[Right ventricular dysplasia: clinical features compared with dilated cardiomyopathy].

Five patients with right ventricular dysplasia (RVD) and 28 patients with predominantly left sided dilated cardiomyopathy (DCM) were studied. RVD was characterised by syncope, recurrent sustained ventricular tachycardia, which typically had a left bundle branch block pattern on the surface electrocardiogram, right heart failure, and faint or absence of the right ventricular free wall on the myocardial scintigraphy. Two-dimensional echocardiographic, radionuclide angiographic, and contrast ventriculographic studies were typical of the right ventricular abnormalities in both Uhl's anomaly and arrhythmogenic right ventricular dysplasia. Two of them were died suddenly. Pathologic examinations showed "parchment-like" thinning of portions of the right ventricular free wall and its replacement by adipose tissue, although such degenerations were not found in the septum and the left ventricle. By contrast, DCM was characterised by exertional dyspnea and short run ventricular tachycardia, most of which had a right bundle branch block pattern. Ten of them had left ventricular myocardial defects on the scintigraphy, of whom five died suddenly. Hemodynamic data showed that left ventricular dysfunction was predominant more than right ventricle. Thus we postulate that these two syndromes are manifestations of a congenital, pathophysiologic process - the "involved right or left ventricle" syndrome.