Aim. To evaluate the contribution of SOD1, CAT, PXDN1, NOS3, EDN1, VCAM, ICAM, PECAM, SELE and SELP genes to the pathogenesis of infective endocarditis in patients undergoing cardiac surgery.Material and Methods. We studied 25 native heart valves obtained from patients with infective endocarditis and 13 native heart valves obtained from patients with other valvular pathology. The expression of SOD1, CAT, PXDN1, NOS3, EDN1, VCAM, ICAM, PECAM, SELE and SELP genes was determined by qPCR. Immunofluorescent staining was performed using specific primary antibodies to nitrotyrosine.Results. Native heart valves obtained from infective endocarditis patients were characterized by the decreased expression of genes involved in the processes of oxidative stress and genes encoding cell adhesion molecules. Immunofluorescence staining showed that the heart valves obtained from infective endocarditis patients had lower nitrotyrosine staining compared to the control suggesting the decreased oxidative stress.