Low-Frequency Electrical Stimulation Increases Muscle Strength and Improves Blood Supply in Patients With Chronic Heart Failure

Handcycling with concurrent lower body low-frequency electromyostimulation significantly increases acute oxygen uptake in elite wheelchair basketball players: an acute crossover trial

OBJECTIVE

Wheelchair basketball (WCB) demands high-intensity training due to its intermittent nature. However, acute oxygen uptake (V˙O2) in handcycling is restricted. Combining handcycling with low-frequency electromyostimulation (LF-EMS) may enhance V˙O2 in elite WBC athletes.

DESIGN

Randomized crossover trail.

SUBJECTS

Twelve German national team WCB players (age: 25.6 [5.6] years, height: 1.75 [0.16] m, mass: 74.0 [21.7] kg, classification: 2.92 [1.26]).

METHOD

Participants underwent 2×5 min of handcycling (60 rpm, ¾ bodyweight resistance in watts) (HANDCYCLE) and 2×5 min of handcycling with concurrent LF-EMS (EMS_HANDCYCLE). LF-EMS (4Hz, 350µs, continuous stimulation) targeted gluteal, quadriceps, and calf muscles, adjusted to individual pain thresholds (buttocks: 69.5 [22.3] mA, thighs: 66.8 [20.0] mA, calves: 68.9 [31.5] mA).

RESULTS

Significant mode-dependent differences between HANDCYCLE and EMS_HANDCYCLE were found in V˙O2 (17.60 [3.57] vs 19.23 [4.37] ml min-1 kg-1, p = 0.001) and oxygen pulse (16.69 [4.51] vs 18.41 [5.17] ml, p = 0.002). ΔLactate was significantly lower in HANDCYCLE (0.04 [0.28] vs 0.31 [0.26] mmol l-1). Although perceived effort did not differ (p = 0.293), discomfort was rated lower in HANDCYCLE (1.44 [1.28] vs 3.94 [2.14], p = 0.002).

CONCLUSION

LF-EMS applied to the lower extremities increases oxygen demand during submaximal handcycling. Thus, longitudinal application of LF-EMS should be investigated as a potential training stimulus to improve aerobic capacity in wheelchair athletes.

Case report of belt electrode-skeletal muscle electrical stimulation for acute heart failure with severe obesity: a novel therapeutic option for acute phase rehabilitation

Background

Belt electrode skeletal muscle electrical stimulation (B-SES) is an emerging therapy anticipated to yield more favorable outcomes than conventional neuromuscular electrical stimulation (NMES), owing to its larger stimulation area. However, information on its efficacy and safety in patients with heart failure remains limited.

Case presentation

A 43-year-old man with a body mass index of 41 kg/m2 was admitted to our hospital for acute heart failure due to dilated cardiomyopathy. The patient required prolonged catecholamine support owing to poor cardiac function, and heart transplantation was considered. We initiated a mobilization program, but the patient's mobility was highly limited due to severe obesity and symptomatic orthostatic hypotension. B-SES was introduced to accomplish weight loss and early ambulation. We applied an intensive monitoring program for safe use and modulated the intensity of B-SES according to physical function. During the B-SES program, the patient's body weight decreased from 89.6 kg to 78.6 kg. Sequential evaluations of body composition and skeletal muscle ultrasonography revealed improved muscle mass, quality, and physical function. Furthermore, we explored the workload of B-SES using expiratory gas analysis. No adverse events were observed during B-SES.

Discussion

We successfully used B-SES to improve muscle function and morbidity in the treatment of acute heart failure. B-SES could be an option for patients with heart failure who have limited mobility and obesity.

Relationship Between Increased Oxygen Uptake and Lactate Production With Progressive Incremental Electrode Skeletal Muscle Stimulation: A Pilot Study

Background Belt electrode skeletal muscle stimulation (B-SES) is an alternative exercise therapy for those with difficulty performing voluntary exercise. However, it is unknown whether oxygen uptake (VO2) in B-SES is comparable to cardiopulmonary exercise test (CPX) as assessed by voluntary exercise. This study aimed to evaluate oxygen uptake (VO2) and lactate (LA) production in incremental B-SES compared to ergometer CPX and to determine the relationship with ergometer CPX. Methods This study included 10 healthy young Japanese participants. Using a crossover design, all participants underwent incremental B-SES CPX and ergometer CPX using a 20 W ramp. Serum lactic acid concentration (LA) was measured serially before, during, and after B-SES. The tolerability of B-SES was adjusted with the change in LA level (⊿LA). Results Peak VO2 during B-SES (14.1±3.3 mL/kg/min) was significantly lower than ergometer peak VO2 (30.2±6.2 mL/kg/min, P<0.001). B-SES peak VO2 was similar to the anaerobic threshold (AT) VO2 on ergometer CPX (15.1±2.6 mL/kg/min). LA (Rest: 1.4±0.3, Peak: 2.8±0.8 mmol) and plasma noradrenalin (Rest: 0.2±0.1, Peak: 0.4±0.1 ng/mL) levels increased after B-SES. No significant correlation was observed between B-SES peak VO2 and ergometer CPX. However, after adjusting for B-SES, tolerability, it (peak VO2 of B-SES /⊿LA) correlated with peak VO2 (r=0.688, p=0.028) on the ergometer. Conclusion Peak VO2 of the passively progressive B-SES almost reached the AT value of the ergometer CPX without adverse events. Peak VO2 of B-SES adjusted with ⊿LA may be used to predict peak VO2 in ergometer CPX.

Effects of Home-Based Electrical Stimulation on Plasma Cytokines Profile, Redox Biomarkers, and Metalloproteinases in the Heart Failure with Reduced Ejection Fraction: A Randomized Trial

Background: Low-frequency electrical stimulation (LFES) is an adjuvant method for heart failure (HF) patients with restrictions to start an exercise. However, the impact on molecular changes in circulating is unknown. We investigated the effects of 10 weeks of home-based LFES on plasma cytokines profile, redox biomarkers, metalloproteinases (MMPs) activity, and exercise performance in HF patients. Methods: Twenty-four HF patients (52.45 ± 9.15 years) with reduced ejection fraction (HFrEF) (EF < 40%), were randomly assigned to a home-based LFES or sham protocol. Plasma cytokines profile was assessed through interleukins, interferon-gamma, and tumor necrosis factor levels. Oxidative stress was evaluated through ferric reducing antioxidant power, thiobarbituric acid-reactive substances, and inducible nitric oxide synthase. The MMPs activity were analyzed by zymography. Cardiorespiratory capacity and muscle strength were evaluated by cardiopulmonary test and isokinetic. Results: LFES was able to increase the active-MMP2 activity post compared to pre-training (0.057 to 0.163, p = 0.0001), while it decreased the active-MMP9 (0.135 to 0.093, p = 0.02). However, it did not elicit changes in cytokines, redox biomarkers, or exercise performance (p > 0.05). Conclusion: LFES protocol is a promising intervention to modulate MMPs activity in HFrEF patients, although with limited functional effects. These preliminary responses may help the muscle to adapt to future mechanical demands dynamically.

In-hospital electrical muscle stimulation for patients early after heart failure decompensation: results from a prospective randomised controlled pilot trial

Background

Electrical muscle stimulation (EMS) is being evaluated as a possible alternative to exercise training to improve functional capacity in severely deconditioned patients with heart failure (HF). However, there is insufficient data on delayed effects of EMS starting early after decompensation. The aim of this study was to determine the impact of a short inpatient EMS intervention in severely deconditioned patients with HF on functional capacity and quality of life (QoL) over a follow-up period of 1 month.

