title: Usefulness of transesophageal echocardiography in the isolation of pulmonary veins in the treatment of atrial fibrillation.
abstract: BACKGROUND
  New imaging strategies for atrial fibrillation (AF) ablation should enhance the safety of this technique. The role of transesophageal echocardiography (TEE) in this setting has not been prospectively evaluated.
  
  
  METHODS
  Under general anesthesia, 85 patients underwent TEE-guided AF ablation. A hybrid technique was performed with circular pulmonary veins (PV) lesions and antrum and ostial electrical isolation guided by TEE. TEE excluded left atrial (LA) thrombus, guided transseptal puncture and catheter positioning, and helped to identify PV ostia and their velocities. The TEE probe localized the esophagus, its temperature (T degrees ) and micro bubbles formation.
  
  
  RESULTS
  Overall, one patient had a LA clot. The esophagus was located close to left PV in 38%, the right PV in 28%, midline in 17% and with an oblique course in 17% of patients. Right and left superior PV velocities were detected in 100%, left inferior PV in 88% and right inferior PV in 82% of patients. Microbubbles were detected in 9 patients (11%). Elevation of TEE T degrees occurred in 14 patients (16%) and was regularly observed when lesions were applied over the TEE probe shadow, in close proximity to the posterior wall. Two major complications (1 tamponade, 1 PV laceration) occurred and were detected early by TEE.
  
  
  CONCLUSIONS
  TEE offers advantages compared to a map-guided only approach. It is a reliable tool to assess esophagus T degrees and localization, guide transseptal puncture, delineate the PV ostia, and monitor complications.
authors.affiliation: Institut Universitaire de cardiologie et pneumologie de l'Université Laval, Laval Hospital, Quebec City, Quebec, Canada. jean.champagne@med.ulaval.ca
authors.forename: Jean
authors.initials: J
authors.lastname: Champagne
authors.forename: Najmeddine
authors.initials: N
authors.lastname: Echahidi
authors.forename: François
authors.initials: F
authors.lastname: Philippon
authors.forename: André
authors.initials: A
authors.lastname: St-Pierre
authors.forename: Franck
authors.initials: F
authors.lastname: Molin
authors.forename: Louis
authors.initials: L
authors.lastname: Blier
authors.forename: Marcel
authors.initials: M
authors.lastname: Gilbert
authors.forename: Jacques
authors.initials: J
authors.lastname: Villeneuve
authors.forename: Dania
authors.initials: D
authors.lastname: Mohty
authors.forename: Gilles
authors.initials: G
authors.lastname: O'hara
mesh_terms: D000328:Adult; D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D017548:Echocardiography, Transesophageal; D004947:Esophagus / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000000981:diagnostic imaging / Q000601:surgery; D013696:Temperature