A Primer on Arrhythmias in Patients with Hypertrophic Cardiomyopathy

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Alcalai R, Seidman JG, Seidman CE. Genetic basis of hypertrophic cardiomyopathy: from bench to the clinics. J Cardiovasc Electrophysiol. 2008;19:104–10.

Maron BJ. Hypertrophic cardiomyopathy; a systemic review. JAMA. 2002;287:1308–20.

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Adabag AS, Casey SA, Kuskowski MA, Zenovich AG, Maron BJ. Spectrum and prognostic significance of arrhythmias on ambulatory Holter electrocardiogram in hypertrophic cardiomyopathy. J Am Coll Cardiol. 2005;45:697–704.

Bahl A, Saikia UN, Talwar KK. Familial conduction system disease associated with hypertrophic cardiomyopathy. Int J Cardiol. 2008;125:e44–7.

•• Agarwal S, Tuzcu EM, Desai MY, et al. Updated meta-analysis of septal alcohol ablation vs myectomy for hypertrophic cardiomyopathy. J Am Coll Cardiol. 2010;55:823–34. Meta-analysis of 12 studies in which there was no significant differences in short term risk, long term mortality and functional status between patients treated with alcohol septal ablation compared with surgical myectomy. Patients treated with alcohol septal ablation were at higher risk of need for a pacemaker after the procedure.

Talreja DR, Nishimura RA, Edwards WD, et al. Alcohol septal ablation vs surgical septal myectomy: comparison of effects on atrioventricular conduction tissue. J Am Coll Cardiol. 2004;44:2329–32.

•• Gersh BJ, Maron BJ, Bonow RO, et al. 2011 ACCF/AHA guideline for the diagnosis and treatment of hypertrophic cardiomyopathy: a report of the American college of cardiology foundation/American heart association task force on practice guidelines. circulation . 2011;124:e783–831. HCM guidelines update the 2003 Guidelines. In this 70 page document, literature on the care of the HCM patient is reviewed and comprehensive recommendations cover everything from diagnosis, risk assessment, management and familial screening.

Epstein AE, DiMarco JP, Ellenbogen KA, et al. ACC/AHA/HRS 2008 guidelines for device-based therapy of cardiac rhythm abnormalities: a report of the American college of cardiology/American heart association task force on practice guidelines (writing committee to revise the ACC/AHA/NASPE 2002 guideline update for implantation of cardiac pacemakers and antiarrhythmia devices) developed in collaboration with the American association for thoracic surgery and society of thoracic surgeons. J Am Coll Cardiol. 2008;51:e1–62.

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Olivotto I, Cecchi F, Casey SA, Dolara A, Traverse JH, Maron BJ. Impact of atrial fibrillation on the clinical course of hypertrophic cardiomyopathy. Circulation. 2001;104:2517–24.

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• Kubo T, Kitaoka H, Okawa M, et al. Gender-specific differences in the clinical features of hypertrophic cardiomyopathy in a community-based Japanese population: results from Kochi RYOMA study. J Cardiol. 2009;56:314–9. In a community based cohort of 9 Japanese hospitals 261 patients were found to have a diagnosis of HCM, including 88 (34 %) females. Females were diagnosed later in life, had a higher familial ratio, more often were symptomatic, and had a higher frequency of thrombo-embolism.

Robinson K, Frenneaux MP, Stockins B, Karatasakis G, Poloniecki JD, McKenna WJ. Atrial fibrillation in hypertrophic cardiomyopathy: a longitudinal study. J Am Coll Cardiol. 1990;15:1279–85.

Nistri S, Olivotto I, Betocchi S, et al. Prognostic significance of left atrial size in patients with hypertrophic cardiomyopathy (from the Italian registry for hypertrophic cardiomyopathy). Am J Cardiol. 2006;98:960–5.

• Pujadas S, Vidal-Perez R, Hidalgo A, et al. Correlation between myocardial fibrosis and the occurrence of atrial fibrillation in hypertrophic cardiomyopathy: a cardiac magnetic resonance imaging study. Eur J Radiol. 2010;75:e88–91. Of 67 HCM patients studied with CMR, atrial fibrillation was present in 17 (25 %). Atrial fibrillation was more frequent in patients with myocardial fibrosis.

Losi MA, Betocchi S, Aversa M, et al. Determinants of atrial fibrillation development in patients with hypertrophic cardiomyopathy. Am J Cardiol. 2004;94:895–900.

Ozdemir O, Soylu M, Demir AD, et al. P-wave durations as a predictor for atrial fibrillation development in patients with hypertrophic cardiomyopathy. Int J Cardiol. 2004;94:163–6.

