B-Type Natriuretic Peptide as a Predictor of Postoperative Heart Failure After Aortic Valve Replacement

Abstract

B-type natriuretic peptide (BNP) has been established as a biomarker for heart failure. The objective was to evaluate BNP measured on arrival in the intensive care unit (ICU) as a predictor for heart failure defined as need for inotropic support or IABP beyond 24 hours postoperatively after aortic valve replacement. A prospective, observational study. A cardiothoracic surgery unit at a tertiary level hospital. One hundred sixty-one patients undergoing aortic valve replacement. Two levels of BNP were evaluated: the median (BNP >133 pg/mL) and a cutoff (BNP >82 pg/mL) based on receiver-operating characteristic (ROC) analysis. Uni- and multivariate analysis were performed to identify predictors of postoperative heart failure. Patients with postoperative heart failure (n = 37) showed a more than 10-fold increase in 30-day mortality (8.1%, 3/37) compared with patients without postoperative heart failure (0.8%, 1/124) (p = 0.038). Elevated postoperative BNP levels were identified as an independent predictor of postoperative heart failure: BNP >82 pg/mL (p = 0.004) and BNP >133 pg/mL (p = 0.013). The area under the ROC curve for BNP as a predictor of postoperative heart failure was 0.69. Postoperative heart failure after aortic valve replacement is still a very serious condition with increased early mortality. The results of the present study suggest that an elevated BNP level on arrival in the ICU is an independent predictor of postoperative heart failure after aortic valve replacement. In the authors' opinion, an increased BNP level on arrival in the ICU may support early diagnosis and allow optimal management of heart failure after aortic valve replacement.