
Abstract
Three HCM-causing tropomyosin (Tm) mutants (V95A, D175N, and E180G) were examined using the thin-filament extraction and reconstitution technique. The effects of Ca(2+), ATP, phosphate, and ADP concentrations on cross-bridge kinetics in myocardium reconstituted with each of these mutants were studied at 25°C, and compared to wild-type (WT) Tm at physiological ionic strength (200 mM). All three mutants showed significantly higher (2-3.5 fold) low Ca(2+) tension (T(LC)) and stiffness than WT at pCa 8.0. High Ca(2+) tension (T(HC)) was significantly higher for E180G than that for WT, whereas T(HC) of V95A and D175N was similar to WT; high Ca(2+) stiffness (Y(HC)) had the same trend. The Ca(2+) sensitivity of isometric force was significantly greater for V95A and E180G than for WT, whereas that of D175N remained the same as for WT; for all mutants, cooperativity was lower than for WT. Nine kinetic constants and the cross-bridge distribution were deduced using sinusoidal analysis. The number of force-generating cross bridges was similar among the D175N, E180G, and WT Tm forms, but it was significantly larger in the case of V95A than WT. We conclude that the increased number of actively cycling cross bridges at pCa 8 is the major cause of Tm mutation-related HCM pathogenesis, which may result in diastolic dysfunction. Decreased contractility (T(act)) in V95A and D175N may further contribute to the severity of myocyte hypertrophy and related prognosis of the disease.
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Affiliation(s)
- Fan Bai
- Department of Anatomy and Cell Biology, University of Iowa, Iowa City, Iowa, USA
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22
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Kim L, Devereux RB, Basson CT. Impact of genetic insights into mendelian disease on cardiovascular clinical practice. Circulation 2011; 123:544-50. [PMID: 21300962 DOI: 10.1161/circulationaha.109.914804] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Luke Kim
- Greenberg Division of Cardiology, Weill Medical College of Cornell University, New York Presbyterian Hospital–Cornell Medical Center, New York, NY, USA
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23
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Fowler SJ, Bloise R. Genetic Testing for Cardiac Arrhythmias: Ready for Prime Time? Card Electrophysiol Clin 2010; 2:611-621. [PMID: 28770723 DOI: 10.1016/j.ccep.2010.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Despite the heterogeneity of substrates and clinical expressivity, genetic testing has a direct impact on clinical practice: it allows a specific diagnosis, including silent carriers (ie, asymptomatic diagnosis) and, in select diseases, the identification of a mutation has major impact for risk stratification and treatment of patients. This article addresses the role of genetic testing for each of the most epidemiologically relevant inherited arrhythmogenic diseases, specifically long QT syndrome, Brugada syndrome, catecholaminergic polymorphic ventricular tachycardia, hypertrophic cardiomyopathy, and arrhythmogenic right ventricular cardiomyopathy.
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Affiliation(s)
- Steven J Fowler
- Cardiovascular Genetics Program, Leon H. Charney Division of Cardiology, NYU Langone Medical Center, New York, USA; Clinical Cardiac Electrophysiology, Leon H. Charney Division of Cardiology, NYU Langone Medical Center, New York, USA
| | - Raffaella Bloise
- Molecular Cardiology, IRCCS Fondazione Salvatore Maugeri, Pavia, Italy; Department of Cardiology, University of Pavia, Pavia, Italy
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24
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Richard P, Fressart V, Charron P, Hainque B. Génétique des cardiomyopathies héréditaires. ACTA ACUST UNITED AC 2010; 58:343-52. [DOI: 10.1016/j.patbio.2009.10.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Accepted: 10/16/2009] [Indexed: 11/30/2022]
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25
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Force T, Bonow RO, Houser SR, Solaro RJ, Hershberger RE, Adhikari B, Anderson ME, Boineau R, Byrne BJ, Cappola TP, Kalluri R, LeWinter MM, Maron MS, Molkentin JD, Ommen SR, Regnier M, Tang WHW, Tian R, Konstam MA, Maron BJ, Seidman CE. Research priorities in hypertrophic cardiomyopathy: report of a Working Group of the National Heart, Lung, and Blood Institute. Circulation 2010; 122:1130-3. [PMID: 20837938 DOI: 10.1161/circulationaha.110.950089] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Thomas Force
- Center for Translational Medicine and Cardiology Division, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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26
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Xu Q, Dewey S, Nguyen S, Gomes AV. Malignant and benign mutations in familial cardiomyopathies: Insights into mutations linked to complex cardiovascular phenotypes. J Mol Cell Cardiol 2010; 48:899-909. [DOI: 10.1016/j.yjmcc.2010.03.005] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2009] [Revised: 03/01/2010] [Accepted: 03/06/2010] [Indexed: 12/17/2022]
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27
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Callis TE, Jensen BC, Weck KE, Willis MS. Evolving molecular diagnostics for familial cardiomyopathies: at the heart of it all. Expert Rev Mol Diagn 2010; 10:329-51. [PMID: 20370590 PMCID: PMC5022563 DOI: 10.1586/erm.10.13] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cardiomyopathies are an important and heterogeneous group of common cardiac diseases. An increasing number of cardiomyopathies are now recognized to have familial forms, which result from single-gene mutations that render a Mendelian inheritance pattern, including hypertrophic cardiomyopathy, dilated cardiomyopathy, restrictive cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy and left ventricular noncompaction cardiomyopathy. Recently, clinical genetic tests for familial cardiomyopathies have become available for clinicians evaluating and treating patients with these diseases, making it necessary to understand the current progress and challenges in cardiomyopathy genetics and diagnostics. In this review, we summarize the genetic basis of selected cardiomyopathies, describe the clinical utility of genetic testing for cardiomyopathies and outline the current challenges and emerging developments.
