Determination of the relationship of neutrophil to lymphocyte ratio with TIMI risk criteria in patients with STEMI under primary PCI

Abstract

Cardiovascular diseases are the leading cause of death in patients. STEMI accounts for most cases and requires a suitable diagnostic and treatment strategy. In countries with limited medical resources, it is challenging to implement all treatment guidelines for all patients and therefore patients who benefit the most from interventional treatments should be selected from other patients. One of the risk estimation tools is the thrombolysis risk score in myocardial infarction or TIMI risk score, which is used to evaluate the need for reperfusion treatment in STEMI patients. In patients with STEMI, inflammation plays an essential role in the pathogenesis and progression of atherosclerosis. It is involved in events such as endothelial lesions, plaque formation, and rupture. Among white blood cells and related subtypes, NLR has a higher estimation power to determine mortality in patients with acute coronary syndrome or ACS. The current study investigates the relationship between the neutrophil-to-lymphocyte ratio and the TIMI risk measure in patients with STEMI who underwent primary PCI. Materials and Methods: In this cross-sectional study, 532 patients who suffered from STEMI and underwent primary PCI during the last 5 years were enrolled. Determining STEMI in patients was based on the criteria of the American College and Society of Cardiology. Complete physical and clinical examinations as well as coronary artery examinations have been performed for all patients. The TIMI score was considered between 0 and 14. Then the patients were divided into the low-risk group (TIMI less than and equal to 4) and the high-risk group (TIMI greater than 4). The main aim of the current study is to evaluate the diagnostic value of the neutrophil-to-lymphocyte ratio (NLR) in predicting mortality in patients with STEMI who have undergone primary PCI. Results: 532 patients were included in the study, 79.9% of them were male and their average age was 63.73 years with a range of 20 to 90 years. The most common underlying disease in the patients was diabetes mellitus (18.6%) followed by hypertension (10.7%). The average TIMI score was 3.45 and in terms of risk classification, 70.1% of them were Low Risk. The average ejection fraction (EF) in High-Risk patients based on TIMI score was significantly lower compared to Low-Risk patients (33.59±7.85% versus 37.62±7.11%; p=0.001). The mortality rate was 4.7% (25 patients), 7 patients (1.87%) were in the low-risk group and 18 patients (11.3%) were in the high-risk group, which showed a statistically significant difference between the two groups. (p=0.001). The average NLR in high-risk patients according to the TIMI score was significantly higher than in low-risk patients (3.90±5.01 vs. 2.43±3.71; p=0.004). In evaluating the predictive value of NLR for mortality, the obtained results show that the AUC was 0.646 (p=0.001) so the NLR values with a cut-off of 3.21 have a sensitivity of 83.3% and a specificity of 42.7% in predicting mortality.