Acute coronary syndrome (ACS) represents a major cause of hospitalization, disability and death worldwide. After high-sensitivity (hs)-troponin assay implementation, incidence of unstable angina (UA) dramatically decreased, and patients were considered as a population with lower rates of death, major adverse cardiac events (MACEs) and obstructive coronary artery disease (CAD) compared with the non-ST elevation myocardial infarction (NSTEMI) group. However, UA patients showed higher rates of future myocardial infarction and coronary revascularizations compared with healthy controls. Furthermore, according to the recent international guidelines, a routine invasive strategy is recommended in both NSTEMI and UA patients during hospitalization. As a consequence, a large number of coronary angiographies (CAGs) are performed in patients that, according to evidence, show considerable percentage of non-obstructive CAD. Therefore, the identification of valuable biomarkers to predict obstructive CAD in NSTEMI and UA patients still represents an unmet need. To address this issue, so far, both free circulating microRNAs (miRs) and miRs enriched in extracellular vesicles (EVs) have been investigated as possible tools to stratify ACS patients without providing suitable information. Aim: Therefore, based on our previous data, this study was designed to investigate the potential application of EVs recovered from NSTEMI and UA patients as biomarkers to predict obstructive CAD in these patients. Specifically, we analysed EV troponin content, their cell of origin, and their miR and protein cargo as predictors of obstructive critical CAD in NSTE-ACS patients. Results: We enrolled 140 patients with diagnosis of UA and NSTEMI who underwent CAG and then circulating EVs profiling was performed. We demonstrated that circulating EVs largely originate from platelets and endothelial cells. Moreover we found a correlation between EV CD62P surface marker, miR-126-5p, and miR-130a-3p content and the absence of critical CAD. Finally, by Mass spectrometry of EVs we demonstrated a differential clusterization of EV protein content between patients with and without obstructive CAD. Proteins associated with lipid transport/metabolism were found; enriched in EVs from patients without obstructive CAD. Conclusion: The results of this study provide evidence for circulating EVs as predictive biomarkers of critical obstructive CAD in NSTE-ACS patients.