History of heart transplant tied to worse pregnancy outcome

TOPLINE:

Almost one-quarter of pregnant women who have had a heart transplant (HT) will experience severe maternal morbidity (SMM) during their hospital stay for delivery, and they have sevenfold greater risk for preterm birth than do other pregnant women, results of a large study with a nationwide sample suggest.

METHODOLOGY:

• The retrospective cohort study included 2010-2020 information from the Nationwide Readmissions Database (NRD), a large, all-payer administrative dataset that allows for tracking of patient hospital readmissions in the same U.S. state within the same calendar year and includes patient demographics, hospital characteristics, diagnosis and procedure codes (including for cardiac transplants), length of stay, and discharge disposition.
• The primary outcome was nontransfusion SMM which, among other conditions, included acute myocardial infarction, aortic aneurysm, acute renal failure, adult respiratory distress syndrome, amniotic fluid embolism, cardiac arrest/ventricular fibrillation, and heart failure/arrest, during the delivery hospitalization.
• Additional outcomes included rates of all SMMs (including transfusion), a composite cardiovascular SMM (cSMM) outcome that included acute myocardial infarction, aortic aneurysm, cardiac arrest/ventricular fibrillation, cardioversion, and acute heart failure, preterm birth, and readmission rates.

TAKEAWAY:

• From 2010 to 2020, there were 19,399,521 hospital deliveries, of which, 105 were in HT recipients.
• In unadjusted comparisons, rates of all outcomes were higher in HT, compared with non-HT delivery hospitalizations, and after adjusting for age, demographic and facility characteristics, comorbid conditions, and calendar year, HT recipients continued to have higher odds of adverse maternal outcomes. For example, HT recipients had higher rates of nontransfusion SMM (adjusted odds ratio, 28.12; 95% confidence interval, 15.65-50.53), all SMM (aOR, 15.73; 95% CI, 9.17-27.00), cSMM (aOR, 37.7; 95% CI, 17.39-82.01), and preterm birth (aOR, 7.15; 95%, CI 4.75-10.77).
• HT recipients also had longer hospital stays and higher rates of cesarean delivery, although the authors noted that it’s unclear whether this increase was caused by the HT or complications of pregnancy because data were unavailable regarding indication for cesareans.
• Patients with HT were also at increased risk for hospital readmission within the first year after delivery, particularly within the first 6 months, including for HT-related complications, a finding that supports guidelines recommending an initial postpartum visit within 7-14 days of discharge for patients with cardiac conditions, write the authors.

IN PRACTICE:

The findings demonstrate the importance of counseling HT patients at early gestational ages “to provide information about anticipated risks in pregnancy and the postpartum period to allow patients the opportunity to make informed choices regarding their reproductive options,” the authors conclude.

SOURCE:

The study was conducted by Amanda M. Craig, MD, division of maternal fetal medicine, department of obstetrics and gynecology, Duke University Medical Center, Durham, N.C., and colleagues. It was published online in JACC Heart Failure.

LIMITATIONS:

Relying on diagnosis and procedure codes in administrative datasets like NRD may result in underestimation of outcomes. In this study, outcomes were limited to delivery hospitalizations, which may underestimate the true incidence of complications or fail to include pregnancies that didn’t end in a delivery, including pregnancy terminations or spontaneous abortions. Information related to race, ethnicity, hospital regions, and cause of death are not captured in the NRD dataset.

DISCLOSURES:

The authors have no relevant conflicts of interest.

A version of this article first appeared on Medscape.com.