Biventricular pacing is not a cure for heart failure. It is a supplement, rather than a replacement for, drug therapy. However, major studies have shown benefit with the biventricular pacemaker in several areas. These include:

• Improved exercise capacity
  
  
• Improved quality of life (e.g., relief of symptoms such as shortness of breath)
  
  
• Improved ejection fraction of the left ventricle
  
  
• Improved New York Heart Association classification
  
  
• Reduced hospitalizations
  
  
• With the combined biventricular pacemaker/ICD, a reduction in the incidence of sudden cardiac death.
  
  
• A delay in heart transplantation

Biventricular pacing may also have an impact on remodeling the heart, a harmful physical change in the heart that occurs with heart failure. Remodeling is characterized by enlargement and thinning of the heart’s left ventricle. There is an increased use of oxygen, greater degree of mitral valve regurgitation, and decreased ejection fraction. Remodeling sets off a “domino effect” of further damage to heart cells and more severe heart disease. Studies suggest that biventricular pacing can reverse the process. This beneficial effect on the heart is called “reverse remodeling.”