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Updated: Jun 26, 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
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.
Abstract:
A 67-year-old man with recurrent syncope and chronic right bundle branch block underwent left bundle branch pacing for infra-Hisian atrioventricular block. Because a prior electrocardiogram showed a type 2 Brugada pattern, an ajmaline challenge was performed after device implantation using high-precordial lead positioning. The test unmasked a diagnostic type 1 Brugada pattern during both intrinsic and left bundle branch block-paced beats. This case illustrates that diagnostic Brugada repolarization abnormalities may remain recognizable despite altered ventricular activation associated with conduction system pacing.
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