title: Accuracy of intracardiac echocardiography for assessing the esophageal course along the posterior left atrium: a comparison to magnetic resonance imaging.
abstract: BACKGROUND
  Atrioesophageal fistula is a potentially fatal complication of ablation in the left atrium (LA) to treat atrial fibrillation.
  
  
  OBJECTIVE
  The objective of our study was to systematically evaluate the diagnostic potential of intracardiac echocardiography (ICE) for accurately assessing the esophageal course along the posterior LA.
  
  
  METHODS
  Thirty-five patients underwent magnetic resonance imaging (MRI) before and ICE during pulmonary vein (PV) isolation to visualize the esophagus. The location of the esophagus was determined in relation to the PVs and anatomic regions of the LA by both ICE and MRI. Using the MRI images as a reference, the accuracy of ICE localization was assessed.
  
  
  RESULTS
  The most common location for the esophagus to appear was the mid-posterior wall (80% of patients by ICE, 71% of patients by MRI), followed by the left posterior wall (71% of patients by ICE, 63% of patients by MRI) and the right posterior wall (60% of patients by ICE, 51% of patients by MRI). The esophagus was seen to course near the left PV antrums (left superior PV antrum 34% of patients by ICE and MRI; left inferior PV antrum 34% of patients by ICE, 37% of patients by MRI), left superior PV (17% of patients by ICE, 20% of patients by MRI), left inferior PV (17% of patients by ICE and MRI), right inferior PV antrum (29% of patients by ICE, 37% of patients by MRI) and the right inferior PV (3% of patients by ICE, 17% of patients by MRI). The sensitivity for esophageal location by ICE compared to that by MRI ranged between 33% (right inferior PV) and 92% (left superior PV antrum, left inferior PV antrum, and mid-posterior wall). The specificity for esophageal location by ICE compared to that by MRI ranged between 60% (mid-posterior wall) and 100% (right inferior PV). The positive predictive value ranged between 80% (left inferior PV) and 100% (right inferior PV). The negative predictive value ranged between 84% (right inferior PV antrum) and 96% (left superior PV antrum).
  
  
  CONCLUSIONS
  Phased array ICE provides rapid, real-time localization of the esophagus during LA ablation that is comparable to MRI.
authors.affiliation: Division of Cardiology, Virginia Commonwealth University Medical Center, Richmond, Virginia 23298-0053, USA.
authors.forename: David N
authors.initials: DN
authors.lastname: Kenigsberg
authors.forename: Benjamin P
authors.initials: BP
authors.lastname: Lee
authors.forename: John D
authors.initials: JD
authors.lastname: Grizzard
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Ellenbogen
authors.forename: Mark A
authors.initials: MA
authors.lastname: Wood
mesh_terms: D001281:Atrial Fibrillation / Q000628:therapy; D006328:Cardiac Catheterization / Q000379:methods; D004452:Echocardiography / Q000379:methods*; D004947:Esophagus / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D005260:Female; D006325:Heart Atria / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity