Low Frequency Neuromuscular Stimulation Effect on Ergoreflex Activity in Advanced Heart Failure

Background: Heart failure is a syndrome characterized by cardiac dysfunction with either left ventricular dilation or hypertrophy causing cardinal manifestations of dyspnea, fatigue and exercise intolerance.

Objectives: To determine the effect of low frequency neuromuscular stimulation on ergoreflex activity in advanced heart failure. Methods: Thirty patients of with advanced heart failure were included in this study with mean age of 60 years. They received eight weeks (four times a week) of increasing amplitude low frequency neuromuscular stimulation on Quadriceps and calf muscles after thorough assessment of ergoreflex, ejection fraction and assessment of disability via Minnesota Living with Heart Failure Questionnaire.

Results: Statistical significant alteration of ergo reflex contribution associated with decreased disability without any statistically significant changes in ejection fraction. The percentages of changes in minute ventilation (VE) and carbon dioxide production (VCO2 ) and maximum oxygen consumption (VO2 ) were 37.83%, -36.38% and 25.46% respectively. These changes were associated with improved functional, emotional and psychological status of the patients with a decline of Minnesota Living with Heart Failure Questionnaire score by -29.87%.

Conclusion: Low frequency neuromuscular stimulation altered ergoreflex contribution leading to higher functional levels.