Effect of cardiac rehabilitation on exercise ventilatory oscillations in patients with chronic heart failure

Abstract

Cardiovascular rehabilitation (CVR) is recommended in patients with heart failure (HF) to reduce mortality and new hospitalizations. A cardiopulmonary exercise testing (CPX) presents prognostic criteria such as the presence of exercise oscillatory ventilation (EOV). The aim of our study was to analyse the impact of CVR on EOV and the prognostic value of an evolution of EVO after CVR in a population of chronic heart failure patients. Retrospective, monocentric study including HF patients with reduced/intermediate left ventricular ejection fraction (i.e. < 50%) who participated to a CVR programme in our institution from July 2013 to November 2020, consisting of 21 sessions with a CPX at the first and last sessions. The presence of EOV at the CPX priori to CVR defined the EOV+ and EOV- groups. The main outcome of the study was the resolution of EOV after CVR. The secondary outcome was the occurrence of rehospitalisation for HF and/or death during follow-up, and according to the EOV status. Among the 142 patients included, 24 (17%) had EOV (EOV+ group). The VE/VCO2 slope before CVR was significantly increased in the EOV+ vs. EOV- patients (39.6 ± 5.9 vs. 36.8 ± 6.1 P = 0.05). Regarding the main outcome, EOV resolution was noted after CVR in 14 patients (58.3%, P < 0.01). The 10 patients (7%) with maintained EOV had a significant decrease of the length of the EOV cycle (40.2 ± 12.8 vs. 49.5 ± 15.3 sec, P = 0.005). After a mean follow-up of 31 ± 22 months, we found no difference in the rates of occurrence of the secondary outcome according to the post-CVR EOV status. Cardiovascular rehabilitation is associated with a substantial resolution of EOV (or EOV cycle length) in patients with chronic heart failure. However, the prognostic value of this phenomenon is uncertain.