New trends in treatment of hypertrophic cardiomyopathy.

The management of patients with hypertrophic cardiomyopathy (HCM) has evolved markedly over the past 20 years, particularly with the rising number of indications for implantable cardiac defibrillators (ICDs) and alcohol septal ablation (ASA). However, medical therapies targeted to improve quality of life are underused; when resting and/or exercise obstruction is present, an incremental and additive approach should be used based on a high dosage of beta-blockers, verapamil and/or disopyramide. Radiofrequency catheter ablation of atrial fibrillation or A-V node has been proposed in some instances. Treatment of syncope or presyncope due to an abnormal blood pressure response during exercise remains challenging. Only patients with obstruction who remain severely symptomatic despite maximal medical therapy should be considered for invasive procedures, including dual-chamber (DDD) pacing, ASA or surgery. The reported complication rates of ASA (essentially complete A-V block, incidence above 5-10%, with mortality rates ranging from 0-4%) and the benefits at medium-term follow-up appear comparable to those observed after myectomy, which, according to guidelines, should remain the primary treatment for most severely symptomatic drug-refractory young patients with obstruction. While the overall survival of patients with HCM is similar to that of the general population, detection of patients at high risk of sudden cardiac death remains challenging, particularly in the young, and indications for ICDs in high risk patients without prior cardiac arrest should be patient- and family-orientated.