Effect of cardiac resynchronization therapy on ventricular repolarization: a meta-analysis
1Department of Cardiology, The First People's Hospital of Hangzhou; Hangzhou-China. duanxu410@yahoo.com.cn.
Anatolian Journal of Cardiology
|October 22, 2014
Summary
Cardiac resynchronization therapy (CRT) does not worsen ventricular repolarization with biventricular pacing. However, left ventricular pacing may prolong the Tp-e interval, indicating a potential proarrhythmic effect.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Devices
Background:
- Cardiac resynchronization therapy (CRT) is used to treat heart failure.
- Previous studies on CRT's effect on ventricular repolarization yielded inconsistent results.
- Concerns exist regarding a potential proarrhythmic effect of CRT.
Purpose of the Study:
- To determine the effect of CRT on ventricular repolarization.
- To clarify the impact of biventricular (BV) and left ventricular (LV) pacing on repolarization parameters.
Main Methods:
- A meta-analysis of 14 studies was performed.
- Investigated the effect of CRT on QT interval (QT), JT interval (JT), QT dispersion (QTD), and Tp-e interval.
- Compared pacing modes (BV, LV) with intrinsic ventricular rhythm.
Main Results:
- Biventricular pacing showed no significant difference in QT, JT, or Tp-e compared to intrinsic rhythm.
- QT dispersion (QTD) was lower with BV pacing, though significance was ambiguous (p=0.05).
- Left ventricular pacing significantly prolonged the Tp-e interval (p=0.03) compared to intrinsic rhythm.
Conclusions:
- Biventricular pacing in CRT does not appear to have a proarrhythmic effect on ventricular repolarization.
- Left ventricular pacing may prolong the Tp-e interval, suggesting a potential proarrhythmic risk.
- Further research is needed to fully understand the repolarization effects of different CRT pacing strategies.
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