title: Direct left atrial ICE imaging guided ablation for atrial fibrillation without employing contrast medium.
abstract: BACKGROUND
  Preoperative and intraoperative use of a contrast medium is unavoidable in catheter ablation for atrial fibrillation, which can become a particularly significant issue for patients suffering from renal impairment.
  
  
  OBJECTIVE
  The purpose of this study is to investigate the feasibility and safety of a technique for atrial fibrillation ablation without a contrast medium via intra-cardiac ultrasound imaging only.
  
  
  METHODS
  We prepared the geometry of the pulmonary vein and left atrium via a SOUNDSTAR catheter from inside the left atrium, without preoperative and intraoperative investigations using contrast mediums, for computed tomography or magnetic resonance imaging and pulmonary venography. This was followed by retrospective investigation of the success rate and complications observed in 200 successive paroxysmal and persistent atrial fibrillation cases that underwent catheter ablation from January 2011 to November 2012. The outcomes were assessed after the one-year follow-up.
  
  
  RESULTS
  Inserting a SOUNDSTAR catheter into the left atrium was successful in all cases, wherein rendering of all pulmonary veins and the left atrium was possible, and extensive encircling pulmonary vein isolation was successful in all cases. The sinus rhythm maintenance rate one year after the procedure was 90.4% for paroxysmal atrial fibrillation and 76.0% for persistent atrial fibrillation. The major complication rate was 0.5% (cardiac tamponade), with no cases presenting aggravation of renal function.
  
  
  CONCLUSIONS
  Atrial fibrillation ablation using an intra-cardiac ultrasound from the left atrium without employing a contrast medium was safe, with no adverse effects on renal function.
authors.affiliation: Department of Cardiovascular Medicine, The University of Tokyo, Japan.
authors.forename: Takumi J
authors.initials: TJ
authors.lastname: Matsubara
authors.affiliation: Department of Cardiovascular Medicine, The University of Tokyo, Japan; Department of Ubiquitous Health Informatics, The University of Tokyo, Japan. Electronic address: fujiu-tky@umin.ac.jp.
authors.forename: Katsuhito
authors.initials: K
authors.lastname: Fujiu
authors.affiliation: Department of Cardiovascular Medicine, The University of Tokyo, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Asada
authors.affiliation: Department of Cardiovascular Medicine, The University of Tokyo, Japan.
authors.forename: Toshiya
authors.initials: T
authors.lastname: Kojima
authors.affiliation: Department of Cardiovascular Medicine, The University of Tokyo, Japan.
authors.forename: Makimoto
authors.initials: M
authors.lastname: Hisaki
authors.affiliation: Department of Cardiovascular Medicine, The University of Tokyo, Japan.
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Yamagata
authors.affiliation: Department of Cardiovascular Medicine, The University of Tokyo, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Shimizu
authors.affiliation: Department of Cardiovascular Medicine, The University of Tokyo, Japan.
authors.forename: Eriko
authors.initials: E
authors.lastname: Hasumi
authors.affiliation: Department of Cardiovascular Medicine, The University of Tokyo, Japan.
authors.forename: Hatano
authors.initials: H
authors.lastname: Masaru
authors.affiliation: Department of Cardiovascular Medicine, The University of Tokyo, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Akazawa
authors.affiliation: Department of Cardiovascular Medicine, The University of Tokyo, Japan.
authors.forename: Issei
authors.initials: I
authors.lastname: Komuro
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D003287:Contrast Media; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery; D012189:Retrospective Studies; D025321:Surgery, Computer-Assisted / Q000379:methods*; D013997:Time Factors; D018084:Ultrasonography, Interventional / Q000379:methods*
chemical_list: D003287:Contrast Media
keywords: Atrial fibrillation; CARTOSOUND; Catheter ablation; Intra-cardiac ultrasound; No contrast medium; Pulmonary vein isolation