P2496Results cardiopulmonary exercise testing in patients with obesity and chronic heart failure

Abstract

Abstract Purpose Determination of exercise tolerance in patients with obesity and chronic heart failure. Methods An exercise cardiorespiratory testing (CPET) was performed using a spiroergometer in combination with treadmill using the modified BRUCE protocol in 222 patients divided into the following groups: Group 1: obesity I-II grade – 60 patients; Group 2: obesity I-II grade + chronic heart failure (CHF) – 49 patients; Group 3: grade III obesity – 60 patients; Group 4: grade III obesity + CHF – 53 patients. Results The results of CPET showed that the reason for the decrease in tolerance to physical activity in patients with obesity without CHF is detraining. Patients with obesity and CHF were characterized by a more pronounced decrease in exercise tolerance, which was reflected in a decrease in peak oxygen consumption (VO2peak), which in patients with obesity I-II + CHF was equal to 72.7±3.4% (moderate decrease), and in patients with obesity III + CHF – 50±2.1% (marked decrease); differences when compared with the groups without CHF were 44.3% and 24.4% (p<0.001).The maximum aerobic performance of patients with obesity I-II + CHF was equal to 5.5±0.9 MET (moderate decrease), and in patients with obesity III + CHF – 3.8±0.4 MET (marked reduction); differences when compared with patients without CHF were significant at p<0.001. A small reduction in the global pumping function of the heart was found only in patients with obesity III + CHF – the oxygen pulse was 9.4±2.2 ml/beats and was significantly different from the group of patients without CHF. In addition, a decrease in alveolar gas exchange (VE/VCO2) was observed in the groups of patients with obesity and CHF, which was equal to 32.1±1.5 units in the group of patients with obesity I-II degree and 33.6±2.5 units in the group of patients with obesity Grade III (the norm is less than 32), which is probably due to the presence of pulmonary hypertension and a decrease in the ventilation-perfusion ratio. Conclusion The development of CHF in patients with obesity leads to impaired alveolar ventilation, a decrease in aerobic muscle power and tolerance to physical exertion. In addition, it was found that when performing a stress test in patients with obesity and CHF (unlike patients without CHF), the anaerobic threshold is reached before the stage corresponding to their average daily exercise. This means that the usual physical activity of patients does not allow them to carry out effective fat oxidation, which may be the metabolic cause of the progression of obesity in patients with CHF. Acknowledgement/Funding Research No. 0529-2019-0061 Diagnostics, prevention and dietaterapy of patients with alimentary-dependent diseases