MAJOR ADVERSE CARDIOVASCULAR EVENTS (MACE) IN STEMI PATIENTS WITH ELEVATED NEUTROPHIL-TO-LYMPHOCYTE RATIO UNDERGOING PRIMARY PERCUTANEOUS CORONARY INTERVENTION-A STUDY IN PAKISTANI COHORT

Background: Cardiovascular diseases (CVDs) remain a leading cause of death globally, with approximately 20.5 million fatalities recorded in 2021, representing nearly one-third of all deaths.  Low- and middle-income countries (LMICs) bear a significant burden, accounting for 80% of these cases. This study aimed to evaluate the relationship between an elevated neutrophil-to-lymphocyte ratio (NLR) and the occurrence of major adverse cardiovascular events (MACE) in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). Methods: A retrospective observational study was carried out at tertiary care cardiac center in Rawalpindi, Pakistan, from December 2018 to May 2019. The study included 155 STEMI patients treated with PPCI. Patients with active infections, autoimmune disorders, hematologic malignancies, severe renal or hepatic impairment, or those receiving immunosuppressive therapy were excluded. NLR values were calculated from blood tests upon hospital admission, categorizing patients into two groups: those with elevated NLR (≥4.8) and those with lower NLR (<4.8). The primary outcome measured was in-hospital MACE, which included mortality and non-fatal myocardial infarction (MI). Statistical analysis involved univariate and multivariate logistic regression to identify independent predictors of MACE. Results: Among the 155 patients, 39 (25.2%) experienced MACE. The incidence of MACE was significantly higher in the elevated NLR group (84.6%) compared to the non-elevated group (15.4%) (p = 0.001). Univariate analysis showed a strong correlation between high NLR and increased MACE risk (OR: 2.11; 95% CI: 1.61–2.76; p = 0.001). Further multivariate analysis, after adjusting for confounding variables, confirmed NLR as an independent predictor of MACE (AOR: 2.08; 95% CI: 1.57–2.74; p = 0.001). Conclusion: A high NLR serves as a significant predictor of MACE in STEMI patients undergoing PPCI. Due to its ease of measurement and cost-effectiveness, NLR could be a valuable biomarker for early risk assessment and targeted intervention in STEMI management.