HIV-infected pregnant women frequently receive HAART, which is associated with reduced maternal-fetal transmission of HIV infection. This has resulted in a rapidly increasing number of seroreverters (HIV-uninfected infants born to HIV-infected women), representing the majority of infants in the United States exposed to HAART. Long-term consequences and toxicities associated with this exposure are not known, but severe cardiotoxicity is suggested in animal models. This study will utilize HIV seroreverter cohorts from the NIH-sponsored Women and Infants Transmission Study (WITS) and Pediatric Pulmonary and Cardiovascular Complications of Vertically Transmitted HIV Infections Study (P2C2) to determine how left ventricular (LV) structure and function, serum cardiac troponin T (cTnT), serum pro brain natriuretic peptide (proBNP), and serum high sensitivity C reactive protein (hsCRP) are affected by HAART exposure. In P2C2, patients were recruited from May 1990 to January 1994 from five clinical centers in the United States.