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Updated: May 22, 2026
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Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
QRS prolongation induced by cardiac resynchronization therapy correlates with deterioration in left ventricular
John Rickard1, Gregory Jackson, David D Spragg
1Heart and Vascular Institute, Cleveland Clinic, 9500 Euclid Blvd,Cleveland, OH 44122, USA. rickarj2@ccf.org
Heart Rhythm
|May 16, 2012
Summary
Cardiac resynchronization therapy (CRT) can worsen left ventricular (LV) function in some patients. QRS widening after CRT is linked to this deterioration, indicating a need for careful patient selection and monitoring.
Area of Science:
- Cardiology
- Electrophysiology
- Heart Failure Management
Background:
- Cardiac resynchronization therapy (CRT) improves left ventricular (LV) function in systolic dysfunction.
- However, a significant portion of patients do not respond or experience worsening LV function.
- Characteristics of these non-responders remain understudied.
Purpose of the Study:
- To identify patient characteristics associated with LV function deterioration after CRT.
- To investigate factors contributing to adverse outcomes in CRT recipients.
Main Methods:
- Clinical, electrocardiographic, and echocardiographic data were analyzed for 507 patients meeting CRT inclusion criteria.
- LV function deterioration was defined as a ≥5% absolute decrease in ejection fraction post-CRT.
- Multivariate models identified variables associated with LV deterioration.
Main Results:
- 11.8% of patients (60/507) experienced LV function deterioration.
- Deterioration was more common in men, those with non-left bundle branch block morphology, and a history of atrial fibrillation.
- Significant QRS widening post-CRT was strongly associated with LV deterioration (OR 1.14; P = .001).
Conclusions:
- QRS widening following CRT is a significant predictor of left ventricular function deterioration.
- These findings highlight the importance of monitoring QRS duration changes post-CRT.
- Further research may refine patient selection to mitigate risks of CRT-induced LV dysfunction.
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