Cardiac rehabilitation improves functional capacity and patient-reported health status in patients with continuous-flow left ventricular assist devices: the Rehab-VAD randomized controlled trial.

OBJECTIVES: This study examined the effects of a cardiac rehabilitation (CR) program on functional capacity and health status (HS) in patients with newly implanted left ventricular assist devices (LVADs). BACKGROUND: Reduced functional capacity and HS are independent predictors of mortality in patients with heart failure. CR improves both, and is related to improved outcomes in patients with heart failure; however, there is a paucity of data that describe the effects of CR in patients with LVADs. METHODS: Enrolled subjects (n = 26; 7 women; age 55 ± 13 years; ejection fraction 21 ± 8%) completed a symptom-limited cardiopulmonary exercise test, the Kansas City Cardiomyopathy Questionnaire (KCCQ), a 6-min walk test (6MW), and single-leg isokinetic strength test before 2:1 randomization to CR versus usual care. Subjects in the CR group underwent 18 visits of aerobic exercise at 60% to 80% of heart rate reserve. Within-group changes from baseline to follow-up were analyzed with a paired t-test, whereas an independent t-test was used to determine differences in the change between groups. RESULTS: Within-group improvements were observed in the CR group for peak oxygen uptake (10%), treadmill time (3.1 min), KCCQ score (14.4 points), 6MW distance (52.3 m), and leg strength (17%). Significant differences among groups were observed for KCCQ, leg strength, and total treadmill time. CONCLUSIONS: Indicators of functional capacity and HS are improved in patients with continuous-flow LVADs who attend CR. Future trials should examine the mechanisms responsible for these improvements, and if such improvements translate into improved clinical outcomes. (Cardiac Rehabilitation in Patients With Continuous Flow Left Ventricular Assist Devices:Rehab VAD Trial [RehabVAD]; NCT01584895).

Muscular strength and cardiorespiratory fitness are associated with health status in patients with recently implanted continuous-flow LVADs.

INTRODUCTION: Patient health status (PHS) and peak oxygen uptake (V.O2) are important predictors of clinical outcomes in individuals with heart failure. Preliminary studies of individuals with left ventricular assist devices (LVADs) show improvements in both PHS and peak V.O2. However, the relationship between peak V.O2 and PHS in this population is not well described. Likewise, data regarding muscular strength are also lacking in this population. We sought to describe the association between peak V.O2, muscular strength, and PHS in patients with continuous-flow LVADs. METHODS: Subjects (n = 26; 7 women) completed a symptom-limited graded exercise test within an average of 82 days (range, 33-167 days) of LVAD implant. In addition, subjects underwent a 6-Minute Walk Test and an isokinetic knee extension strength test and completed the Kansas City Cardiomyopathy Questionnaire (KCCQ). Spearman correlation coefficients were performed, adjusting for body weight and gender, to examine relationships between variables. RESULTS: Muscular strength, as measured by peak torque, and peak V.O2 were both moderately associated with the KCCQ (r = 0.58, P = .006; r = 0.51, P = .019). A subanalysis revealed that muscular strength and peak V.O2 were related to different domains within the KCCQ. CONCLUSIONS: Leg muscle strength and peak V.O2 appear to be important factors related to PHS in patients with continuous-flow LVADs. This is likely partially a result of deconditioning due to recent hospitalization, as well as persistent heart failure-related peripheral maladaptations in skeletal muscle. Incorporating both a cardiovascular as well as strength training program before and after LVAD implant surgery may be beneficial.