The goal of our study was to evaluate the incidence of heart involvement in AIDS patients during various stages of the disease. Between January 1988 to September 1991, we conducted a prospective study in 114 anti-HIV positive patients. The patients, whose mean age (+/- SD) was 34.6 +/- 5.4 years (range 20 to 54), were divided into three groups: anti-HIV positive asymptomatic (n = 31; 27%), AIDS related complex (ARC) group IV-A (n = 11; 10%), and AIDS subgroups IV-C1 (n = 62; 54%) and IV-D (n = 10; 9%). Overall, 84 patients (74%) were i.v. drug abusers, 24 (21%) were homosexuals, and six (5%) were partners at risk. Zidovudine (AZT) was administered to 94 patients (82%). Opportunistic infections and/or secondary malignancies were detected in 72 patients (63%). Electrocardiographic changes were of little clinical relevance. Of 72 AIDS patients, 47 (65.2%) presented a cardiac involvement: 12 subjects (16.6%) were affected by a dilated cardiomyopathy, 13 (18%) by pericardial effusion, three (4.1%) by mitral valve prolapse, four (5.5%) by myocarditis, five (6.9%) by valvular bacterial endocarditis, and 10 (13.8%) by alterations of left ventricle regional contractility. During a mean follow-up period of 44 months, 29 AIDS patients (40.2%) died. Death was attributed to a cardiac event in four patients; autopsy could be performed in 24 of the 29 patients who died. Our results demonstrate that heart involvement is present in 45.6% of HIV-infected patients, but only in the end-stage of the disease (AIDS) and it is presumably due to opportunistic infections and/or secondary malignancies.(ABSTRACT TRUNCATED AT 250 WORDS)