title: Cryoballoon or Radiofrequency Ablation for Paroxysmal Atrial Fibrillation.
abstract: BACKGROUND
  Current guidelines recommend pulmonary-vein isolation by means of catheter ablation as treatment for drug-refractory paroxysmal atrial fibrillation. Radiofrequency ablation is the most common method, and cryoballoon ablation is the second most frequently used technology.
  
  
  METHODS
  We conducted a multicenter, randomized trial to determine whether cryoballoon ablation was noninferior to radiofrequency ablation in symptomatic patients with drug-refractory paroxysmal atrial fibrillation. The primary efficacy end point in a time-to-event analysis was the first documented clinical failure (recurrence of atrial fibrillation, occurrence of atrial flutter or atrial tachycardia, use of antiarrhythmic drugs, or repeat ablation) following a 90-day period after the index ablation. The noninferiority margin was prespecified as a hazard ratio of 1.43. The primary safety end point was a composite of death, cerebrovascular events, or serious treatment-related adverse events.
  
  
  RESULTS
  A total of 762 patients underwent randomization (378 assigned to cryoballoon ablation and 384 assigned to radiofrequency ablation). The mean duration of follow-up was 1.5 years. The primary efficacy end point occurred in 138 patients in the cryoballoon group and in 143 in the radiofrequency group (1-year Kaplan-Meier event rate estimates, 34.6% and 35.9%, respectively; hazard ratio, 0.96; 95% confidence interval [CI], 0.76 to 1.22; P<0.001 for noninferiority). The primary safety end point occurred in 40 patients in the cryoballoon group and in 51 patients in the radiofrequency group (1-year Kaplan-Meier event rate estimates, 10.2% and 12.8%, respectively; hazard ratio, 0.78; 95% CI, 0.52 to 1.18; P=0.24).
  
  
  CONCLUSIONS
  In this randomized trial, cryoballoon ablation was noninferior to radiofrequency ablation with respect to efficacy for the treatment of patients with drug-refractory paroxysmal atrial fibrillation, and there was no significant difference between the two methods with regard to overall safety. (Funded by Medtronic; FIRE AND ICE ClinicalTrials.gov number, NCT01490814.).
authors.affiliation: From the Department of Cardiology, Asklepios Klinik St. Georg, Hamburg (K.-H.K., A.M., F.O.), Cardioangiologisches Centrum Bethanien, Medical Department III am Markus Krankenhaus, Frankfurt (A.F., J.C.), Herz-Zentrum, Bad Krozingen (T.A.), and Technische Universität Dresden, Dresden (K.B.) - all in Germany; Hospital Clinic, University of Barcelona, Barcelona (J.B.); Isala Klinieken, Zwolle, the Netherlands (A.E.); London School of Hygiene and Tropical Medicine, London (S.J.P.); Clinique Pasteur, Toulouse, France (J.-P.A.); and Centro Cardiologico Monzino, University of Milan, Milan (C.T.).
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Kuck
authors.affiliation: From the Department of Cardiology, Asklepios Klinik St. Georg, Hamburg (K.-H.K., A.M., F.O.), Cardioangiologisches Centrum Bethanien, Medical Department III am Markus Krankenhaus, Frankfurt (A.F., J.C.), Herz-Zentrum, Bad Krozingen (T.A.), and Technische Universität Dresden, Dresden (K.B.) - all in Germany; Hospital Clinic, University of Barcelona, Barcelona (J.B.); Isala Klinieken, Zwolle, the Netherlands (A.E.); London School of Hygiene and Tropical Medicine, London (S.J.P.); Clinique Pasteur, Toulouse, France (J.-P.A.); and Centro Cardiologico Monzino, University of Milan, Milan (C.T.).
