Usefulness of B-type natriuretic peptide to predict outcome of patients treated by transcatheter aortic valve implantation

Abstract

B-type natriuretic peptide (BNP) has been shown to predict outcomes after conventional aortic valve replacement. The aim of the present study was to investigate whether BNP also predicts the outcomes after transcatheter aortic valve implantation (TAVI). A total of 58 patients (36 men, age 84 ± 5 years) underwent TAVI in our institution for severe aortic stenosis (aortic valve area 0.6 ± 0.1 cm², mean gradient 41 ± 15 mm Hg) at high risk of surgery (logistic European System for Cardiac Operative Risk Evaluation 34 ± 17%). BNP was measured before and 24 hours after TAVI. The 30-day survival rate was 91%. Although the baseline clinical and hemodynamic characteristics were similar among the 30-day survivors (n = 53) and nonsurvivors (n = 5), the BNP levels were significantly lower in the 30-day survivors, at both baseline (463 ± 265 vs 1,067 ± 655 pg/ml; p = 0.005) and 24 hours after TAVI (488 ± 238 vs 1,632 ± 1,028 pg/ml; p <0.0001). The BNP levels were significantly greater in patients experiencing one major adverse event at 30 days. On multivariate analysis, only BNP levels (baseline value and change at 24 hours) were independent predictors of 30-day survival. Kaplan-Meier analysis showed that 30-day survival was significantly lower in patients with than in those without both a baseline BNP level >428 mg/dl (p = 0.04) and a significant BNP increase of >170 pg/ml at 24 hours after TAVI (p = 0.001). In conclusion, BNP is a strong predictor of 30-day outcomes after transcatheter aortic valve implantation, at both baseline and 24 hours after the procedure.