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Progressive Paced QRS Widening: An Electrocardiographic Marker for Predicting Cardiac Resynchronization Therapy
Takayuki Shimizu1, Keijiro Nakamura1, Naohiko Nemoto2
1Division of Cardiovascular Medicine, Toho University, Ohashi Medical Center, Meguro-Ku, Japan.
Pacing and Clinical Electrophysiology : PACE
|September 17, 2025
Summary
Progressive widening of paced QRS duration (pQRSd) predicts the need for cardiac resynchronization therapy (CRT) upgrade in patients with right ventricular pacing. Monitoring pQRSd trends aids early identification of patients who may benefit from CRT.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Device Technology
Background:
- Chronic right ventricular (RV) pacing can lead to left ventricular dysfunction.
- This dysfunction may necessitate cardiac resynchronization therapy (CRT) upgrade.
Purpose of the Study:
- To evaluate if paced QRS duration (pQRSd) and its progression predict the need for CRT upgrade.
- To identify patients at high risk for CRT upgrade through pQRSd monitoring.
Main Methods:
- Retrospective analysis of 410 RV pacing-dependent patients (2017-2022).
- Analysis of pQRSd post-pacemaker implantation and before potential CRT upgrade.
- Calculation of ΔpQRSd (change in pQRSd).
Main Results:
- 51 patients (12.4%) underwent CRT upgrade.
- CRT upgrade associated with age, pQRSd before upgrade, and baseline LVEF.
- ΔpQRSd was significantly larger in CRT upgrade patients (16 ms vs. 0.6 ms).
- Optimal cut-off values identified for pQRSd and ΔpQRSd using ROC analysis.
Conclusions:
- Progressive widening of pQRSd is a novel marker for identifying patients needing CRT upgrade.
- Routine ECG monitoring of pQRSd trends enables early identification of CRT candidates.
- This strategy can help prevent advanced heart failure in RV-paced patients.
Keywords:
cardiac resynchronization therapychronic right ventricular pacingelectrocardiographic markerpaced QRS durationpacing‐induced cardiomyopathyupgradeMore Related Videos
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