Cardiac and obstetric outcomes in pregnant women with heart disease: appraisal of the 2018 mWHO classification

Abstract

Objective: To appraise the application of the 2018 European Society of Cardiology-adapted modified WHO (mWHO) classification to pregnant women with heart disease managed at our maternal-fetal medicine referral centre and to assess whether the lack of a multidisciplinary Pregnancy Heart team has influenced their outcomes.

Methods: A retrospective cohort study including all pregnancies with heart disease managed at our centre between June 2011 and December 2020. Cardiac conditions were categorised in five classes according to the mWHO classification. An additional class, named X, was created for conditions not included in this classification. Outcomes were compared among all classes and factors potentially associated to cardiac complications were assessed.

Results: We identified 162 women with 197 pregnancies, for a prevalence of 0.7%. Thirty-eight (19.3%) gestations were included in class X. Caesarean section was performed in 64.9% pregnancies in class X, a rate similar to that of class II, II-III, and III/IV, and mostly for obstetric indications; in turn, it was more commonly performed for cardiology reasons in class II-III and III/IV. Cardiac complications occurred in 10.7%, with class X and II pregnancies showing the highest number of events (n=30.8% and 34.6%, respectively). Multiple gestation and urgent caesarean section associated with a 5-fold and 6.5-fold increase in complication rates.

Conclusions: Even in a maternal-fetal medicine referral centre, the lack of a multidisciplinary team approach to women with heart disease may negatively impact their outcomes.

Keywords: heart failure; metabolic syndrome; pregnancy; stroke.

Figure 1

Distribution of maternal HDs among the 2018 ESC-adapted mWHO classes. Pie chart shows the distribution of the 197 pregnancies (n=31 patients with >1 pregnancy during the study period) among the five classes of the 2018 ESC-adapted mWHO classification. Thirty-eight (19.3%) pregnancies could not be categorised according to this classification and were therefore included in a newly created class named X. ESC, European Society of Cardiology; HD, heart disease; mWHO, modified WHO.

Figure 2

Yearly distribution of maternal HDs during the study period with class X contribution. HD, heart disease.

Figure 3

Distribution of cardiac adverse events among 2018 ESC-adapted mWHO classes and class X. Pie chart shows the distribution of the 26 cardiac adverse events which occurred in 21 pregnancies (n=5 pregnancies with two events) during the study period among the five classes of the 2018 ESC-adapted mWHO classification and class X. ESC, European Society of Cardiology; mWHO, modified WHO.