Restrictive cardiomyopathy is rare in the western world and in Europe. Diseases that cause damage to the muscle and restrict the flow of blood into the ventricle include amyloidosis, sarcoidosis, hemochromatosis, scleroderma, Adriamycin toxicity, and heart involvement by infectious agents. The most common cause of restrictive cardiomyo-pathy, especially in tropical regions, is endomyocardial fibrosis.
The damage to the muscle in these diseases causes the ventricular walls to become excessively rigid and the main abnormality is impaired relaxation and compliance that impedes the filling of the ventricle. Less blood is held within the ventricle and thus less blood is expelled into the aorta and systemic circulation. When the supply of blood to organs becomes inadequate, heart failure is diagnosed. This situation is due mainly to poor diastolic filling of the ventricle rather than to a decrease in the force of contraction of the ventricular muscle (systolic dysfunction) which is the most common cause for heart failure.
A. Clinical Features
In the tropics endomyocardial fibrosis may result in intermittent fever, shortness of breath, cough, palpitations, edema, and tiredness. Symptoms and signs of heart failure must be differentiated from constrictive pericarditis. Endomyocardial fibrosis may mimic the hemodynamic and clinical features of constrictive peritonitis. Chest x-ray or fluoroscopy may show calcification of the right and left ventricular apical myocardium due to thrombus formation, calcification of all fibrosis, and calcification of the endocardial region. The apex of the heart may be completely obliterated. Blood tests may reveal increased eosinophils (hypereosinophilia). Echocardiogram typically shows obliteration of the apices of the ventricle with echogenic masses. Also, extensive myocardial calcification may be detected.

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