116 stable (NYHA II–III) chronic heart failure patients (pts) with ischemic left ventricular systolic dysfunction (ejection fraction 45 %) on standard treatment were examined. The structure and function of heart were assessed by echocardiography. Flow-mediated vasodilatation (FMD) of a. brachialis was studied by standard culf test. The markers of oxidative stress (dien conjugates and malon dialdehyde), antioxidative enzymes (superoxyddismutase activity and glutathione reductase) were measured by spectrofluorometric and spectrophotometric methods. eNOS Т (–786)С polymorphism was genotyped by polymerase chain reaction. In order to analyze the influence of nebivolol on FMD with genotypes of Т(–786)С gene eNOS polymorphism it was prescribed to 16 pts (TT (n=7), TC+CC (n=9). FMD in pts with genotype TT was 7.2 [4.9; 8.3] %; in pts with genotype TC – 6.6 [4.4; 9.1] %, whereas FMD in pts with genotype CC was 4.7 [2.8; 6.0] %, in comparison with FMD genotype CC vs TT – Р=0.034, CC vs TC – Р=0.046. The functional class NYHA, structure and function of heart parameters, markers of oxidative stress and antioxidative enzymes were similar in genotypes TT, TC and CC of Т (–786) С polymorphism. Nebivolol has the same effect on FMD in pts with TT, TC and CC of Т(–786)С gene polymorphism eNOS. The prognosis of long-term survival (2.5 years) of pts with genotype CC was worse than of pts with genotype TT (P=0.046).