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FREEZE Cohort Study

This study is ongoing, but not recruiting participants.
Information provided by (Responsible Party):
Stiftung Institut fuer Herzinfarktforschung Identifier:
First received: May 13, 2011
Last updated: June 16, 2016
Last verified: June 2016

May 13, 2011
June 16, 2016
April 2011
January 2016   (Final data collection date for primary outcome measure)
AF recurrency rate (any detected episode lasting > 30 sec) at 12 months follow up [ Time Frame: Admission to hospital until 12 months thereafter ]
Same as current
Complete list of historical versions of study NCT01360008 on Archive Site
  • Comparison of complication rates (any complications and major complications) at 12 months follow-up [ Time Frame: Admission to hospital until 12 months thereafter ]
  • Specific complication aspects with respect to phrenic nerve palsy and PV stenosis [ Time Frame: Admission to Hospital until 12 months thereafter ]
  • Efficacy (AF recurrency rates), safety (complication rates), and procedural parameters in cryoballoon or RF ablation as means for assessing advantages of preprocedural CT or MRI scan performing 3 D anatomy of the left atrium and pulmonary veins [ Time Frame: Admission to Hospital until 12 months thereafter ]
  • Persistent AF: Impact on efficacy analyzing procedural aspects in cryoballoon PVI [ Time Frame: Admission to Hospital until 12 months thereafter ]
  • Real-time ECG-monitoring of PV-isolation during freezing: Does the microcircular mapping catheter add significant benefit to the cryoballoon procedure [ Time Frame: Admission to Hospital until 12 months thereafter ]
Same as current
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Not Provided
FREEZE Cohort Study
FREEZE Cohort Study
Safety and efficacy in radiofrequency (RF) or cryoballoon atrial fibrillation (AF) ablation will be investigated in a cohort study design in experienced electrophysiologic (EP) centers analyzing propensity-matched cohorts.
Prior to participation in the cohort-study each EP center had to perform a minimum of 50 RF or 50 cryoballoon approaches. To insure the consecutiveness of recruitment, participating centers have to announce the intention to ablate the patient prior to the procedure to the coordinating center in Ludwigshafen. After inclusion of 500 patients with well accepted criteria for AF ablation undergoing cryoballoon pulmonary vein isolation (PVI) in experienced german EP centers inclusion of patients will be extended to european centers. A total of 4.000 patients will be included in the cohort-study, 2.000 in both the cryoballoon and the RF arm.
Observational Model: Cohort
Time Perspective: Prospective
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Not Provided
Non-Probability Sample
Patients with AF ablation targeting
Not Provided
  • Cryo ablation
    Patients with first Ablation of atrial fibrillation treated by cryo ablation
  • RF ablation
    Patients with first Ablation of atrial fibrillation treated by Radio frequency ablation

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Active, not recruiting
April 2017
January 2016   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • Documented paroxysmal AF (2 episodes of PAF within the last 3 months) or Persistent AF (lasting < 1 year)
  • First ablation of AF
  • Age ≥18 years
  • Documented inefficacy of at least 1 AAD not including β-blockers
  • Written informed consent

Exclusion Criteria:

  • Longstanding persistent AF lasting > 1 year
  • Acute coronary syndrome (ACS)
  • Heart failure NYHA IV
  • Thrombocytosis, thrombocytopenia
  • Any condition contraindicating chronic anticoagulation
  • Stroke or TIA within 6 months prior to ablation
  • Uncontrolled hyperthyroidism
  • Pregnancy
  • Life expectancy < 1 year
Sexes Eligible for Study: All
18 Years and older   (Adult, Senior)
Contact information is only displayed when the study is recruiting subjects
United States,   Austria,   Germany,   Greece,   South Africa,   Spain
Not Provided
De-identified patient data will be published after end of follow up period
Stiftung Institut fuer Herzinfarktforschung
Stiftung Institut fuer Herzinfarktforschung
Principal Investigator: Ellen Hoffmann, MD Klinikum Bogenhausen, München
Stiftung Institut fuer Herzinfarktforschung
June 2016

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP