The neutrophil-to-lymphocyte ratio, as an emerging marker, is an important indicator predicting spontaneous reperfusion and clinical prognosis in patients with ST-segment elevation myocardial infarction

BackgroundNeutrophil to lymphocyte ratio (NLR) has emerged as a new inflammation marker, which plays a major role in plaque instability, rupture, and erosion, and facilitates its progression, leading to acute myocardial infarction. The study aims to explore the role of NLR in predicting spontaneous reperfusion (SR) and prognosis in patients with ST-segment elevation myocardial infarction (STEMI). MethodsThis was a retrospective analysis including 506 STEMI patients undergoing primary percutaneous coronary intervention treatment, who were divided into two groups according to the thrombolysis in myocardial infarction (TIMI) flow: SR group (69 patients, initial TIMI flow 3) and No-SR group (437 patients, initial TIMI flow 0-2). ResultsThe incidence of SR was 13.6%. SR group was associated with a remarkably lower level of NLR [5.14 (2.97, 7.02) vs. 8.03 (4.54, 10.92), P<0.001], more proportions of final TIMI 3 flow (98.6% vs. 91.5%, P < 0.05), lower incidence of congestive heart failure (8.7% vs. 18.5%, P < 0.05), and significantly better outcomes. Using multivariate logistic regression analysis, NLR (OR: 0.799, 95% CI: 0.730-0.874, P < 0.001) and fasting blood glucose were the independent predictors of SR. On multivariate Cox regression analysis, NLR (HR: 1.035, 95% CI: 1.001-1.071, P < 0.05) was the independent predictor of MACEs during follow-up. ConclusionsNLR had the ability in predicting SR in STEMI patients and SR flow was associated with a favorable outcome. We also revealed an association between NLR and increased risk of MACEs during follow-up. Clinical PerspectiveO_ST_ABSWhat Is New?C_ST_ABSO_LIThe incidence of spontaneous reperfusion was 13.6%. Patients with spontaneous reperfusion had a remarkably low level of NLR [5.14 (2.97, 7.02) versus 8.03 (4.54, 10.92), P<0.001], more proportions of final TIMI 3 flow (98.6% versus 91.5%, P < 0.05), lower incidence of congestive heart failure (8.7% versus 18.5%, P < 0.05), and favorable outcomes. C_LIO_LINLR was not only an independent predictor of spontaneous reperfusion, but also was the independent predictor of major adverse cardiac events during follow-up (HR: 1.035, 95% CI: 1.001-1.071, P < 0.05) in patients with ST-segment elevation myocardial infarction. C_LI What Are the Clinical Implications?O_LIThe level of neutrophil to lymphocyte ratio in patients with ST-segment elevation myocardial infarction is associated with low occurrence of spontaneous reperfusion and adverse outcomes, although, the patients received primary percutaneous coronary intervention. C_LIO_LINeutrophil to lymphocyte ratio the plays a major role in the risk classification of patients with ST-segment elevation myocardial infarction. C_LI