CARDIOVASCULAR EFFECTS OF COCAINE IN NEONATES EXPOSED PRENATALLY

This blinded cross-sectional study was to determine whether chronic co caine exposure in utero produces abnormalities in left ventricular fun ction (shortening fraction), heart rate, rhythm, and conduction in ter m neonates. Three groups of neonates were evaluated by two-dimensional echo Doppler and 24 hour Hotter monitor, with studies initiated in th e first 24 hours of life. Group A (n = 32) neonates had a positive his tory of chronic maternal cocaine use in pregnancy (MCU+) and a positiv e neonatal urine cocaine test (NUC+). Group B (n = 23) neonates were M CU+ but NUC-. Group C (n = 32) neonates were MCU- and NUC-. Measured p arameters were compared statistically by analysis of variance, p < 0.0 5 was regarded as significant. Echocardiography showed no significant difference between groups A, B, and C for left ventricular shortening fraction. Hotter monitor likewise revealed no significant difference b etween groups in minimal, maximal, and average heart rate, or in the i ncidence of supraventricular and ventricular arrhythmias greater than 20 beats/h in the 24-hour period. None of the patients had atrioventri cular or bundle branch block. It is possible that the developmental st ate of the newborn heart makes it less responsive to the adverse effec ts of cocaine.