Left bundle branch pacing better preserves ventricular mechanical synchrony than right ventricular pacing: a
Yankai Mao1,2, Jürgen Duchenne2, Yuan Yang1
1Department of Diagnostic Ultrasound and Echocardiography, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.
European Heart Journal. Cardiovascular Imaging
|November 7, 2023
Summary
Left bundle branch pacing (LBBP) better preserves left ventricular (LV) mechanical synchrony and function compared to right ventricular pacing (RVP). LBBP results in less LV mechanical dyssynchrony, maintaining better LV function over time.
Area of Science:
- Cardiology
- Electrophysiology
- Cardiac Mechanics
Background:
- Left bundle branch pacing (LBBP) is known to improve electrical synchrony over right ventricular pacing (RVP).
- The impact of LBBP on left ventricular (LV) mechanical synchrony and function remains less understood compared to RVP.
Purpose of the Study:
- To investigate whether LBBP preserves LV mechanical synchronicity and function more effectively than RVP.
- To compare the effects of LBBP and RVP on mechanical dyssynchrony and LV performance.
Main Methods:
- Sixty patients requiring pacing for bradycardia were enrolled, randomized to LBBP (n=31) or RVP (n=29).
- Echocardiography assessed mechanical synchrony (lateral wall-septal wall work difference) and LV function (ejection fraction, global longitudinal strain) at baseline, post-implantation, and 1-year follow-up.
- Analysis included septal flash, apical rocking, and strain patterns.
Main Results:
- At 1-year follow-up, LBBP showed a significantly smaller lateral wall-septal wall work difference (439 mmHg·% vs. 1253 mmHg·%, P<0.01) compared to RVP.
- RVP was associated with increased septal flash, apical rocking, and advanced strain patterns.
- LV ejection fraction and global longitudinal strain decreased more with RVP (ΔLVEF: -7.4%, ΔLVGLS: -4.8%) than with LBBP (ΔLVEF: 0.3%, ΔLVGLS: -1.4%) at 1 year (P<0.01).
- Increased mechanical dyssynchrony independently correlated with adverse LV remodeling and dysfunction.
Conclusions:
- LBBP induces less left ventricular mechanical dyssynchrony compared to RVP.
- LBBP preserves left ventricular function better than RVP, likely due to more physiologic electrical conduction.
- LBBP represents a potentially superior pacing strategy for maintaining cardiac mechanics and function.
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