Hypertrophic cardiomyopathy (HCM) is characterized by left ventricular hypertrophy (typically asymmetric) that occurs in the absence of pressure overload or storage/infiltrative disease.
HCM demonstrates remarkable diversity in disease course, age of onset, pattern and extent of LVH, degree of obstruction, and risk for sudden cardiac death.
Exertional dyspnea and chest pain are the most common symptoms, presumably related to diastolic dysfunction, obstructive physiology, and ischemia.
First line therapy is medical treatment with beta or calcium channel blockers used to prolong diastolic filling and blunt dynamic intra-cavitary gradients.
Medically refractory symptoms are caused by severe obstruction from systolic anterior motion of the mitral valve; these patients are candidates for invasive septal reduction therapy with surgical myectomy or alcohol septal ablation.
Patients with HCM are at increased risk for sudden death, annual rate of SCD is ~1%. ICDs are recommended for all patients with prior arrest/sustained ventricular tachycardia (class I recommendation).
References
Ho CY. Hypertrophic Cardiomyopathy in 2012. Circulation. 125(11):1432-8, 2012 Mar 20.
