(607) Cardiac disease and risk of hypertensive disorders of pregnancy

Objective: Cardiovascular disease affects 1-4% of US pregnancies and is the leading cause of pregnancy related deaths. There are limited data on rates of hypertensive disorders of pregnancy (HDP) in this population. ACOG and USPSTF guidelines for aspirin (ASA) use for reduction of preeclampsia (PEC) do not include cardiac disease in the high or moderate risk categories. Our objective was to determine if cardiovascular disease is a risk factor for developing HDP.

Study Design: This was a retrospective cohort study of pregnancies complicated by maternal cardiac disease at a single academic center between 2018 and 2022. Patients with cardiac disease (congenital or acquired) who delivered after 20 weeks were included. For patients with multiple pregnancies during the timeframe, only the first pregnancy was included. Patient demographics and pregnancy outcomes were recorded. The primary outcome was development of HDP. Secondary outcomes were correlation of HDP with presence of one high or two moderate risk factors based on ACOG guidelines for ASA use and severity of cardiac disease based on modified World Health Organization (mWHO) risk class.

Results: 115 patients were included. Demographic and outcomes are shown in Table 1. 18 (15.7%) patients developed HDP and 71 patients (61.7%) were on ASA. Among the 18 patients with HDP, 55% developed PEC with severe features and 44% developed PEC post-partum. HDP was associated with multiple gestations (p < 0.01), age (p=0.04) and the combination of one high risk or two moderate risk factors for PEC (p=0.03). mWHO class was not associated with development of HDP (p=0.86).

Conclusion: It has not been established if cardiac disease in pregnancy is an independent risk factor for developing PEC. Our study reveals high rates of HDP in this cohort (15.7% in our population compared to CDC rate of 4% of US pregnancies), even in the setting of ASA use and regardless of mWHO risk class. While more research is needed, based on our data it would be reasonable to offer patients with cardiac disease ASA for prevention of PEC.