authors.forename: Josep
authors.initials: J
authors.lastname: Brugada
authors.affiliation: From the Department of Cardiology, Asklepios Klinik St. Georg, Hamburg (K.-H.K., A.M., F.O.), Cardioangiologisches Centrum Bethanien, Medical Department III am Markus Krankenhaus, Frankfurt (A.F., J.C.), Herz-Zentrum, Bad Krozingen (T.A.), and Technische Universität Dresden, Dresden (K.B.) - all in Germany; Hospital Clinic, University of Barcelona, Barcelona (J.B.); Isala Klinieken, Zwolle, the Netherlands (A.E.); London School of Hygiene and Tropical Medicine, London (S.J.P.); Clinique Pasteur, Toulouse, France (J.-P.A.); and Centro Cardiologico Monzino, University of Milan, Milan (C.T.).
authors.forename: Alexander
authors.initials: A
authors.lastname: Fürnkranz
authors.affiliation: From the Department of Cardiology, Asklepios Klinik St. Georg, Hamburg (K.-H.K., A.M., F.O.), Cardioangiologisches Centrum Bethanien, Medical Department III am Markus Krankenhaus, Frankfurt (A.F., J.C.), Herz-Zentrum, Bad Krozingen (T.A.), and Technische Universität Dresden, Dresden (K.B.) - all in Germany; Hospital Clinic, University of Barcelona, Barcelona (J.B.); Isala Klinieken, Zwolle, the Netherlands (A.E.); London School of Hygiene and Tropical Medicine, London (S.J.P.); Clinique Pasteur, Toulouse, France (J.-P.A.); and Centro Cardiologico Monzino, University of Milan, Milan (C.T.).
authors.forename: Andreas
authors.initials: A
authors.lastname: Metzner
authors.affiliation: From the Department of Cardiology, Asklepios Klinik St. Georg, Hamburg (K.-H.K., A.M., F.O.), Cardioangiologisches Centrum Bethanien, Medical Department III am Markus Krankenhaus, Frankfurt (A.F., J.C.), Herz-Zentrum, Bad Krozingen (T.A.), and Technische Universität Dresden, Dresden (K.B.) - all in Germany; Hospital Clinic, University of Barcelona, Barcelona (J.B.); Isala Klinieken, Zwolle, the Netherlands (A.E.); London School of Hygiene and Tropical Medicine, London (S.J.P.); Clinique Pasteur, Toulouse, France (J.-P.A.); and Centro Cardiologico Monzino, University of Milan, Milan (C.T.).
authors.forename: Feifan
authors.initials: F
authors.lastname: Ouyang
authors.affiliation: From the Department of Cardiology, Asklepios Klinik St. Georg, Hamburg (K.-H.K., A.M., F.O.), Cardioangiologisches Centrum Bethanien, Medical Department III am Markus Krankenhaus, Frankfurt (A.F., J.C.), Herz-Zentrum, Bad Krozingen (T.A.), and Technische Universität Dresden, Dresden (K.B.) - all in Germany; Hospital Clinic, University of Barcelona, Barcelona (J.B.); Isala Klinieken, Zwolle, the Netherlands (A.E.); London School of Hygiene and Tropical Medicine, London (S.J.P.); Clinique Pasteur, Toulouse, France (J.-P.A.); and Centro Cardiologico Monzino, University of Milan, Milan (C.T.).
authors.forename: K R Julian
authors.initials: KR
authors.lastname: Chun
authors.affiliation: From the Department of Cardiology, Asklepios Klinik St. Georg, Hamburg (K.-H.K., A.M., F.O.), Cardioangiologisches Centrum Bethanien, Medical Department III am Markus Krankenhaus, Frankfurt (A.F., J.C.), Herz-Zentrum, Bad Krozingen (T.A.), and Technische Universität Dresden, Dresden (K.B.) - all in Germany; Hospital Clinic, University of Barcelona, Barcelona (J.B.); Isala Klinieken, Zwolle, the Netherlands (A.E.); London School of Hygiene and Tropical Medicine, London (S.J.P.); Clinique Pasteur, Toulouse, France (J.-P.A.); and Centro Cardiologico Monzino, University of Milan, Milan (C.T.).
