Abstract 12345: QRS Duration and Radial Dyssynchrony Are Associated with Survival in Patients with Ischemic Cardiomyopathy Undergoing Cardiac Resynchronization Therapy
Introduction: Patients with ischemic cardiomyopathy appear to have a less favorable outcome following cardiac resynchronization therapy (CRT) than those with nonischemic heart failure. However, electrocardiographic and echocardiographic features associated with their outcome are unclear. We tested the hypothesis that QRS duration and echocardiographic dyssynchrony are associated with long-term outcome in patients with ischemic cardiomyopathy after CRT.
Methods: We prospectively studied 118 patients with ischemic cardiomyopathy for CRT, with disease defined by coronary angiography. All were NYHA class III-IV, had QRS ≥120ms, and ejection fraction ≤35%. Baseline dyssynchrony was assessed by speckle tracking radial strain with positive pre-defined as anteroseptal-to-posterior wall delay ≥130ms. Patients were grouped by baseline QRS width being narrower, 120–140ms, or wider > 140ms and positive or negative radial dyssynchrony. Long-term outcomes were pre-specified as: death, transplant or left ventricular assist device (LVAD) and tracked over 4 years.
Results: Baseline characteristics including: age, EF, and NYHA Class were similar in each group. Male gender was more common in those with wider QRS (87% vs 69%, p=0.04). Those with QRS >140ms had a significantly more favorable long-term survival (p=0.0045) than those with narrower QRS. Radial dyssynchrony when combined with QRS width was even more closely associated with outcome. Patients with QRS 120–140ms who lacked radial dyssynchrony had the least favorable outcome after CRT (p=0.0007).
Conclusion: In patients with heart failure of ischemic etiology, QRS width and radial dyssynchrony combine to predict important long term outcome events after CRT.
- © 2010 by American Heart Association, Inc.