HADH and congestive heart failure: Levels of CS increased following LF-NMES (15 Hertz) compared to sham-stimulation in patients with severe CHF [47] and did not change following HF-NMES (50 Hertz) in patients with severe COPD [54].Levels of HADH did not change following HF-NMES (50 Hertz) in patients with severe COPD [54].