Assessing a murmur, saving a life: current trends in the management of hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy, formerly called idiopathic hypertrophic subaortic stenosis (IHSS), is the leading cause of sudden cardiac death in young people. Hypertrophic cardiomyopathy is a non-dilated cardiomyopathy primarily affecting the left ventricle, left atria, intraventricular septum, and mitral valve. It is an autosomal dominant genetic disorder that impairs diastolic and systolic function. Diagnosis is complex due to the heterogeneity of the disease. Symptoms and morphology are not always related and clinical signs may be absent or limited to a soft systolic murmur. The first symptom of hypertrophic cardiomyopathy is frequently sudden cardiac death. Echocardiogram is an accurate diagnostic tool. Asymptomatic patients are generally not treated. Treatment for symptomatic patients begins with beta or calcium channel blockers. Antiarrhythmics may be added to protect against sudden cardiac death. Surgical intervention is done if other treatments fall and involves removal of a portion of the obstructive septum. Operative mortality is 5% with a 60% reduction in symptoms. A promising alternative to surgery is dual-chamber pacemakers. Patient and family teaching is the emphasis of long-term management.