The Effect of Oxygen Supplementation in Training in Heart Failure Patients on Aerobic Performance and Quality of Life

Background: Physical training in patients with heart failure has been proven to reduce mortality and hospitalization rates, but many have difficulty performing an effort due to a lack of oxygen supply to the muscle and its fatigue. The effect of supplementing oxygen in a single effort was found to improve the level of oxygen reaching the muscle, the duration and intensity of the effort. The effect of supplemental oxygen during an exercise program in heart failure patients on exercise performance has not yet been examined. The aims of the study: 1. To test the effect of a training program with oxygen supplementation, on maximal and submaximal aerobic exercise, six-minute walk (6MWT) and quality of life in patients with heart failure. 2. Testing the effect of oxygen supplementation in a single effort on the lactate concentration and performance of the effort. Methods: 24 independent heart failure patients, without a decrease in saturation, with an ejection fraction \<50% were recruited for the study and were randomly divided into two groups, a training group with supplemental oxygen (O2) and a control group that trained without supplemental oxygen. Before and after a training program that lasted two months, the following were tested: maximal aerobic power, submaximal aerobic exercise time, 6MWT, disease severity according to the New York Heart Association - NYHA and quality of life according to the Kansas Questionnaire (KCCQ)). In addition, a single submaximal effort was performed at 80% of maximum heart rate with and without oxygen supplementation. Every 3 minutes the lactate concentration, heart rate and the difficulty of the effort were measured. To test the effect of the intervention on the outcome measures, a 2way ANOVA test was performed for repeated measurements. Importance of the study: The results of the study will make it possible to examine for the first time the effect and importance of oxygen supplementation during training in cardiac rehabilitation s