AIDS-Associated Heart Disease -- Incidence and Etiology

BACKGROUND:

Cardiovascular abnormalities have been reported in Acquired Immunodeficiency Syndrome (AIDS) clinically, echocardiographically and at autopsy. Pericardial effusion, cardiac tamponade, echocardiographic abnormalities and clinical cardiomyopathy with right and left-sided congestive heart failure have all been reported as isolated case reports or in small retrospective series of patients with AIDS who had echocardiograms. The frequency with which abnormalities specifically related to AIDS were found in consecutively studied patients was not known in 1988 when the study began.

The etiology of these abnormalities was also unclear. Since HIV infection resulted in profound suppression of T-cell macrophage-mediated immunity in AIDS and since there were significant abnormalities in B-cell lymphocyte function resulting in abnormalities of humoral immunity, there were frequently life threatening superinfections by bacterial, fungal, parasitic, and viral organisms. Some of these, such as herpes simplex, cytomegalovirus, cryptococcosis, toxoplasmosis and histoplasmosis, were known to cause pericarditis and myocarditis in the absence of AIDS so the presence of definite myocardial disease in AIDS did not prove that the disease was due to the HIV organism.

Using echocardiography to study cardiac structure and function in a small series of patients with AIDS, abnormalities have been identified in from 25 to 75 percent of patients. All of these studies were retrospective; none was prospective with controls. Furthermore, all types of echocardiographic abnormalities have been described including the presence of pericardial fluid, mitral valve prolapse, chamber size abnormalities, and wall motion abnormalities. Although these abnormalities could have been due to infection with the HIV organism there were many other possible reasons for the echocardiographic abnormalities. Among AIDS patients there was a high incidence of intravenous drug and alcohol abuse, patients in whom cardiac abnormalities were common.

Since there were no echocardiographic studies comparing HIV antibody- positive groups of patients to appropriate controls, it was not known whether the high reported incidence of echocardiographic abnormalities was related specifically to the HIV infection, to superinfection with other organisms, or was related to factors other than AIDS.