authors.forename: Arif
authors.initials: A
authors.lastname: Elvan
authors.affiliation: From the Department of Cardiology, Asklepios Klinik St. Georg, Hamburg (K.-H.K., A.M., F.O.), Cardioangiologisches Centrum Bethanien, Medical Department III am Markus Krankenhaus, Frankfurt (A.F., J.C.), Herz-Zentrum, Bad Krozingen (T.A.), and Technische Universität Dresden, Dresden (K.B.) - all in Germany; Hospital Clinic, University of Barcelona, Barcelona (J.B.); Isala Klinieken, Zwolle, the Netherlands (A.E.); London School of Hygiene and Tropical Medicine, London (S.J.P.); Clinique Pasteur, Toulouse, France (J.-P.A.); and Centro Cardiologico Monzino, University of Milan, Milan (C.T.).
authors.forename: Thomas
authors.initials: T
authors.lastname: Arentz
authors.affiliation: From the Department of Cardiology, Asklepios Klinik St. Georg, Hamburg (K.-H.K., A.M., F.O.), Cardioangiologisches Centrum Bethanien, Medical Department III am Markus Krankenhaus, Frankfurt (A.F., J.C.), Herz-Zentrum, Bad Krozingen (T.A.), and Technische Universität Dresden, Dresden (K.B.) - all in Germany; Hospital Clinic, University of Barcelona, Barcelona (J.B.); Isala Klinieken, Zwolle, the Netherlands (A.E.); London School of Hygiene and Tropical Medicine, London (S.J.P.); Clinique Pasteur, Toulouse, France (J.-P.A.); and Centro Cardiologico Monzino, University of Milan, Milan (C.T.).
authors.forename: Kurt
authors.initials: K
authors.lastname: Bestehorn
authors.affiliation: From the Department of Cardiology, Asklepios Klinik St. Georg, Hamburg (K.-H.K., A.M., F.O.), Cardioangiologisches Centrum Bethanien, Medical Department III am Markus Krankenhaus, Frankfurt (A.F., J.C.), Herz-Zentrum, Bad Krozingen (T.A.), and Technische Universität Dresden, Dresden (K.B.) - all in Germany; Hospital Clinic, University of Barcelona, Barcelona (J.B.); Isala Klinieken, Zwolle, the Netherlands (A.E.); London School of Hygiene and Tropical Medicine, London (S.J.P.); Clinique Pasteur, Toulouse, France (J.-P.A.); and Centro Cardiologico Monzino, University of Milan, Milan (C.T.).
authors.forename: Stuart J
authors.initials: SJ
authors.lastname: Pocock
authors.affiliation: From the Department of Cardiology, Asklepios Klinik St. Georg, Hamburg (K.-H.K., A.M., F.O.), Cardioangiologisches Centrum Bethanien, Medical Department III am Markus Krankenhaus, Frankfurt (A.F., J.C.), Herz-Zentrum, Bad Krozingen (T.A.), and Technische Universität Dresden, Dresden (K.B.) - all in Germany; Hospital Clinic, University of Barcelona, Barcelona (J.B.); Isala Klinieken, Zwolle, the Netherlands (A.E.); London School of Hygiene and Tropical Medicine, London (S.J.P.); Clinique Pasteur, Toulouse, France (J.-P.A.); and Centro Cardiologico Monzino, University of Milan, Milan (C.T.).
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Albenque
authors.affiliation: From the Department of Cardiology, Asklepios Klinik St. Georg, Hamburg (K.-H.K., A.M., F.O.), Cardioangiologisches Centrum Bethanien, Medical Department III am Markus Krankenhaus, Frankfurt (A.F., J.C.), Herz-Zentrum, Bad Krozingen (T.A.), and Technische Universität Dresden, Dresden (K.B.) - all in Germany; Hospital Clinic, University of Barcelona, Barcelona (J.B.); Isala Klinieken, Zwolle, the Netherlands (A.E.); London School of Hygiene and Tropical Medicine, London (S.J.P.); Clinique Pasteur, Toulouse, France (J.-P.A.); and Centro Cardiologico Monzino, University of Milan, Milan (C.T.).
authors.forename: Claudio
authors.initials: C
authors.lastname: Tondo
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation / Q000295:instrumentation / Q000379:methods; D003452:Cryosurgery / Q000379:methods; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D012008:Recurrence; D012086:Reoperation; D016037:Single-Blind Method