•• Papavassiliu T, Germans T, Fluchter S, et al. CMR findings in patients with hypertrophic cardiomyopathy and atrial fibrillation. J Cardiovasc Magn Reson. 2009;11:34. Of 87 patients undergoing CMR, atrial fibrillation was present in 37 (42 %). Left atrial volume and diastolic dysfunction correlated with the risk of atrial fibrillation.

• Pedrosa RP, Drager LF, Genta PR, et al. Obstructive sleep apnea is common and independently associated with atrial fibrillation in patients with hypertrophic cardiomyopathy. Chest. 2010;137:1078–84. Of 80 consecutive patients with HCM sleep apnea was present in 32 (40 %). The presence of sleep apnea correlated with larger left atrial size. Sleep apnea was an independent predictor of atrial fibrillation.

Moon JC, Reed E, Sheppard MN, et al. The histologic basis of late gadolinium enhancement cardiovascular magnetic resonance in hypertrophic cardiomyopathy. J Am Coll Cardiol. 2004;43:2260–4.

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Nagai T, Ogimoto A, Okayama H, et al. A985G polymorphism of the endothelin-2 gene and atrial fibrillation in patients with hypertrophic cardiomyopathy. Circ J. 2007;71:1932–6.

Fuster V, Ryden LE, Cannom DS, et al. ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation: a report of the American college of cardiology/American heart association task force on practice guidelines and the European society of cardiology committee for practice guidelines (writing committee to revise the 2001 guidelines for the management of patients with atrial fibrillation): developed in collaboration with the European heart rhythm association and the heart rhythm society. Circulation. 2006;114:e257–354.

•• Connolly SJ, Ezekowitz MD, Yusuf S, et al. Dabigatran vs warfarin in patients with atrial fibrillation. N Engl J Med. 2009;361:1139–51. A landmark trial of a direct thrombin inhibitor vs warfarin in 18,113 patients with nonvalvular atrial fibrillation. Higher dose dabigatran was superior to warfarin in the prevention of strokes and systemic embolism and the bleeding risk was similar.

•• Patel MR, Mahaffey KW, Garg J, et al. Rivaroxaban vs warfarin in nonvalvular atrial fibrillation. N Engl J Med. 2011;365:883–91. Another landmark trial in which a factor Xa inhibitor was noninferior to warfarin in 14,264 patients with atrial fibrillation. There was no difference in the risk of bleeds.

•• Granger CB, Alexander JH, McMurray JJ, et al. Apixaban vs warfarin in patients with atrial fibrillation. N Engl J Med. 2011;365:981–92. Another factor Xa inhibitor in 18,201 patients with atrial fibrillation showed superiority in the prevention of stroke and systemic thrombo-embolism. In this trial there was also less bleeding and decreased overall mortality.

McKenna WJ, Harris L, Rowland E, et al. Amiodarone for long-term management of patients with hypertrophic cardiomyopathy. Am J Cardiol. 1984;54:802–10.

• Di Donna P, Olivotto I, Delcre SD, et al. Efficacy of catheter ablation for atrial fibrillation in hypertrophic cardiomyopathy: impact of age, atrial remodelling, and disease progression. Europace. 2010;12:347–55. Sixty-one patients with HCM and atrial fibrillation underwent fairly standard atrial fibrillation ablations. 52 % required redo procedures and antiarrhythmic agents were continued in 54 %. Of the entire cohort 67 % were in sinus rhythma at a followup of 29 months.

Sherrid MV, Barac I, McKenna WJ, et al. Multicenter study of the efficacy and safety of disopyramide in obstructive hypertrophic cardiomyopathy. J Am Coll Cardiol. 2005;45:1251–8.

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• Camm AJ, Kirchhof P, Lip GY, et al. Guidelines for the management of atrial fibrillation: the task force for the management of atrial fibrillation of the European Society of cardiology (ESC). Eur Heart J. 2010;31:2369–429. Guidelines for the management of atrial fibrillation in all patients published by the European Society of Cardiology. For patients with HCM, amiodarone and disopyramide are listed for antiarrhythmics.

Gaita F, Di Donna P, Olivotto I, et al. Usefulness and safety of transcatheter ablation of atrial fibrillation in patients with hypertrophic cardiomyopathy. Am J Cardiol. 2007;99:1575–81.

Bunch TJ, Munger TM, Friedman PA, et al. Substrate and procedural predictors of outcomes after catheter ablation for atrial fibrillation in patients with hypertrophic cardiomyopathy. J Cardiovasc Electrophysiol. 2008;19:1009–14.

