Pregnancy outcomes in women with mechanical prosthetic heart valves: a
retrospective case series analysis
Abstract
Introduction: Pregnant women with mechanical prosthetic heart valves
(MPHV) are reportedly at high risk of mortality and morbidity. We aimed
to compare outcomes at our specialist centre with national data, and
whether anticoagulation regimes influenced outcome. Methods: We
conducted a retrospective cross-sectional study of all pregnant women
with MPHV managed by our service between 2003-2021. Maternal and fetal
outcomes and anticoagulation data were collected. Summary statistics and
comparative analysis with results from the national UK-wide dataset were
compiled. Results: A total of 50 pregnancies in 23 women were
identified. Patients with complex valve replacements were common, with
34.8% of pregnancies involving management of dual MPHV. Maternal
mortality was zero (95% CI: 0-7.1). Serious maternal and obstetric
complications occurred in only 7 pregnancies (14.0%; 95% CI:
7.0-26.2%), including only two valve thromboses (4%). Live births
followed 31 of the pregnancies (62%), compared with a national baseline
of ~75%. Low molecular weight heparin was the most
commonly used anticoagulant during pregnancy (84%), but no single
anticoagulation regime was found to be universally optimal. Concomitant
low-dose aspirin was given to those with dual or systemic mechanical
atrioventricular valve replacement. Discussion: Our study is the largest
single centre report on maternal outcome for women with MPHV. We share
how comprehensive, multidisciplinary planning may significantly reduce
mortality and morbidity for our patients. Anticoagulation management
should be individualised according to patient risk profile. With
appropriate peripartum care, risk for women with MPHV considering
pregnancy may be lower than previously reported