The impact of pulmonary valve replacement on pregnancy outcomes in women with tetralogy of Fallot

Background: Pregnant women with repaired tetralogy of Fallot (rTOF) are at increased risk of adverse outcomes. Although pre-pregnancy pulmonary valve replacement (PVR) may be considered in some women to attenuate risk, published data to support this practice are lacking. Our objective was to explore the impact of pre-pregnancy PVR on pregnancy outcomes in rTOF.

Methods: Women with rTOF and cardiovascular magnetic resonance imaging (CMR) before and after pregnancy were included if CMR studies were completed within 3 years of pregnancy. Subjects were compared according to presence (+) or absence (-) of PVR at pre-pregnancy CMR. Pregnancy outcomes (cardiovascular, obstetric, and fetal/neonatal) were documented.

Results: Of the 29 study women identified, 7 were PVR+ and 22 were PVR-. Post-pregnancy, the PVR- group demonstrated interval increase in indexed right ventricular end-diastolic volumes (RVEDVi) (157 ± 28 versus 166 ± 33 ml/m², p = 0.003) and end-systolic volumes (RVESVi) (82 ± 17 versus 89 ± 20 ml/m², p = 0.003) as compared with pre-pregnancy, but no significant change in RV ejection fraction, RV mass, or left ventricular measurements. In the PVR+ group, there were no interval changes in RV measurements pre-versus post pregnancy. Interval rate of change in RVESVi of PVR- exceeded PVR+ women (+3.7 ± 5.0 versus -2.2 ± 5.0 ml/m²/year, p = 0.03). Pregnancy outcomes did not differ in PVR+ versus PVR- women.

Conclusions: Pregnancy outcomes did not differ according to PVR status in our cohort. While RV volumes remained unchanged in PVR+ women, interval RV dilation was observed in PVR- women. Additional study of a larger population with longer follow-up may further inform clinical practice regarding pre-pregnancy PVR.