Methods

This is a prospective randomised sham-controlled pilot study. 45 patients hospitalised for decompensated systolic HF (58% men, mean age 66.4±10.2 years) were randomised to EMS (n=22) or sham stimulation (n=23) of lower limbs starting within 3 days after admission. The intervention included 7–10 sessions lasting from 30 to 90 min. The 6-minute walking test distance (6-MWTD), Duke Activity Status Index (DASI) and Minnesota Living with Heart Failure Questionnaire (MLHFQ) were evaluated at baseline, discharge and after 1 month.

Results

All patients completed the programme with good EMS tolerance. 37 patients were included in the final analysis. At discharge, 6-MWTD improved from 206,1±61,3 to 299.5±91 m, DASI from 12.1±5.6 to 18.3±7.2 and MLHFQ from 55.6±8.5 to 34.2±9 with EMS compared with smaller improvements in the sham group (p<0.05 for all). One month after discharge, improvements in the EMS group remained significant for MLHFQ (p=0.004) and DASI (p=0.042) and statistically non-significant for 6-MWTD compared with the sham group.

Conclusions

Short-term in-hospital EMS leads to improvements in functional capacity and QoL in selected patients early after HF decompensation that are retained over 1 month after discharge and therefore may serve as initial intervention to improve physical capacity or as a bridge to further conventional exercise training. Larger studies are required to evaluate individual responses to an early initiation of EMS in decompensated HF as well as long-term effects.

Handcycling with concurrent lower body low-frequency electromyostimulation significantly increases acute oxygen uptake: implications for rehabilitation and prevention

Background

Acute increases in exercise-induced oxygen uptake (V̇O₂) is crucial for aerobic training adaptations and depends on how much muscle mass is involved during exercising. Thus, handcycling is per se limited for higher maximal oxygen uptakes (V̇O₂max) due to restricted muscle involvement. Handcycling with additional and simultaneous application of low-frequency electromyostimulation (EMS) to the lower extremities might be a promising stimulus to improve aerobic capacity in disabled and rehabilitative populations.

Method

Twenty-six healthy young adults (13 female, age: 23.4 ± 4.5 years, height: 1.77 ± 0.09 m, mass: 71.7 ± 16.7 kg) completed 4 ×10 minutes of sitting (SIT), sitting with concurrent EMS (EMS_SIT), handcycling (60 rpm, 1/2 bodyweight as resistance in watts) (HANDCYCLE) and handcycling with concurrent EMS of the lower extremities (EMS_HANDCYCLE). During EMS_SIT and EMS_HANDCYCLE, low frequency EMS (impulse frequency: 4Hz, impulse width: 350 µs, continuous stimulation) was applied to gluteal, quadriceps and calf muscles. The stimulation intensity was selected so that the perceived pain could be sustained for a duration of 10 minutes (gluteus: 80.0 ± 22.7 mA, quadriceps: 94.5 ± 20.5 mA, calves: 77.5 ± 19.1 mA).

Results

Significant mode-dependent changes of V̇O₂ were found (p < 0.001, η _p ² = 0.852). Subsequent post-hoc testing indicated significant difference between SIT vs. EMS_SIT (4.70 ± 0.75 vs. 10.61 ± 4.28 ml min^-1 kg^-1, p < 0.001), EMS_SIT vs. HANDCYCLE (10.61 ± 4.28 vs. 13.52 ± 1.40 ml min^-1 kg^-1, p = 0.005), and between HANDCYCLE vs. EMS_HANDCYCLE (13.52 ± 1.40 vs. 18.98 ± 4.89 ml min^-1 kg^-1, p = 0.001).

Conclusion

Handcycling with simultaneous lower body low-frequency EMS application elicits notably higher oxygen uptake during rest and moderately loaded handcycling and may serve as an additional cardiocirculatory training stimuli for improvements in aerobic capacity in wheelchair and rehabilitation settings.

Influence of surface peripheral electrical stimulation on nerve regeneration after digital nerve neurorrhaphy: study protocol for a randomized clinical trial

We will study the influence of low intensity and frequency surface peripheral electrical stimulation (PES) on nerve regeneration of digital nerve injuries of the hand after its surgical repair in humans. Participants will be patients with acute traumatic peripheral nerve injury referred to the Hand Surgery Service of the General Hospital of the State of Bahia, a reference service in the state. These patients will undergo surgery followed by PES in the immediate postoperative period. After hospital discharge, they will be followed up on an outpatient basis by researchers, who will remotely supervise a physiotherapy program. Our hypothesis is that PES will positively influence the recovery of sensory function in patients undergoing neurorrhaphy of digital nerves of the hand.

ReBEC registration:  U1111-1259-1998 (12/18/2020)

Real-world experience of feasibility and efficacy of electrical muscle stimulation in elderly patients with acute heart failure: A randomized controlled study

BACKGROUND

Reduced aerobic capacity and deconditioning contributes to morbidity and mortality in elderly acute heart failure (AHF) patients. Electrical muscle stimulation (EMS) has shown to be a suitable alternative to exercise in AHF. However, feasibility and efficacy are unknown in a real-world setting.

METHODS

This is a prospective, open label blinded, randomized, controlled study, investigating feasibility and efficacy of high-intensity versus low-intensity EMS versus controls in elderly AHF patients. Patients and investigators were blinded to the intervention. EMS was offered to > 60 years old AHF patients, initiated during hospitalization and continued at home. Outcome measures included changes in 6-min walking test distance (6-MWTD), functional capacity and quality-of-life at 3 and 6 weeks.

RESULTS

Among 97 consecutive AHF patients (78.1 ± 9.4 years, 42.3% females), 60 (61.9%) were eligible for EMS. Of these, 27 provided written informed consent and were randomly assigned to high-intensity (n = 10), low-intensity EMS (n = 9) and controls (n = 8). 13/27 completed the intervention. Main reason for dropouts was intolerance of the overall intervention burden. MACE occurred in 5 and were not associated with the study. EMS groups showed significant improvement of 6-MWTD (controls vs low-intensity p = 0.018) and of independence in daily living (for both p < 0.05).

CONCLUSIONS

Changes in 6-MWTD suggest efficacy of EMS. Whereas all tolerated EMS well, the burden of study intervention was too high and resulted in a consent rate of <50% and high dropouts, which limit the interpretability of our data. Less demanding EMS protocols are required to evaluate the full potential of EMS in elderly AHF patients.

Effect of early cardiac rehabilitation on prognosis in patients with heart failure following acute myocardial infarction

Objective

The purpose of this retrospective study is to evaluate the effectiveness of early cardiac rehabilitation on patients with heart failure following acute myocardial infarction.

Methods

Two hundred and thirty-two patients who developed heart failure following acute myocardial infarction were enrolled in this study. Patients were divided into heart failure with reduced ejection fraction group (n = 54) and heart failure with mid-range ejection fraction group (n = 178). Seventy-eight patients who accepted a two-week cardiac rehabilitation were further divided into two subgroups based on major adverse cardiovascular events. Key cardio-pulmonary exercise testing indicators that may affect the prognosis were identified among the cardiac rehabilitation patients.

Results

Early cardiac rehabilitation significantly reduced cardiac death and re-hospitalization in patients. There was more incidence of diabetes, hyperkalemia and low P_ETCO₂ in the cardiac rehabilitation group who developed re-hospitalization. Low P_ETCO₂ at anaerobic threshold (≤ 33.5 mmHg) was an independent risk factor for re-hospitalization.

