Is It Necessary to Achieve a Complete Box Isolation in the Case of Frequent Esophageal Temperature Rises? Feasibility of Shifting to a Partial Box Isolation Strategy for Patients With Non-Paroxysmal Atrial Fibrillation

• Published in: Journal of cardiovascular electrophysiology Vol. 27; no. 8; pp. 897 - 904
• Main Authors: HIGUCHI, SATOSHI, SOHARA, HIROSHI, NAKAMURA, YOSHINORI, IHARA, MINORU, YAMAGUCHI, YOSHIO, SHODA, MORIO, HAGIWARA, NOBUHISA, SATAKE, SHUTARO
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01-08-2016; Wiley Subscription Services, Inc
• Subjects: Action Potentials; Aged; atrial fibrillation; Atrial Fibrillation - diagnosis; Atrial Fibrillation - physiopathology; Atrial Fibrillation - surgery; Body Temperature Regulation; Box isolation lesions; catheter ablation; Catheter Ablation - adverse effects; Catheter Ablation - methods; Disease-Free Survival; Electrophysiologic Techniques, Cardiac; esophageal lesions; Esophagus - physiopathology; Esophagus - surgery; Feasibility Studies; Female; Heart Atria - physiopathology; Heart Atria - surgery; Heart Rate; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Monitoring, Intraoperative - instrumentation; Monitoring, Intraoperative - methods; pulmonary vein isolation; Pulmonary Veins - physiopathology; Pulmonary Veins - surgery; Recurrence; Retrospective Studies; Thermometers; Time Factors; Treatment Outcome; esophageal lesions; atrial fibrillation; catheter ablation; Box isolation lesions; pulmonary vein isolation
• ISSN: 1045-3873; 1540-8167
• DOI: 10.1111/jce.13000

Partial Box Isolation Strategy for Non‐Paroxysmal Atrial Fibrillation
Introduction
There are some cases with frequent luminal esophageal temperature (LET) rises despite titrating the radiofrequency energy while creating a linear lesion for the Box isolation of atrial fibrillation (AF). Little is known about the feasibility of redesigning the ablation lines for a modified Box isolation strategy to prevent fatal esophageal injury in those cases.
Methods and Results
Two hundred and seventeen patients who underwent a Box isolation of non‐paroxysmal AF were evaluated. We divided them into 2 groups, patients in whom a box lesion set of the entire posterior left atrium had been achieved (complete Box isolation [CBI]; n = 157) and those in whom 2 additional peri‐esophageal vertical lines were created at both the right and left ends of the esophagus, and those areas were left with an incomplete isolation when frequent rapid LET rises above 39.0 °C were observed while creating the floor line (partial Box isolation [PBI]; n = 60). During 20.1 ± 13.9 months of follow‐up, the arrhythmia‐free rates were 54.1% in the CBI group versus 48.3% in the PBI group (P = 0.62). In the second session, a complete Box isolation was highly achieved even in the PBI group (94.3% vs. 83.3%, respectively; P = 0.17) and after 2 procedures, the arrhythmia‐free rates increased to 75.2% vs. 68.3%, respectively (P = 0.34). There was no symptomatic esophageal injury in the PBI group.
Conclusion
In the case of frequent LET rises while creating the linear lesions for the Box isolation strategy for non‐paroxysmal AF, shifting to the PBI strategy was feasible.