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Affiliation(s)
- Thomas E Callis
- PGxHealth Division, Clinical Data, Inc., 5 Science Park, New Haven, CT 06511, USA
| | - Brian C Jensen
- McAllister Heart Institute, University of North Carolina, Chapel Hill, NC, 27599-7126, USA and Department of Internal Medicine, Section of Cardiology, University of North Carolina, Chapel Hill, NC 27599-7075, USA
| | - Karen E Weck
- Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, NC 27599-7525, USA
| | - Monte S Willis
- Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, NC 27599-7525, USA and McAllister Heart Institute, University of North Carolina at Chapel Hill, 2340B Medical Biomolecular Research Building, 103 Mason Farm Road, Chapel Hill, NC 27599-7525, USA Tel.: +1 919 843 1938 Fax: +1 919 843 4585
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28
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Christiaans I, van Engelen K, van Langen IM, Birnie E, Bonsel GJ, Elliott PM, Wilde AAM. Risk stratification for sudden cardiac death in hypertrophic cardiomyopathy: systematic review of clinical risk markers. Europace 2010; 12:313-21. [PMID: 20118111 DOI: 10.1093/europace/eup431] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
We performed a systematic literature review of recommended 'major' and 'possible' clinical risk markers for sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM). We searched the Medline, Embase and Cochrane databases for articles published between 1971 and 2007. We included English language reports on HCM patients containing follow-up data on the endpoint (sudden) cardiac death using survival analysis. Analysis was undertaken using the quality of reporting of meta-analyses (QUORUM) statement checklist. The quality was checked using a quality assessment form from the Cochrane Collaboration. Thirty studies met inclusion criteria and passed quality assessment. The use of the six major risk factors (previous cardiac arrest or sustained ventricular tachycardia, non-sustained ventricular tachycardia, extreme left ventricular hypertrophy, unexplained syncope, abnormal blood pressure response, and family history of sudden death) in risk stratification for SCD as recommended by international guidelines was supported by the literature. In addition, left ventricular outflow tract obstruction seems associated with a higher risk of SCD. Our systematic review provides sound evidence for the use of the six major risk factors for SCD in the risk stratification of HCM patients. Left ventricular outflow tract obstruction could be included in the overall risk profile of patients with a marked left ventricular outflow gradient under basal conditions.
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Affiliation(s)
- Imke Christiaans
- Department of Clinical Genetics, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
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29
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Fowler SJ, Napolitano C, Priori SG. The genetics of cardiomyopathy: Genotyping and genetic counseling. CURRENT TREATMENT OPTIONS IN CARDIOVASCULAR MEDICINE 2009; 11:433-46. [DOI: 10.1007/s11936-009-0046-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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30
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Ventricular fibrillation in MYH7-related hypertrophic cardiomyopathy before onset of ventricular hypertrophy. Heart Rhythm 2009; 6:1366-9. [DOI: 10.1016/j.hrthm.2009.04.029] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2009] [Accepted: 04/21/2009] [Indexed: 11/23/2022]
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31
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Bos JM, Towbin JA, Ackerman MJ. Diagnostic, prognostic, and therapeutic implications of genetic testing for hypertrophic cardiomyopathy. J Am Coll Cardiol 2009; 54:201-11. [PMID: 19589432 DOI: 10.1016/j.jacc.2009.02.075] [Citation(s) in RCA: 237] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2008] [Revised: 02/20/2009] [Accepted: 02/24/2009] [Indexed: 02/05/2023]
Abstract
Over the last 2 decades, the pathogenic basis for the most common heritable cardiovascular disease, hypertrophic cardiomyopathy (HCM), has been investigated extensively. Affecting approximately 1 in 500 individuals, HCM is the most common cause of sudden death in young athletes. In recent years, genomic medicine has been moving from the bench to the bedside throughout all medical disciplines including cardiology. Now, genomic medicine has entered clinical practice as it pertains to the evaluation and management of patients with HCM. The continuous research and discoveries of new HCM susceptibility genes, the growing amount of data from genotype-phenotype correlation studies, and the introduction of commercially available genetic tests for HCM make it essential that the modern-day cardiologist understand the diagnostic, prognostic, and therapeutic implications of HCM genetic testing.
