Absence of exercise capacity improvement after in-hospital short-term cardiac rehabilitation is associated with long-term clinical outcome in heart failure patients

Abstract

Abstract Background Previous studies suggest Cardiac rehabilitation (CR) improve exercise capacity and decline mortality in heart failure (HF) patients. However, some studies show there are HF patients who do not improve exercise capacity by CR and these patients have a higher risk of adverse events in long-term clinical outcome. We investigated whether absence of exercise capacity improvement after in-hospital short-term CR also has adverse effect in long-term clinical outcome. Methods In this retrospective study, 130 HF patients who underwent two weeks in-hospital CR after received standardized HF treatment between July 2014 and August 2020 were included. Improvement in exercise capacity was assessed by change in peak oxygen consumption (delta-Peak VO2) measured at 1st and 14th day of CR by cardiopulmonary test. The median delta-PeakVO2 was 1.3 ml·kg-1·min-1. Patients were classified as responder if they demonstrated delta-PeakVO2 ≥1.3 ml·kg-1·min-1 and as non-responder if they demonstrated delta-PeakVO2 <1.3ml·kg-1·min-1. MeanΩ follow-up was 1236 days. The primary outcome was all-cause death. Result 63 patients (48.4%) were classified as non-responder. Non-responders were older (75.5±10.6 vs 70.8±11.0, P=0.01) and lower estimated glomerular filtration rate (eGFR) (49.7±19.4 vs 57.9±19.2) and lower albumin (3.5±0.5 vs 3.7±0.3 g/dL, P=0.04) than responders. Transtricuspid pressure gradient (TRPG) measured by transthoracic echocardiography was also higher in non-responders (28.5±10.9 vs 22.7±6.3). Predictor of non-responders were TRPG (OR = 1.1, 95% CI 1.02–1.26) and albumin (OR =0.04, 95% CI: 0.003–0.40). In multivariate analysis including delta-PeakVO2 <1.3 ml·kg-1·min-1 (non-responder), age >75, male gender, PeakVO2 at 1st day of CR, body mass index (BMI), left ventricular ejection fraction measured by transthoracic echocardiography, medication of β-blockers showed that delta-PeakVO2 <1.3 ml·kg-1·min-1 (HR =2.8, 95% CI 1.0–7.5), age>75 (HR11.2, 95% CI 2.1–60.1), BMI (HR =0.8, 95% CI 0.6–0.96) were associated with all-cause death. Conclusion The absence of exercise capacity improvement after in-hospital short-term CR was the risk of all-cause death. Especially, the HF patients with higher TRPG and lower albumin have a higher probability of becoming a non-responder. Funding Acknowledgement Type of funding sources: None.