Intrauterine pulmonary venous flow and restrictive foramen ovale in fetal hypoplastic left heart syndrome

ObjectivesWe sought to determine whether direct foramen ovale (FO) assessment or pulmonary venous (PV) flow patterns in fetal hypoplastic left heart syndrome (HLHS) correlate with clinical markers of postnatal left atrial (LA) hypertension severity associated with restrictive FO.BackgroundRestrictive FO places a newborn with HLHS at high risk of mortality and morbidity.MethodsWe reviewed the prenatal and postnatal echocardiograms and outcomes of 45 fetuses with variants of HLHS diagnosed since May 1999 to determine whether direct FO assessment or PV flow patterns correlate with clinical LA hypertension after birth.ResultsDirect FO assessment in utero showed a poor correlation with postnatal FO size, Pao2, base excess, and the need for atrial septoplasty (p > 0.05). In 40 fetuses with available PV spectra, three PV flow patterns were observed: 1) continuous forward flow with a small a-wave reversal (velocity time integral [VTI] for reverse/forward flow [VTIR/VTIF ratio