Can sudden cardiac death be prevented?

Hypertrophic cardiomyopathy is regarded as the most common cause of sudden cardiac death in young people (including trained athletes). Introduction of implantable cardioverter-defibrillators to the hypertrophic cardiomyopathy patient population represents a new paradigm for clinical practice and perhaps the most significant advance in the management of this disease to date. Implantable defibrillators offer the only proven protection against sudden death by virtue of effectively terminating ventricular tachycardia/fibrillation and, in the process, altering the natural history of hypertrophic cardiomyopathy and providing the potential opportunity of normal or near-normal longevity for many patients. However, targeting the most appropriate candidates for prophylactic device therapy can be complex, compounded by the unpredictability of the underlying arrhythmogenic substrate, absence of a single dominant and quantitative risk marker in this heterogeneous disease, and the historical difficulty in assembling sufficiently powered prospective and randomized trials in large patient populations. Nevertheless, the current risk factor algorithm, when combined with a measure of individual physician judgment, is an effective strategy for identifying high-risk patients. Indeed, prevention of sudden death has now become an integral, albeit challenging, component of overall hypertrophic cardiomyopathy management.