28 Brain natriuretic peptide monitoring in preeclampsia

Abstract

Introduction Preeclampsia causes multiple organ damage and 3% of women with severe preeclampsia cause heart failure. Although trans-thoracic echocardiography is essential for the evaluation of cardiac function, it is practically difficult to use echocardiography for the screening of heart failure in preeclamptic women. Brain natriuretic peptide (BNP) is a useful serum maker for the evaluation of cardiac function, and BNP monitoring has a potential to improve management of cardiac dysfunction; however, BNP levels are affected by age, sex, kidney function, and body mass index (BMI). Objectives The aim of this study is to examine the BNP levels in preeclamptic women and confounding factors which affect BNP levels. Methods This was a single-center prospective study from 2013 to 2015. We enrolled 137 preeclamptic women and 773 normal pregnant women. Twin pregnant women were excluded. Serum BNP was examined before delivery: after the diagnosis of preeclampsia in preeclamptic women and at late pregnancy (35–37th gestational week) in normal pregnant women and after delivery: within 4 days postpartum. Echocardiography was also performed at the same timing of BNP monitoring in preeclamptic patients. Baseline characteristics, pre-delivery BNP, and post-delivery BNP between normal pregnant and preeclamptic women were analyzed with independent t-test. Multiple regression analysis was conducted to examine the confounding factors of BNP levels in eclamptic women, and age, pre-pregnancy BMI, serum creatinine, systolic blood pressure, diastolic blood pressure, ejection fraction (EF), and early transmitral velocity/early diastolic velocity of the mitral annulus (E/e’) were used as independent variables. In addition, blood loss at delivery was also included in the analysis of post-delivery BNP. Results Age of normal and preeclamptic women were 34.1 ± 5.2 and 33.6 ± 5.8, p = 0.27. BMI were 21.7 ± 4.0 and 23.1 ± 5.3, p ± 13.7 and 82.9 ± 103.6, p ± 35.8 and 63.1 ± 71.8, p Conclusions BNP levels deteriorated after delivery in normal pregnant women while BNP levels improved after delivery in preeclamptic women. Delivery causes a stress on maternal heart, but recovery from preeclampsia had bigger impact on BNP levels. Although BNP levels reflected maternal cardiac function, the effect of pre-pregnancy BMI, kidney function, blood pressure, and blood loss at delivery should be considered when using BNP monitoring in preeclamptic women. Besides, pre-pregnancy BMI was negatively related with BNP levels although obesity is a risk factor of heart failure. Download : Download high-res image (241KB) Download : Download full-size image