[Idiopathic restrictive cardiomyopathy]

To characterize the idiopathic restrictive cardiomyopathy (RCM) through clinical manifestations and complementary tests and to analyze the surgical benefit on the correction of tricuspid regurgitation.

Five patients with RCM idiopathic were retrospectively studied, 4 female and 1 male, with ages ranging from 30 to 59 (mean 40) years. The patients presented heart failure due to restrictive syndrome and were submitted to chest X-ray, EKG, echocardiogram, right ventricular endomyocardial biopsy, hemodynamic study and surgery.

X-ray showed heart enlargement in all patients, but only one had pulmonary venous capillary congestion. EKG presented atrial fibrillation, complex QRS with low voltage on frontal axis, abnormal ventricular repolarization, right bundle branch block, inactive area and right ventricular hypertrophy. Complete atrioventricular block was observed in one patient. The echocardiogram study showed biatrial enlargement in all patients, and left ventricular dilatation in one patient with left ventricular dysfunction. Mild tricuspid regurgitation were observed in one patient and moderate in four. Two patients had mild mitral regurgitation. Diastolic dysfunction were observed at Doppler-cardiography in all patients. Right ventricular endomyocardial biopsy showed interstitial fibrosis, myocytes hypertrophy and myofibrils disarray. The hemodynamic study disclosed right ventricular hypertension in all patients. Three patients had hypotension in left ventricle and aorta. The left ventricular end diastolic pressure and pulmonary capillary pressure (pulmonary wedge pressure) were elevated in all patients. Dilated left ventricle with mild hypokinesia and right ventricular inferior hypokinesia and diastolic restriction were observed in one patient. One patient had similar pattern without diastolic restriction. Mild tricuspid regurgitation was observed in one patient, moderate in three and severe in one. Mild mitral regurgitation were observed in two patients. The restrictive pattern (deep and plateau) was present in three patients. Surgery were performed in all patients, and confirmed the mild tricuspid regurgitation in one and the moderate in four. De Vega plastia were performed in four patients.

Among the complementary methods, echocardiogram and hemodynamic study were those of higher contribution to the diagnosis of idiopathic RCM. The disease has a poor evolution, even with clinical or surgical treatment. Heart transplantation may would be the best procedure on patients with symptomatic idiopathic restrictive cardiomyopathy.