Conclusions

Early cardiac rehabilitation reduced major cardiac events in patients with heart failure following acute myocardial infarction. The lower P_ETCO₂ at anaerobic threshold is an independent risk factor for re-hospitalization, and could be used as a evaluating hallmark for early cardiac rehabilitation.

Effects of whole-body neuromuscular electrical stimulation device on hemodynamics, arrhythmia, and sublingual microcirculation

Neuromuscular electrical stimulation has been used to treat cardiovascular diseases and other types of muscular dysfunction. A novel whole-body neuromuscular electrical stimulation (WB-NMES) wearable device may be beneficial when combined with voluntary exercises. This study aimed to investigate the safety and effects of the WB-NMES on hemodynamics, arrhythmia, and sublingual microcirculation. The study included 19 healthy Japanese volunteers, aged 22-33 years, who were not using any medication. Electrocardiogram (ECG), echocardiography, and blood sampling were conducted before a 20-min WB-NMES session and at 0 and 10 min after termination of WB-NMES. Their tolerable maximum intensity was recorded using numeric rating scale. Arrhythmia was not detected during neuromuscular electrical stimulation or during 10 min of recovery. Blood pressure, heart rate, left ventricular ejection fraction, and diastolic function remained unchanged; however, mild mitral regurgitation was transiently observed during WB-NMES in a single male participant. A decrease in blood glucose and an increase in blood lactate levels were observed, but no changes in blood fluidity, sublingual microcirculation, blood levels of noradrenaline, or oxidative stress were shown. WB-NMES is safe and effective for decreasing blood glucose and increasing blood lactate levels without changing the blood fluidity or microcirculation in healthy people.

Satellite cell proliferation and myofiber cross-section area increase after electrical stimulation following sciatic nerve crush injury in rats

BACKGROUND

Electrical stimulation has been recommended as an effective therapy to prevent muscle atrophy after nerve injury. However, the effect of electrical stimulation on the proliferation of satellite cells in denervated muscles has not yet been fully elucidated. This study was aimed to evaluate the changes in satellite cell proliferation after electrical stimulation in nerve injury and to determine whether these changes are related to the restoration of myofiber cross-section area (CSA).

METHODS

Sciatic nerve crush injury was performed in 48 male Sprague-Dawley rats. In half (24/48) of the rats, the gastrocnemius was electrically stimulated transcutaneously on a daily basis after injury, while the other half were not stimulated. Another group of 24 male Sprague-Dawley rats were used as sham operation controls without injury or stimulation. The rats were euthanized 2, 4, and 6 weeks later. After 5-bromo-2'-deoxyuridine (BrdU) labeling, the gastrocnemia were harvested for the detection of paired box protein 7 (Pax7), BrdU, myofiber CSA, and myonuclei number per fiber. All data were analyzed using two-way analysis of variance and Bonferroni post-hoc test.

RESULTS

The percentages of Pax7-positive nuclei (10.81 ± 0.56%) and BrdU-positive nuclei (34.29 ± 3.87%) in stimulated muscles were significantly higher compared to those in non-stimulated muscles (2.58 ± 0.33% and 1.30 ± 0.09%, respectively, Bonferroni t = 15.91 and 18.14, P < 0.05). The numbers of myonuclei per fiber (2.19 ± 0.24) and myofiber CSA (1906.86 ± 116.51 μm) were also increased in the stimulated muscles (Bonferroni t = 3.57 and 2.73, P < 0.05), and both were positively correlated with the Pax7-positive satellite cell content (R = 0.52 and 0.60, P < 0.01). There was no significant difference in the ratio of myofiber CSA/myonuclei number per fiber among the three groups.

CONCLUSIONS

Our results indicate that satellite cell proliferation is promoted by electrical stimulation after nerve injury, which may be correlated with an increase in myonuclei number and myofiber CSA.

Chronic neuromuscular electrical stimulation improves muscle mass and insulin sensitivity in a mouse model

Muscle wasting reduces functional capacity and increases cardiometabolic risk in chronic disease. Neuromuscular electrical stimulation (NMES) of the lower limb has been shown to reverse muscle wasting in these patients but its effect on cardiometabolic health is unclear. We investigated a mouse model of in-vivo non-invasive chronic NMES on muscle mass, insulin sensitivity and arterial blood pressure (BP). Twenty-three C57BL6 mice underwent unilateral NMES or sham training over 2.5 weeks while anesthetized by isoflurane. Lower limb muscle mass and the stimulated limb to non-stimulated limb muscle mass ratio were compared between groups (NMES vs. sham). Insulin sensitivity was assessed 48 h after training using an intraperitoneal insulin tolerance test (ITT) and BP was assessed before and after training using the tail-cuff technique. After training, muscle mass increased in NMES vs. sham (416 ± 6 vs. 397 ± 6 mg, p = 0.04) along with the ratio of muscle mass (+3 ± 1% vs. −1 ± 1% p = 0.04). Moreover, insulin sensitivity improved in NMES vs. sham (average blood glucose during ITT: 139.6 ± 8.5 vs. 161.9 ± 9.0 mg/dl blood, p = 0.01). BP was decreased in both groups, although it is likely that the effect of NMES on BP was dampened by repetitive anesthesia. The metabolic benefit of NMES training could be of great utility in patients with chronic disease. Moreover, the clinical-like mouse model of NMES is an effective tool to investigate the systemic effects of local muscle strengthening.

Early mobilization for mechanically ventilated patients in the intensive care unit: a systematic review and meta-analysis

Background

Early mobilization (EM) is a regimen that was carried out by physiotherapists in a relatively early stage. It has been investigated by an increasing number of researchers. However, there has not been a meta-analysis concerning whether EM could benefit the clinical outcomes of critically ill patients requiring mechanical ventilation (MV). The present systematic review aims to evaluate the effect of EM compared with immobilization for mechanically ventilated patients.

Methods

A computerized literature search was performed in six databases for related articles from inception to June 2017. We included randomized controlled trials and controlled clinical trials and used the Physiotherapy Evidence Database scale to assess the quality of included studies. Primary outcomes were measures of muscle function, duration of MV, and incidence of mortality. Secondary outcomes were adverse effects and length of stay (LOS) in intensive care unit (ICU) and hospital.

Results

Eight trials were included; of those, only one study without standard EM reported that the intervention was invalid to improve the outcomes. The result of meta-analysis indicated that EM shortened the duration of MV; however, it had no positive effect on mortality and LOS in ICU.

Conclusions

This review suggests that EM improves the muscle function and ventilation duration. Further research highlighting standard intervention and specific groups is needed.

Exercise-Based Cardiac Rehabilitation with and Without Neuromuscular Electrical Stimulation and its Effect on Exercise Tolerance and Life Quality of Persons with Chronic Heart Failure

The study compares the effect of an exercise-based cardiac rehabilitation program with a program combining physical exercise and lower extremity neuromuscular electrical stimulation (NMES) on the recovery of patients with chronic heart failure (CHF) with NYHA II-III symptoms. Seventy two patients with stable CHF were randomly distributed to four groups that received exercise-based cardiac rehabilitation and pharmacological treatment. Groups I and II were additionally administered NMES (35 Hz and 10 Hz, respectively) and in Group III sham NMES was applied. Group IV (controls) received solely pharmacological and exercise treatment. Exercise tolerance and quality of life were assessed in patients pre-treatment and at week 3. Three weeks of rehabilitation induced significant increases (p < 0.05) in the distance covered in the 6-minute walk test, the metabolic equivalent (MET), the duration of the treadmill exercise stress test, the left ventricle ejection fraction (LVEF) and improved quality of life in all groups, but between-group differences were not significant (p > 0.05). In none of the groups were the left ventricle end-systolic and end-diastolic diameters (mm) measured at week 3 significantly different from their baseline values (p > 0.05). Exercise-based cardiac rehabilitation contributed to higher exercise tolerance, LVEF and quality of life of CHF patients (NYHA II-III), contrary to cardiac rehabilitation combined with lower extremity NMES (35 Hz and 10 Hz) that failed to induce such improvements. More research is necessary to assess the therapeutic efficacy of NMES applied to CHF patients with NYHA IV symptoms.

Feasibility and effects of intra-dialytic low-frequency electrical muscle stimulation and cycle training: A pilot randomized controlled trial

Background and objectives

Exercise capacity is reduced in chronic kidney failure (CKF). Intra-dialytic cycling is beneficial, but comorbidity and fatigue can prevent this type of training. Low–frequency electrical muscle stimulation (LF-EMS) of the quadriceps and hamstrings elicits a cardiovascular training stimulus and may be a suitable alternative. The main objectives of this trial were to assess the feasibility and efficacy of intra-dialytic LF-EMS vs. cycling

Design, setting, participants, and measurements

Assessor blind, parallel group, randomized controlled pilot study with sixty-four stable patients on maintenance hemodialysis. Participants were randomized to 10 weeks of 1) intra-dialytic cycling, 2) intra-dialytic LF-EMS, or 3) non-exercise control. Exercise was performed for up to one hour three times per week. Cycling workload was set at 40–60% oxygen uptake (VO₂) reserve, and LF-EMS at maximum tolerable intensity. The control group did not complete any intra-dialytic exercise. Feasibility of intra-dialytic LF-EMS and cycling was the primary outcome, assessed by monitoring recruitment, retention and tolerability. At baseline and 10 weeks, secondary outcomes including cardio-respiratory reserve, muscle strength, and cardio-arterial structure and function were assessed.

Results

Fifty-one (of 64 randomized) participants completed the study (LF-EMS = 17 [77%], cycling = 16 [80%], control = 18 [82%]). Intra-dialytic LF-EMS and cycling were feasible and well tolerated (9% and 5% intolerance respectively, P = 0.9). At 10-weeks, cardio-respiratory reserve (VO_{2 peak}) (Difference vs. control: LF-EMS +2.0 [95% CI, 0.3 to 3.7] ml.kg^-1.min^-1, P = 0.02, and cycling +3.0 [95% CI, 1.2 to 4.7] ml.kg^-1.min^-1, P = 0.001) and leg strength (Difference vs. control: LF-EMS, +94 [95% CI, 35.6 to 152.3] N, P = 0.002 and cycling, +65.1 [95% CI, 6.4 to 123.8] N, P = 0.002) were improved. Arterial structure and function were unaffected.

Conclusions

Ten weeks of intra-dialytic LF-EMS or cycling improved cardio-respiratory reserve and muscular strength. For patients who are unable or unwilling to cycle during dialysis, LF-EMS is a feasible alternative.

Low frequency electrical muscle stimulation and endothelial function in advanced heart failure patients

Aim

Obtain initial estimates of the change in brachial artery endothelial function and maximal oxygen uptake (VO_2peak) with 8 weeks of low‐frequency electrical muscle stimulation (LF‐EMS) or sham in patients with advanced chronic heart failure.

Methods and results

Using a double blind, randomized design, 35 patients with chronic heart failure (New York Heart Association class III–IV) were assigned to 8 weeks (5 × 60 min per week) of either LF‐EMS (4 Hz, continuous) or sham (skin level stimulation only) of the quadriceps and hamstrings muscles. Four of the five sessions were at home and one under supervision. Ultrasound images of resting brachial artery diameter and post 5 min occlusion to determine flow‐mediated dilation (FMD), a marker of vascular function and peak oxygen uptake (VO_2peak) during cardiopulmonary exercise test, were measured before and after LF‐EMS (n = 20) and sham (n = 15) interventions. FMD improved by 2.56% (95% confidence interval: 0.69 to 3.80) with LF‐EMS compared with sham (P = 0.07). There were no notable changes in VO_2peak.

Conclusions

Improvements in FMD with LF‐EMS may have a clinically meaningful effect as higher FMD is associated with better prognosis. This is a preliminary finding, and a larger trial is warranted.

Effects of training intensity in electromyostimulation on human skeletal muscle

PURPOSE

High-intensity neuromuscular electrical stimulation (NMES) training can induce muscle hypertrophy at the whole muscle and muscle fiber levels. However, whether low-intensity NMES training has a similar result is unknown. This study aimed to investigate whether low-intensity NMES training could elicit muscle hypertrophy at the whole muscle and muscle fiber levels in the human skeletal muscle.

METHODS

Eight untrained young males were subjected to 18 min of unilateral NMES training for 8 weeks. One leg received NMES at maximal tolerable intensity (HIGH); the other leg received NMES at an intensity half of that in the HIGH condition (LOW). Quadriceps muscle thickness (MT), muscle fiber cross-sectional area (CSA), and knee extension strength were measured before and after the training period.

RESULTS

The average training intensity throughout the intervention period in the HIGH and LOW conditions were 62.5 ± 4.6% maximal voluntary contraction (MVC) and 32.6 ± 2.6% MVC, respectively. MT, CSA, and muscle strength increased in both exercise conditions (p < 0.05); however, training effects in the LOW condition were lower than those in the HIGH condition (p < 0.05). The average training intensity showed a positive correlation with percent changes in muscle strength (r = 0.797, p = 0.001), MT (r = 0.876, p = 0.001), type I fiber CSA (r = 0.730, p = 0.01), and type II fiber CSA (r = 0.899, p = 0.001).

CONCLUSIONS

Low-intensity NMES could increase MT, muscle fiber CSA, and muscle strength in healthy human skeletal muscles. However, the magnitude of increase is lower in low-intensity than in high-intensity NMES training.

Influence of Electroacupuncture and Laser-Acupuncture on Treating Paresthesia in Patients Submitted to Combined Orthognathic Surgery and Genioplasty

Objective: The goal of this research was to observe the influence of electroacupuncture (EA) and laser-acupuncture on the return of tactile/pain sensitivity in patients who underwent orthognathic surgery. Materials and Methods: Thirty volunteers subjected to orthognathic surgery were evaluated and randomly divided into 2 groups, in which 3 treatments were evaluated: control (n = 30) (G0, medication + placebo laser treatment) and 2 experimental treatments (n = 15) (G1, medication + EA) or G2 (medication + laser-acupuncture). The control group had n = 30 because for each experimental treatment conducted on a volunteer's hemi-face, there was a control treatment on the other hemi-face. In G1, medication was given with EA, with needles placed at predetermined points (ST 4 [Dicang], M-HN-18 [Jiachengjiang], CV 24 [Chengjiang], ST 5 [Daying], ST 6 [Jiache], and point A1 [YNSA]). For electrostimulation, the device used delivered transcutaneous electrical nerve stimulation of a burst type, with intensity and frequency variations of T = 220 ms and F = 4 Hz (30 minutes, 2 × /week). In G2, in addition to the medication, laser irradiation (at 780 nm) was applied on acupuncture points (at 0.04 cm², 70 mW, 6 s/point, 0.42 J/point, 10 J/cm², 2 × /week). All volunteers were evaluated before and during the 4 months following the surgery. Tactile sensitivity was assessed by mechanical brushing (brush #s 2 and 12) and by a 2-point discrimination test, using a bow compass. A pain test was performed with a pulp electrical test that stimulates intact nerves of the dentin-pulp complex. A Kaplan-Meier test was performed, and survival curves were plotted for comparison between groups. Cox regression analysis was also conducted (α = 0.05). Results: There were no statistically significant differences among the groups for the 2-point discrimination test (brushes #2 and #12) on the buccal mucosa region and for the pulp test on all evaluated regions. However, the tactile test using brush #12 revealed significant differences between G1 and the other groups when considering the lower lip (P = 0.024) and chin (P = 0.028) areas. Conclusions: Only EA was able to influence-using the brushing test (brush #12)-the return of tactile sensitivity on the chin and lower lip positively after combined orthognathic surgery and genioplasty.

