Maternal cardiovascular events during childbirth among women with congenital heart disease

Abstract

Objectives: To define the epidemiology of adverse cardiovascular events among women with congenital heart disease (CHD) hospitalised for childbirth in the USA.

Design and setting: The 1998-2007 Nationwide Inpatient Sample, an administrative dataset representative of overall US hospital admissions, was used to identify hospitalisations for delivery.

Main outcome measures: Logistic regression was used to estimate ORs for cardiovascular outcomes (arrhythmia, heart failure, cerebrovascular accident, embolism, death or a combined outcome) for women with and without CHD. Covariates included age, number of medical comorbidities, pulmonary hypertension, hospital teaching status, insurance status and method of delivery.

Results: Annual deliveries for women with CHD increased 34.9% from 1998 to 2007 compared with an increase of 21.3% in the general population. Women with CHD were more likely to sustain a cardiovascular event (4042/100,000 vs 278/100,000 deliveries, univariate OR 15.1, 95% CI 13.1 to 17.4, multivariable OR 8.4, 95% CI 7.0 to 10.0). Arrhythmia, the most common cardiovascular event, was more frequent among women with CHD (2637/100,000 vs 210/100,000, univariate OR 12.9, 95% CI 10.9 to 15.3, multivariable OR 8.3, 95% CI 6.7 to 10.1). Death occurred in 150/100,000 patients with CHD compared with 8.2/100,000 patients without CHD (multivariable OR 6.7, 95% CI 2.9 to 15.4). Complex CHD was associated with greater odds of having an adverse cardiovascular event than simple CHD (8158/100,000 vs 3166/100,000, multivariable OR 2.0, 95% CI 1.4 to 3.0).

Conclusions: Maternal CHD is associated with a markedly increased risk of adverse cardiovascular events and death during admission for delivery.