Cardiac Troponin-T Release within Small Extracellular Vesicles in Type 1 vs. Type 2 Myocardial Infarction

Abstract

Distinguishing type 1 myocardial infarction (T1MI) vs type 2 myocardial infarction (T2MI) is challenging as both lead to cardiac troponin-T (cTnT) elevations. As the prognosis and treatments of T1/T2MI are distinct, accurate and timely diagnoses are crucial, but unavailable with standard cTnT testing. A cTnT release mechanism bound by small extracellular vesicles (sEV) was identified, possibly more associated with T2MI, which offers differentiating potential. Accordingly, 52 patient serum samples were collected, including healthy control, T1MI, and T2MI-Ischemic heart failure (HF) or non-ischemic hypertrophic cardiomyopathy (HCM). T1MI patients showed significantly higher absolute cTnT levels with sEVs containing 31.75±5.39% (mean±SEM). Comparatively, T2MI-HCM showed overall lower cTnT levels, and sEV proportion of 48.30±3.39%. The intermediate state, T2MI- Ischemic HF showed sEV cTnT to be present at 22.17±4.45%, more like T1MI. This early-stage analysis indicates that sEV cTnT displayed proportional variation across disease states consistent with alternate release profiles, which could assist in differentiating T1/T2MI.