Ennis Stuart, McGregor Gordon, Hamborg Thomas, Jones Helen, Shave Robert, Singh Sally J, Banerjee Prithwish
Department of Cardiac Rehabilitation, University Hospitals Coventry & Warwickshire NHS Trust, Coventry, UK.
School of Sport, Cardiff Metropolitan University, Cardiff, UK.
BMJ Open. 2017 Aug 11;7(8):e016148. doi: 10.1136/bmjopen-2017-016148.
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.
Double blind (participants, outcome assessors), randomised study in a secondary care outpatient cardiac rehabilitation programme.
Patients with severe heart failure (New York Heart Association class III-IV) having left ventricular ejection fraction <40% documented by echocardiography were eligible.
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).
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.
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.
ISRCTN16749049.
对于难以坚持传统运动的慢性心力衰竭患者，低频电肌肉刺激（LF - EMS）可能有减轻呼吸困难和提高运动能力的潜力。本研究的目的是确定LF - EMS的随机对照试验是否可行。
在二级护理门诊心脏康复项目中进行的双盲（参与者、结果评估者）随机研究。
经超声心动图记录左心室射血分数<40%的重度心力衰竭（纽约心脏协会III - IV级）患者符合条件。
参与者（通过计算机远程）随机分为接受8周（每周5次，每次60分钟）的LF - EMS干预（4赫兹，持续，n = 30）或股四头肌和腘绳肌的假安慰剂（仅皮肤水平刺激，n = 30）。参与者在家中使用LF - EMS绑带，每周接受监督。
在试验期间测量干预的招募情况、依从性和耐受性以及生理结果（主要结果：6分钟步行试验，次要结果：股四头肌力量、生活质量和身体活动）。
171名符合条件的参与者中有60名（35.08%）被招募到试验中。60名患者中有12名（20%）（4名LF - EMS组和8名假安慰剂组）退出。41名患者（68.3%）至少70%的疗程遵守了方案。生理测量表明，两组在6分钟步行距离（p = 0.13）和生活质量（p = 0.55）方面无显著差异，尽管LF - EMS组这两个结果的改善更大。
重度心力衰竭患者可以被招募到LF - EMS研究中并耐受该研究。在晚期心力衰竭人群中进行更大规模的随机对照试验（RCT）在技术上是可行的，尽管坚持随访将具有挑战性。运动能力和生活质量的初步改善很小，如果计划进行更大规模的试验，应考虑这一点。
ISRCTN16749049。
