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Updated: May 19, 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
Relationship between fragmented QRS and response to cardiac resynchronization therapy
Umut Celikyurt1, Aysen Agacdiken, Tayfun Sahin
1Department of Cardiology, Kocaeli University, Umuttepe Yerleskesi, 41380, Kocaeli, Turkey. ycelikyurt@gmail.com
Summary
Fragmented wide QRS (f-wQRS) on ECG may identify heart failure patients unlikely to respond to cardiac resynchronization therapy (CRT). Lack of f-wQRS predicts a positive response, suggesting its utility in patient selection for CRT.
Area of Science:
- Cardiology
- Electrophysiology
- Heart Failure Management
Background:
- Cardiac resynchronization therapy (CRT) is a key treatment for heart failure (HF) patients with wide QRS complex.
- Fragmented QRS (fQRS) on electrocardiography (ECG) is linked to adverse cardiac events.
- The prognostic value of fragmented wide QRS (f-wQRS) in CRT candidates requires further investigation.
Purpose of the Study:
- To examine the association between f-wQRS and left ventricular (LV) dyssynchrony.
- To determine if f-wQRS predicts response to CRT in heart failure patients.
Main Methods:
- Fifty-three heart failure patients undergoing CRT were assessed for fQRS using standardized criteria.
- Left ventricular dyssynchrony was evaluated using interventricular mechanical delay (IVMD) and tissue Doppler imaging.
- CRT response was defined as a ≥15% reduction in LV end-systolic volume at 6-month follow-up.
Main Results:
- Fragmented wide QRS (f-wQRS) was identified in 32% of patients.
- Dyssynchrony was prevalent in both f-wQRS and non-f-wQRS groups.
- Lack of f-wQRS was the sole significant predictor of positive CRT response (OR 1.556, p=0.028).
Conclusions:
- While dyssynchrony is essential for CRT, it's not sufficient for patient selection.
- The presence of f-wQRS on baseline ECG may help identify heart failure patients unlikely to benefit from CRT.
- f-wQRS could be a valuable tool for optimizing CRT candidate selection.
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