title: Anatomy of the pulmonary veins in patients with atrial fibrillation and effects of segmental ostial ablation analyzed by computed tomography.
abstract: BACKGROUND
  The anatomic arrangement of pulmonary veins (PVs) is variable. No prior studies have quantitatively analyzed the effects of segmental ostial ablation on the PVs. The aim of this study was to determine the effect of segmental ostial radiofrequency ablation on PV anatomy in patients with atrial fibrillation (AF).
  
  
  RESULTS
  Three-dimensional models of the PVs were constructed from computed tomographic (CT) scans in 58 patients with AF undergoing segmental ostial ablation to isolate the PVs and in 10 control subjects without a history of AF. CT scans were repeated approximately 4 months later. PV and left atrial dimensions were measured with digital calipers. Four separate PV ostia were present in 47 subjects; 3 ostia were present in 2 subjects; and 5 ostia were present in 9 subjects. The superior PVs had a larger ostium than the inferior PVs. Patients with AF had a larger left atrial area between the PV ostia and larger ostial diameters than the controls. Segmental ostial ablation resulted in a 1.5 +/- 3.2 mm narrowing of the ostial diameter. A 28% to 61% focal stenosis was present 7.6 +/- 2.2 mm from the ostium in 3% of 128 isolated PVs. There were no instances of symptomatic PV stenosis during a mean follow-up of 245 +/- 105 days.
  
  
  CONCLUSIONS
  CT of the PVs allows identification of anatomic variants prior to catheter ablation procedures. Segmental ostial ablation results in a significant but small reduction in ostial diameter. Focal stenosis occurs infrequently and is attributable to delivery of radiofrequency energy within the PV.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109-0311, USA.
authors.forename: Christoph
authors.initials: C
authors.lastname: Scharf
authors.forename: Michael
authors.initials: M
authors.lastname: Sneider
authors.forename: Ian
authors.initials: I
authors.lastname: Case
authors.forename: Aman
authors.initials: A
authors.lastname: Chugh
authors.forename: Steve W K
authors.initials: SW
authors.lastname: Lai
authors.forename: Frank
authors.initials: F
authors.lastname: Pelosi
authors.forename: Bradley P
authors.initials: BP
authors.lastname: Knight
authors.forename: Ella
authors.initials: E
authors.lastname: Kazerooni
authors.forename: Fred
authors.initials: F
authors.lastname: Morady
authors.forename: Hakan
authors.initials: H
authors.lastname: Oral
mesh_terms: D001281:Atrial Fibrillation / Q000000981:diagnostic imaging / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care; D011300:Preoperative Care; D011667:Pulmonary Veins / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery*; D011859:Radiography; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity