Pregnant women with congenital heart disease may have higher risk of poor outcomes during delivery

Pregnant women with congenital heart disease (CHD) had an increased risk of congestive heart failure, atrial arrhythmias and fetal growth restrictions during delivery, according to a retrospective database analysis.

Lead researcher Robert M. Hayward, MD, of the University of California, San Francisco, and colleagues published their results online in JAMA Cardiology on April 12.

The researchers noted that more than one million adults in the U.S. are living with CHD and that most people with the condition survive to adulthood.

For this study, they evaluated more than 3.6 million delivery admissions from the Health Care Utilization and Cost Project’s California state inpatient database from Jan. 1, 2005 through Dec. 31, 2011.

From that data, the researchers identified 3,189 women with noncomplex CHDand 262 women with complex CHD. The mean ages were 28.6 years old and 26.5 years old, respectively. The mean age of the remaining women was 28.3 years old.

Women with CHD were more likely to have a history of congestive heart failure, undergo a caesarean delivery, stay longer in the hospital and have preeclampsia or eclampsia.

The researchers noted that fewer than 0.5 percent of women with noncomplex or complex CHD had incident congestive heart failure, atrial arrhythmias, ventricular arrhythmias and maternal mortality. Still, the odds of those outcomes were much higher for women with CHD compared with those without the condition.

After multivariate adjustment, the odds ratios for incident congestive heart failure were 9.7 for women with noncomplex CHD and 56.6 for women with complex CHD. The odds ratios for atrial arrhythmias were 8.2 and 31.8, respectively, while the odds ratios for fetal growth restriction were 1.6 and 3.5, respectively.

Meanwhile, the odds ratio for hospital readmission in both CHD groups was 3.6. In addition, complex CHD was associated with greater adjusted odds of serious ventricular arrhythmias and maternal in-hospital mortality.

The study had a few potential limitations, according to the researchers, including that congenital heart defects could have been undercoded. In addition, they could not link the medical records of mothers and neonates to determine the infants’ long-term health outcomes and they did not examine women who chose not to become pregnant or who did not carry pregnancies to term, which they noted could account for approximately 20 percent of pregnancies among women with CHD. Further, the did not have information on the intensity or quality of care before and after delivery and did not have data on women who moved to another state or died outside the hospital for their follow-up analysis.

“Incident maternal [congestive heart failure], arrhythmias, and mortality were uncommon in all groups of women, but CHD was significantly associated with incident [congenital heart failure], atrial arrhythmias, fetal growth restriction, and hospital readmission,” the researchers wrote. “Complex CHD was a significant predictor of ventricular arrhythmias and maternal in-hospital mortality. These results may guide monitoring decisions and risk assessment for pregnant women with CHD at the time of delivery. Given the higher rate of cardiac and obstetrical complications, pregnant women with CHD should be treated in a center with expertise in adult CHD.”