TG/HDL-C Ratio as a Superior Diagnostic Biomarker for Coronary Plaque Burden in First-Time Acute Coronary Syndrome.

: Present ACS risk stratification predominantly depends on LDL-C, yet its diagnostic accuracy for coronary plaque burden remains limited. We examined whether extensive lipid profiling, specifically the TG/HDL-C ratio, could function as a more effective diagnostic instrument for forecasting significant plaque burden in treatment-naïve first-time ACS patients. : Among 722 ACS patients screened, 376 treatment-naïve patients undergoing PCI with complete lipid data were included. Exclusions ( = 346) were due to prior CAD, lipid-lowering therapy, renal/hepatic dysfunction, malignancy, pregnancy, or incomplete data. Coronary plaque burden was quantified by QCA, and patients were stratified by lesion count (0, 1, 2, 3, ≥4). The levels of lipids (LDL-C, HDL-C, TC, TG) and their ratios (LDL/HDL-C, TC/HDL-C, TG/HDL-C) were measured. Analyses included ANOVA (with Bonferroni correction), correlation, ordinal regression, and logistic regression (≥3 vs. <3 lesions). ROC analysis determined thresholds. : TG/HDL-C ratio increased progressively from 3.3 (0 lesions) to 5.3 (≥4 lesions). After Bonferroni correction, only TG/HDL-C retained significance ( = 0.009). Logistic regression confirmed TG/HDL-C as an independent predictor of high plaque burden (OR 1.25, 95% CI 1.09-1.42, = 0.004), outperforming LDL-C. : TG/HDL-C ratio is a superior diagnostic biomarker compared to LDL-C for identifying extensive coronary plaque burden. Integration into admission lipid profiling offers a cost-effective, actionable tool.