Treating congenital heart defects in babies still in the womb is a high-risk procedure, but one that can improve babies' outcomes after birth.
Researchers at Children's Hospital Boston and Brigham and Women's Hospital reviewed the cases of 80 fetuses who had prenatal cardiac interventions during a six-year period (most often to avert hypoplastic left heart syndrome, a life-threatening condition in which most of the structures on the left side of the heart are small and underdeveloped). The intervention was successful in 79 percent of fetuses. Although 43 percent developed unstable cardiac function during the procedure, all regained normal heart rate and ventricular function within about half an hour, and the cardiac procedure had to be halted in only six of these 34 fetuses. There were six fetal deaths within 72 hours, of whom four had developed unstable cardiac function during the procedure. Further follow-up of the babies with successful interventions will be crucial, say the researchers. Efforts are ongoing to further improve the safety of these minimally invasive but high-risk procedures.