The CALLY index as a novel predictor of left ventricular aneurysm in patients with ST-segment elevation myocardial infarction.

BACKGROUND: Left ventricular aneurysm (LVA) is a serious mechanical complication following ST-segment elevation myocardial infarction (STEMI). The C-reactive protein-albumin-lymphocyte index (CALLY) is a novel composite inflammatory biomarker, but its predictive value for LVA remains unclear. METHODS: We retrospectively enrolled 1,507 STEMI patients who underwent primary percutaneous coronary intervention (pPCI) between January 2020 and March 2026. Patients were divided into quartiles based on CALLY levels. Restricted cubic spline (RCS) analysis was used to explore the dose-response relationship. Least absolute shrinkage and selection operator (LASSO) regression was used for variable screening. Multivariable logistic regression was performed to identify independent predictors. A nomogram was built and validated using receiver operating characteristic (ROC) curves, bootstrap calibration curves, and decision curve analysis (DCA). RESULTS: LVA occurred in 157 patients (10.42%). The incidence of LVA declined gradually with increasing CALLY quartiles (27.32%, 7.18%, 3.98%, 3.18%; P < 0.001). RCS verified a nonlinear inverse association between CALLY and LVA risk (P for nonlinearity<0.05). After adjustment, CALLY (Q4 vs. Q1: OR = 0.32, 95%CI: 0.15-0.69, P = 0.003), Killip class ≥2, infarct-related artery-left anterior descending (IRA-LAD), left ventricular ejection fraction (LVEF), and cardiac troponin I (cTnI) ≥ 50 ng/mL were independent predictors of LVA. The nomogram based on these five predictors showed good discrimination (AUC=0.931), acceptable calibration, and favorable clinical net benefit. CONCLUSION: A lower admission CALLY index was independently associated with a higher risk of LVA in STEMI patients treated with pPCI. The CALLY-based nomogram supports reliable risk stratification and may assist with early clinical decision-making.