During period from 1 January 2012 to 31 December 2014, 142 procedures of the surgical treatment of mitral valve insufficiency have been performed at the National M.M. Amosov Institute of Cardiovascular Surgery. The average age of the patients was 61.8±7.4 years. Arterial hypertension was diagnosed in 59.9 % (n=85) patients, diabetes mellitus – in 14.8 % (n=21), peripheral arterial disease – in 16.2 % (n=23), anamnestic stroke – in 3.5 % (n=5). Valve preserving surgery of mitral valve (plastic surgery) was performed in 93 (65.5 %) patients, mitral valve prosthesis – in 49 (34.5 %). We studied complications in the early postoperative period. Heart failure was most prevalent in the study group, being diagnosed in 40 (28.2 %) patients, and constituted 71.4 % among all early post surgery complications. Special attention was paid to the protection of the myocardium. Introduction of the myocardial protection method with additional usage of the cardioplegic solution through bypass grafts decreased the prevalence of early post surgery heart failure to 22.1 %.