title: First insights into cryoballoon-based pulmonary vein isolation taking the individual time-to-isolation into account.
abstract: OBJECTIVE
  Cryoballoon (CB)-based pulmonary vein isolation (PVI) is an established treatment for symptomatic atrial fibrillation (AF). In the present study, we sought to assess the efficacy and safety of CB-based PVI taking the individual time-to-isolation (TTI) into account.
  
  
  RESULTS
  Sixty consecutive patients with drug-refractory paroxysmal atrial fibrillation [n = 49 (82%)] or short-standing persistent atrial fibrillation [n = 11 (18%)] underwent ablation with a 28-mm second-generation CB. The TTI was assessed by spiral mapping-catheter recordings and subsequently followed by an additional freeze-time of 120 s. No bonus freeze-cycle was applied. If the TTI could not be assessed, a fixed freeze-cycle duration of 240 s was applied and successful PVI confirmed thereafter. Clinical follow-up (FU) included 12-lead ECGs and 24 h Holter-ECGs at 3, 6, and 12 months. A blanking period of 3 months was defined. A total of 239 pulmonary veins (PVs) were identified and successfully isolated. The mean TTI assessed in 170/239 (71%) PVs was 52 ± 32 s. The mean number of CB applications was 1.2 ± 0.5; mean freeze-cycle duration was 192 ± 41 s. Mean procedure and fluoroscopy times were 80 ± 24 min and 16 ± 7 min, respectively. Transient phrenic nerve palsy occurred in one patient (2%). During a mean FU of 405 ± 67 days, 43 patients (72%) remained in stable sinus rhythm.
  
  
  CONCLUSIONS
  Integrating an individual TTI protocol to CB-based PVI results in shorter freeze-cycle applications in a substantial portion of targeted PVs and an arrhythmia-free survival comparable to conventional ablation protocols. The complication rate is low.
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Bruno
authors.initials: B
authors.lastname: Reissmann
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Erik
authors.initials: E
authors.lastname: Wissner
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Deiss
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Heeger
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Schlueter
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Wohlmuth
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Christine
authors.initials: C
authors.lastname: Lemes
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Shibu
authors.initials: S
authors.lastname: Mathew
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Tilman
authors.initials: T
authors.lastname: Maurer
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Sohns
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Ardan
authors.initials: A
authors.lastname: Saguner
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Francesco
authors.initials: F
authors.lastname: Santoro
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Hayashi
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Riedl
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Feifan
authors.initials: F
authors.lastname: Ouyang
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Kuck
authors.affiliation: Department of Cardiology, Asklepios Klinik St. Georg, Lohmühlenstr. 5, 20099 Hamburg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Metzner
mesh_terms: D000200:Action Potentials; D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D062906:Cardiac Catheters; D017115:Catheter Ablation / Q000009:adverse effects / Q000295:instrumentation; D003452:Cryosurgery / Q000009:adverse effects / Q000295:instrumentation; D018572:Disease-Free Survival; D015716:Electrocardiography, Ambulatory; D005260:Female; D006339:Heart Rate; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology; D011667:Pulmonary Veins / Q000503:physiopathology / Q000601:surgery*; D015641:Radiography, Interventional; D012008:Recurrence; D012307:Risk Factors; D013997:Time Factors; D061665:Time-to-Treatment; D016896:Treatment Outcome
keywords: Ablation; Atrial fibrillation; Cryoballoon