Cardiac Resynchronization Therapy for Severe Drug Refractory Systolic Heart Failure

A substantial number of patients with severe congestive heart failure due to systolic dysfunction develop mechanical dyssynchrony of the left ventricle, which results in suboptimal filling, and contraction of this chamber and consequently reduced ejection of blood into the aorta. Furthermore the altered hemodynamics are accompanied with reduction of left ventricle ejection fraction, increased volumes of the heart, and increased morbidity and mortlity. Cardiac reysnchronization therapy using a biventricular pacemaker with three leads-the first placed in the right atrium, the second placed in the right ventricular apex and the third pacing lead positioned in a branch of the coronary sinus effectively aids the heart to pump in a synchronous fashion. Large scale randomized trials have demonstrated significant reduction in mortality and hospitalizations with this therapy in patients with severe heart failure refractory to optimal drug therapy. The reduction in mortality is preceded by significant improvement in clinical symptoms; quality of life and reverse left ventricle remodeling.