Cardiac resynchronization therapy for treatment of heart failure.

Abstract

Conduction abnormalities, commonly seen in systolic heart failure, lead to delayed activation of the myocardium as the electrical impulse spreads slowly without the aid of healthy conduction tissue. The resulting dyssynchronous ventricular contraction is mechanically less efficient, reducing systolic function and impairing diastolic filling. Simultaneous pacing of the right and left ventricles (i.e., biventricular pacing) reduces ventricular dyssynchronous contraction, overcoming these consequences of conduction delay. An important role for implantable rhythm-management devices providing cardiac resynchronization therapy has emerged in the optimization of ventricular function in heart failure. Long-term benefits in patient outcomes have been well established. With increasing use, understanding of cardiac resynchronization therapy devices and the principles behind the therapy are important for physicians providing perioperative and intensive care for patients with heart failure.