Postpartum Readmissions Among Patients with Adult Congenital Heart Disease

Am J Obstet Gynecol MFM. 2024 Dec 16:101580. doi: 10.1016/j.ajogmf.2024.101580. Online ahead of print.

Abstract

Background: Given risks associated with CHD in the postpartum period, epidemiologic data identifying risk factors and timing of complications may be useful in improving postpartum care.

Objective: The objectives of this study were to determine timing of, risk factors for, and complications associated with 60-day postpartum readmissions following deliveries with maternal congenital heart disease (CHD).

Study design: The 2010-2020 Nationwide Readmissions Database was used for this retrospective cohort study. Postpartum readmissions occurring within 60-days of delivery hospitalization discharge were ascertained. Clinical, demographic, and hospital risk factors associated with postpartum readmission were analyzed with logistic regression models with unadjusted and adjusted odds ratios (aORs) as measures of association. Among patients with CHD the role of additional cardiac risk factors in likelihood of readmission was analyzed. Risks for adverse maternal outcomes during readmission including severe maternal morbidity (SMM), cardiac SMM, and a critical care composite were analyzed.

Results: Of an estimated 40,780,439 delivery hospitalizations, 35,242 had an associated CHD diagnosis (8.6 per 10,000) including 2,279 (6.5%) for complex CHD and 32,963 (93.5%) for non-complex CHD. The proportion of deliveries with a maternal CHD diagnosis increased significantly from 6.7 per 10,000 in 2010 to 11.8 in 2020. Overall risk for 60-day postpartum readmission was 1.6% among women without CHD and 3.1% among women with CHD (p<0.01). Among women with CHD, 36.0% of 60-day postpartum readmissions occurred 1-5 days after discharge, 18.0% 5-10 days after discharge, and 14.5% 10-20 days after discharge. In adjusted models for the entire population, CHD retained a significant association with 60-day postpartum readmission (aOR 1.73, 95% CI 1.55, 1.94). When the cohort was restricted to deliveries with CHD, adjusted analyses demonstrate an increased odds associated with additional cardiac risk factors (congestive heart failure, aOR 1.72, 95% CI 1.13-2.62; arrhythmia, aOR 1.68, 95% CI 1.27-2.21; pulmonary circulation disorders, aOR 1.57, 95% CI 1.10-2.24; and chronic hypertension, aOR 1.88, 95% CI 1.26-2.80), hypertensive disorders of pregnancy (aOR 1.97, 95% CI 1.49-2.61) and cesarean delivery (primary aOR 1.82, 95% CI 1.39-2.38; repeat cesarean: aOR 1.91, 95% CI 1.42-2.55). The risk of adverse outcomes during readmissions was higher for women with CHD compared to those without: SMM (23.8% versus 16.1%, p<0.01), cardiac SMM (9.6% versus 4.9%, p<0.01), and a critical care composite (3.1% versus 1.8%, p<0.01).

Conclusion: Deliveries with CHD were associated with increased odds of postpartum readmission and complications during readmissions. The majority of readmissions occurred soon after delivery discharge. Among patients with CHD, risk for readmission was higher in the setting of additional cardiac risk factors, hypertensive disorders of pregnancy, and cesarean delivery.

Keywords: Congenital heart disease; maternal outcomes; postpartum readmissions; severe maternal morbidity.