The identification of new
biomarkers allowing an early and more accurate characterization of patients with
ST-segment elevation myocardial infarction (
STEMI) is still needed, and exosomes represent an attractive diagnostic tool in this context. However, the characterization of their
protein cargo in relation to cardiovascular clinical manifestation is still lacking. To this end, 35
STEMI patients (17 experiencing resuscitated
out-of-hospital cardiac arrest (OHCA-
STEMI) and 18 uncomplicated) and 32 patients with chronic coronary syndrome (CCS) were enrolled. Plasma exosomes were characterized by the nanoparticle tracking analysis and Western blotting. Exosomes from
STEMI patients displayed a higher concentration and size and a greater expression of platelet (GPIIb) and vascular endothelial (
VE-cadherin) markers, but a similar amount of cardiac
troponin compared to CCS. In addition, a difference in exosome expression of
acute-phase proteins (
ceruloplasmin,
transthyretin and
fibronectin) between
STEMI and CCS patients was found. GPIIb and brain-associated marker PLP1 accurately discriminated between OHCA and uncomplicated
STEMI. In conclusion, the exosome profile of
STEMI patients has peculiar features that differentiate it from that of CCS patients, reflecting the pathophysiological mechanisms involved in
STEMI. Additionally, the exosome expression of brain- and platelet-specific markers might allow the identification of patients experiencing ischemic
brain injury in
STEMI.