Improvement in Physical Function After Coronary Artery Bypass Graft Surgery Using a Novel Rehabilitation Intervention: A RANDOMIZED CONTROLLED TRIAL

Abstract

Purpose: Cardiorespiratory and skeletal muscle deconditioning occurs following coronary artery bypass graft surgery and hospitalization. Outpatient, phase 2 cardiac rehabilitation (CR) is designed to remediate this deconditioning but typically does not begin until several weeks following hospital discharge. Although an exercise program between discharge and the start of CR could improve functional recovery, implementation of exercise at this time is complicated by postoperative physical limitations and restrictions. Our objective was to assess the utility of neuromuscular electrical stimulation (NMES) as an adjunct to current rehabilitative care following postsurgical discharge and prior to entry into CR on indices of physical function in patients undergoing coronary artery bypass graft surgery.

Methods: Patients were randomized to 4 wk of bilateral, NMES (5 d/wk) to their quadriceps muscles or no intervention (control). Physical function testing was performed at hospital discharge and 4 wk post-discharge using the Short Physical Performance Battery and the 6-min walk tests. Data from 37 patients (19 control/18 NMES) who completed the trial were analyzed. The trial was registered at ClinicalTrials.gov (NCT03892460).

Results: Physical function measures improved from discharge to 4 wk post-surgery across our entire cohort (P < .001). Patients randomized to NMES, however, showed greater improvements in 6-min walk test distance and power output compared with controls (P < .01).

Conclusion: Our results provide evidence supporting the utility of NMES to accelerate recovery of physical function after coronary artery bypass graft surgery.

Conflict of interest statement

The authors declare no conflicts of interest.

Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.

Figures

Figure 1.

Consolidated Standards for Reporting Trials (CONSORT) flow diagram. NMES, neuromuscular electrical stimulation; PPM, permanent pacemaker; ICD, implanted cardioverter defibrillator.

Figure 2:

Short physical performance battery (SPPB) test results, including total score and balance, gait and chair stand component scores for volunteers randomized to control (n=19) or NMES (n=18) interventions at hospital discharge (open bar) and 1-mo post-discharge (filled bar). Data represent mean ± SE. T, time effect; G x T, group by time interaction effect. a, P<.001.

Figure 3.

Six-minute walk test (6MWT) results, including walk distance and power output for volunteers randomized to control (n=19) or NMES (n=18) interventions at hospital discharge (open bar) and 1-mo post-discharge (filled bar). Data represent mean ± SE. T, time effect; G x T, group by time interaction effect. a, P<.001; b, P≤.01.