Background: Inflammatory factors are involved in the cardiac remodelling process after myocardial infarction (MI). Pronounced and sustained activation of proinflammatory factors is believed to enhance the damage to the myocardium and leads to its dysfunction and heart failure. Anti-inflammatory factors, especially interleukin-10 (IL-10), exert a protective action by reducing excessive inflammatory reactions. Aim: To asses the relationship between serum levels of IL-6, IL-10, CRP and echocardiographic indices of myocardial function in patients with ST-elevated myocardial infarction (STEMI) treated with primary angioplasty. Prognostic value of IL-6, IL-10 and CRP levels in predicting systolic and diastolic dysfunction 6 months after MI was also assessed. Methods: We studied 75 patients aged 36-82 (28 women and 47 men) presenting with STEMI treated with primary angioplasty. Blood samples for assesment of IL-6, IL-10 and CRP levels were on days 3 and 7 (3d, 7d) of MI and after 6-month follow-up (6m). Echocardiographic examination was performed on day 7 and 6 months after MI during which the parameters of LV systolic (LVEF, WMSI) and diastolic function (E/A, DT, IVRT, Ep, E/Ep) were evaluated. Twenty four healthy persons served as controls. Results: Interleukin-6 and CRP levels in consecutive measurements correlated significantly inversely with LVEF (7d) and LVEF (6m). The IL-10 (7d) and IL-10 (6m) level correlated positively with LVEF (6m) (r=0.39, p=0.02; r=0.27, p=0.04). The IL-6 and CRP levels in consecutive measurements correlated significantly positively with E/A and E/Ep and inversely with IVRT, DT and Ep. The IL-10 (3d) level correlated inversely with DT (6m) (r=–0.25, p=0.04), while IL-10 (7d) level correlated positively with DT (6m) (r=0.36, p=0.004). Increased level of IL-6 (3d) and CRP (3d) was an independent prognostic factor of LV systolic (OR=1.27, p=0.02; OR=1.14, p=0.05) and diastolic dysfunction (OR=1.14, p=0.03; OR=1.05, p=0.01) 6 months after MI. Conclusions: 1. A significant, correlations between increased IL-6, CRP level and impaired LV systolic and diastolic function indicate the possible involvement of these factors in postinfarction cardiac damage. 2. Increased level of IL-6 and CRP in the acute phase of MI is an independent predictor of LV systolic and diastolic dysfunction 6 months after MI. 3. Increased serum level of IL-10 in the acute phase of MI reflects the extension of post-infarction myocardial lesion. 4. Maintenance of increased level of IL-10 for days/months after MI seems to be prognostically beneficial.