The follow-up observation on the abnormal elevation of fetal pulmonary artery systolic pressure at middle and late stages by Doppler echocardiography

Abstract

Objective To investigate the outcome of fetus with abnormal increase of pulmonary artery systolic pressure at second and third trimester by color Doppler ultrasound. Methods Ninety-five fetuses with a little or mild tricuspid regurgitation (control group) and 60 fetuses with moderate and severe tricuspid regurgitation (observation group) were included. The degree, velocity, and differential pressure of tricuspid regurgitation were measured and the variations of baseline information and the measured value of pulmonary systolic pressure between the two groups were compared. As for the follow-up on observation group, the pressure of fetus with high pulmonary systolic pressure (>20 mmHg) was repeatedly measured every 4 weeks until it return to normal. Results There were significant differences in terms of gestational weeks, velocity and pressure of tricuspid regurgitation, as well as pulmonary systolic pressure between the two groups (P<0.001). Pulmonary systolic pressure was positively correlated with gestational weeks, velocity and pressure of tricuspid regurgitation (r=0.442, 0.998, 0.999; all P<0.001), but had no correlations with the age of pregnant women (r=-0.001, P=0.674). The follow-up revealed that, in observation group, 47 cases (78.3%, systolic pressure <50 mmHg) presented with the decreased pulmonary systolic pressure, the disappeared or the slight appeared regurgitation before birth, meanwhile, 13(21.7%, systolic pressure ≥50 mmHg) exhibited severe tricuspid regurgitation and persistent pulmonary elevation, with the highest of more than 70 mmHg accompanying the varying degrees of right heart failure. Only one of 13 fetuses died due to persistent pulmonary hypertension and hypoxia (oxygen saturation <45%). The fetal pulmonary artery systolic pressure of the remaining 12 cases recovered from 5 to 105 days after birth, with normal heart function. Conclusions The majority of fetal pulmonary arterial hypertension complicated with obvious tricuspid regurgitation is reversible functional alteration, which can restore normality in most cases before or after birth. Key words: Echocardiography, Doppler; Artery systolic pressure; Second and third trimester fetus; Tricuspid value insufficiency