Prognostic Value of NT-proBNP in Patients With Successful PCI for ACS and Normal Left Ventricular Ejection Fraction.

Background: Patients undergoing successful percutaneous coronary intervention (PCI) for acute coronary syndromes (ACS) with normal left ventricular ejection fraction (LVEF) are generally considered to have successful clinical outcomes; however, there are still significant differences in clinical outcomes among these patients. The aim of the study was to find a common indicator to predict the risk of major adverse cardiac and cerebrovascular events (MACCE) in this population.

Methods: A total of 3986 patients with ACS were divided into 4 groups based on the quartile (Q) values of peak N-Terminal pro-brain natriuretic peptide (NT-proBNP) measured during hospitalization. The incidence of MACCE was compared among Q1-Q4 groups during follow up. Multivariate Cox regression analysis was performed to identify independent prognostic factors of MACCE. Receiver operating characteristic (ROC) curve was generated to compare the area under the curve (AUC) for MACCE by adding NT-proBNP to the Thrombolysis in Myocardial Infarction (TIMI) risk score.

Results: NT-proBNP was significantly positively correlated with peak values of cardiac troponin I (cTnI) (r = 0.418), high-sensitivity C-reactive protein (hs-CRP) (r = 0.397) and left ventricular end-diastolic diameter (LVEDD) (r = 0.075) (P < 0.001). The risks of composite MACCE (5.6%, 9.1%, 13.0%, 20.1%, P < 0.001), all-cause death (1.0%, 2.5%, 4.1%, 8.4%, P < 0.001) and non-fatal myocardial infarction (2.0%, 3.4%, 4.8%, 6.2%, P < 0.001) were significantly higher in the higher Q groups. In multivariate analysis, the Q4 group displayed an independent 2.2-fold increase for MACCE compared to Q1 (HR: 2.16; 95%CI: 1.57-2.99; P < 0.001). Compared with TIMI risk score alone, TIMI+NT-proBNP showed improved AUCs: cardiovascular death (P = 0.0008), and heart failure requiring hospitalization (P = 0.0017).

Conclusions: In patients with ACS with successful PCI and normal LVEF, elevated NT-proBNP was significantly associated with poor clinical outcomes. These results suggest that NT-proBNP is a useful biomarker for prognosis and risk stratification in this population.