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Updated: Sep 26, 2026

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Published on: July 3, 2013
Excitable gap composition in the presence of antiarrhythmic drugs in common human atrial flutter
Elise Jalil1, Boualem Mensour, Alain Vinet
1The Research Center of Sacré-Coeur Hospital, Montréal, Québec.
Background And Objective:
Recurrence of atrial flutter (AFl) on antiarrhythmic drugs is frequently observed. To determine the reasons for drug inefficacy, the electrophysiological parameters of AFl were studied in eight patients without drug, six patients on sotalol (Sot), eight patients on amiodarone (Amio) and four patients on propafenone (PPF) who presented to the electrophysiology laboratory for conversion of AFl by rapid atrial pacing.
Methods:
A quadripolar electrode catheter was positioned in the right atrium in the pathway of the AFl circuit. The duration and composition of the excitable gap (EG) were determined by premature stimuli during AFl.
Results:
The EG in AFl recurring on Sot (80 +/- 25 ms), Amio (78 +/- 13 ms) and PPF (83 +/- 26 ms) was not significantly different from that without drug (88 +/- 14 ms). Furthermore, a fully excitable portion of the EG was present whether with or without drug.
Conclusions:
AFl recurrence on Amio, PPF or Sot is associated with the continued presence of an EG and fully excitable portion. These findings explain the persistent viability of the AFl circuit despite drug therapy in these patients.
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