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Affiliation(s)
- J Martijn Bos
- Mayo Clinic Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota 55905, USA
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32
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Carrier L, Schlossarek S, Willis MS, Eschenhagen T. The ubiquitin-proteasome system and nonsense-mediated mRNA decay in hypertrophic cardiomyopathy. Cardiovasc Res 2009; 85:330-8. [PMID: 19617224 DOI: 10.1093/cvr/cvp247] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Cardiomyopathies represent an important cause of cardiovascular morbidity and mortality due to heart failure, arrhythmias, and sudden death. Most forms of hypertrophic cardiomyopathy (HCM) are familial with an autosomal-dominant mode of inheritance. Over the last 20 years, the genetic basis of the disease has been largely unravelled. HCM is considered as a sarcomeropathy involving mutations in sarcomeric proteins, most often beta-myosin heavy chain and cardiac myosin-binding protein C. 'Missense' mutations, more common in the former, are associated with dysfunctional proteins stably integrated into the sarcomere. 'Nonsense' and frameshift mutations, more common in the latter, are associated with low mRNA and protein levels derived from the diseased allele, leading to haploinsufficiency of the remaining healthy allele. The two quality control systems responsible for the removal of the affected mRNAs and proteins are the nonsense-mediated mRNA decay (NMD) and the ubiquitin-proteasome system (UPS), respectively. This review discusses clinical and genetic aspects of HCM and the role of NMD and UPS in the regulation of mutant proteins, evidence for impairment of UPS as a pathogenic factor, as well as potential therapies for HCM.
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Affiliation(s)
- Lucie Carrier
- Institute of Experimental and Clinical Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany.
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33
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Rodríguez JE, McCudden CR, Willis MS. Familial hypertrophic cardiomyopathy: basic concepts and future molecular diagnostics. Clin Biochem 2009; 42:755-65. [PMID: 19318019 DOI: 10.1016/j.clinbiochem.2009.01.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2008] [Revised: 01/24/2009] [Accepted: 01/28/2009] [Indexed: 11/26/2022]
Abstract
Familial hypertrophic cardiomyopathies (FHC) are the most common genetic heart diseases in the United States, affecting nearly 1 in 500 people. Manifesting as increased cardiac wall thickness, this autosomal dominant disease goes mainly unnoticed as most affected individuals are asymptomatic. Up to 1-2% of children and adolescents and 0.5-1% adults with FHC die of sudden cardiac death, making it critical to quickly and accurately diagnose FHC to institute therapy and potentially reduce mortality. However, due to the heterogeneity of the genetic defects in mainly sarcomere proteins, this is a daunting task even with current diagnostic methods. Exciting new methods utilizing high-throughput microarray technology to identify FHC mutations by a method known as array-based resequencing has recently been described. Additionally, next generation sequencing methodologies may aid in improving FHC diagnosis. In this review, we discuss FHC pathophysiology, the rationale for testing, and discuss the limitations and advantages of current and future diagnostics.
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Affiliation(s)
- Jessica E Rodríguez
- Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, NC 27599-7525, USA
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34
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Abstract
PURPOSE OF REVIEW Cardiac hypertrophy is a common phenotypic response of the heart to stimulants. It is associated with increased morbidity and mortality in various cardiovascular disorders. Genetic factors are important determinants of phenotypic expression of cardiac hypertrophy, whether in single-gene disorders or in complex traits. We focus on the molecular genetics of cardiac hypertrophy in various conditions with an emphasis on hypertrophic cardiomyopathy, a genetic paradigm of cardiac hypertrophic response. RECENT FINDINGS The molecular genetic basis of cardiac hypertrophy in single-gene disorders has been partially elucidated. Likewise, the impact of genetics on the expression of cardiac hypertrophy in the general population has been demonstrated. Identification of mutations in the Z disk proteins has expanded the spectrum of causal mutations beyond the thin and thick filaments of the sarcomeres. In addition, modifier loci have been mapped and shown to impart considerable effects on the expression of cardiac hypertrophy in hypertrophic cardiomyopathy. Elucidation of the molecular genetics of sarcomeric hypertrophic cardiomyopathy and many of the phenocopies has highlighted the limitations of clinical diagnosis as a determinant of management and prognostic advice. The findings have raised the importance of diagnosis and treatment algorithms, which are based on both genotype and phenotype information. SUMMARY Cardiac hypertrophy, regardless of the cause, is the phenotypic consequence of complex interactions between genetic and nongenetic factors.
