STUDY AIM - assessment of dynamics of markers of inflammation (CRP, Il-6, Il-10, TNFa, CD40L, fibrinogen) and N - N in acute coronary syndrome (ACS) as well as analysis of effect of various methods of treatment on level of these parameters. Patient aged 30 - 70 years were included in the study: 52 patients with ACS with ST-segment elevation (STEACS) and 61 - without ST-segment elevation (NSTEACS). Initial level of markers of inflammation (Il-6, CRP) in STEACS was lower than in NSTEACS. Initial level of antiinflammatory Il-10 was significantly higher in patients in the STEACS group (72.6 +/- 39.1 and 6.6+4.2 pg/ml, < 0.01). At admission the highest values of N - N were noted in the group of NSTEACS (761.5 pg/ml compared with 451.1 pg/ml in STEACS, =0.04). During period of hospitalization elevation of N - N occurred in the group of STEACS while its lowering occurred in the group of NSTEACS. In STEACS patients with early restored coronary blood flow dysfunction of the myocardium was less pronounced (lower level of N - N ). In patients with NSTEACS during period of hospitalization levels of CRP, Il-6 fibrinogen lowered. In invasively treated patients with NSTEACS levels of CRP and fibrinogen lowered to a greater extent than in conservatively treated.