Abstract:

Objective

To investigate the prenatal ultrasound characteristics of isolated pulmonary stenosis （IPS） in fetuses associated with postnatal stenosis severity and surgical intervention outcomes.

Methods

A retrospective analysis was conducted on 59 cases of fetal IPS diagnosed from April 2018 to April 2023 at three prenatal diagnosis centers： the First Affiliated Hospital of Anhui Medical University， Anhui Maternal and Child Health Hospital， and the Second Affiliated Hospital of Anhui Medical University. Clinical data and prenatal ultrasound findings were collected and analyzed. Based on echocardiographic findings within the first week after birth， the cases were categorized into two groups： moderate-to-severe pulmonary stenosis and mild pulmonary stenosis. Additionally， the cases were further stratified into surgical and non-surgical groups based on whether they underwent surgical intervention. Differences in prenatal ultrasound parameters between groups were compared using univariate analysis， including Fisher’s exact test， Student’s t-test， or Mann-Whitney U test， as appropriate.

Results

Among the 59 prenatally diagnosed cases， 18 opted for pregnancy termination， while 41 continued the pregnancy to delivery， with all fetuses surviving. Compared with the mild pulmonary valve stenosis group （n=32）， the moderate-to-severe pulmonary valve stenosis group（n=9） had a higher proportion of patients with a pulmonary valve diameter/main pulmonary artery diameter ratio ＜0.5 on prenatal ultrasound， right ventricular abnormalities， and ≥3 abnormal indicators ［67% vs 22%；67% vs 6%； 78% vs 19%］， as well as a larger foramen ovale diameter ［6.40 （4.90， 8.05） mm vs 4.90 （4.43， 5.30）mm］； these differences were statistically significant （P=0.018， P＜0.001， P=0.002， Z=-2.175， and P=0.029，respectively）. Compared with the non-surgical group （n=33）， the surgical group （n=8） had a higher proportion of patients with a pulmonary valve annulus diameter/main pulmonary artery diameter ratio ＜0.5， post-stenotic dilation of the pulmonary artery， tricuspid regurgitation velocity ＞100 cm/s， right ventricular abnormalities，and ≥3 abnormal indicators ［75% vs 21%； 87% vs 36%； 62% vs 21%； 75% vs 6%； 75% vs 21%］， as well as a larger foramen ovale diameter； these differences were statistically significant （P=0.007， P=0.016， P=0.034，P＜0.001， P=0.007， Z=-2.881， and P=0.003， respectively）.

Conclusion

In fetuses with moderate-to-severe pulmonary valve stenosis and those requiring surgical intervention， the ratio of pulmonary valve annulus diameter to main pulmonary artery diameter， the incidence of right ventricular abnormalities， the size of the foramen ovale， and the number of abnormal parameters ≥3 are higher.

Key words: Isolated pulmonary stenosis, Fetus, Echocardiogram, Prognosis