Pan-Immune-Inflammation Value as a Novel Predictor of Contrast-Associated Acute Kidney Injury in Patients Treated with Primary PCI for STEMI

<b>Background/Objectives:</b> Contrast-associated acute kidney injury (CA-AKI) remains an important cause of morbidity and mortality in patients undergoing procedures that require intravascular contrast administration. Therefore, the early identification of high-risk individuals is paramount, above all for ST-segment elevation myocardial infarction (STEMI) patients in need of urgent percutaneous coronary intervention (PCI). <b>Methods:</b> This retrospective study evaluated the prognostic value of the Pan-Immune-Inflammation Value (PIV), a composite inflammatory index, in predicting CA-AKI among patients presenting with STEMI who received urgent PCI within a 12 h window from the onset of symptoms. <b>Results:</b> This study recruited 2325 patient. CA-AKI was defined as a >25% or ≥0.5 mg/dL increase in serum creatinine within 48-72 h after the procedure. Patients were categorized into CA-AKI (+) and CA-AKI (-) groups. PIV levels were significantly higher in patients who developed CA-AKI (502.5 ± 324.5 vs. 264.7 ± 165.8; <i>p</i> < 0.001). ROC analysis identified a PIV cutoff value of >320, yielding an AUC of 0.753 (95% CI: 0.740-0.787; <i>p</i> < 0.001), with 67% sensitivity and 66.9% specificity. Multivariate logistic regression confirmed that PIV > 320 independently predicted CA-AKI (OR 2.118; 95% CI: 1.329-3.790; <i>p</i> < 0.001). In multivariable analysis, age, Killip class, contrast volume, and PIV > 320 were identified as independent predictors of CA-AKI. <b>Conclusions</b>: Elevated admission PIV serves as an independent and practical biomarker for predicting CA-AKI in STEMI patients undergoing PCI.