Randomised feasibility trial into the effects of low-frequency electrical muscle stimulation in advanced heart failure patients

OBJECTIVES

Low-frequency electrical muscle stimulation (LF-EMS) may have the potential to reduce breathlessness and increase exercise capacity in the chronic heart failure population who struggle to adhere to conventional exercise. The study's aim was to establish if a randomised controlled trial of LF-EMS was feasible.

DESIGN AND SETTING

Double blind (participants, outcome assessors), randomised study in a secondary care outpatient cardiac rehabilitation programme.

PARTICIPANTS

Patients with severe heart failure (New York Heart Association class III-IV) having left ventricular ejection fraction <40% documented by echocardiography were eligible.

INTERVENTIONS

Participants were randomised (remotely by computer) to 8 weeks (5×60 mins per week) of either LF-EMS intervention (4 Hz, continuous, n=30) or sham placebo (skin level stimulation only, n=30) of the quadriceps and hamstrings muscles. Participants used the LF-EMS straps at home and were supervised weekly OUTCOME MEASURES: Recruitment, adherence and tolerability to the intervention were measured during the trial as well as physiological outcomes (primary outcome: 6 min walk, secondary outcomes: quadriceps strength, quality of life and physical activity).

RESULTS

Sixty of 171 eligible participants (35.08%) were recruited to the trial. 12 (20%) of the 60 patients (4 LF-EMS and 8 sham) withdrew. Forty-one patients (68.3%), adhered to the protocol for at least 70% of the sessions. The physiological measures indicated no significant differences between groups in 6 min walk distance(p=0.13) and quality of life (p=0.55) although both outcomes improved more with LF-EMS.

CONCLUSION

Patients with severe heart failure can be recruited to and tolerate LF-EMS studies. A larger randomised controlled trial (RCT) in the advanced heart failure population is technically feasible, although adherence to follow-up would be challenging. The preliminary improvements in exercise capacity and quality of life were minimal and this should be considered if planning a larger trial.

TRIAL REGISTRATION NUMBER

ISRCTN16749049.

Effects of combined exercise training and electromyostimulation treatments in chronic heart failure: A prospective multicentre study

Background Exercise training as part of a comprehensive cardiac rehabilitation is recommended for patients with cardiac heart failure. It is a valuable method for the improvement of exercise tolerance. Some studies reported a similar improvement with quadricipital electrical myostimulation, but the effect of combined exercise training and electrical myostimulation in cardiac heart failure has not been yet evaluated in a large prospective multicentre study. Purpose The aim of this study was to determine whether the addition of low frequency electrical myostimulation to exercise training may improve exercise capacity and/or muscular strength in cardiac heart failure patients. Methods Ninety-one patients were included (mean age: 58 ± 9 years; New York Heart Association II/III: 52/48%, left ventricular ejection fraction: 30 ± 7%) in a prospective French study. The patients were randomised into two groups: 41 patients in exercise training and 50 in exercise training + electrical myostimulation. All patients underwent 20 exercise training sessions. In addition, in the exercise training + electrical myostimulation group, patients underwent 20 low frequency (10 Hz) quadricipital electrical myostimulation sessions. Each patient underwent a cardiopulmonary exercise test, a six-minute walk test, a muscular function evaluation and a quality of life questionnaire, before and at the end of the study. Results A significant improvement of exercise capacity (Δ peak oxygen uptake+15% in exercise training group and +14% in exercise training + electrical myostimulation group) and of quality of life was observed in both groups without statistically significant differences between the two groups. Mean creatine kinase level increased in the exercise training group whereas it remained stable in the combined group. Conclusions This prospective multicentre study shows that electrical myostimulation on top of exercise training does not demonstrate any significant additional improvement in exercise capacity in cardiac heart failure patients.

The Effectiveness of Calf Muscle Electrostimulation on Vascular Perfusion and Walking Capacity in Patients Living With Type 2 Diabetes Mellitus and Peripheral Artery Disease

The aim of the study was to explore calf muscle electrostimulation on arterial inflow and walking capacity in claudicants with peripheral artery disease and diabetes mellitus. A prospective, 1-group, pretest-posttest study design was used on 40 high-risk participants (n = 40) who exhibited bilateral limb ischemia (ankle brachial pressure index [ABPI] <0.90), diabetes mellitus, and calf muscle claudication. A program of calf muscle electrical stimulation with varying frequency (1-250 Hz) was prescribed for 1 hour per day for 12 weeks. Spectral waveforms analysis, ABPI, absolute claudication distance (ACD), and thermographic temperature patterns across 4 specified regions of interest (hallux, medial forefoot, lateral forefoot, heel) at rest and after exercise, were recorded at baseline and following intervention to evaluate for therapeutic outcomes. A significant improvement in ACD and ABPI was registered following the intervention ( P = .000 and P = .001, respectively). Resting foot temperatures increased significantly ( P = .000) while the postexercise temperature drops were halved across all regions at follow-up, with hallux ( P = .005) and lateral forefoot ( P = .038) reaching statistical significance. Spectral Doppler waveforms were comparable ( P = .304) between both serial assessments. Electrical stimulation of varying frequency for 1 hour per day for 12 consecutive weeks registered statistically significant improvement in outcome measures that assess arterial inflow and walking capacity in claudicants with diabetes mellitus. These results favor the use of electrostimulation as a therapeutic measure in this high-risk population.

Respiratory flow and vital signs associated with the intensity of functional electrical stimulation delivered to human abdominal muscles during quiet breathing

[Purpose] The purpose of this study was to examine the effects of increasing the intensity of functional electrical stimulation delivered to abdominal muscles during quiet breathing on respiratory flow, vital signs and pain in healthy subjects. [Subjects and Methods] Electrical stimulation was delivered bilaterally using one pair of high-conductivity gel-skin plate electrodes, placed on both sides of the abdomen, to nine healthy males. Subjects were required to breathe normally through a face mask for 2 minutes while in a supine position. The stimulation intensity was incrementally increased by 10 mA until reaching 100 mA. Respiratory parameters, vital signs and pain based on the visual analog scale were measured for each intensity of electrical stimulation. [Results] Transcutaneous oxygen saturation showed a slight upward trend in association with increasing stimulation intensity, but there were no significant changes in pulse or blood pressure. Respiratory flow, tidal volume, and minute ventilation increased significantly as the stimulation intensity rose. [Conclusion] This study revealed that functional electrical stimulation can be safely delivered to human abdominal muscles without causing vital sign abnormalities. It was also found that the appropriate intensity level of electrical stimulation for achieving effects on respiratory flow while also minimizing pain is 60–80 mA.

