Cardiomyopathy (Dilated, Hypertrophic, Restrictive)

Cardiomyopathy is disease of the heart muscle itself, and its three classic types — dilated, hypertrophic and restrictive — can all cause heart failure, dysrhythmias and sudden cardiac death. Dilated cardiomyopathy, the most common, enlarges and weakens the ventricles so they cannot squeeze, giving a low ejection fraction and heart-failure signs; causes include coronary artery disease, heavy alcohol or cocaine use, viral myocarditis, pregnancy and chemotherapy such as doxorubicin. Hypertrophic cardiomyopathy thickens the wall and septum into a stiff ventricle that fills poorly and can block outflow; it is usually inherited and is the most common cause of sudden cardiac death in athletes under 35. Its murmur grows louder with Valsalva or standing. In hypertrophic disease the nurse questions nitrates, vasodilators and digoxin and prevents dehydration, because each worsens the obstruction, and expects a beta-blocker or verapamil or diltiazem instead. Restrictive cardiomyopathy, the rarest, leaves stiff ventricles, classically from amyloidosis. For every type, monitor the rhythm, weigh daily, watch for heart-failure signs and screen first-degree relatives of a client with hypertrophic disease.