Objective: To investigate the effect of different operation time to percutaneous balloon pulmonic valvuloplasty (PBPV) to critical pulmonary valve stenosis (CPS).
Method: Twenty-one infants (age ≤ 60 days at operating day) suffered from CPS, diagnosed by fetal echocardiogram and confirmed by echocardiography after birth, were enrolled in this case-control-study with written informed consent during April 2007 to December 2011. Of the 21 cases, 7 had prenatal diagnosis in our prenatal diagnosis center (prenatal group, Pre) and 14 were referred from other hospitals, who were divided into postpartum group A (Post A, referred within 28 days after birth) and postpartum group B (Post B, referred 29 to 60 days after birth). To Pre-group, the integrative interventional protocol was cautiously made by the consultative specialists, including intrauterine diagnosis, perinatal care and urgent PBPV soon after birth. To Post-group, emergency PBPV was preformed after the referral. Tei index of right ventricular and pressure-gradient (PG) between right ventricular and pulmonary artery were measured before and at different time points one year after PBPV.
Result: The values of SpO2 in Pre-group ranged from 82%-92% (86.57% ± 5.34%) under the state of continuous intravenous infusion of alprostadil. PBPV was successfully preformed within 3-6 days after birth. The values of SpO2 increased to 97.33% ± 1.15% post procedure. The values of PG pre- and post- procedure were (86.34 ± 11.77) mm Hg and (31.43 ± 8.46) mm Hg respectively. Preoperative RV Tei-index was 0.68 ± 0.05, it decreased rapidly after procedure, and recovered to normal one month after procedure. Only one case showed restenosis seven months after procedure and repeated PBPV. Fourteen referral cases (6 cases in Post A group and 8 cases in Post B group, accompanied in 1 and 3 cases with heart failure), the values of SpO2 ranged from 83%-91% under state of continuous intravenous infusion of alprostadil. And the operating time was 10-57 days after birth. The values of SpO2 recovered to normal post procedure, and heart failure alleviated. Increased preoperative RV pressure obviously decreased significantly post-procedure. And increased Tei-index declined gradually, at one-year follow-up, the value of Tei-index in Post A group recovered to normal, whereas that of Post B was (0.51 ± 0.06), compared to Pre and Post A groups, the difference was significant (P < 0.05) . One case showed restenosis nine months after procedure and repeated PBPV was performed. The hypoxic exposure durations were (4.43 ± 0.68) , (16.33 ± 4.46) , (41.25 ± 9.19) , respectively, and the difference among the three groups was significant (P < 0.05).
Conclusion: To the fetuses with definite prenatal diagnosis of critical pulmonary valve stenosis, preoperative general condition can be adjusted to more suitable for emergency operation. Early PBPV can achieve shorter hypoxic exposure and better recovery of right ventricular function post procedure. Perinatal integrated intervention for CPS can significantly improve the prognosis and quality of life in this patient population.