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Affiliation(s)
- Ali J Marian
- The Brown Foundation Institute of Molecular Medicine, Center for Cardiovascular Genetic Research, The University of Texas Health Science Center, Houston, Texas 77030, USA.
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Marian A. Utilities and limitations of genetic testing for hypertropic cardiomyopathy. EXPERT OPINION ON MEDICAL DIAGNOSTICS 2008; 2:539-46. [PMID: 23495742 DOI: 10.1517/17530059.2.5.539] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Hypertropic cardiomyopathy (HCM) is a primary disease of cardiac myocytes, diagnosed clinically by the presence of cardiac hypertrophy in the absence of any known cause. Over a dozen causal genes and several hundred mutations for HCM have been identified. OBJECTIVE The utilities of genetic testing in accurate diagnosis, prognostication and treatment of HCM are reviewed. METHODS The existing data are reviewed. RESULTS/CONCLUSIONS There is considerable interest in genetic testing for HCM. However, heterogeneity of the causal genes and alleles has hampered the efforts to develop a simple comprehensive genetic screening test. At present, it is feasible to screen for the 5 most common causal genes, which collectively account for ∼ 60% of the HCM. Advances of deep resequencing technologies are expected to increase the yield considerably and, hence, increase the use of genetic testing in clinical practice. However, the utility of genetic testing for risk stratification is expected to be limited, as factors other than the causal genes also contribute to the development of the phenotype. A comprehensive approach that includes the information content of the causal mutations, the modifier genes and the non-genetic factors will be necessary for accurate risk stratification and genetic-based interventions.
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Affiliation(s)
- Aj Marian
- The University of Texas Health Science Center, The Brown Foundation Institute of Molecular Medicine, Center for Cardiovascular Genetic Research, Texas Heart Institute at St Luke's Episcopal Hospital, 6770 Bertner Street, DAC 900A, Houston, TX 77030, USA +1 713 500 2350 ; +1 713 500 2320 ;
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Analyzing pathogenic mutations of C5 domain from cardiac myosin binding protein C through MD simulations. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2008; 37:683-91. [DOI: 10.1007/s00249-008-0308-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2007] [Revised: 02/04/2008] [Accepted: 03/10/2008] [Indexed: 11/26/2022]
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Keren A, Syrris P, McKenna WJ. Hypertrophic cardiomyopathy: the genetic determinants of clinical disease expression. ACTA ACUST UNITED AC 2008; 5:158-68. [PMID: 18227814 DOI: 10.1038/ncpcardio1110] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2007] [Accepted: 11/23/2007] [Indexed: 11/09/2022]
Abstract
Hypertrophic cardiomyopathy (HCM), defined clinically by the presence of unexplained left ventricular hypertrophy, is the most common inherited cardiac disorder. This condition is the major cause of sudden death in the young (<30 years of age) and in athletes. The clinical phenotype is heterogeneous, and mutations in a number of sarcomeric contractile-protein genes are responsible for causing the disease in approximately 60% of individuals with HCM. Other inherited syndromes, as well as metabolic and mitochondrial disorders, can present as clinical phenocopies and can be distinguished by their associated cardiac and noncardiac features and on the basis of their unique molecular genetics. The mode of inheritance, natural history and treatment of phenocopies can differ from those of HCM caused by mutations in sarcomere genes. Detailed clinical evaluation and mutation analysis are, therefore, important in providing an accurate diagnosis in order to enable genetic counseling, prognostic evaluation and appropriate clinical management. This Review summarizes current knowledge on the genetics, disease mechanisms, and correlations between phenotype and genotype in patients with HCM, and discusses the implications of genetic testing in routine clinical practice.
