Resynchronization/Defibrillation for Ambulatory Heart Failure Trial in Patients With Permanent Atrial Fibrillation

Brief Summary

Atrial fibrillation (AF) and heart failure (HF) are two common heart conditions that are encountered with an increase in death and suffering. When both these two conditions occur in a patient, the patient's prognosis is poor with a reduced quality of life and impaired heart function. These patients have enlarged hearts, specifically the left ventricle (major pumping chamber), which impairs the heart's pumping capacity, leading to symptoms such as fatigue, shortness of breath from any type of exertion, and swelling, usually of the feet and ankles. In these HF patients who are in AF all of the time, who would otherwise be a suitable candidate for an implantable defibrillator to prevent sudden cardiac death, we would like to determine whether adding pacing of both ventricles will reduce heart size (left ventricular end systolic volume index LVESVi) as measured by ultrasound, which can improve its function and help the heart pump more efficiently. Other studies have shown that adding pacing to both ventricles is of benefit in HF patients with mild to moderate symptoms and have a regular heart rhythm. The Investigators now want to explore if this therapy will benefit those patients with a permanent irregular heart rhythm (AF).