Association between Triglyceride-Glucose Index and In-Hospital Outcomes in Patients with ST-Elevation Myocardial Infarction Undergoing Percutaneous Coronary Intervention.

Background: The triglyceride-glucose (TyG) index is a reliable surrogate biomarker for insulin resistance and has been linked to adverse outcomes in coronary artery disease. However, its association with in-hospital major adverse cardiovascular events (MACE) in ST-elevation myocardial infarction (STEMI). Objectives: To examine the association between the TyG index and in-hospital MACE as the primary outcome in STEMI patients undergoing percutaneous coronary intervention (PCI). Methods: A prospective cross-sectional study enrolled 285 STEMI patients undergoing PCI. Patients were stratified into low TyG (≤ 8.805; n =81) and high TyG (> 8.805; n = 204) groups. In-hospital MACE was defined as a composite of all-cause death, cardiogenic shock, acute heart failure, life-threatening arrhythmia, stroke, and mechanical complications. Results: The high TyG group had significantly higher rates of LVEF ≤ 40% (66.7% vs. 39.5%, p<0.001) and multivessel disease. Of 285 patients, 110 (38.6%) experienced in-hospital MACE. Multivariable logistic regression identified high TyG as an independent prognostic marker of in-hospital MACE (OR = 5.90, 95% CI: 2.29-15.20, p<0.001). The ROC curve yielded an AUC of 0.72 (95% CI: 0.66-0.78, p<0.001), with an optimal cutoff of 9.19 (sensitivity 78.2%; specificity 61.1%). Conclusion: Elevated TyG index is an independent predictor of in-hospital MACE in STEMI patients undergoing PCI, and is significantly associated with reduced LVEF and multivessel coronary disease. As a simple, low-cost index calculable at admission, TyG may serve as a practical adjunct for early risk stratification.