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Affiliation(s)
- Andre Keren
- Department of Cardiology, Hadassah University Hospital, Jerusalem, Israel
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Eijssen LMT, van den Bosch BJC, Vignier N, Lindsey PJ, van den Burg CMM, Carrier L, Doevendans PA, van der Vusse GJ, Smeets HJM. Altered myocardial gene expression reveals possible maladaptive processes in heterozygous and homozygous cardiac myosin-binding protein C knockout mice. Genomics 2007; 91:52-60. [PMID: 18060737 DOI: 10.1016/j.ygeno.2007.09.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2006] [Revised: 08/29/2007] [Accepted: 09/23/2007] [Indexed: 12/13/2022]
Abstract
Familial hypertrophic cardiomyopathy (FHC) is an autosomal dominant disease characterized by left ventricular hypertrophy (LVH) predominantly affecting the interventricular septum. Cardiac myosin-binding protein C (cMyBP-C) mutations are common causes of FHC. Gene expression profiling was performed in left ventricles of 9-week-old wild-type mice, heterozygous cMyBP-C KO mice displaying asymmetric septal hypertrophy, and homozygous mice developing eccentric LVH. Knocking out one or two cMyBP-C genes leads primarily to gene expression changes indicating an increased energy demand, activation of the JNK and p38 parts of the MAPK pathway and deactivation of the ERK part, and induction of apoptosis. Altered gene expression for processes related to cardiac structure, contractile proteins, and protein turnover was also identified. Many of the changes were more pronounced in the homozygous KO mice. These alterations point to physiological and pathological adaptations in the prehypertrophic heterozygous KO mice and the hypertrophic homozygous mice.
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MESH Headings
- Animals
- Apoptosis/genetics
- Cardiomyopathy, Hypertrophic, Familial/genetics
- Cardiomyopathy, Hypertrophic, Familial/metabolism
- Cardiomyopathy, Hypertrophic, Familial/pathology
- Carrier Proteins/genetics
- Carrier Proteins/metabolism
- Chromosome Disorders/genetics
- Chromosome Disorders/metabolism
- Chromosome Disorders/pathology
- Extracellular Signal-Regulated MAP Kinases
- Gene Expression Profiling
- Gene Expression Regulation/genetics
- Heterozygote
- Homozygote
- Hypertrophy, Left Ventricular/genetics
- Hypertrophy, Left Ventricular/metabolism
- Hypertrophy, Left Ventricular/pathology
- MAP Kinase Kinase 4/genetics
- MAP Kinase Kinase 4/metabolism
- MAP Kinase Signaling System/genetics
- Mice
- Mice, Knockout
- Myocardium/metabolism
- Myocardium/pathology
- Oligonucleotide Array Sequence Analysis
- Ventricular Septum/metabolism
- Ventricular Septum/pathology
- p38 Mitogen-Activated Protein Kinases/genetics
- p38 Mitogen-Activated Protein Kinases/metabolism
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Affiliation(s)
- L M T Eijssen
- Department of Genetics and Cell Biology, Cardiovascular Research Institute Maastricht, Maastricht University, PO Box 616, 6200 MD Maastricht, The Netherlands
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39
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Stability and kinetic properties of C5-domain from myosin binding protein C and its mutants. Biophys J 2007; 94:1403-11. [PMID: 17965135 DOI: 10.1529/biophysj.107.106625] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The impact of three mutations of domain C5 from myosin binding protein C, correlated to Familial Hypertrophic Cardiomyopathy, has been assessed through molecular dynamics simulations based on a native centric protein modeling. The severity of the phenotype correlates with the shift in unfolding temperature determined by the mutations. A contact probability analysis reveals a folding process of the C5 domain originating in the region of DE and FG loops and propagating toward the area proximal to CD and EF loops. This suggests that mutation effects gain relevance in the proximity to the area where folding originates. The scenario is also confirmed by the analysis of the kinetics of 27 test mutations evenly distributed throughout the entire C5 domain.
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40
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Guardiani C, Cecconi F, Livi R. Computational analysis of folding and mutation properties of C5 domain of myosin binding protein C. Proteins 2007; 70:1313-22. [PMID: 17876814 DOI: 10.1002/prot.21621] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Thermal folding molecular dynamics simulations of the domain C5 of Myosin binding protein C were performed using a native-centric model to study the role of three mutations related to Familial Hypertrophic Cardiomyopathy. Mutation of Asn755 causes the largest shift of the folding temperature, and the residue is located in the CFGA' beta-sheet featuring the highest phi-values. The mutation thus appears to reduce the thermodynamic stability in agreement with experimental data. The mutations on Arg654 and Arg668, conversely, cause little change in the folding temperature and they reside in the low phi-value BDE beta-sheet, so that their pathological role cannot be related to impairment of the folding process but possibly to the binding with target molecules. As the typical signature of Domain C5 is the presence of a longer and destibilizing CD-loop with respect to the other Ig-like domains, we completed the work with a bioinformatic analysis of this loop showing a high density of negative charge and low hydrophobicity. This indicates the CD-loop as a natively unfolded sequence with a likely coupling between folding and ligand binding.
