Hypertrophic cardiomyopathy with massive hypertrophy, amiodarone treatment and high defibrillation threshold at cardioverter-defibrillator implant

Spirito et al. [ [1] ] recently reported on the high risk of sudden cardiac death in patients affected by hypertrophic cardiomyopathy presenting a pattern of massive left ventricular hypertrophy at cross-sectional echocardiogram (intraventricular septum thickness of 30 mm or more). These findings, together with the data reported by Maron et al. [ [2] ] on the outcome of patients with hypertrophic cardiomyopathy following implant of a cardioverter–defibrillator, both for secondary and primary prevention of sudden cardiac death, strongly suggest the implant of these devices in appropriately selected patients. These observations will probably lead to an increasing number of cardioverter–defibrillator implants and in this case some considerations on the potential problems that may occur at implant appear to be clinically useful. The overall experience on cardioverter–defibrillator implants, mainly based on coronary artery disease patients, has shown that relatively high defibrillation thresholds may be found in some patients, especially in those under chronic amiodarone treatment [ 3 , 4 , 5 , 6 ].