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Updated: Jun 1, 2026
09:17
High-Resolution Endocardial and Epicardial Optical Mapping in a Sheep Model of Stretch-Induced Atrial Fibrillation
Published on: July 29, 2011
What is the origin of this arrhythmia?
L Muresan1, C de Chillou, M Andronache
1Service de cardiologie, département d'électrophysiologie, institut Lorrain du coeur et des vaisseaux « Louis-Mathieu, Nancy, France. lmure san@yahoo.com
Annales De Cardiologie Et D'Angeiologie
|June 14, 2011
Summary
Inter-atrial epicardial connections can facilitate focal atrial tachycardias originating in pulmonary veins. Understanding these pathways is crucial for effective ablation and avoiding unnecessary procedures.
Area of Science:
- Electrophysiology
- Cardiac Anatomy
Background:
- Inter-atrial epicardial connections are known to influence supraventricular arrhythmias.
- Their specific role in focal atrial tachycardias (FATs) remains underexplored, particularly with advanced mapping technologies.
Observation:
- A case study of a 29-year-old woman with FAT originating from the right inferior pulmonary vein (RIPV).
- The tachycardia manifested with a right atrial (RA) origin due to electrical conduction via inter-atrial epicardial connections.
- Three-dimensional non-fluoroscopic mapping (CARTO) was used to create RA and left atrium activation maps.
Findings:
- Initial radiofrequency (RF) ablation at the earliest RA breakthrough site did not terminate the arrhythmia.
- Mapping revealed the earliest breakthrough at the RIPV ostium, where subsequent RF application successfully abolished the atrial tachycardia.
- This highlights the RIPV as the true origin, with inter-atrial connections mediating transseptal activation.
Implications:
- Inter-atrial epicardial connections can serve as a critical substrate for certain supraventricular arrhythmias.
- Electrophysiologists must be aware of these connections to accurately localize arrhythmia origins.
- Recognizing these pathways can prevent unnecessary RF applications in the posterior-septal RA, reducing procedural risks.
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