Modelling the Impact of Extracellular Vesicle Cargoes in the Diagnosis of Coronary Artery Disease

Objectives: We aimed to assess the relationship between circulating extracellular vesicles (EVs), hypoxia-related proteins and conventional risk factors of the life threatening coro-nary artery disease (CAD) to find more precise novel biomarkers. Methods: Patients were categorized based on coronary CT angiography (CCTA). Patients with a Segment Involvement Score (SIS) > 5 were identified as CAD patients. Individuals with a SIS < 5 were considered as control subjects. Characterization of EVs and analysis of plasma concentration of GDF15 were performed by multicolor or bead-based flow cytom-etry. Plasma protein levels of PYGM, clusterin, CPN1 were determined by ELISA. Multiple logistic regression was used to determine the association of the biomarkers with the CAD outcome after accounting for established risk factors. The analysis was built in 3 steps: first, we included the basic clinical and laboratory variables (Model 1), then we integrated the plasma protein values (Model 2), and finally complemented it with the circulating EV pattern (Model 3). To assess the discrimination value of the models, an area under the re-ceiver operating curve was calculated and compared across the three models. Results: The AUC values were 0.68, 0.77 and 0.84 in Models 1, Model 2 and Model 3, re-spectively. The variables with the greatest impact on the AUC values were Hemoglobin 0.2 (0.16-0.26) in Model 1, CPN1 0.12 (0.09-0.14) in Model 2, and circulating CD41+/CD61+ EVs 0.31 (0.15-0.5) in Model 3. Correlation analysis showed a significant impact of circu-lating CD41+/CD61+ platelet-derived EVs (p=0.03, r=-0.4176) in Model 3. Conclusion: Based on our results, the circulating EV profile can be used as a supportive biomarker along with the conventional laboratory markers of CAD, and it enables a more sensitive, non-invasive diagnostic analysis of CAD.