title: Pulmonary vein isolation using transvenous catheter cryoablation for treatment of atrial fibrillation without risk of pulmonary vein stenosis.
abstract: OBJECTIVE
  We sought to evaluate the efficacy and safety of pulmonary vein (PV) isolation using transvenous cryoablation for the treatment of atrial fibrillation (AF).
  
  
  BACKGROUND
  Although electrical isolation of PVs with radiofrequency energy for the treatment of AF is feasible, it is associated with a significant risk of PV stenosis. Cryoablation is a new alternative therapy allowing ablation of tissue while preserving its underlying architecture.
  
  
  METHODS
  In 52 patients with paroxysmal (n = 45) or persistent (n = 7) AF, PV isolation using the CryoCor cryoablation system (CyroCor Inc., San Diego, California) with a 10F deflectable transvenous catheter was performed as guided by ostial PV potentials. Cryoablation was applied twice at each targeted site (2.5 to 5 min/application). Computed tomography (CT) of the thorax was performed at baseline and at 3 and 12 months to evaluate for PV stenosis.
  
  
  RESULTS
  All targeted PVs were completely isolated in 49 (94%) of 52 of patients. Of 152 PVs targeted, 147 (97%) were successfully isolated (mean 3.0 PVs isolated per patient). After a mean period of 12.4 +/- 5.5 months of follow-up, 37 (71%) of 52 patients had no recurrence of AF or were clinically improved, including 29 patients (56%) who had no recurrence of AF with (n = 11) or without the use of anti-arrhythmic drugs. At 3 and 12 months, the CT scan showed no evidence of PV stenosis associated with cryoablation in any patients.
  
  
  CONCLUSIONS
  Transvenous catheter cryoablation is an effective method to create PV electrical isolation for the treatment of AF. A clinically satisfactory result can be achieved in 71% of patients with AF, without the risk of PV stenosis.
authors.affiliation: Department of Medicine, University of Hong Kong, Queen Mary Hospital, Hong Kong, China. hftes@hkucc.hku.hk
authors.forename: Hung-Fat
authors.initials: HF
authors.lastname: Tse
authors.forename: Sven
authors.initials: S
authors.lastname: Reek
authors.forename: Carl
authors.initials: C
authors.lastname: Timmermans
authors.forename: Kathy Lai-Fun
authors.initials: KL
authors.lastname: Lee
authors.forename: J Christoph
authors.initials: JC
authors.lastname: Geller
authors.forename: Luz-Maria
authors.initials: LM
authors.lastname: Rodriguez
authors.forename: Benoit
authors.initials: B
authors.lastname: Ghaye
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Ayers
authors.forename: Harry J G M
authors.initials: HJ
authors.lastname: Crijns
authors.forename: Helmut U
authors.initials: HU
authors.lastname: Klein
authors.forename: Chu-Pak
authors.initials: CP
authors.lastname: Lau
mesh_terms: D000328:Adult; D001281:Atrial Fibrillation / Q000601:surgery*; D002404:Catheterization / Q000379:methods; D003251:Constriction, Pathologic / Q000517:prevention & control; D003452:Cryosurgery / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000473:pathology / Q000601:surgery*; D016896:Treatment Outcome