title: Atrial fibrillation: multi-detector row CT of pulmonary vein anatomy prior to radiofrequency catheter ablation--initial experience.
abstract: OBJECTIVE
  To evaluate multi-detector row computed tomographic (CT) depiction of pulmonary veins to provide a road map for radiofrequency catheter ablation.
  
  
  METHODS
  For patients, institutional review board (IRB) approval was not required, and consent was obtained for treatment. Control subjects were part of an IRB-approved research protocol at the institution, in which they had consented to participate. Multi-detector row CT was performed in 23 patients (17 men, six women; mean age, 48 years +/- 11 [standard deviation]) with atrial fibrillation who were admitted for isolation of pulmonary veins by means of radiofrequency catheter ablation. Pulmonary vein anatomy was evaluated, and diameters of pulmonary vein ostia were measured. To determine the shape of ostia, a venous ostium index was calculated for all veins by dividing anterior-posterior measurements by superior-inferior measurements. Results were compared with those in a control group of 11 patients (eight men, three women; mean age, 56 years +/- 11) without atrial fibrillation. Images were evaluated by two observers in consensus.
  
  
  RESULTS
  Pulmonary veins additional to the four main veins were found in seven (30%) of 23 patients. Common ostia of left and right pulmonary veins were detected in 19 (83%) and nine (39%) patients, respectively. Early branching occurred more often with right than with left veins (19 [83%] vs three [13%] cases, P <.05) in both patients and control subjects. Anterior-posterior diameter of ostia was 12.8 mm +/- 3.3 for left veins, 16.2 mm +/- 3.8 for right veins, and 18.8 mm +/- 7.7 and 28.7 mm +/- 5.1 for left and right common ostia, respectively. Ostia of right pulmonary veins were more round than were ostia of left pulmonary veins (venous ostium index in patients, 0.91 +/- 0.21 vs 0.75 +/- 0.17, P <.05; in control subjects, 0.93 +/- 0.12 vs 0.82 +/- 0.17, P <.05). The CT data were used to determine ablation strategy and guide catheters during radiofrequency ablation.
  
  
  CONCLUSIONS
  Multi-detector row CT provides a valuable road map for pulmonary vein anatomy prior to radiofrequency catheter ablation. Variations in number and insertion of pulmonary veins were observed in a considerable number of patients and control subjects.
authors.affiliation: Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, the Netherlands.
authors.forename: Monique R M
authors.initials: MR
authors.lastname: Jongbloed
authors.forename: Martijn S
authors.initials: MS
authors.lastname: Dirksen
authors.forename: Jeroen J
authors.initials: JJ
authors.lastname: Bax
authors.forename: Eric
authors.initials: E
authors.lastname: Boersma
authors.forename: Koos
authors.initials: K
authors.lastname: Geleijns
authors.forename: Hildo J
authors.initials: HJ
authors.lastname: Lamb
authors.forename: Ernst E
authors.initials: EE
authors.lastname: van der Wall
authors.forename: Albert
authors.initials: A
authors.lastname: de Roos
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Schalij
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging* / Q000601:surgery; D016022:Case-Control Studies; D017115:Catheter Ablation; D003287:Contrast Media; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D007472:Iohexol / Q000031:analogs & derivatives*; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; C093233:iobitridol; D007472:Iohexol