Cardiac surgery during pregnancy: what is the optimal timing of intervention? A meta-analysis of individual patient data

Abstract Background Cardiac disease can manifest or worsen during pregnancy and some cases urges cardiac surgery. According to current guidelines, the second trimester is supposed to be the optimal time frame. However, evidence for this recommendation is poor. Objective We evaluate whether an optimal period to undergo cardiac surgery during pregnancy can be identified, focusing on both maternal and foetal outcomes. Methods All studies published in Medline up to February 8th, 2018 on maternal and/or foetal outcome of cardiac surgery during pregnancy that included individual patient data were identified. Three groups were analysed: all identified patients (total population), patients who underwent caesarean section (CS) prior to cardiac surgery (subgroup A) and patients who underwent cardiac surgery with the foetus in utero (subgroup B). For the total population and subgroup B, logistic regression analysis was performed to find predictors of maternal and foetal outcome. Results We identified 142 studies including 328 patients of which 114 underwent CS prior to cardiac surgery (subgroup A). Maternal mortality in the total population was 5.2% and did not differ significantly among trimester (p=0.634). Foetal mortality in the total population was lowest in the third trimester (9.4%, p<0.01) and CS prior to surgery significantly reduced risk of foetal mortality in a multivariate model (OR 0.09, CI 0.02–0.35). Subgroup analysis showed foetal mortality of 7.0% in subgroup A and 33.6% in subgroup B (p<0.01). Trimester was not identified as a significant predictor for foetal and/or maternal mortality in subgroup B. See table 1. Conclusion Maternal mortality of cardiac surgery during pregnancy is not significantly influenced by trimester. Foetal mortality after maternal cardiac surgery is very high. When the fetus is viable, CS prior to cardiac surgery should be considered in the third trimester. If not feasible or safe to postpone surgery, trimester stage should not delay cardiac surgery. Funding Acknowledgement Type of funding source: None