Cardiac remodelling during pregnancy in women with congenital heart disease and systemic left ventricle.

Aims: Women with congenital heart disease (CHD) are at risk of pregnancy-related adverse outcomes (PRAO). The purpose of this study was to assess temporal changes in cardiac structure and function (cardiac remodelling) during pregnancy, and the association with PRAO in women with CHD.

Methods and results: Retrospective study of pregnant women with CHD and serial echocardiograms (2003-2021). Cardiac structure and function were assessed at pre-specified time points: prepregnancy, early pregnancy, late pregnancy, and postnatal period. PRAO was defined as the composite of maternal cardiovascular, obstetric, and neonatal complications. The study comprised 81 women with CHD (age, 29 ± 5 years). Compared to the baseline echocardiogram, there was a relative increase in right ventricular systolic pressure (RVSP) (relative change 13 ± 5%, P < 0.001, in early pregnancy; and 18 ± 5%, P < 0.001, in late pregnancy). There was a relative decrease in right ventricle free wall strain (RVFWS) (relative change -11 ± 3%, P < 0.001, in late pregnancy; and -11 ± 4%, P = 0.003, in postnatal period), and a relative decrease in RVFWS/RVSP (relative change, -10 ± 5%, P = 0.02 in early pregnancy, -26 ± 7%, P < 0.001, in late pregnancy, and -14 ± 5%, P < 0.001, in postnatal period). Baseline right ventricular to pulmonary arterial (RV-PA) coupling, and temporal change in RV-PA coupling were associated with PRAO, after adjustment for maternal age and severity of cardiovascular disease.

Conclusion: Women with CHD had a temporal decrease in RV systolic function and RV-PA coupling, and these changes were associated with PRAO. Further studies are required to delineate the aetiology of deterioration in RV-PA coupling during pregnancy, and the long-term implications of right heart dysfunction observed in the postnatal period.