Fetal Doppler echocardiographic assessment of cardiac blood flow velocity in normal fetuses and in those with congenital heart disease.

Ninety fetal Doppler echocardiographic examinations were performed on 72 normal fetuses and 5 with congenital heart disease [2 pulmonary stenosis (PS), 1 pulmonary atresia (PA), 1 tetralogy of Fallot (TOF) and 1 endocardial cushion defect (ECD)] at 16 to 40 weeks of gestational age. The maximum transmitral (MVMax), transtricuspid (TVMax), transaortic (AVMax) and transpulmonary blood flow velocity waveforms (PVMax) were assessed. The detection rates for MVMax, TVMax, AVMax and PVMax in normal fetuses were 69.4%, 68.2%, 77.6% and 43.5%, respectively. MVMax, TVMax, AVMax and PVMax correlated well with gestational age, in the normal fetuses. However, there was no correlation between MVMax, TVMax, AVMax, PVMax and heart rate, in the normal fetuses, respectively. The TVMax/MVMax ratio was one and over in 53 of 55 normal fetuses (96.4%), and the PVMax/AVMax ratio was one and over in 11 of 25 normal fetuses (44%). In cases of PS, the TVMax was relatively low, but the PVMax was definitely high. The TVMax/MVMax ratios in cases of PS were 0.8 and 1.0, respectively. AVMax in a fetus with TOF was definitely low and markedly decreased in the case of ECD. Therefore, fetal Doppler echocardiography is a pertinent diagnostic tool which can be used to analyze cardiac hemodynamics in all fetuses, in utero.