Cardiac resynchronization therapy (CRT) is a proven treatment for selected patients with heart failure-induced conduction disturbances and dyssynchrony of the lower chambers of the heart. It comes in two forms- as a pacemaker system –CRT-P or in an ICD form- CRT-D. When used in combination with stable, optimal medical therapy, CRT is designed to reduce symptoms and improve cardiac function by restoring the mechanical sequence of ventricular activation and contraction. In involves addition of a third lead that wraps around the left lower chamber (left ventricle). A number of randomized, controlled clinical studies have demonstrated that CRT has a number of positive clinical effects, including:
- Improvement in cardiac function and structure
- Improvement in quality of life and functional capacity
- Improvement in exercise capacity
- Reduction in heart failure hospitalization
- Reduction in mortality (CRT-D) from progressive heart failure
About 2 out of 3 patients that receive this therapy see a significant improvement in the above symptoms.