title: Safety and Efficacy of Cryoballoon Ablation for Paroxysmal Atrial Fibrillation in Japan　- Results From the Japanese Prospective Post-Market Surveillance Study.
abstract: BACKGROUND
  Outcomes of cryoballoon ablation for paroxysmal atrial fibrillation (PAF) have been reported in the Western countries but not in Japan. The CRYO-Japan PMS study was a single-arm, observational, multicenter, prospective study of the 2nd-generation cryoballoon Arctic Front Advance(TM). We evaluated device- and procedure-related complications and clinical outcomes at 6 months.
  
  
  RESULTS
  The 616 patients (male, 72%; mean age, 63±11 years) were enrolled from 33 Japanese hospitals. Of all patients, 610 had PAF, and procedural data were analyzed in 607. A subset of 328 patients was followed for 6 months for the primary efficacy analysis. AF recurrence outside the 3-month blanking period or repeat ablation was considered treatment failure. Pulmonary vein isolation was achieved in 606/607 patients (99.8%); 1 patient (0.3%) had a repeat ablation during the blanking period. Freedom from AF at 6 months was 88.4% (95% CI: 84.1-91.6%). Device- and/or procedure-related adverse events included phrenic nerve injury unresolved at hospital discharge in 9/616 patients (1.5%), which resolved within 6 months in 7, pericardial effusion in 5/616 (0.8%), and tamponade in 4/616 (0.6%). One non-device-related death from pneumonia was reported 6 days post-procedure.
  
  
  CONCLUSIONS
  Cryoballoon ablation is safe and effective for Japanese PAF patients, with 88.4% AF freedom at 6 months post-ablation. (Circ J 2016; 80: 1744-1749).
authors.affiliation: Department of Cardiology, Hirosaki University Graduate School of Medicine.
authors.forename: Ken
authors.initials: K
authors.lastname: Okumura
authors.forename: Kazuo
authors.initials: K
authors.lastname: Matsumoto
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: Akihiko
authors.initials: A
authors.lastname: Nogami
authors.forename: Robert B
authors.initials: RB
authors.lastname: Hokanson
authors.forename: Fred
authors.initials: F
authors.lastname: Kueffer
mesh_terms: D000368:Aged; D044466:Asian People; D001281:Atrial Fibrillation / Q000453:epidemiology / Q000503:physiopathology / Q000601:surgery*; D003452:Cryosurgery / Q000009:adverse effects / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011358:Product Surveillance, Postmarketing; D011446:Prospective Studies; D012449:Safety