Patients afflicted with Chronic Heart Failure (HF) typically do not maintain stable cardiac function for the remainder of their life and consequently require continuous medical management and intermittent hospital admissions. Several investigations have demonstrated that electrical muscle stimulation (EMS) produces positive physiologic and psychological adaptations in patients with HF. However not all the EMS modalities were been evaluated on this population or not even were tested based on present recognized gold standard clinical parameters after a short period of treatment. The primary aims of the proposed study is to: Determine the effect of a five week home based of three EMS modalities on prognostics markers, perceived quality of life, muscle force and electrical activity in subjects diagnosed with HF.

Introduction: Chronic Heart Failure (HF) patients are a significant health care burden in many countries. Patients afflicted with HF typically do not maintain stable cardiac function for the remainder of their life and consequently require continuous medical management and intermittent hospital admissions. Several investigations have demonstrated that electrical muscle stimulation (EMS) produces positive physiologic and psychological adaptations in patients with HF. However not all the EMS modalities were been evaluated on this population or not even were tested based on present recognized gold standard clinical parameters after a short period of treatment. The impact of use of low frequency (FES) and medium-frequency currents (MAC and BMAC) as EMS on the VE/VCO2 and BNP has likewise not been investigated in patients with HF.

Purposes: The primary aims of the proposed study is to: Determine the effect of a five week home based EMS modalities (a) Functional electrical stimulation (FES), (b) medium-frequency alternating current (MAC) and (c) burst-modulated medium-frequency alternating current (BMAC) training program on the VE/VCO2 slope, Brain Natriuretic Peptide (BNP) level, peak VO2, VO2 at Ventilatory Threshold (VT), perceived quality of life, muscle force and electrical activity in subjects diagnosed with HF (NYHA III and IV). Examine changes in the previously outlined outcome measurements five weeks after cessation of the EMS ((a) FES, (b) MAC and (c) BMAC) training program.

Procedures: We will recruit 40 persons (10 for each EMS modalities and 10 control subjects) diagnosed with HF. A group of control subjects will participate using a sham current. The protocol can be conceptually divided into four sections in the following chronological sequence: (1) baseline assessment (body composition by a bone densitometer X-ray Dual energy X-Ray absortometry - DXA, Resting blood pressure and heart rate, complete blood count and BNP analysis); Living with Heart Failure Questionnaire (MLWHFQ); A physician-supervised maximal aerobic exercise test using a metabolic cart (Vmax, Viasys, USA) (VO2, VE/VCO2, VT); isokinetic peak torque (Biodex System III, Isokinetic Dynamometer, Biodex Medical, Inc., Shirley, NY) and electrical activity (Miotec, Brazil), (2) five week EMS training program (bilateral quadriceps and gastrocnemius for 5 days a week for 1 hour to each muscle group with FES, MAC and BMAC training program), (3) immediate post-training assessment within 5 days of completion of the EMS training program and a (4) final analysis five weeks after cessation of the EMS training program.

Inclusion Criteria:

• (1) Male or female ≥ 21 and ≤ 80 years of age.
• (2) Current HF symptoms consistent with NYHA class III-IV.
• (3) On stable HF pharmacological therapy for at least one month prior to data collection.
• (4) Left ventricular ejection fraction < 45% documented within 3 months of enrollment (obtained from subjects medical records).
• (5) No planned elective surgery or pacemaker implantation at the time of study initiation.
• (6) Hgb > 8.0 within 1 month of enrollment (obtained from subjects medical records).
• (7) Willingness to provide written informed consent.

Exclusion Criteria:

• (1) Inability to provide written informed consent.
• (2) Inability to walk on a treadmill.
• (3) Hemodynamically significant valvular heart disease.
• (4) Unstable angina.
• (5) Acute myocardial infarction within the previous 3 months.
• (6) Obstructive hypertrophic cardiomyopathy.
• (7) HF known to be secondary to pericardial disease or uncorrected valvular disease.
• (8) Chronic oxygen therapy.
• (9) Participation in another clinical trial within the past 30 days.
• (10) Participation in a regular exercise within the previous 6 months.
• (11) Previous implantation of a cardiac pacemaker or defibrillator.
• (12) Pregnancy.
• (13) Resting systolic blood pressure > 200 mmHg.
• (14) Failure to demonstrate the ability to operate the EMS unit.
• (15) Failure to be compliant with at least 75% of the EMS training sessions.