Prognostic Value of the Percentage of Neutrophils on Admission in Patients with ST-elevated Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

Background and Aims: An elevated neutrophil count or neutrophil/lymphocyte ratio on admission has been reported to be an independent predictor of adverse cardiac events in patients with acute coronary syndrome (ACS). The relationship between the percentage of neutrophils (N%) at the time of admission and the long-term outcomes in patients with ST-segment elevated myocardial infarction (STEMI) who have undergone primary percutaneous coronary intervention (PCI) remains unclear. The aim of this study was to investigate the usefulness of the admission N% in predicting long-term mortality in patients with STEMI who were undergoing primary PCI. Methods: We evaluated 701 consecutive patients admitted to nine medical institutions in northwest China within 24 h after symptom onset from January 1, 2009-December 31, 2011. Using a receiver-operating characteristic analysis, N% ≥82.1% was the best predictor of long-term mortality. Patients were divided into two groups according to this criterion. Mean follow-up time was 39.03 months. Results: The long-term all-cause mortality rate was significantly higher in patients with a high N% level (7.17 vs. 3.11%, p = 0.015) as was the rate of cardiac mortality (6.48 vs. 2.59%, p = 0.013). In a multivariate logistic analysis, a high N% level was an independent predictor of long-term all-cause mortality (odds ratio 2.59, 95% confidence interval 1.21-5.53, p = 0.002) and long-term cardiac mortality (odds ratio 2.79, 95% confidence interval 1.24-6.28, p = 0.013). Conclusions: A high N% level on admission is an independent predictor of long-term mortality in STEMI patients undergoing primary PCI.