Objective Coagulation Assays for Predicting Thrombosis in Peripheral Artery Disease

BACKGROUND: Thrombosis of stents or bypass grafts is a major cause of amputation in patients with peripheral artery disease (PAD) postrevascularization. Thromboprophylaxis remains vital in thrombosis prevention, but there are limited data on using objective coagulation tests as predictive tools. Our group demonstrated previously that thromboelastography with platelet mapping (TEG-PM) may predict thrombosis. However, the use and relation of calibrated automated thrombography (CAT), a test that directly measures thrombin generation (TG) with TEG-PM, remains unknown. This study aims to evaluate the use of CAT in predicting thrombosis and delineate the correlation between CAT and TEG. STUDY DESIGN: Patients with PAD postrevascularization at a single tertiary center were prospectively enrolled and followed from 2021 to 2024. CAT, a fluorogenic assay for TG, and TEG, a viscoelastic test for clot formation, were performed at 1 week, 1, 3, and 6 months. Patients who thrombosed were compared with those who did not. Statistical analysis was performed using the Mann-Whitney U test, receiver operating characteristic curves, and Spearman correlations. RESULTS: Of the 79 patients (mean age 71.31 ± 7.1, 67.1% men), 20 developed thrombosis. The thrombosis group showed higher peak TG and TG rate. Peak thrombin inversely correlated with citrated kaolin assay reaction time (ρ = -0.33), citrated kaolin assay + heparinase reaction time (ρ = -0.32), and positively with citrated functional fibrinogen functional fibrinogen level (ρ = 0.24). TG rate was inversely correlated with reaction time (ρ = -0.28), citrated kaolin assay reaction time (ρ = -0.37), and citrated kaolin assay + heparinase reaction time (ρ = -0.39; all p < 0.05). CONCLUSIONS: The correlation suggests that CAT may serve as a complementary tool to TEG for thrombotic risk assessment in PAD, guiding personalized thromboprophylaxis.