Association Between Admission D-Dimer Levels and Coronary Anatomical Complexity Assessed by the SYNTAX Score in Patients With Acute Coronary Syndrome

Aim: D-dimer is a fibrin degradation product reflecting intravascular thrombotic activity. The SYNTAX score is an angiographic tool quantifying coronary anatomical complexity. The association between D-dimer levels and coronary anatomical complexity in acute coronary syndrome (ACS) remains incompletely characterized. This study aimed to evaluate the association between plasma D-dimer levels and SYNTAX scores in patients presenting with acute coronary syndrome (ACS).Material and Methods: A total of 388 patients with ACS who underwent percutaneous coronary intervention (PCI) were retrospectively analyzed. Patients were categorized based on D-dimer levels (<0.5 µg/mL FEU and ≥0.5 µg/mL FEU) and SYNTAX score classifications (low: 0–22, intermediate: 23–32, high: ≥33). High-sensitivity troponin I (Hs-TnI) was also measured at admission. Correlation analyses, binary logistic regression, and ROC curve assessments were performed.Results: D-dimer levels showed a significant positive correlation with SYNTAX scores (r = 0.385, p < 0.001). Among patients with D-dimer <0.5 µg/mL FEU, 83.9% had low SYNTAX scores, while only 5.1% had high scores. ROC analysis revealed an AUC of 0.70 (95% CI: 0.64–0.77) for D-dimer in identifying high SYNTAX scores, with 83% sensitivity and 59% specificity at a cut-off of 0.78 µg/mL FEU. In multivariable logistic regression, D-dimer was not an independent predictor of high SYNTAX score after adjustment for age, creatinine, and log-transformed Hs-TnI (OR: 1.891; 95% CI: 0.845–6.062; p = 0.200), whereas log(Hs-TnI) remained independently significant (OR: 1.195; 95% CI: 1.014–1.391; p = 0.024). D-dimer exhibited higher sensitivity than troponin in detecting high anatomical complexity.Conclusion: D-dimer levels show a statistically significant association with coronary anatomical complexity in ACS patients and may serve as a supplementary, non-invasive parameter for early risk stratification. However, D-dimer was not an independent predictor in multivariable analysis, and these findings require prospective multicenter validation before clinical implementation.