A Single Session of Neuromuscular Electrical Stimulation Enhances Vascular Endothelial Function and Peripheral Blood Circulation in Patients With Acute Myocardial Infarction

This study aimed to investigate whether a single session of neuromuscular electrical stimulation (NMES) can enhance vascular endothelial function and peripheral blood circulation in patients with acute myocardial infarction (AMI). Thirty-four male patients with AMI were alternately assigned to 2 groups, and received NMES with muscle contraction (NMES group, n = 17) or without muscle contraction (control group, n = 17) after admission. NMES was performed for quadriceps and gastrocnemius muscles of both legs for 30 minutes. We measured systolic blood pressure as a parameter of cardiovascular responses and the low-frequency component of blood pressure variability as an index of sympathetic activity. Reactive hyperemia peripheral arterial tonometry (RH-PAT) index and transcutaneous oxygen pressure in foot (Foot-tcPO₂) were also measured as parameters of vascular endothelial function and peripheral blood circulation, respectively. All patients completed the study without severe adverse events. Systolic blood pressure and the low-frequency component increased significantly during the NMES session in both groups (P < 0.01 and P < 0.05, respectively). However, elevation from systolic blood pressure at rest was < 10 mmHg in both groups. In the NMES group, the RH-PAT index and Foot-tcPO₂ increased significantly after NMES (P < 0.05 and P < 0.001, respectively). No significant changes were observed in these parameters throughout the session in the control group. In conclusion, a single session of NMES with muscle contraction enhanced vascular endothelial function, leading to improvement in peripheral blood circulation without inducing excessive cardiovascular and autonomic responses in patients with AMI (UMIN000014196).

Neuromuscular electrical stimulation for muscle weakness in adults with advanced disease

BACKGROUND

This review is an update of a previously published review in the Cochrane Database of Systematic Reviews Issue 1, 2013 on Neuromuscular electrical stimulation for muscle weakness in adults with advanced disease.Patients with advanced progressive disease often experience muscle weakness, which can impact adversely on their ability to be independent and their quality of life. In those patients who are unable or unwilling to undertake whole-body exercise, neuromuscular electrical stimulation (NMES) may be an alternative treatment to enhance lower limb muscle strength. Programmes of NMES appear to be acceptable to patients and have led to improvements in muscle function, exercise capacity, and quality of life. However, estimates regarding the effectiveness of NMES based on individual studies lack power and precision.

OBJECTIVES

Primary objective: to evaluate the effectiveness of NMES on quadriceps muscle strength in adults with advanced disease. Secondary objectives: to examine the safety and acceptability of NMES, and its effect on peripheral muscle function (strength or endurance), muscle mass, exercise capacity, breathlessness, and health-related quality of life.

SEARCH METHODS

We identified studies from searches of the Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Database of Systematic Reviews (CDSR), and Database of Abstracts of Reviews of Effects (DARE) (the Cochrane Library), MEDLINE (OVID), Embase (OVID), CINAHL (EBSCO), and PsycINFO (OVID) databases to January 2016; citation searches, conference proceedings, and previous systematic reviews.

SELECTION CRITERIA

We included randomised controlled trials in adults with advanced chronic respiratory disease, chronic heart failure, cancer, or HIV/AIDS comparing a programme of NMES as a sole or adjunct intervention to no treatment, placebo NMES, or an active control. We imposed no language restriction.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data on study design, participants, interventions, and outcomes. We assessed risk of bias using the Cochrane 'Risk of bias' tool. We calculated mean differences (MD) or standardised mean differences (SMD) between intervention and control groups for outcomes with sufficient data; for other outcomes we described findings from individual studies. We assessed the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

Eighteen studies (20 reports) involving a total of 933 participants with COPD, chronic respiratory disease, chronic heart failure, and/or thoracic cancer met the inclusion criteria for this update, an additional seven studies since the previous version of this review. All but one study that compared NMES to resistance training compared a programme of NMES to no treatment or placebo NMES. Most studies were conducted in a single centre and had a risk of bias arising from a lack of participant or assessor blinding and small study size. The quality of the evidence using GRADE comparing NMES to control was low for quadriceps muscle strength, moderate for occurrence of adverse events, and very low to low for all other secondary outcomes. We downgraded the quality of evidence ratings predominantly due to inconsistency among study findings and imprecision regarding estimates of effect. The included studies reported no serious adverse events and a low incidence of muscle soreness following NMES.NMES led to a statistically significant improvement in quadriceps muscle strength as compared to the control (12 studies; 781 participants; SMD 0.53, 95% confidence interval (CI) 0.19 to 0.87), equating to a difference of approximately 1.1 kg. An increase in muscle mass was also observed following NMES, though the observable effect appeared dependent on the assessment modality used (eight studies, 314 participants). Across tests of exercise performance, mean differences compared to control were statistically significant for the 6-minute walk test (seven studies; 317 participants; 35 m, 95% CI 14 to 56), but not for the incremental shuttle walk test (three studies; 434 participants; 9 m, 95% CI -35 to 52), endurance shuttle walk test (four studies; 452 participants; 64 m, 95% CI -18 to 146), or for cardiopulmonary exercise testing with cycle ergometry (six studies; 141 participants; 45 mL/minute, 95% CI -7 to 97). Limited data were available for other secondary outcomes, and we could not determine the most beneficial type of NMES programme.

AUTHORS' CONCLUSIONS

The overall conclusions have not changed from the last publication of this review, although we have included more data, new analyses, and an assessment of the quality of the evidence using the GRADE approach. NMES may be an effective treatment for muscle weakness in adults with advanced progressive disease, and could be considered as an exercise treatment for use within rehabilitation programmes. Further research is very likely to have an important impact on our confidence in the estimate of effect and may change the estimate. We recommend further research to understand the role of NMES as a component of, and in relation to, existing rehabilitation approaches. For example, studies may consider examining NMES as an adjuvant treatment to enhance the strengthening effect of programmes, or support patients with muscle weakness who have difficulty engaging with existing services.

Neuromuscular electrical stimulation of the thighs in cardiac patients with implantable cardioverter defibrillators

Background

The aim of this systematic review was to update scientific knowledge concerning the safety of neuromuscular electrical stimulation (NMES) to increase exercise capacity and prevent cardiac cachexia in patients with implantable cardioverter defibrillators (ICDs).

Methods

A systematic review including the electronic databases PubMed, MEDLINE, and SCOPUS was conducted for the time period from 1966 to March 31, 2016.

Results

Only four articles fulfilled the inclusion criteria (three original articles/safety studies and one case report). The three (safety) studies used NMES to increase muscle strength and/or endurance capacity of the thighs. NMES did not show electromagnetic interference (EMI) with ICD function. EMI was described in a case report of 2 patients with subpectoral ICDs and application of NMES on abdominal muscles.

Conclusion

This review indicates that NMES may be applied in cardiac ICD patients if 1) individual risks (e. g., pacing dependency, acute heart failure, unstable angina, ventricular arrhythmic episode in the last 3 months) are excluded by performing a safety check before starting NMES treatment and 2) “passive” exercise using NMES is performed only for thighs and gluteal muscles in 3) compliant ICD patients (especially for home-based NMES) and 4) the treatment is regularly supervised by a physician and the device is examined after the first use of NMES to exclude EMI. Nevertheless, further studies including larger sample sizes are necessary to exclude any risk when NMES is used in this patient group.

Muscle electrical stimulation improves neurovascular control and exercise tolerance in hospitalised advanced heart failure patients

BACKGROUND

We investigated the effects of muscle functional electrical stimulation on muscle sympathetic nerve activity and muscle blood flow, and, in addition, exercise tolerance in hospitalised patients for stabilisation of heart failure.

