Related Experiment Video
Updated: Jun 26, 2026
12:45
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
Unmasking Type 1 Brugada Pattern During Ajmaline Challenge Despite Left Bundle Branch Pacing
Paolo Pastori1, Cristina Balla2, Francesco Vitali2
1Cardiology Unit, Fidenza Hospital, Azienda USL of Parma, Fidenza, Italy.
JACC. Case Reports
|June 25, 2026
Summary
This study shows Brugada pattern is detectable even with left bundle branch pacing. Conduction system pacing does not obscure these crucial repolarization abnormalities.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Devices
Background:
- Brugada pattern is an electrocardiographic finding associated with increased risk of sudden cardiac death.
- Left bundle branch pacing (LBBP) is an alternative pacing method for heart block.
- Altered ventricular activation during pacing can affect electrocardiogram interpretation.
Purpose of the Study:
- To investigate the detectability of Brugada pattern during LBBP.
- To assess the impact of conduction system pacing on Brugada repolarization abnormalities.
Main Methods:
- A patient with syncope, right bundle branch block, and infra-Hisian atrioventricular block underwent LBBP.
- An ajmaline challenge was performed post-device implantation with high-precordial lead positioning.
- Electrocardiograms were analyzed during intrinsic rhythm and LBBP.
Main Results:
- A diagnostic type 1 Brugada pattern was unmasked by ajmaline challenge.
- The Brugada pattern was evident during both intrinsic beats and LBBP-paced beats.
- High-precordial lead positioning facilitated Brugada pattern recognition.
Conclusions:
- Diagnostic Brugada repolarization abnormalities can be recognized despite altered ventricular activation from LBBP.
- Conduction system pacing does not necessarily mask Brugada syndrome.
- Careful ECG interpretation and provocative testing remain vital in patients with suspected Brugada syndrome undergoing pacing.
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