Prognostic association of plasma NT-proBNP levels in patients with microvascular angina -A report from the international cohort study by COVADIS.

Abstract

In this international prospective cohort study of MVA by the Coronary Vasomotor Disorders International Study (COVADIS) group, we examined the association between plasma NT-proBNP levels and the incidence of major adverse cardiovascular events (MACE), including cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, and hospitalization due to heart failure or unstable angina. We examined a total of 226 MVA patients (M/F 66/160, 61.9±10.2 [SD] yrs.) with both plasma NT-proBNP levels and echocardiography data available at the time of enrolment. The median level of NT-proBNP level was 94pg/ml, while mean left ventricular ejection fraction was 69.2±10.9% and E/e' 10.7±5.2. During follow-up period of a median of 365days (IQR 365-482), 29 MACEs occurred. Receiver-operating characteristics curve analysis identified plasma NT-proBNP level of 78pg/ml as the optimal cut-off value. Multivariable logistic regression analysis revealed that plasma NT-proBNP level≥78pg/ml significantly correlated with the incidence of MACE (odds ratio (OR) [95% confidence interval (CI)] 3.11[1.14-8.49], P=0.001). Accordingly, Kaplan-Meier survival analysis showed a significantly worse prognosis in the group with NT-proBNP≥78 (log-rank test, P<0.03). Finally, a significant positive correlation was observed between plasma NT-proBNP levels and E/e' (R=0.445, P<0.0001). These results indicate that plasma NT-proBNP levels may represent a novel prognostic biomarker for MVA patients.