title: Anatomical Evaluation of the Pulmonary Veins and the Left Atrium Using Computed Tomography Before Catheter Ablation: Reproducibility of Measurements.
abstract: BACKGROUND
  Atrial fibrillation (AF) is a common supraventricular arrhythmia. ECG-gated MDCT seems to be currently a method of choice for pre-ablation anatomical mapping due to an excellent resolution and truly isotropic three-dimensional nature. The aim of this study was to establish the between-subject variability and inter-observer reproducibility of anatomical evaluation of the pulmonary veins (PV) and the left atrium (LA) using computed tomography.
  
  
  METHODS
  A retrospective analysis included 42 patients with AF, who were scheduled for a cardiac CT for ablation planning. Images were assessed by two independent radiologists using a semi-automatic software tool. The left atrium anatomy (volume, AP diameter), anatomy of the pulmonary veins (number, ostia diameters and surface area) were evaluated. The relative between-subject variability and the inter-observer variability of measurements were calculated.
  
  
  RESULTS
  The heart rate during scanning ranged from 50 to 133/min. (mean 79.1/min.) and all examinations were of adequate image quality. Accessory pulmonary veins were found in 24% of patients. Between-subject variability of the PV ostial cross-sectional area ranged from 33% to 48%. The variability of the left atrium size was 21% for the diameter and 35% for the volume. The inter-observer agreement for the detection of accessory pulmonary veins was good (κ=0.73; 95% CI, 0.54-0.93).
  
  
  CONCLUSIONS
  Between-subject variability of the pulmonary vein ostial cross-sectional area and the left artial volume is substantial. The anatomical assessment of the pulmonary vein ostia and the left atrium size in computed tomography presents a good inter-observer reproducibility.
authors.affiliation: Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, Bydgoszcz, Poland.
authors.forename: Przemysław
authors.initials: P
authors.lastname: Ratajczak
authors.affiliation: Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, Bydgoszcz, Poland.
authors.forename: Agata
authors.initials: A
authors.lastname: Sławińska
authors.affiliation: Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, Bydgoszcz, Poland.
authors.forename: Ida
authors.initials: I
authors.lastname: Martynowska-Rymer
authors.affiliation: Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, Bydgoszcz, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Strześniewski
authors.affiliation: Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, Bydgoszcz, Poland.
authors.forename: Grażyna
authors.initials: G
authors.lastname: Rusak
keywords: Atrial Fibrillation; Heart Atria; Multidetector Computed Tomography