Kilicaslan F, Verma A, Saad E, et al. Efficacy of catheter ablation of atrial fibrillation in patients with hypertrophic obstructive cardiomyopathy. Heart Rhythm. 2006;3:275–80.

Liu X, Ouyang F, Mavrakis H, et al. Complete pulmonary vein isolation guided by three-dimensional electroanatomical mapping for the treatment of paroxysmal atrial fibrillation in patients with hypertrophic obstructive cardiomyopathy. Europace. 2005;7:421–7.

Callans DJ. Ablation of atrial fibrillation in the setting of hypertrophic cardiomyopathy. J Cardiovasc Electrophysiol. 2008;19:1015–6.

Calkins H, Brugada J, Packer DL, et al. HRS/EHRA/ECAS expert consensus statement on catheter and surgical ablation of atrial fibrillation: recommendations for personnel, policy, procedures and follow-up. a report of the heart rhythm society (HRS) task force on catheter and surgical ablation of atrial fibrillation. Heart Rhythm. 2007;4:816–61.

Chen MS, McCarthy PM, Lever HM, Smedira NG, Lytle BL. Effectiveness of atrial fibrillation surgery in patients with hypertrophic cardiomyopathy. Am J Cardiol. 2004;93:373–5.

Matsui Y, Fukada Y, Imai T, Naito Y, Sasaki S. Combined cox maze procedure, septal myectomy, and mitral valve replacement for severe hypertrophic obstructive cardiomyopathy complicated by chronic atrial fibrillation. Ann Thorac Cardiovasc Surg. 2003;9:323–5.

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Maron BJ, Shen WK, Link MS, et al. Efficacy of implantable cardioverter-defibrillators for the prevention of sudden death in patients with hypertrophic cardiomyopathy. N Engl J Med. 2000;342:365–73.

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• Rubinshtein R, Glockner JF, Ommen SR, et al. Characteristics and clinical significance of late gadolinium enhancement by contrast-enhanced magnetic resonance imaging in patients with hypertrophic cardiomyopathy. Circ Heart Fail. 2010;3:51–8. Of 424 patients with HCM undergoing CMR,56 % had late gadolinium enhancement. Late gadolinium enhancement did not predict symptoms of heart failure or angina, but did predict for nonsustained ventricular tachycardia, and a combined endpoint of ICD shock or sudden cardiac death.

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Maron BJ, Estes 3rd NA, Maron MS, Almquist AK, Link MS, Udelson JE. Primary prevention of sudden death as a novel treatment strategy in hypertrophic cardiomyopathy. Circulation. 2003;107:2872–5.

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•• Spirito P, Autore C, Rapezzi C, et al. Syncope and risk of sudden death in hypertrophic cardiomyopathy. Circulation. 2009;119:1703–10. A large series of 1511 HCM patient of which 153 had unexplained syncope. Over a nearly 6 year followup unexplained syncope within 6 months of initial evaluation predicted for life threatening arrhythmias in follow-up.

Spirito P, Bellone P, Harris KM, Bernabo P, Bruzzi P, Maron BJ. Magnitude of left ventricular hypertrophy and risk of sudden death in hypertrophic cardiomyopathy. N Engl J Med. 2000;342:1778–85.

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•• Maron BJ. Contemporary insights and strategies for risk stratification and prevention of sudden death in hypertrophic cardiomyopathy. Circulation. 2010;121:445–6. A review of sudden cardiac death in HCM patients by one of the leading investigators in the field.

•• Maron BJ, Maron MS, Semsarian C. Double or compound sarcomere mutations in hypertrophic cardiomyopathy: a potential link to sudden death in the absence of conventional risk factors. Heart Rhythm. 2012;9:57–63. In a 3 center study with 18 probands, patients with more than 1 HCM mutation were at higher risk of sudden cardiac death.

Maron BJ, Ackerman MJ, Nishimura RA, Pyeritz RE, Towbin JA, Udelson JE. Task force 4: HCM and other cardiomyopathies, mitral valve prolapse, myocarditis, and Marfan syndrome. J Am Coll Cardiol. 2005;45:1340–5.

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Maron BJ, Spirito P, Shen WK, et al. Implantable cardioverter-defibrillators and prevention of sudden cardiac death in hypertrophic cardiomyopathy. JAMA. 2007;298:405–12.

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• Lin G, Nishimura RA, Gersh BJ, et al. Device complications and inappropriate implantable cardioverter defibrillator shocks in patients with hypertrophic cardiomyopathy. Heart. 2009;95:709–14. In a cohort of 181 patients with HCM and ICDs, younger age predicted for more inappropriate shocks. The rate of inappropriate shocks was 5.3% a year.