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Affiliation(s)
- Carlo Guardiani
- Centro Interdipartimentale per lo Studio delle Dinamiche Complesse Sezione INFN di Firenze, Italy
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42
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Oakley CE, Hambly BD, Curmi PMG, Brown LJ. Myosin binding protein C: structural abnormalities in familial hypertrophic cardiomyopathy. Cell Res 2004; 14:95-110. [PMID: 15115610 DOI: 10.1038/sj.cr.7290208] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The muscle protein myosin binding protein C (MyBPC) is a large multi-domain protein whose role in the sarcomere is complex and not yet fully understood. Mutations in MyBPC are strongly associated with the heart disease familial hypertrophic cardiomyopathy (FHC) and these experiments of nature have provided some insight into the intricate workings of this protein in the heart. While some regions of the MyBPC molecule have been assigned a function in the regulation of muscle contraction, the interaction of other regions with various parts of the myosin molecule and the sarcomeric proteins, actin and titin, remain obscure. In addition, several intra-domain interactions between adjacent MyBPC molecules have been identified. Although the basic structure of the molecule (a series of immunoglobulin and fibronectin domains) has been elucidated, the assembly of MyBPC in the sarcomere is a topic for debate. By analysing the MyBPC sequence with respect to FHC-causing mutations it is possible to identify individual residues or regions of each domain that may be important either for binding or regulation. This review looks at the current literature, in concert with alignments and the structural models of MyBPC, in an attempt to understand how FHC mutations may lead to the disease state.
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Affiliation(s)
- Cecily E Oakley
- Department of Pathology, University of Sydney, NSW 2006, Australia.
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43
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Maron BJ, Seidman JG, Seidman CE. Proposal for contemporary screening strategies in families with hypertrophic cardiomyopathy. J Am Coll Cardiol 2004; 44:2125-32. [PMID: 15582308 DOI: 10.1016/j.jacc.2004.08.052] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2003] [Revised: 07/30/2004] [Accepted: 08/27/2004] [Indexed: 11/22/2022]
Abstract
Screening families with hypertrophic cardiomyopathy (HCM) presents a common clinical problem to practicing cardiologists, internists, and pediatricians. The traditional recommended strategy for screening relatives in most HCM families calls for such evaluations with echocardiography (and electrocardiogram [ECG]) on a 12- to 18-month basis, usually beginning at about age 12 years. If such tests show no evidence of left ventricular hypertrophy, i.e., without one or more segments of abnormally increased wall thickness by the time full growth and maturation is achieved (at the age of about 18 to 21 years), it has been customary practice to conclude that HCM is probably absent and reassure family members accordingly that further echocardiographic testing is unnecessary. However, novel developments in the definition of the genetic causes of HCM have defined both substantial molecular diversity and heterogeneity of the disease expression including (in some relatives) incomplete phenotypic penetrance and delayed, late-onset left ventricular hypertrophy well into adulthood. These observations have unavoidably reshaped the customary practice of genetic counseling and established a new proposed paradigm for clinical family screening of HCM families. Therefore, in the absence of genetic testing, strong consideration should be given to extending diagnostic serial echocardiography past adolescence and into mid-life for those family members with a normal echocardiogram and ECG. Of note, recent developments in laboratory DNA-based diagnosis for HCM could potentially avoid the necessity for serial echocardiography in many such relatives.
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Affiliation(s)
- Barry J Maron
- Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, Minneapolis, Minnesota, USA.
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Mogensen J, Murphy RT, Kubo T, Bahl A, Moon JC, Klausen IC, Elliott PM, McKenna WJ. Frequency and clinical expression of cardiac troponin I mutations in 748 consecutive families with hypertrophic cardiomyopathy. J Am Coll Cardiol 2004; 44:2315-25. [PMID: 15607392 DOI: 10.1016/j.jacc.2004.05.088] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2004] [Accepted: 05/04/2004] [Indexed: 11/19/2022]
Abstract
OBJECTIVES The aim of this study was to evaluate the potential utility of genetic diagnosis in clinical management of families with hypertrophic cardiomyopathy (HCM) caused by mutations in the gene for cardiac troponin I (TNNI3). BACKGROUND Knowledge about the clinical disease expression of sarcomeric gene mutations in HCM has predominantly been obtained by investigations of single individuals (probands) or selected families. To establish the role of genetic diagnosis in HCM families, systematic investigations of probands and their relatives are needed. METHODS Cardiac troponin I was investigated by direct sequencing and fluorescent (F)-SSCP analysis in 748 consecutive HCM families. Relatives of HCM probands with TNNI3 mutations were invited for cardiovascular and genetic assessment. RESULTS The prevalence of TNNI3 mutations was 3.1%. Mutations appeared to cluster in exons 7 and 8. A total of 100 mutation carriers were identified in 23 families with 13 different mutations (6 novel). Disease penetrance was 48%. Patients were diagnosed from the second to eighth decade of life. The morphologic spectrum observed represented a wide range of HCM. Two offspring of clinically unaffected mutation carriers were resuscitated from cardiac arrest, and an additional four individuals died suddenly as their initial presentation. Six individuals experienced other disease-related deaths. CONCLUSIONS The clinical expression of TNNI3 mutations was very heterogeneous and varied both within and between families with no apparent mutation- or gene-specific disease pattern. The data suggest that disease development may be monitored by regular assessment of cardiac symptoms and electrocardiographic abnormalities. Genetic diagnosis of TNNI3 is valuable in identifying clinically unaffected mutation carriers at risk of disease development and facilitates accurate management and counseling.
