0350 : Serum level of IL-17A and infarct size in patients with acute ST-elevated myocardial infarction

Background Myocardial infarction (MI) is one of the main causes of death in the world. Infarct size (IS) is associated with heart failure and mortality following MI. Early reperfusion is currently the most effective treatment to reduce IS resulting from MI. Although reperfusion reduces infarct size, it can also lead to reperfusion injuries. Recently, it was shown that interleukin- 17A (IL-17A) is involved in the pathophysiology of reperfusion injuries. However, the correlation between IS and the IL-17A level in humans is unknown. Our aim was to evaluate whether the IL-17A serum level and the IL-17A active fraction was correlated with IS in humans. Methods We selected 101 patients who presented with a ST-elevated Myocardial Infarction (STEMI) and 10 healthy controls. For each patient blood samples at admission (H0) and 4 hours after admission (H4) were collected. IL-17A serum levels were assessed using ELISA and the active fraction was assessed with a functional test. IS was determined by peak troponin level and peak CK level for every patient and by cardiac magnetic resonance imaging (CMR) for 20 patients. Results The IL-17A serum level was significantly increased in STEMI patients compared to the healthy controls, showing a median value of 0.9 pg/mL Interquartile Range IQR [0.0-3.2] at H0 and 1.0 pg/mL IQR [0.2-2.8] at H4 versus 0.2 pg/mL IQR [0.0-0.7] for healthy controls. The serum level of IL-17A did not correlate with IS (r=–0.02475, p=0.80 at H0 and r=0.04425, p=0.66 at H4 for peak troponin level; r=–0.03390, p=0.74 at H0 and r=0.02276, p=0.82 at H4 for peak CK level and r=–0.2593, p=0.28 and r= –0.2884, p=0.23 for CMR). As for the serum IL-17A level, no correlation was found between the active fraction of IL-17A and IS. Conclusion Serum IL-17A level is significantly increased in patients at the early phase of acute MI compared to healthy controls. However, the level of IL-17A in the acute phase of MI does not correlate with IS.