Title: Effects of continuous Electrical Muscle Stimulation on exercise capacity, physical activity and quality of life in advanced heart failure patients: a pilot study
Funder: Department of Health (England)

Abstract: The Research Questions: 1. What is the acceptability/tolerance and adherence to an 8 week LF-EMS intervention for advanced CHF patients? The main purpose of any pilot is to test whether different components of the study could work together in a large RCT if the pilot is successful: (a) Recruitment - consent rate and willingness to be randomised to LF-EMS intervention in advanced CHF patients will be measured. (b) Adherence to the intervention will be recorded by the LF-EMS technology itself and by the use of patient diaries. (c) Tolerance - subjects will be interviewed post intervention to gain detailed feedback about the ease of use of the LF-EMS straps in this patient group and how well they were able to tolerate this new therapy. An in-house questionnaire will also be used. 2. How convincing is ‘Sham’EMS as a placebo? This is integral for the blinding of subjects to the LF-EMS intervention for any prospective RCT. Patients will be interviewed after the 8 week intervention period and asked to guess which group they were in. 3. What is the variability in the measurement of the primary outcome 6MWT? This pilot will provide initial data for a sample size calculation for any future RCT. 4 Does LF-EMS of the leg muscles in debilitated (NYHA III/IV, LVEF This pilot will provide a preliminary indication of the effect of this intervention. A later full RCT will then aim to conclusively answer this question. The primary outcome will be the Six Minute Walk Test (6MWT). It is a well validated measure, practical, and applicable to the wider population of heart failure patients, particularly the elderly (NICE guidelines, 2010). Secondary outcome measures will be leg muscle strength (hand held leg dynamometry) and quality of life (measured by the disease specific Minnesota Living with Heart Failure Questionnaire). Measurements will be made at baseline, after the 8 week intervention period, and at 3 months follow-up. Physical activity levels will be measured by the Bodymedia© SenseWear Pro3 Armband. This device allows continuous recording of physiological signals from the body such as skin temperature, dissipated heat from the body (heat flux), galvanic skin response and movement. Algorithms are used to accurately determine total energy expenditure (TEE). Periods of physical activity are identified and quantified (movement, sleep and wake periods), while measuring the number of steps, resting metabolic rate and hence metabolic equivalents (METS) levels, in "free living" conditions give a comprehensive picture of the user’s activity level. Subjects will wear the armband for one week before and after the 8 week LF-EMS intervention, and for a week 3 months post intervention. Of all these measurements emphasis will be given to TEE and number of steps. 5. Are any potential improvements after using LF-EMS sustained over 3 months follow-up? Are patients able to participate in exercise programmes post intervention? Due to the complex multifaceted nature of advanced heart failure, there are competing physiological, socioeconomic and psychological factors that would determine when previously debilitated subjects could and would become more physically active. The number and percentage of subjects who are more active will be measured after 3 months post intervention follow-up. The LF-EMS straps have potential to aid many other cardiac patients unable to exercise because of orthopaedic, osteoarthritic or peripheral vascular disease limitations.


Research activity codes: 6.7 PHYSICAL
Health categories: CARDIOVASCULAR