[Syncope in hypertrophic (obstructive) cardiomyopathy].

Hypertrophic cardiomyopathy is the most common genetic cardiac disease. The most important pathophysiological finding is dynamic (outflow tract) obstruction of the left ventricle in about 70% of affected patients. Especially in younger patients, an increased risk of sudden cardiac death has been observed. Syncope and presyncope-in addition to extremely variable cardiac symptoms (dyspnea and angina)-are common. The etiology of syncope is complex. The most important aspect for diagnosis is a detailed history regarding the accompanying circumstances of the syncope. In principle, an attempt must be made to distinguish between rhythmogenic and hemodynamic causes. Diagnostic work-up should be performed under the criteria of a possible prognostic-with implantation of an implantable cardioverter-defibrillator (ICD) in patients at increased risk of sudden cardiac death-and symptomatic therapy. Depending on the underlying morphology and the experience of the surgeon, percutaneous septal ablation and operative myectomy are complementary options for symptomatic treatment if medical therapy with beta-blockers and/or verapamil is inadequate.