Lumbar-Type Hybrid Assistive Limb Improves Short Physical Performance Battery for Aged Patients With Decompensated Heart Failure in Cardiac Rehabilitation.

Background: Unlike the outpatient cardiac rehabilitation (CR) program for chronic heart failure (HF), the acute-phase inpatient CR program is not well established. We aimed to examine whether CR using lumbar-type hybrid assistive limb (HAL; lumbar HAL-CR) therapy improves physical functions in hospitalized aged HF patients. Methods and Results: Decompensated and hospitalized HF patients were recruited from 2018 to 2019. As soon as possible after the decompensated HF phase, during the same hospitalization, participants underwent 40-min daily sessions of sit-to-stand and squat exercises with the lumbar-type HAL (lumbar HAL-CR program). The outcome measure was the score on the Short Physical Performance Battery (SPPB) before and after lumbar HAL-CR therapy. Twenty-eight HF patients (median age 84.5 years; 18 males) were enrolled. The median number of lumbar HAL-CR therapy sessions was 5.0. The SPPB score (7.0 [5.3-8.8] to 9.0 [7.0-11.0] points; P<0.001) and quadriceps isometric strength (0.25 [0.22-0.38] to 0.30 [0.26-0.37] kgf/kg; P=0.040) were significantly improved. Patients with lower nutrition status had more improvement in SPPB score. Conclusions: For the inpatient CR program, lumbar-type HAL therapy improved physical functions in elderly HF patients. Lumbar-type HAL therapy may improve physical functions in aged HF patients within the current short-term period of hospitalization for acute-phase HF.