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Updated: May 16, 2026

Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation
Published on: February 26, 2013
Decrease of the atrial fibrillatory rate, increased organization of the atrial rhythm and termination of atrial
Maria Aunes-Jansson1, Nils Edvardsson, Martin Stridh
1AstraZeneca R&D, Mölndal, Sweden. maria.aunes-jansson@astrazeneca.com
Background:
The atrial fibrillatory rate (AFR), on AZD7009 as compared to placebo, was investigated as a potential biomarker for electrophysiological effect in early antiarrhythmic drug development.
Methods:
Patients with permanent AF received infusions of AZD7009 and placebo in an exploratory two-way, single-blind, randomized cross-over study. The ECG was continuously recorded, and following QRST cancellation the AFR, its standard deviation (SD), the exponential decay and the atrial electrogram amplitude were determined as 3-min averages.
Results:
The mean AFR rapidly decreased by 43% from baseline (394 ± 38 to 225 ± 61 fibrillations/min, p=0.0003) on AZD7009, but not on placebo. The SD of the AFR and the exponential decay decreased in parallel. In 2 of 8 patients, termination of AF occurred after the AFR had decreased by 58% and 53%, respectively.
Conclusions:
The AFR may potentially serve as a biomarker of electrophysiological effects in early evaluation of rhythm control agents.
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