Brain natriuretic peptide as a marker for heart disease in pregnancy

Abstract

ETOI GARRISON (F), JUDITH HIBBARD, LAURA STUDEE, DEIDRA FONTANA, SARAH KILPATRICK, JOAN BRILLER, University of Illinois at Chicago, Obstetrics and Gynecology, Chicago, Illinois, University of Illinois at Chicago, Cardiology, Chicago, Illinois OBJECTIVE: Brain Natriuretic Peptide (BNP) is secreted by the heart in response to ventricular stretch and volume overload. While BNP has been demonstrated to be a sensitive marker for left ventricular dysfunction (LVD) in the nonpregnant population, little is known of its utility in pregnancy. We evaluated the association between BNP and LVD during pregnancy in 39 women referred to a cardiology practice from 2003-2005. STUDY DESIGN: All women presented during pregnancy or postpartum with clinical findings suggestive of decompensated cardiac disease, including dyspnea, pulmonary edema, tachycardia, chest pain, and history of cardiac disease.Echocardiography andBNPwere obtained in all patients for clinical indications. Ejection fraction was determined by an experienced echocardiographer and categorized as normal, mild (EF=40-50%), moderate (EF=30-40%), or severely depressed (EF! 30%). Differences between continuous variables were calculated using mean G S. E. Categorical data was analyzed by Chi Square or Fisher’s Exact Test, p!0.05 was considered significant. Regression analysis was used to determine the association between variables. RESULTS: There was a significant association between mild to severe LVD and BNP level [R 0.538, p!0.005]. BNP O100 pg/ml had a sensitivity of 72.7%, specificity of 32.1%, positive predictive value of 47%, and a negative predictive value of 86% for mild to severe LVD. Those diagnosed with acute cardiac decompensation (ACD) (n=9) had significantly higher mean BNP on initial presentation (730.5 pg/ml G 53.7) compared to those without (81.5 pg/ml G 14.7, p!0.05). There was no significant association between mild to severe LVD and BNP O 100 pg/ml in those patients without ACD [OR 1.50, 95% CI 0.14-14.9]. Causes of acute cardiac decompensation included peripartum cardiomyopathy (n= 5), hypertrophic cardiomyopathy (n=2), valvular heart disease (n=1), and non ST elevation MI (n=1). CONCLUSION: BNP may be useful in identifying acute cardiac decompensation in symptomatic women during pregnancy.