We measured levels of several parameters of immune inflammation (interleukins [IL] 1, 6, 8, 10, 12, tumor necrosis factor [TNF], serum neopterin, C-reactive protein) on days 10-14 after onset of ST segment elevation myocardial infarction (MI) and related them to results of 12 months follow up. Elevated titers of IL-12 and neopterin were significantly associated with unfavorable events (repetitive MI, progression of angina, stroke, decompensation of chronic heart failure) (=0.001 and =0.003, respectively). After adjustment for initial severity of MI only IL-12 retained its prognostic value (=0.05). Regression analysis identified IL-12 level >108.7 g/ml and TIMI score > 3 as independent predictors of combined end point formation. Prognostic value of IL-12 level was significant both among patients with TIMI scores <3 and more or equal 4.