Introduction: MicroRNAs (miR) are short, non-coding small RNAs, involved in pathological pathways of a large amount of cardiovascular diseases (CVD). However, their role in early diagnosis and prognosis of different CVD is still controversial.
Objective: To determine the association of circulating miR, which were suggested to have possible cardio vascular implications (miR126 and miR146), with left ventricular ejection fraction (LVEF), global longitudinal strain (GLS), and arterial function, in patients with stable and unstable coronary artery disease (CAD).
Methods: 70 patients with CAD (68% men, 58 +/- 12 years), including 57 patients with ST elevation acute myocardial infarction (STEMI) (27 patients with diabetes, 30 without diabetes) and 13 patients with stable CAD, were assessed within 24 hours of admission by serum microRNA analysis, 2D and 3D echocardiography (for LVEF and GLS), and evaluation of arterial function (EP and β index, CAVI and ABI).
Results: For the whole group, higher miR126 was associated with lower 2D LVEF (r=-0.32, p=0.048). In pa-tients with STEMI and diabetes, higher miR126 was associated with lower 2D LVEF (r=-0.54, p=0.038), while in patients with STEMI without diabetes higher miR126 was associated with lower 2D GLS (r=-0.61, p=0.035). Furthermore, miR126 was associated with parameters of arterial stiffness, assessed by R-CAVI and L-CAVI in all patients with STEMI (r=0.35 and r=0.39, respectively, p<0.05) and by EP and β indexes in pati-ents with STEMI without diabetes (r=0.72, and r=0.59, respectively, p<0.05). Circulating levels of miR146 were higher in patients with STEMI vs. stable CAD (95% CI 1.46-8.22, p=0.006). In patients with STEMI and diabe-tes, higher miR146 was associated with higher tropo-nin I (r=0.76, p<0.0001), while in patients with STEMI without diabetes higher miR146 was associated with lower 3D GLS (r=-0.47, p=0.04).
Conclusions: Circulating micro-RNAs might be new biomarkers for the early diagnosis and detection of cardiac dysfunction in patients with CAD. Further studies are necessary in order to determine their predictive value and their possible involvement in therapeutic strategies.