All rights reserved. Relevance: Congestive heart failure in dogs is an urgent problem for Doctor of Modern Veterinary cardiology. Endocardiosis, or myxomatous mitral valve degeneration, is the most common acquired heart disease of dogs that has a potential adverse outcome. Accurate and timely diagnosis for this cardiopathology in dogs, and also effective monitoring of the progression of congestive heart failure syndrome are the most important problems of veterinary medicine. Purpose of research: To study the commitment of owners whose dogs with mitral valve endocardiosis to assess the respiratory rate of their pets during sleep and its impact on the survival of sick animals. Materials and methods. A prospective study of the survival rate of 181 dogs with mitral valve endocardiosis, complicated by congestive heart failure syndrome. Results: It was found that the degree of owners' commitment to assess the respiratory rate during sleep has a significant impact on the survival of dogs with mitral valve endocardiosis. The median life expectancy of sick dogs whose owners had a high commitment to monitoring respiratory function was significantly high. The survival time of sick dogs whose owners showed high adherence to the test was on average 604.8±53.1 days (variation from 0 to 1378; median-452 days). In sick animals whose owners showed low adherence to assess the respiratory rate, the life expectancy was significantly low and averaged 279.9±28.9 days (variation from 0 to 1156; median-122 days). In the Mann-Whitney test, this difference was found to be significant (p