METHODS

Thirty patients hospitalised for treatment of decompensated heart failure, class IV New York Heart Association and ejection fraction ≤ 30% were consecutively randomly assigned into two groups: functional electrical stimulation (n = 15; 54 ± 2 years) and control (n = 15; 49 ± 2 years). Muscle sympathetic nerve activity was directly recorded via microneurography and blood flow by venous occlusion plethysmography. Heart rate and blood pressure were evaluated on a beat-to-beat basis (Finometer), exercise tolerance by 6-minute walk test, quadriceps muscle strength by a dynamometer and quality of life by Minnesota questionnaire. Functional electrical stimulation consisted of stimulating the lower limbs at 10 Hz frequency, 150 ms pulse width and 70 mA intensity for 60 minutes/day for 8-10 consecutive days. The control group underwent electrical stimulation at an intensity of < 20 mA.

RESULTS

Baseline characteristics were similar between groups, except age that was higher and C-reactive protein and forearm blood flow that were smaller in the functional electrical stimulation group. Functional electrical stimulation significantly decreased muscle sympathetic nerve activity and increased muscle blood flow and muscle strength. No changes were found in the control group. Walking distance and quality of life increased in both groups. However, these changes were greater in the functional electrical stimulation group.

CONCLUSION

Functional electrical stimulation improves muscle sympathetic nerve activity and vasoconstriction and increases exercise tolerance, muscle strength and quality of life in hospitalised heart failure patients. These findings suggest that functional electrical stimulation may be useful to hospitalised patients with decompensated chronic heart failure.

Light-emitting diode therapy (LEDT) improves functional capacity in rats with heart failure

The syndrome of heart failure (HF) promotes central and peripheral dysfunctions that result in functional capacity decrease, leading to fatigue, dyspnea, and exercise intolerance. The use of light-emitting diode therapy (LEDT) has shown good results reducing fatigue and exercise intolerance, when applied on skeletal muscles before or after exercises. Thereby, the aim of this study was to compare the effects of LEDT on functional capacity, aerobic power, and hemodynamic function in HF rats. Male Wistar rats (230-260 g) were randomly allocated into three experimental groups: Sham (n = 6), Control-HF (n = 4), and LEDT-HF (n = 6). The animals were subjected to an exercise performance test (ET) with gas analysis coupled in a metabolic chamber for rats performed two times (6 and 14 weeks after myocardial infarction). On the day after the baseline aerobic capacity test, the animals were submitted during 8 weeks to the phototherapy protocol, five times/week, 60 s of irradiation, 6 J delivered per muscle group. Statistical analysis was performed by one- and two-way ANOVAs with repeated measures and Student-Newman-Keuls post hoc tests (p ≤ 0.05). Comparing the percentage difference (Δ) between baseline and the final ET, there was no significant difference for the VO2max variable considering all groups. However, Sham and LEDT-HF groups showed higher relative values than the Control-HF group, respectively, for distance covered (27.7 and 32.5 %), time of exercise test (17.7 and 20.5 %), and speed (13.6 and 12.2 %). In conclusion, LEDT was able to increase the functional capacity evaluated by distance covered, time, and speed of exercise in rats with HF.

Electrical stimulation influences satellite cell differentiation after sciatic nerve crush injury in rats

INTRODUCTION

Electrical stimulation is often used to prevent muscle atrophy and preserve contractile function, but its effects on the satellite cell population after nerve injury are not well understood. In this study we aimed to determine whether satellite cell differentiation is affected by electrical stimulation after nerve crush.

METHODS

The sciatic nerves of Sprague-Dawley (SD) rats were crushed. Half of the injured rats received daily electrical stimulation of the gastrocnemius muscle, and the others did not. Tests for detecting paired box protein 7 (Pax7), myogenic differentiation antigen (MyoD), embryonic myosin heavy chain (eMyHC), and force production were performed 2, 4, and 6 weeks after injury.

RESULTS

More Pax7+/MyoD+ nuclei in stimulated muscles were observed than in non-stimulated muscles. eMyHC expression was elevated in stimulated muscles and correlated positively with enhanced force production.

CONCLUSIONS

Increased satellite cell differentiation is correlated with preserved muscle function in response to electrical stimulation after nerve injury.

The feasibility and acceptability of neuromuscular electrical stimulation to improve exercise performance in patients with advanced cancer: a pilot study

Background

To determine the feasibility and acceptability of lower limb neuromuscular electrical stimulation (NMES) as a home-based exercise therapy in patients with cancer who could not attend hospital-based exercise training.

Methods

A single-arm prospective pilot study of NMES, applied daily to both quadriceps muscles for six weeks. Participants were recruited from patients referred to a hospital-based multi-disciplinary supportive care team specializing in treatment of patients with nutritional depletion and functional decline.

Results

Of the 15 participants who underwent baseline testing, 10 (67%) completed the study and only one (7%) withdrew because of discomfort due to NMES treatment. 7/10 (70%) of participants used NMES at least three times a week for the duration of the study. Use of NMES did not lead to significant improvements in physical performance tests.

Conclusions

NMES is a feasible and acceptable intervention for home use in patients with cancer, poor performance status and metastatic disease. However, whether NMES is an effective strategy to stabilize or improve physical performance in such patients is not proven.

Electrical muscle stimulation in the intensive care setting: a systematic review

CONTEXT

The role of electrical muscle stimulation in intensive care has not previously been systematically reviewed.

OBJECTIVES

To identify, evaluate, and synthesize the evidence examining the effectiveness and the safety of electrical muscle stimulation in the intensive care, and the optimal intervention variables.

DATA SOURCES

A systematic review of articles using eight electronic databases (Cumulative Index to Nursing and Allied Health Literature, Cochrane Library, Excerpta Medica Database, Expanded Academic ASAP, MEDLINE, Physiotherapy Evidence Database, PubMed, and Scopus) personal files were searched, and cross-referencing was undertaken.

ELIGIBILITY CRITERIA

Quantitative studies published in English, assessing electrical muscle stimulation in intensive care, were included.

DATA EXTRACTION AND DATA SYNTHESIS

One reviewer extracted data using a standardized form, which were cross-checked by a second reviewer. Quality appraisal was undertaken by two independent reviewers using the Physiotherapy Evidence Database and Newcastle-Ottawa scales, and the National Health and Medical Research Council Hierarchy of Evidence Scale. Preferred Reporting Items for Systematic Reviews guidelines were followed.

RESULTS

Nine studies on six individual patient groups of 136 participants were included. Eight were randomized controlled trials, with four studies reporting on the same cohort of participants. Electrical muscle stimulation appears to preserve muscle mass and strength in long-stay participants and in those with less acuity. No such benefits were observed when commenced prior to 7 days or in patients with high acuity. One adverse event was reported. Optimal training variables and safety of the intervention require further investigation.

CONCLUSIONS

Electrical muscle stimulation is a promising intervention; however, there is conflicting evidence for its effectiveness when administered acutely. Outcomes measured are heterogeneous with small sample sizes.

Acute electromyostimulation decreases muscle sympathetic nerve activity in patients with advanced chronic heart failure (EMSICA Study)

Background

Muscle passive contraction of lower limb by neuromuscular electrostimulation (NMES) is frequently used in chronic heart failure (CHF) patients but no data are available concerning its action on sympathetic activity. However, Transcutaneous Electrical Nerve Stimulation (TENS) is able to improve baroreflex in CHF. The primary aim of the present study was to investigate the acute effect of TENS and NMES compared to Sham stimulation on sympathetic overactivity as assessed by Muscle Sympathetic Nerve Activity (MSNA).

Methods

We performed a serie of two parallel, randomized, double blinded and sham controlled protocols in twenty-two CHF patients in New York Heart Association (NYHA) Class III. Half of them performed stimulation by TENS, and the others tested NMES.

