Midgestation Fetal Pulmonary Annulus Size Is Predictive of Outcome in Tetralogy of Fallot

Abstract

Background Surgical management of tetralogy of Fallot (TOF) is increasingly moving towards valve-sparing approaches rather than transannular patch (TAP). We evaluate if fetal pulmonary valve (PV) size is predictive of postnatal course and surgical approach in TOF. Methods In this retrospective study, fetal and postnatal demographic, clinical and echocardiographic data on 66 patients diagnosed prenatally with TOF were collected. We compared those with mid-gestation PV z-score >-3.5 to those ≤ -3.5. We analyzed fetal and postnatal PV size and growth and outcomes between groups Results Gestational age at 1st fetal echo was 23 weeks (range 18-28). PV diameter and z-score on mid-gestation echo were 3.5 mm (1.3 to 6.0) and -2.8 (-0.5 to -6.0) respectively. Patients with PV z-score ≤-3.5 on 1st fetal echo had smaller PV diameter (4.5 vs. 5.0 mm, p=0.047) and PV z-score (-3.8 vs. -2.8 p<0.001) in late gestation and at time of surgery (6.0 mm vs. 7.0 mm, p=0.01; z-score= -2.9 vs. -1.7, p=0.007). Similarly, those with smaller fetal PV z-score had smaller main and branch pulmonary arteries at time of surgery. PV growth rate over gestation was similar between groups, while after birth PV growth rate was lower in those with smaller PV (0 mm/month vs. 0.6 mm/month, p=0.002). Those with smaller pulmonary valve were more likely to be cyanotic (p=0.05), to undergo surgery at < 1 month (p<0.01) and to have a TAP repair (p=0.01). Among patients undergoing valve-sparing repair, those with smaller PV had underwent more re-interventions for residual valvar PS (p<0.01). Conclusion Mid-gestation fetal PV size is predictive of postnatal PV and PA size in TOF. Mid-gestation PV size has implications for timing and type of surgical management as well as for need for re-intervention in valve-sparing repair patients and is therefore important to consider in prenatal counseling for TOF fetuses.

Cerebrovascular blood flow in patients with tetralogy of fallot: prediction for early surgical intervention

“…Previous studies have demonstrated that key prenatal echocardiographic features like pulmonary valve hypoplasia and reversal of ductal flow are predictive in determining degree of cyanosis . Our study validates that PV size associates with ESI later in pregnancy.…”

“…Given this, prior studies have demonstrated prenatal factors predictive for early intervention. These studies have shown that flow reversal in the arterial duct, small pulmonary valve size and failure of development of the pulmonary trunk has correlated with need for early intervention. Recent studies have evaluated cerebrovascular blood flow and flow dynamics in patients with congenital heart disease .…”

Fetal cardiac axis in tetralogy of Fallot: associations with prenatal findings, genetic anomalies and postnatal outcome

“…A pulmonary annulus Z ‐score of –4 or higher was reported to be a good marker for successful PVSS repair. Prenatally, a pulmonary valve Z ‐score ≤ –3.5 in the second trimester and increased pulmonary valve peak systolic velocity ≥ 87.5 cm/s were found to be useful in predicting need for TAP repair and earlier intervention.…”

Outcome and Associated Findings in Individuals with Pre- and Postnatal Diagnosis of Tetralogy of Fallot (TOF) and Prediction of Early Postnatal Intervention

“…Only a few previous studies have evaluated the association between fetal echocardiographic parameters and postnatal outcomes in TOF and the evaluated cohorts are often small [5][6][7][8][9][10].…”