Long-Term Survival Following Cardiac Arrest Without Implantable Defibrillator Protection in a Hypertrophic Cardiomyopathy Patient

Hypertrophic cardiomyopathy (HCM) is the most common cause of sudden cardiac death in young people. Implantable cardioverter defibrillator (ICD) is the optimal therapy in patients with HCM, both for primary or secondary prevention of sudden death. Left ventricular systolic function in HCM is usually normal. However, in few patients, HCM has been reported to progress to a state that is characterized by left ventricular dilation and systolic dysfunction, resembling dilated cardiomyopathy (DCM). Although arrhythmias are common in HCM, advanced or complete atrioventricular block (AV) is very rare. This case report describes a HCM patient who progressed to DCM with advanced AV block and survived 31 years following cardiac arrest without ICD protection.