Definition

Dilated cardiomyopathy (DCM) is a disease of cardiac muscle characterized by dilation of the cardiac chambers and reduction in ventricular contractile function.

Epidemiology

DCM is the most common form of nonischemic cardiomyopathy and is responsible for approximately 10,000 deaths and 46,000 hospitalizations each year. The lifetime incidence of DCM is about 30 cases per 100,000 persons.

Pathophysiology

• DCM may be secondary to progression of any process that affects the myocardium, and dilation is directly related to neurohormonal activation. Familial DCM accounts for up to 50% of cases and is likely underestimated.^1,2
• Dilation of the cardiac chambers and varying degrees of hypertrophy are anatomic hallmarks. Tricuspid and mitral regurgitation are common because of the effect of chamber dilation on the valvular apparatus.
• Atrial and ventricular arrhythmias are present in as many as one-half of these patients and contribute to the high incidence of sudden death in this population.