title: Assessment of temperature, proximity, and course of the esophagus during radiofrequency ablation within the left atrium.
abstract: BACKGROUND
  Left atrioesophageal fistula is a devastating complication of atrial fibrillation ablation. There is no standard approach for avoiding this complication, which is caused by thermal injury during ablation. The objectives of this study were to evaluate the course of the esophagus and the temperature within the esophagus during pulmonary vein antrum isolation (PVAI) and correlate these data with esophagus tissue damage.
  
  
  RESULTS
  Eight-one patients presenting for PVAI underwent esophagus evaluation that included temperature probe placement. Esophagus course was obtained with computed tomography, 3D imaging (NAVX), or intracardiac echocardiography. For each lesion, the power, catheter and esophagus temperature, location, and presence of microbubbles were recorded. Lesion location and esophagus course were defined with 6 predetermined left atrial anatomic segments. Endoscopy evaluated tissue changes during and after PVAI. Of 81 patients, the esophagus coursed near the right pulmonary veins in 23 (28.4%), left pulmonary veins in 31 (38.3%), and mid-posterior wall in 27 (33%). Esophagus temperature was significantly higher during left atrial lesions along its course than with lesions elsewhere (38.9+/-1.4 degrees C, 36.8+/-0.5 degrees C, P<0.01). Lesions that generated microbubbles had higher esophagus temperatures than those without (39.3+/-1.5 degrees C, 38.5+/-0.9 degrees C, P<0.01). Power was not predictive of esophagus temperatures. Distance between the esophagus and left atrium was 4.4+/-1.2 mm.
  
  
  CONCLUSIONS
  Lesions near the course of the esophagus that generated microbubbles significantly increased esophagus temperature compared with lesions that did not. Power did not correlate with esophagus temperatures. Esophagus variability makes the avoidance of lesions along its course difficult. Rather than avoiding posterior lesions, emphasis could be placed on better esophagus monitoring for creation of safer lesions.
authors: Department of Cardiovascular Medicine, The Cleveland Clinic Foundation, Cleveland, OH 44195, USA.
authors: Jennifer E
authors: JE
authors: Cummings
authors: Robert A
authors: RA
authors: Schweikert
authors: Walid I
authors: WI
authors: Saliba
authors: J David
authors: JD
authors: Burkhardt
authors: Johannes
authors: J
authors: Brachmann
authors: Jens
authors: J
authors: Gunther
authors: Volker
authors: V
authors: Schibgilla
authors: Atul
authors: A
authors: Verma
authors: MarkAlain
authors: M
authors: Dery
authors: John L
authors: JL
authors: Drago
authors: Fethi
authors: F
authors: Kilicaslan
authors: Andrea
authors: A
authors: Natale
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000601:surgery*; D001831:Body Temperature; D017115:Catheter Ablation / Q000009:adverse effects*; D004947:Esophagus / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D006325:Heart Atria; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery*