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Updated: Jun 27, 2026

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
Is the optimal atrioventricular delay paced from right ventricular outflow tract different from that from right
Abstract:
The objective of this study was to compare the optimal atrioventricular delay (OAVD) paced from right ventricular outflow tract (RVOT) with that paced from right ventricular apex (RVA) in patients implanted with DDD pacemaker. A total of 43 patients implanted with DDD pacemaker due to high or third degree atrioventricular block were enrolled. The atrial lead was positioned in the right atrial appendage and the ventricular lead was randomly placed in RVOT (n=21) or RVA (n=22). AVD optimization increased aortic flow velocity integral both in RVOT and RVA paced patients. P wave duration (P<0.05) rather than QRS duration (P>0.10) was the independent determinant of OAVD. OAVD was similar between RVA and RVOT paced patients (116.81+/-34.00 ms vs 107.14+/-26.30 ms, P>0.05).
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