Medical, surgical and interventional management of hypertrophic cardiomyopathy with obstruction.

OPINION STATEMENT: Patients with hypertrophic cardiomyopathy (HCM) are classified as having hypertrophic obstructive cardiomyopathy (HOCM) if a left ventricular outflow tract (LVOT) gradient is present at rest or during provocation, as with Valsalva maneuver or exercise. Management of HCM in general and HOCM in particular encompasses (1) activity restriction with avoidance of volume depletion, (2) prevention of sudden cardiac death, (3) control of symptoms, and (4) screening of relatives. Those patients at high risk of sudden cardiac death (SCD) should be offered an implantable cardioverter-defibrillator (ICD). Pharmacologic treatment of symptoms in patients with HOCM consists of negative inotropic drugs, namely beta blockers, and disopyramide; a nondihydropyridine calcium channel blocker (CCB), usually verapamil, may be used in patients with noncardiac side-effects of beta blockers. Patients who have a dual-chamber pacemaker (PM) or ICD should undergo a trial of pacing with short atrioventricular (AV) delay. For patients with intolerable symptoms despite optimal conservative therapy, septal reduction therapy (SRT) should be considered and should be performed by experienced operators in institutions with multidisciplinary HCM programs. Younger patients with extreme hypertrophy are usually offered septal myectomy, while older patients, and those with important comorbidities are usually directed to alcohol septal ablation (ASA). For patients for whom either therapy is appropriate, there should be a balanced discussion with the patients of the benefits and risks of the 2 procedures.