title: Time-resolved three-dimensional imaging of the left atrium and pulmonary veins in the interventional suite--a comparison between multisweep gated rotational three-dimensional reconstructed fluoroscopy and multislice computed tomography.
abstract: BACKGROUND
  Cardiac computed tomography (CT) is commonly used to visualize left atrial (LA) anatomy for ablation of atrial fibrillation. We have developed a new imaging technique that allows acquisition and visualization of three-dimensional (3D) cardiac images in the catheter lab.
  
  
  OBJECTIVE
  We sought to compare LA and pulmonary vein (PV) dimensions acquired using gated multisweep rotational fluoroscopy (C-arm CT) system and multislice computed tomography (MSCT) in an in vivo porcine model.
  
  
  METHODS
  A Siemens AXIOM Artis dTA C-arm system (Siemens AG, Medical Solutions) was modified to allow acquisition of four bidirectional sweeps during synchronized acquisition of the electrocardiogram signal to allow retrospective gating. C-arm CT image volumes were then reconstructed. Gated MSCT (SOMATOM Sensation 16 and 64, Siemens AG, Medical Solutions) and C-arm CT images were acquired in six animals. The two main PV diameters were measured in orthogonal axes. LA volumes were calculated. C-arm CT measurements were compared with the MSCT measurements.
  
  
  RESULTS
  The average PV diameters using the C-arm CT were 2.24 x 1.35 cm, versus 2.27 x 1.38 cm for CT. The average difference was 0.034 cm (1.9%) between the C-arm CT and standard CT. The average LA volume using MSCT was 49.1 +/- 12.7 cm(3), as compared with 51.0 +/- 8.7 cm(3) obtained by the C-arm CT. The average difference between the C-arm CT and the MSCT was 1.9 cm(3) (3.7%). There were no significant differences in either the PV or LA measurements.
  
  
  CONCLUSIONS
  Visualization of 3D cardiac anatomy during ablation procedures is possible and highly accurate. The 3D cardiac reconstructions acquired during ablation procedures will be valuable for procedural planning and guidance.
authors: Cardiac Arrhythmia Service, Stanford University Medical School, Stanford, California, USA. aalahmad@cvmed.stanford.edu
authors: Amin
authors: A
authors: Al-Ahmad
authors: Lars
authors: L
authors: Wigström
authors: Dominique
authors: D
authors: Sandner-Porkristl
authors: Paul J
authors: PJ
authors: Wang
authors: Paul C
authors: PC
authors: Zei
authors: Jan
authors: J
authors: Boese
authors: Günter
authors: G
authors: Lauritsch
authors: Teri
authors: T
authors: Moore
authors: Frandics
authors: F
authors: Chan
authors: Rebecca
authors: R
authors: Fahrig
mesh_terms: D000818:Animals; D001281:Atrial Fibrillation / Q000628:therapy*; D017115:Catheter Ablation; D005471:Fluoroscopy / Q000295:instrumentation*; D006325:Heart Atria / Q000000981:diagnostic imaging / Q000473:pathology*; D021621:Imaging, Three-Dimensional / Q000379:methods; D011667:Pulmonary Veins / Q000000981:diagnostic imaging / Q000473:pathology*; D013552:Swine; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods; D014463:Ultrasonography