title: Effectiveness of esophagus detection by three-dimensional electroanatomical mapping to avoid esophageal injury during ablation of atrial fibrillation.
abstract: OBJECTIVE
  Esophageal-left atrial (LA) fistula during atrial fibrillation (AF) ablation is a fatal event. We explored the relation of the esophagus-to-ablated point distance and esophageal temperature rise.
  
  
  METHODS
  Consecutive patients (n=106) underwent complex fractionated atrial electrogram-guided AF ablation using CartoMerge; the pulmonary veins were isolated in 23 patients. Maximum radiofrequency (RF) power near the esophagus was 15 W. Ablated points with esophageal temperature rise (monitored with a probe) to ≥38.0°C were tagged; if ≥39.0°C, RF was discontinued.
  
  
  RESULTS
  Of 1647 ablated points near the esophagus, 274 were associated with a temperature rise to 38.0-38.9°C and 241 points to ≥39.0°C. Distances (mm) from points to esophagus were 5.1 ± 0.6 (no rise), 4.2±3.1 (38.0-38.9°C), 2.9 ± 2.5 (≥39.0°C). Altogether, 15.5% of points in the upper LA posterior wall, 41.5% in the middle, and 30.2% in the lower caused rises to ≥38.0°C; 8.7%, 24.6%, and 11.0% caused rises to ≥39.0°C. The middle wall was most affected (p<0.01), as shown by multiple logistic regression analysis (both temperatures). Points causing a rise increased significantly as distance decreased (p<0.001). The odds ratio for rise to ≥38.0°C compared with <4.0 to >5.0 mm distance was 2.28 (p=0.004). The longest distance for ≥38.0°C rise was 18.5 mm.
  
  
  CONCLUSIONS
  Distance is an important predictor of esophageal temperature rise. The middle LA posterior wall is most vulnerable. A dose of 15 W is too high for ablation, especially <4.0 mm from the esophagus. Points >20.0 mm away are relatively safe.
authors.affiliation: Clinical Laboratory Unit, Kagoshima University Hospital, Japan.
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Maenosono
authors.forename: Naoya
authors.initials: N
authors.lastname: Oketani
authors.forename: Sanemasa
authors.initials: S
authors.lastname: Ishida
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Iriki
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Ichiki
authors.forename: Hideki
authors.initials: H
authors.lastname: Okui
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ninomiya
authors.forename: Shuichi
authors.initials: S
authors.lastname: Hamasaki
authors.forename: Fuminori
authors.initials: F
authors.lastname: Namino
authors.forename: Masakaze
authors.initials: M
authors.lastname: Matsushita
authors.forename: Chuwa
authors.initials: C
authors.lastname: Tei
authors.forename: Teruto
authors.initials: T
authors.lastname: Hashiguchi
mesh_terms: D001281:Atrial Fibrillation / Q000601:surgery*; D001831:Body Temperature; D017115:Catheter Ablation / Q000009:adverse effects* / Q000379:methods; D004937:Esophageal Fistula / Q000517:prevention & control; D004947:Esophagus / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000293:injuries; D005260:Female; D005402:Fistula / Q000517:prevention & control; D006331:Heart Diseases / Q000517:prevention & control; D006801:Humans; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed