Chronic Terbutaline Therapy and Peripartum Cardiomyopathy: A Case-Control Study

Abstract

Objective: A previous case report (1) described 15 women with peripartum cardiomyopathy documented by clinical and ECHO criteria, 4 of whom had received terbutaline long term (range 9.5-53 days, mean 4.2 ± 2.6 weeks) for premature labor. To further explore the significance of this observation a case-control study was designed specifically inquiring whether long-term 3-Mimetic therapy of at least 9 days duration for preterm contractions is associated with subsequent development of peripartum cardiomyopathy.

Methods: Controls for the 15 cardiomyopathic patients were chosen by computer-generated random patient unit number selection from all deliveries occurring in the period 1985-1991. Medical records were reviewed to determine exposure to terbutaline and other tocolytics, as well as potentially confounding factors. A logistic regression analysis of the data was performed and adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated for the covariates.

Main Outcome Measure: Quantitation of exposure to (3-mimetic agents in peripartum cardiomyopathy patients and patients without this disease.

Results: While 4 (26.7%) of the original 15 cases had received long-term terbutaline therapy, only 3 (5.0%) of 60 controls did. The potentially confounding variables were smoking and maternal age, but even when these were controlled, terbutaline therapy remained significantly associated with the development of peripartum cardiomyopathy, OR 6.91 (1.30-36.85), P = 0.02.

Conclusion: These data suggest a relationship between long-term terbutaline therapy for preterm labor and subsequent development of peripartum cardiomyopathy.

Key Words:

• β-Mimetic complication
• Peripartum cardiomyopathy
• Terbutaline complication
• Tocolytic complication