Abstract 16961: Characterization of Extracellular Vesicles and RNA Content and Its Relevance to Thrombo-Inflammatory Biomarkers in Patients With Acute Pulmonary Embolism

Abstract

Introduction: Pulmonary embolism (PE) is a complex disease with significant morbidity and mortality rates globally. Previous studies have shown that extracellular vesicles (EV) carrying disease specific ribonucleic acids (RNA’s) may contribute to pro-inflammatory and pro-coagulant state in VTE. This study aimed on profiling EV related parameters, RNA content, and thrombo-inflammatory markers in patients with acute PE compared to healthy individuals. Materials & Methods: Prospective cohort of patients with PE (n=72) were compared with normal healthy individuals (n=19) and further stratified by PE severity. Blood samples were collected under an IRB-approved project from Loyola University Chicago. Plasma samples were analyzed for the EV parameters, RNA parameters, and thrombo-inflammatory markers (D-Dimer, PAI-1, and CRP) respectively. Results: PE cohort includes 72 patients (41 male, and 31 female) with a median age of 67-years (interquartile range; IQR= 53-76), and a median body mass index (BMI) of 27.5-kg/m 2 (IQR= 24.7-35.7). Compared to controls, EV concentration, and EV/ng RNA were significantly (p= <0.05) lower, while D-Dimer, CRP and PAI-1 were significantly (p= <0.05) higher in patients with PE. In correlation analysis, varying levels of positive and negative correlations between the EV, and RNA parameters, and thrombo-inflammatory markers were noted (Figure 1). Upon stratification on PE severity, D-dimer was higher in massive PE compared to low-risk (p= 0.012), and sub-massive PE (p=0.036) respectively. Conclusion: These studies demonstrate significant changes in extracellular vesicles, RNA content and thrombo-inflammatory markers in acute PE patients compared to healthy controls. These changes may be due to the drivers of VTE pathogenesis or the result of a consumption process in acute PE. Further large scales studies on disease specific exosomes and RNA signatures are warranted to understand their relevance.