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Affiliation(s)
- Jens Mogensen
- Department of Cardiological Sciences, St. George's Hospital Medical School, London, United Kingdom.
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García-Castro M, Reguero JR, Alvarez V, Batalla A, Soto MI, Albaladejo V, Coto E. Hypertrophic cardiomyopathy linked to homozygosity for a new mutation in the myosin-binding protein C gene (A627V) suggests a dosage effect. Int J Cardiol 2004; 102:501-7. [PMID: 16004897 DOI: 10.1016/j.ijcard.2004.05.060] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2004] [Revised: 04/20/2004] [Accepted: 05/17/2004] [Indexed: 11/21/2022]
Abstract
Mutations in the cardiac myosin-binding protein C gene (MYBPC3) are responsible for up to 50% of familial cases with hypertrophic cardiomyopathy (HC). Compared to patients with mutations in other sarcomeric genes, patients with MYBPC3 mutations would have a milder form of the disease, with a lower incidence of sudden cardiac death. Because most of the mutations have been found in only one family, it is currently difficult to establish a correlation between a particular mutation and the HC phenotype. The aim of our study was to contribute to understanding of the role of MYBPC3 mutations in HC. We analysed the MYBPC3 exons and intron flanking regions in 10 patients from 10 families with at least two HC cases. After direct sequencing of polymerase chain reaction (PCR) fragments, we found three new mutations in three families (V771M, V342D, and A627V). These changes affected evolutionary conserved amino acids and were not found in 100 healthy controls. The Ala 627>Val was found homozygous in a 47-year-old patient with a severe form of HC, while his mother and a nephew were heterozygous carriers and asymptomatic. This fact suggests a dosage effect for mutations at the MYPBC3 gene.
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Affiliation(s)
- Mónica García-Castro
- Genética Molecular-Instituto de Estudios nefrológicos (IRSIN-FRIAT), Hospital Central de Asturias (Maternidad), 33006-Oviedo, Spain
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García-Castro M, Reguero JR, Batalla A, Catalán F, Mayordomo J, Coto E. [Direct detection of malignant mutations in patients with hypertrophic cardiomyopathy]. Rev Esp Cardiol 2004; 56:1022-5. [PMID: 14563299 DOI: 10.1016/s0300-8932(03)77002-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We determined the prevalence of mutations considered malignant in the genes for beta-myosin heavy chain (MYH7, 11 mutations) and troponin T (TNNT2, 5 mutations) in 30 patients with hypertrophic cardiomyopathy aged 18 to 60 years, 83% of whom had familial antecedents of hypertrophic myocardiopathy or sudden death. Mutations were identified with polymerase chain reaction followed by restriction enzyme digestion and agarose gel electrophoresis. Direct analysis identified 16 mutations in 2 of the 30 patients (7%): one women diagnosed at the age of 25 years as carrying the MYH7453cysteine mutation, and a 60-year-old women with the TNNT2278 cysteine mutation. These cases illustrate the considerable clinical heterogeneity that characterizes carriers of these mutations. Clinical manifestations can range from severe hypertrophy or early sudden death to the absence of symptoms up to advanced age.
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Affiliation(s)
- Mónica García-Castro
- Laboratorio de Genética Molecular e Instituto Reina Sofía de Investigación Nefrológica, Hospital Central de Asturias, Oviedo, Asturias, España
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Zou Y, Song L, Wang Z, Ma A, Liu T, Gu H, Lu S, Wu P, Zhang dagger Y, Shen dagger L, Cai Y, Zhen double dagger Y, Liu Y, Hui R. Prevalence of idiopathic hypertrophic cardiomyopathy in China: a population-based echocardiographic analysis of 8080 adults. Am J Med 2004; 116:14-8. [PMID: 14706660 DOI: 10.1016/j.amjmed.2003.05.009] [Citation(s) in RCA: 182] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE To determine the prevalence of hypertrophic cardiomyopathy in China. METHODS This epidemiologic investigation was performed in 8080 adults from nine communities across nine provinces in China from October 2001 to February 2002, using a multistage, random sample design. Hypertrophic cardiomyopathy was defined as nondilated ventricular hypertrophy, documented by echocardiography, that was not caused by any known cardiac or systemic disease. RESULTS Of the 4064 men and 4016 women who were screened, 13 (0.16%; 9 men and 4 women) had definite echocardiographic evidence for hypertrophic cardiomyopathy. The age- and sex-adjusted prevalence was about 80 per 100,000 adults. CONCLUSION Hypertrophic cardiomyopathy is not rare in China. Based on the estimated prevalence, there are at least 1 million cases in China.
