Cardiac effects of in-utero exposure to antiretroviral therapy in HIV-uninfected children born to HIV-infected mothers

Prevention of mother to child HIV transmission (MTCT) has been a resounding public health success story. In the past 20 years, the rate of MTCT in the US has been reduced from 26% to under 1% using potent combination antiretroviral (cARV) regimens [1-4]. As the use of cARV regimens in pregnancy has increased, concerns have been raised regarding the potential risk of in utero cARV exposure on long-term outcomes among HIV-exposed but uninfected (HEU) children, including mitochondrial toxicity which has also been associated with cardiomyopathy in HIV-unexposed children [5-12]. Among HIV-infected children, cardiomyopathy was common prior to widespread use of cARV and was associated with high mortality [13]. However, a study of both HEU and HIV-infected children in the National Heart, Lung, and Blood Institute (NHLBI) Pediatric Pulmonary and Cardiac Complications of Vertically Transmitted HIV Infection Study (P2C2) born between 1990-1994 found no association between perinatal exposure to zidovudine (ZDV) monotherapy and abnormalities of left ventricular (LV) structure or function [14]. In another report, compared to the subset of ARV-unexposed HEU children in the P2C2 study, 136 children (96% exposed to cARV in utero) born between 2003-2006 in the NHLBI-funded Cardiovascular Status of Highly Active Antiretroviral Therapy (HAART) in HIV-Exposed Infants and Children cohort study (CHAART I) had significantly lower LV mass, septal wall thickness, and LV diameter, and higher LV contractility at age 2 years [15]. Since these prior studies were limited by their small sample size and/or they were conducted during an earlier era when there were fewer antiretroviral (ARV) options compared to the contemporary era which has more robust combination ARV combination therapy options, we evaluated the relationship between perinatal ARV drug exposure and echocardiographic measurements from the Pediatric HIV/AIDS Cohort Study (PHACS) Surveillance Monitoring for ART Toxicities (SMARTT) study.