Echocardiographic Aspects of Restrictive Cardiomyopathy: Their Relationship with Pathophysiology.

BACKGROUND AND METHODS: We studied 17 patients with restrictive cardiomyopathy; eight had biventricular restriction (type A), four had left ventricular restriction (type B), and five had only right ventricular restriction (type C). RESULTS: Type A disease was characterized by pulmonary and systemic venous congestion. The restrictive pattern was found in the inlet of both ventricles. Both atria were enormous, with small or normal-size ventricles. Differential diagnosis included constrictive pericarditis and systolic pump dysfunction. Type B restriction disease was characterized by venous pulmonary congestion, pulmonary hypertension, and important dilatation of the left atrium and right cavities with a small or normal-size left ventricle; the restrictive pattern was found only in the affected left ventricle. CONCLUSIONS: The clinical picture resembles that of rheumatic mitral valve disease with right ventricular failure. Type C disease had restriction only in the inlet of right ventricle, with giant right atrium, systemic venous hypertension with low flow, and normal pressure of pulmonary artery and left heart. Differential diagnosis included Ebstein's anomaly of tricuspid valve. The etiology of type A disease was amyloid, endomyocardial fibrosis of ventricles and idiopathic interstitial fibrosis. Asymmetric types were always caused by Davies' disease.