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Affiliation(s)
- Yubao Zou
- Sino-German Laboratory for Molecular Medicine, Beijing, China
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García-Castro M, Reguero JR, Batalla A, Díaz-Molina B, González P, Alvarez V, Cortina A, Cubero GI, Coto E. Hypertrophic cardiomyopathy: low frequency of mutations in the beta-myosin heavy chain (MYH7) and cardiac troponin T (TNNT2) genes among Spanish patients. Clin Chem 2003; 49:1279-85. [PMID: 12881443 DOI: 10.1373/49.8.1279] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Mutations in the cardiac beta-myosin heavy chain (MYH7) and cardiac troponin T (TNNT2) genes are reportedly responsible for up to 40% of familial cases with hypertrophic cardiomyopathy (HC). Although there are no mutational hotspots, most of the mutations are located in specific exons of the MYH7 and TNNT2 genes. Currently it is not possible to predict the phenotype in carriers of mutations in these genes, although it is widely accepted that mutations in the MYH7 gene predispose to severe HC, whereas TNNT2 mutations are frequently linked to sudden cardiac death (SCD) in spite of minimal hypertrophy. METHODS We sequenced exons 8, 9, 13-16, 19, 20, 22-24, and 30 of the MYH7 gene and exons 8, 9, 11, and 14-16 of the TNNT2 gene in 30 HC patients (18-60 years of age) from the region of Asturias (Northern Spain); 25 cases (80%) had a family history of the disease. Genomic DNA was amplified, and fragments were directly sequenced. Each DNA variant found in the patients was also analyzed in 200 healthy controls through single-strand conformation analysis. RESULTS Four of the probands had nucleotide changes absent in the healthy controls. Two cases had mutations previously described in the MYH7 gene (exon 14, Arg453Cys) or the TNNT2 gene (exon 16, Arg278Cys). Two cases had new mutations (MYH7 exon 22, Met822Val; TNNT2 exon 14, Lys247Arg) not found among the healthy controls. We found MYH7 Met822Val in a woman with a severe form of HC; the mutation was absent in her parents, indicating a de novo mutation. MYH7 R453C was present in a woman with mild HC, mother of a son who died from SCD. TNNT2 R278C was present in a woman with severe HC, but a sister and a daughter were mutation carriers and did not have hypertrophy. A patient with severe HC was carrier of TNNT2 247Arg. CONCLUSIONS Mutations in the MYH7 and TNNT2 genes can be found in patients without a family history of HC. However, compared with other populations MYH7 or TNNT2 mutations were rare among our HC patients. This study illustrates the extreme phenotypic heterogeneity in carriers of MYH7 or TNNT2 mutations.
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Affiliation(s)
- Mónica García-Castro
- Genética Molecular-Instituto de Investigación Nefrológica (IRSIN-FRIAT) and. Servicio de Cardiología, Hospital Central de Asturias, 33006 Oviedo, Spain
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50
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Roberts R, Sidhu J. Genetic Basis for Hypertrophic Cardiomyopathy: Implications for Diagnosis and Treatment. ACTA ACUST UNITED AC 2003; 1:128-34. [PMID: 15815132 DOI: 10.1111/j.1541-9215.2003.02110.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Familial hypertrophic cardiomyopathy is a genetic disease defined by cardiac hypertrophy in the absence of an increased external load. It is the most common inherited cardiac disorder occurring in 1 in 500 individuals. Ten genes exhibiting over 200 mutations have been identified. However, about 75% are due to mutations in just three genes: e-myosin heavy chain, cardiac troponin T, and myosin binding protein-C. Certain phenotypes are more common with certain genes, such as the myosin binding protein-C gene, which induces the disease predominantly in the fifth or sixth decade of life. Genetic animal models in the mouse and rabbit have helped to elucidate the pathophysiology. The primary defect imparted by the specific mutation alters contractile function, which stimulates release of various growth factors that induce secondary cardiac hypertrophy and fibrosis. Placebo single-blinded studies in the mouse indicate that losartan reverses the phenotype; in the rabbit, simvastatin essentially reversed the phenotype after 12 weeks of therapy. Clinical trials are ongoing in human familial hypertrophic cardiomyopathy.
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Affiliation(s)
- Robert Roberts
- Department of Medicine, Section of Cardiology, Baylor College of Medicine, Houston, TX 77030, USA.
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