Exercise training combined with electromyostimulation in the rehabilitation of patients with chronic heart failure: A randomized trial.

AIM: Both aerobic training (AT) and electromyostimulation (EMS) of leg muscles improve exercise tolerance in patients suffering from chronic heart failure (CHF). It was speculated that combination of both methods might have an additive effect. This study was performed to evaluate the effects of a combination of AT and EMS in rehabilitation (RHB) of CHF patients. PATIENTS AND METHODS: Patients (n=71; age 59 ± 10.2 yrs, NYHA II/III, EF 32 ± 7.1%) were randomized into 3 groups: a) group AT, b) group EMS, and c) group AT+EMS. AT protocol included standard activity on bicycle 3x a week at the level of individual anaerobic threshold. EMS (10 Hz, mode 20s "on"/20s "off") was applied to leg extensors for 2 h/day. Total time of given type of RHB was 12 weeks. RESULTS: Data analysis revealed statistically significant improvements of patients in all experimental groups (averaged difference after 12 weeks of exercise as related to initial value: ∆VO2peak: +12.9%, ∆VO2AT: +9.3%, ∆Wpeak: +22.7%). No statistically significant difference among experimental groups was found. Quality of life (Minnesota Living with Heart Failure - MLHF) global score was significantly improved in all 3 groups: AT (∆MLHF: -27.9%; P=0.001), AT+EMS (∆MLHF: -29.1%; P=0.002), and EMS (∆MLHF: -16.6%; P=0.008). MLHF score in EMS group showed the smallest time-related improvement compared to AT and AT+EMS groups, and this difference in improvement between the groups was statistically significant (P=0.021). CONCLUSION: No significant difference was found between the two types of exercise training.and nor did, their combination have any significant additional improvement.

Effects of neuromuscular electrical stimulation and aerobic exercise training on arterial stiffness and autonomic functions in patients with chronic heart failure.

Neuromuscular electrical stimulation (NMES) of leg muscles has been introduced in clinical practice as a rehabilitation (RHB) method in patients with chronic heart failure (CHF); however, the role of NMES on the reduction of arterial stiffness and autonomic disbalance in these patients has not yet been studied. Sixty-one patients with stable CHF (mean age 58.9 [2.1] years; mean ejection fraction 31 [4.2]%, New York Heart Association II-III) were randomly assigned into two groups. Patients in (i) exercise training group (ET; n = 30) underwent 12 weeks of bicycle ET (3 × 40 min/week); (ii) group NMES (n = 31) performed 12 weeks of NMES of quadriceps and calf muscles (frequency 10 Hz, mode "20 s on-20 s off," intensity 60 mA), 2 × 60 min/day. Noninvasive assessment of arterial stiffness was done using the cardio-ankle vascular index (CAVI). CAVI and heart rate variability (HRV) and ·VO(2peak) were evaluated before and after RHB program. Both types of RHB reduced significantly CAVI (ET from 9.6 [0.2] to 8.9 [0.2], P < 0.012; NMES from 9.3 [0.2] to 8.7 [0.2], P < 0.013), increased high frequency (HF) component of HRV (+65.6%; P = 0.001) and decreased ratio of low frequency (LF) component with HF component (LF/HF ratio) in group ET (-39.8%; P < 0.001). Changes of HRV parameters in group NMES were not significant; however, a marked tendency to autonomic stabilization was present. Both types of RHB led also to significant increase of ·VO(2peak) (ET from 18.7 [0.7] to 20.8 [0.7] mL/kg/min, P < 0.004; NMES from 17.3 [0.7] to 19.0 [0.7] mL/kg/min, P < 0.001). ET or NMES has been shown to improve significantly arterial stiffness and to stabilize autonomic balance.

Intra-dialytic electrostimulation of leg extensors may improve exercise tolerance and quality of life in hemodialyzed patients.

Hemodialyzed (HD) patients with end-stage renal disease (ESRD) exhibit lower fitness as a consequence of chronic uremic changes that trigger various structural, metabolic, and functional abnormalities in skeletal muscles. The aim of this randomized study was to compare the effect of rehabilitation (RHB) training on a bicycle ergometer and electromyostimulation (EMS) of leg extensors in HD patients with ESRD. Thirty-two HD patients (18 men/14 women; mean age 61.1 ± 8.8 years) were randomized into three groups: (i) exercise training (ET; n = 11) on bicycle ergometer 2 × 20 min; (ii) EMS (n = 11) where stimulation (10 Hz) of leg extensors was applied for 60 min; and (iii) controls (CON; n = 10) without exercise. Exercising was performed between the 2nd and the 3rd hour of HD, three times a week, 20 weeks in total. Ergometric test was performed in order to evaluate peak workload (W(peak)), 6-min corridor walking test (CWT) to evaluate the distance walked, and dynamometry of leg extensors to assess muscle power (F(max)). Urea clearance was monitored and expressed as standard parameters: spKt/V, spKt/V equilibrated (spKt/V-e), and the urea removal ratio (URR). Quality of life (QoL) was assessed by the questionnaire SF-36. A significant increase of F(max) (P = 0.040 in group ET; P = 0.032 in group EMS), of 6-min CWT (P < 0.001 in ET group; P = 0.042 in EMS group), and of W(peak) (P = 0.041 in ET group) was observed. In both exercising groups, significant increase of spKt/V, spKt/V-e, and URR was found as compared with initial values (P < 0.05). In both exercising groups, highly significant changes in summarized mental functions were found (P = 0.001); in summarized physical components, significant improvement was observed in the ET group (P = 0.006). Intradialytic RHB showed comparable positive effects on functional parameters, urea clearance, and QoL. Intradialytic EMS might represent wide therapeutic possibility in the near future.