Serum N-Terminal Pro-B-Type Natriuretic Peptide Levels at the Time of Hospital Admission Predict of Microvascular Obstructions after Primary Percutaneous Coronary Intervention for Acute ST-Segment Elevation Myocardial Infarction

BACKGROUND: Significant microvascular obstruction (MVO) during primary percutaneous coronary intervention (PCI) may suggest severe myocardial damage. The predictive value of N-terminal pro-B-type natriuretic peptide levels (NT-proBNP) for MVO has not been previously evaluated. HYPOTHESIS: The purpose of the study was to determine whether NT-proBNP levels measured upon hospital admission of ST-segment elevation myocardial infarction (STEMI) patients receiving primary PCI have predictive value for MVO. METHODS: NT-proBNP levels were obtained upon admission to the emergency department, for 41 acute STEMI patients. Cardiac contrast-enhanced magnetic resonance imaging (CE-MRI) was performed within 4 days after PCI. The optimal cut-off value to predict grade 3 MVO was determined using a receiver operating characteristic (ROC) curve. Multivariate regression analysis was performed to determine predictors for grade 3 MVO. RESULTS: MVO grade correlated with left ventricular ejection fraction (LVEF; r =-0.383, P = 0.013), peak serum creatine kinase MB iso-enzyme (CK-MB; r = 0.470, P = 0.002), and NT-proBNP levels (r = 0.357, P = 0.022). The optimal cut-off value to predict grade 3 MVO was an NT-proBNP level of ≥80 pg/mL. Multivariate regression analysis, including LVEF, peak CK-MB, and an NT-proBNP ≥80 pg/mL revealed that only an NT-proBNP ≥80 pg/mL was an independent factor related to grade 3 MVO. CONCLUSION: NT-proBNP levels upon hospital admission have a predictive value for MVOs. Further study is needed to determine if protective treatment strategies are warranted in STEMI patients with high NT-proBNP levels at presentation.