Aggregate Index of Systemic Inflammation as a Predictor of Acute Stent Thrombosis in STEMI Undergoing Primary PCI.

Acute stent thrombosis (ST) after primary percutaneous coronary intervention (pPCI) for ST-segment elevation myocardial infarction (STEMI) is uncommon but often fatal. We evaluated whether the Aggregate Index of Systwemic Inflammation (AISI) predicts acute ST and in-hospital mortality. In this retrospective cohort, 3055 consecutive STEMI patients underwent pPCI with stent implantation. Admission AISI was calculated as (neutrophils × monocytes × platelets)/lymphocytes. Multivariable logistic regression identified independent predictors; receiver operating characteristic (ROC) analysis assessed discrimination for acute ST. Acute ST occurred in 76 patients (2.5%) and was associated with higher in-hospital mortality (15.8% vs 3.8%, P < .001). AISI was higher in patients with acute ST (1314.2 vs 689.7, P < .001) and independently predicted acute ST (OR 1.03, 95% CI 1.02-1.05). AISI showed moderate discrimination area under the curve (AUC) 0.720; cut-off 904.97; sensitivity 64.2%; specificity 64.3%). Higher AISI was also independently associated with in-hospital mortality (OR 1.05, P < .001). Admission AISI is independently associated with acute ST and early death after pPCI for STEMI, supporting its use as a rapid, low-cost risk marker pending prospective validation.