Functional pulmonary valve regurgitation in the fetus

The purpose of this study was to determine the prevalence and the characteristics of functional pulmonary valve regurgitation in normally grown fetuses.

A prospective cross-sectional study.

A total of 1115 singleton fetuses between 18 and 41 weeks of gestation and who had normal heart anatomy, normal estimated weight for gestational age and normal flow velocity waveforms in the umbilical and middle cerebral arteries and umbilical vein were examined. Cases with agenesis, constriction or other abnormalities of the ductus arteriosus were excluded.

Examination of the pulmonary valve was performed by color Doppler echocardiography, pulsed wave Doppler and, if necessary, continuous wave Doppler in the short-axis view at the level of the origin of the great arteries and/or in a subcostal view of the right ventricular outflow tract and pulmonary trunk. If pulmonary valve regurgitation was detected by color Doppler flow imaging and confirmed by pulsed wave Doppler echocardiography, the maximum velocity of the regurgitant jets as well as their maximum lengths were measured.

The prevalence of functional pulmonary valve regurgitation was 0.54% (n = 6). Pulmonary valve regurgitation was part diastolic in four cases and holodiastolic in two cases, with maximum velocity of < or = 2.05 m/s and maximum length of 3-8 mm. Prenatal re-examination of five of the six fetuses with pulmonary valve regurgitation showed that pulmonary valve regurgitation was a transient phenomenon in four cases. The fetal outcome in the presence of transient pulmonary valve regurgitation was normal; pediatric echocardiographic examination in these six fetuses with transient pulmonary valve regurgitation showed no regurgitations or other cardiac anomalies.

Pulmonary valve regurgitation was functional in all six fetuses.