Results

Compare to Sham stimulation, both TENS and NMES are able to reduce MSNA (63.5 ± 3.5 vs 69.7 ± 3.1 bursts / min, p < 0.01 after TENS and 51.6 ± 3.3 vs 56.7 ± 3.3 bursts / min, p < 0, 01 after NMES). No variation of blood pressure, heart rate or respiratory parameters was observed after stimulation.

Conclusion

The results suggest that sensory stimulation of lower limbs by electrical device, either TENS or NMES, could inhibit sympathetic outflow directed to legs in CHF patients. These properties could benefits CHF patients and pave the way for a new non-pharmacological approach of CHF.

Noninvasive evaluation of electrical stimulation impacts on muscle hemodynamics via integrating diffuse optical spectroscopies with muscle stimulator

Technologies currently available for the monitoring of electrical stimulation (ES) in promoting blood circulation and tissue oxygenation are limited. This study integrated a muscle stimulator with a diffuse correlation spectroscopy (DCS) flow-oximeter to noninvasively quantify muscle blood flow and oxygenation responses during ES. Ten healthy subjects were tested using the integrated system. The muscle stimulator delivered biphasic electrical current to right leg quadriceps muscle, and a custom-made DCS flow-oximeter was used for simultaneous measurements of muscle blood flow and oxygenation in both legs. To minimize motion artifact of muscle fibers during ES, a novel gating algorithm was developed for data acquisition at the time when the muscle was relaxed. ES at 2, 10, and 50 Hz were applied for 20 min on each subject in three days sequentially. Results demonstrate that the 20-min ES at all frequencies promoted muscle blood flow significantly. However, only the ES at 10 Hz resulted in significant and persistent increases in oxy-hemoglobin concentration during and post ES. This pilot study supports the application of the integrated system to quantify tissue hemodynamic improvements for the optimization of ES treatment in patients suffering from diseases caused by poor blood circulation and low tissue oxygenation (e.g., pressure ulcer).

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.

Acute effects of muscular counterpulsation therapy on cardiac output and safety in patients with chronic heart failure

Our aim was to investigate acute effects of muscular counterpulsation (MCP) on hemodynamic parameters and to evaluate its safety in regard to myocardial integrity and interferences with implanted rhythm devices in patients with chronic heart failure (CHF). A total of 22 patients with CHF (16 male, 67.8 ± 9.5 years, New York Heart Association [NYHA] class II + III, left ventricular ejection fraction 29.6 ± 6.6%) were treated with MCP for 3 consecutive days for 45 min, while hemodynamic parameters were measured noninvasively by bioimpedance (Task Force Monitor). Laboratory control and a complete device testing were performed prior to the first and after the third treatment. In addition, continuous rhythm device interrogation was performed online during the first MCP application. During each application, a significant increase in cardiac output (CO; average change +2.08 ± 2.33 L/min, P < 0.05) was documented. This increase was due to a decrease of total peripheral resistance (-336 ± 530 dyn × s/cm(5) , P < 0.05), to an augmented stroke volume (+8.35 ±  20.86 mL, P = n.s.), and an increase in heart rate (+17.12 ± 21.12 bpm, P < 0.05). Cardiac markers and enzymes were within normal limits at all times and did not increase during treatment. MCP stimuli were monitored using surface electrocardiogram, and no abnormal sensing or pacing events occurred. MCP acutely improves CO in patients with stable CHF. No adverse influence on myocardial integrity was observed nor were any inappropriate sensing or pacing artifacts detected in patients with implanted rhythm devices.

Regeneration of skeletal muscle

Skeletal muscle has a robust capacity for regeneration following injury. However, few if any effective therapeutic options for volumetric muscle loss are available. Autologous muscle grafts or muscle transposition represent possible salvage procedures for the restoration of mass and function but these approaches have limited success and are plagued by associated donor site morbidity. Cell-based therapies are in their infancy and, to date, have largely focused on hereditary disorders such as Duchenne muscular dystrophy. An unequivocal need exists for regenerative medicine strategies that can enhance or induce de novo formation of functional skeletal muscle as a treatment for congenital absence or traumatic loss of tissue. In this review, the three stages of skeletal muscle regeneration and the potential pitfalls in the development of regenerative medicine strategies for the restoration of functional skeletal muscle in situ are discussed.

Effect of transcutaneous electrical muscle stimulation on muscle volume in patients with septic shock

OBJECTIVE

Intensive care unit admission is associated with muscle wasting and impaired physical function. We investigated the effect of early transcutaneous electrical muscle stimulation on quadriceps muscle volume in patients with septic shock.

DESIGN

Randomized interventional study using a single-legged exercise design with the contralateral leg serving as a paired control.

SETTING

A mixed 18-bed intensive care unit at a tertiary care university hospital.

PATIENTS

Eight adult male intensive care unit patients with septic shock included within 72 hrs of diagnosis.

INTERVENTIONS

After randomization of the quadriceps muscles, transcutaneous electrical muscle stimulation was applied on the intervention side for 7 consecutive days and for 60 mins per day. All patients underwent computed tomographic scans of both thighs immediately before and after the 7-day treatment period. The quadriceps muscle was manually delineated on the computed tomography slices, and muscle volumes were calculated after three-dimensional reconstruction.

MEASUREMENTS AND MAIN RESULTS

Median age and Acute Physiology and Chronic Health Evaluation II score were 67 years (interquartile range, 64-72 years) and 25 (interquartile range, 20-29), respectively. During the 7-day study period, the volume of the quadriceps muscle on the control thigh decreased by 16% (4-21%, p=.03) corresponding to a rate of 2.3% per day. The volume of the stimulated muscle decreased by 20% (3-25%, p=.04) corresponding to a rate of 2.9% per day (p=.12 for the difference in decrease). There was no difference in muscle volume between the stimulated and nonstimulated thigh at baseline (p=.10) or at day 7 (p=.12). The charge delivered to the muscle tissue per training session (0.82 [0.66-1.18] coulomb) correlated with the maximum sequential organ failure assessment score.

CONCLUSIONS

We observed a marked decrease in quadriceps volume within the first week of intensive care for septic shock. This loss of muscle mass was unaffected by transcutaneous electrical muscle stimulation applied for 60 mins per day for 7 days.

Neuromuscular electrical stimulation improves GLUT-4 and morphological characteristics of skeletal muscle in rats with heart failure

AIM

Changes in skeletal muscle morphology and metabolism are associated with limited functional capacity in heart failure, which can be attenuated by neuromuscular electrical stimulation (ES). The purpose of the present study was to analyse the effects of ES upon GLUT-4 protein content, fibre structure and vessel density of the skeletal muscle in a rat model of HF subsequent to myocardial infarction.

METHODS

Forty-four male Wistar rats were assigned to one of four groups: sham (S), sham submitted to ES (S+ES), heart failure (HF) and heart failure submitted to ES (HF+ES). The rats in the ES groups were submitted to ES of the left leg during 20 days (2.5 kHz, once a day, 30 min, duty cycle 50%- 15 s contraction/15 s rest). After this period, the left tibialis anterior muscle was collected from all the rats for analysis.

RESULTS

HF+ES rats showed lower values of lung congestion when compared with HF rats (P = 0.0001). Although muscle weight was lower in HF rats than in the S group, thus indicating hypotrophy, 20 days of ES led to their recovery (P < 0.0001). In both groups submitted to ES, there was an increase in muscle vessel density (P < 0.04). Additionally, heart failure determined a 49% reduction in GLUT-4 protein content (P < 0.03), which was recovered by ES (P < 0.01).

CONCLUSION

In heart failure, ES improves morphological changes and raises GLUT-4 content in skeletal muscle.