title: Use of three-dimensional computed tomography overlay for real-time cryoballoon ablation in atrial fibrillation reduces radiation dose and contrast dye.
abstract: OBJECTIVE
  Cryoballoon pulmonary vein (PV) isolation in patients with atrial fibrillation has proven to be effective in short-term and long-term follow-up. To visualise the PV anatomy, pre-ablation contrast pulmonary venography is commonly performed. Three-dimensional (3D) computed tomography (CT) overlay is a new technique creating a live 3D image of the left atrium by integrating a previously obtained CT scan during fluoroscopy. To evaluate the benefits of 3D CT overlay during cryoballoon ablation, we studied the use of 3D CT overlay versus contrast pulmonary venography in a randomised fashion in patients with paroxysmal atrial fibrillation undergoing cryoballoon PV isolation.
  
  
  RESULTS
  Between October 2012 and June 2013, 30 patients accepted for PV isolation were randomised to cryoballoon PV isolation using either 3D CT overlay or contrast pulmonary venography. All patients underwent a pre-procedural cardiac CT for evaluation of the anatomy of the left atrium (LA) and the PVs. In the 3D CT overlay group, a 3D reconstruction of the LA and PVs was made. An overlay of the CT reconstruction was then projected over live fluoroscopy. Patients in the contrast pulmonary venography group received significantly more contrast agent (77.1 ± 21.2 cc vs 40.1 ± 17.6 cc, p < 0.001) and radiation (43.0 ± 21.9 Gy.cm2 vs 28.41 ± 11.7 Gy.cm2, p = 0.04) than subjects in the 3D CT overlay group. There was no difference in total procedure time, fluoroscopy time and the amount of cryoapplications between the two groups.
  
  
  CONCLUSIONS
  The use of 3D CT overlay decreases radiation and contrast dye exposure and can assist in guiding cryoballoon-based PV isolation.
authors.affiliation: Thorax Centre Twente, Medisch Spectrum Twente, Enschede, The Netherlands. b.oudevelthuis@mst.nl.
authors.forename: B
authors.initials: B
authors.lastname: Oude Velthuis
authors.affiliation: Thorax Centre Twente, Medisch Spectrum Twente, Enschede, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Molenaar
authors.affiliation: Department of Cardiology, Bravis Ziekenhuis, Roosendaal, The Netherlands.
authors.forename: H G
authors.initials: HG
authors.lastname: Reinhart Dorman
authors.affiliation: Thorax Centre Twente, Medisch Spectrum Twente, Enschede, The Netherlands.
authors.forename: J Y
authors.initials: JY
authors.lastname: Stevenhagen
authors.affiliation: Thorax Centre Twente, Medisch Spectrum Twente, Enschede, The Netherlands.
authors.forename: M F
authors.initials: MF
authors.lastname: Scholten
authors.affiliation: Department of Research methodology, Methods and Data Analysis, University of Twente, Enschede, The Netherlands.|Medical School Twente, Medisch Spectrum Twente, Enschede, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: van der Palen
authors.affiliation: Thorax Centre Twente, Medisch Spectrum Twente, Enschede, The Netherlands.
authors.forename: J M
authors.initials: JM
authors.lastname: van Opstal
keywords: Ablation; Atrial fibrillation; Cryoballoon; Pulmonary vein isolation