Related Experiment Video
Updated: Jun 29, 2025

Optimization of Transesophageal Atrial Pacing to Assess Atrial Fibrillation Susceptibility in Mice
Published on: June 29, 2022
2:1 electronic AV block due to inappropriate automatic post‐ventricular atrial refractory period extension
Pasquale Crea1, Paolo Bellocchi1, Federica Cocuzza1
1Department of Clinical and Experimental Medicine-Cardiology Unit, University of Messina, Messina, Italy.
Abstract:
A 16-year-old female with dual-chamber pacemaker (Medtronic Azure XT DR), due to symptomatic third-degree congenital atrioventricular (AV) block, presented to our ambulatory with dizziness and presyncopal episodes preceded by prodromes, occurring over the last few months. The device was programmed in DDD mode with an upper rate of 150 bpm. A head-up Tilt Test (HUTT) revealed the unexpected emergence of 2:1 electronic AV block at a sinus rate of 130 bpm.
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