Hypertrophic cardiomyopathy (HCM) is very heterogeneous, mostly asymptomatic disease characterized by thickening of cardiac walls in the absence of hypertension or valvular heart disease. Approximately half up to two thirds of patients with HCM are accompanied with intraventricular obstruction, which is most frequently subaortic. The patients are mostly asymptomatic, but some of them suffer from dyspnea, angina pectoris, syncope, and palpitations. Clinical course is heterogeneous and approximately 10-20 % of patients are at high risk of sudden death. Conventional treatment to relieve the symptoms consists of medications such as beta-blockers and calcium channel blockers. Alcohol septal ablation, myectomy or DDD pacing are performed in the highly symptomatic patients with the left ventricular outflow obstruction. Patients with an increased risk of sudden death are treated by implantation of cardioverter-defibrillator.