The Predictive Value of Platelet‐to‐Lymphocyte Ratio Before and After Percutaneous Coronary Intervention in Patients With Acute ST‐Segment Elevation Myocardial Infarction: A Retrospective Cohort Study in Palestine

BACKGROUND: Inflammation and thrombosis influence short-term outcomes after primary percutaneous coronary intervention (PCI) for acute ST-segment elevation myocardial infarction (STEMI). The platelet-to-lymphocyte ratio (PLR) is an inexpensive marker that may support bedside risk stratification. OBJECTIVE: To assess whether pre-PCI and post-PCI PLR predict in-hospital outcomes and 90-day all-cause mortality in STEMI patients undergoing primary PCI in Palestine. METHODS: This retrospective cohort study included STEMI patients referred for primary PCI at An-Najah National University Hospital. Of 413 eligible patients, 118 were excluded for incomplete records, leaving 295 patients for analysis. PLR was measured before and after PCI and dichotomized using ROC-derived cutoffs: pre-PCI PLR < 21.68 versus ≥ 21.68 and post-PCI PLR < 14.85 versus ≥ 14.85. Outcomes were compared between groups, and multivariable logistic regression was used to assess independent associations. RESULTS: Elevated pre-PCI PLR was associated with greater in-hospital clinical instability and remained independently associated with the composite in-hospital clinical endpoint, both per 10-unit increase (OR 1.41, 95% CI 1.13-1.74; p = 0.002) and using the cutoff ≥ 21.68 (OR 2.90, 95% CI 1.55-5.44; p < 0.001). However, pre-PCI PLR was not independently associated with heart failure or 90-day mortality. Post-PCI PLR showed stronger prognostic value and was independently associated with composite in-hospital events, heart failure, and 90-day mortality, both as a continuous variable and using the cutoff ≥ 14.85. CONCLUSION: Post-PCI PLR demonstrated stronger prognostic value than pre-PCI PLR and may serve as a simple, low-cost adjunctive marker for short-term risk stratification after primary PCI in STEMI patients.