N-terminal pro-B-type natriuretic peptide is associated with adverse short-term clinical outcomes in patients with acute ST-elevation myocardial infarction underwent primary percutaneous coronary intervention

Background: Increased level of N-terminal pro-B type natriuretic peptide (NT-proBNP) is known to be associated with adverse outcome in patients with acute coronary syndrome. We evaluated early outcomes of patients with acute ST-elevated myocardial infarction (STEMI) according to the level of NT-proBNP as a substudy of Korean Acute Myocardial Infarction Registry (KAMIR). Methods: Study population consisted of 1052 consecutive patients (mean 61.3 ± 12.8 years old, male 73.2%) with STEMI of onset < 12 h who underwent primary percutaneous coronary intervention (PCI) and who had baseline NT-proBNP level by electrochemiluminescence immnunoassay (ECLIA, NT-proBNP kit, Roche Diagnostics, Mannheim, Germany). The study subjects were divided into two groups according to the level of serum NT-proBNP. Results: Patients with NT-proBNP level > 991 pg/mL (n = 329, 57.1% male) had lower left ventricle ejection fraction (LVEF) (47.8 ± 11.8% vs. 53.0 ± 10.8%, p < 0.001), needed longer intensive care (3.7 ± 3.6 days vs. 2.8 ± 2.4 days, p < 0.001) and had higher in-hospital mortality (1.3% vs. 7.4%, p < 0.001) than those with NT-proBNP level ≤ 991 pg/mL (n = 723, 80.5% male). Multiple logistic regression analysis revealed that the independent predictors of in-hospital mortality were LVEF < 45% (OR 5.43, 95% CI 1.71 to 17.29, p = 0.004), elevated NT-proBNP (> 991 pg/mL) (OR 3.70, 95% CI 1.14 to 12.03, p = 0.030), old age (≥ 70 years) (OR 4.71, 95% CI 1.43 to 15.52, p = 0.011), advanced Killip class (> 1) (OR 4.96, 95% CI 1.58 to 15.53, p = 0.006), male gender (OR 5.67, 95% CI 1.45 to 22.21, p = 0.013) and TIMI flow 0 before PCI (OR 5.04, 95% CI 1.08 to 23.41, p = 0.039). Conclusions: This study suggests that baseline NT-proBNP level is associated with short term mortality in patients with STEMI underwent primary PCI.