Aim. To study the effect of mexidol on N-terminal pro B-type natriuretic peptide (NT-proBNP), markers of oxidative stress, inflammatory reaction and endothelial dysfunction in patients with chronic brain ischemia and chronic heart failure II-III NYHA functional class while 13 weeks of sequential intravenous and oral therapy with mexidol and standard therapy. Material and methods. Study included 44 patients with chronic brain ischemia and chronic heart failure II-III NYHA functional class with ejection fraction less 50%. Mean age: 65.5±11.8 years, 75% men. 21 patients of group mexidol plus standard therapy of chronic heart failure received mexidol at a dose of 1000 mg/day by intravenous infusion for 7 days followed by oral doses of 250 mg three times a day for twelve weeks, 23 patients received standard therapy. 34 patients completed the trial, in 10 patient the final visit was performed as telephone call due to epidemiologic situation. Concentration of N-terminal pro B-type natriuretic peptide (NT-proBNP), markers of oxidative stress (malonic dialdehyde (MDA), superoxide dismutase (SOD)), inflammatory reaction (C-reactive protein (CRP), tumor necrosis factor α (TNFα)), homocysteine and cystatin C were examined in blinded manner in all patients initially, on day 7 and week 13. Results. Statistically significant more prominent decrease of NT-proBNP, MDA, CRP and TNFα and increase of SOD by day 7 and week 13 were observed in patients treated with mexidol along with standard therapy in comparison with group treated with standard therapy. Conclusion. Mexidol added to standard therapy of patients with chronic brain ischemia and chronic heart failure II-III functional class decreases concentration of NT-proBNP, has proven antioxidant activity, decreases the degree of inflammatory reaction, slows down the increase of homocysteine, does not influence the kidney function (by measurement of cystatin C). © 2020, Media Sphera Publishing Group. All rights reserved.