The Medical Examiner's office calls to inform you that they are investigating the sudden death of one of your patients. The patient in question was a 23-year-old man recently evaluated in your office after an episode of syncope that occurred shortly after a funeral for a 21-year-old cousin who had also died suddenly. Your patient's episode of syncope was associated with transient mild dyspnea on exertion and palpitations. There was no associated chest pain. The patient denied prior medical illness.
He had never been told he had a heart murmur, and there was nothing in his history to suggest prior acute rheumatic fever. Physical exam revealed a forceful systolic heave. The chest radiograph showed cardiomegaly with slight atrial enlargement. An EKG confirmed the presence of left ventricular hypertrophy (LVH). Serum markers of cardiac injury (enzymes, troponin) were negative for myocardial infarction
The patient had been referred to a cardiologist for an echocardiogram to rule out hypertrophic cardiomyopathy, valvular heart disease, or coarctation of the aorta. The medical examiner relates that the patient collapsed suddenly at work while unloading a truck. Extended attempts to revive him were unsuccessful, and he was pronounced dead at the hospital a few hours later.
Dilated Cardiomyopathy Clinical: –Most common form of cardiomyopathy –Poor contraction of LV –CHF –Age 20 and 60 –Familial cases Enlarged heart, >900g, dilated, hypertrophied
Hypertrophic Cardiomyopathy Asymmetric septal hypertrophy Idiopathic hypertrophic sub-aortic stenosis Myocardial hypertrophy with abnormal diastolic filling and ventricular outflow obstruction 50% inherited as autosomal dominant Mutation in heavy chain beta-myosin
Hypertrophic Cardiomyopathy Morphology: –Hypertrophy in LV and septum –>800g Clinical: –Diastolic dysfunction –Dyspnea on exertion –Systolic murmur –Risk of ischemia –Common cause of sudden death in young athletes
Restrictive Cardiomyopathy Primary decrease in the ventricular compliance, impaired ventricular filling Caused by infiltrative process of the myocardium: –Endomyocardial fibrosis –Amyloidosis –Hemochromatosis
Restrictive Cardiomyopathy Morphology: –Endocardial thickening and fibrosis –Deposition of amyloid in amyloidosis, –Deposition of iron in hemochromatosis Clinical: –Diastolic dysfunction –Fatigue, dyspnea, chest pain