Fifty patients in stage IV of HIV infection (including 41 AIDS patients) were prospectively studied by echocardiography. Thirteen of them showed abnormalities: 4 had pericardial effusion, 1 endocarditis, 7 myocardial disorders and 1 primary pulmonary arterial hypertension. Pericardial effusion, also present in patients who had pleuropulmonary Kaposi's sarcoma, was not specific. Myocardial disorders concerned the diastolic function in 1 case, the segmental kinetics in 2 cases and the whole systolic function in 4 cases (3 had congestive myocardiopathy and 1 had transient systole alteration without left ventricular dilatation). The mechanism of global left ventricular disorders was multifactorial, and several hypotheses were discussed: infectious myocarditis, adrenergic or nutritional deficiency myocarditis, cardiotoxicity of antiviral drugs, common pathology with HIV encephalopathy. The prognosis of congestive myocardiopathy was poor in AIDS patients and undetermined in stage IV non-AIDS patients. Echocardiography is capable of detecting these lesions, and its use may contribute to a better care of these patients.