Now Available: Final Rule for FDAAA 801 and NIH Policy on Clinical Trial Reporting

A Prospective Randomized Study Comparing Radiofrequency Energy With Cryoenergy (CRYO-RF)

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified October 2008 by Herz-Zentrums Bad Krozingen.
Recruitment status was:  Recruiting
CryoCath Technologies Inc.
Boston Scientific Corporation
Information provided by:
Herz-Zentrums Bad Krozingen Identifier:
First received: October 14, 2008
Last updated: NA
Last verified: October 2008
History: No changes posted

Transvenous pulmonary vein (PV) isolation using radiofrequency energy is an effective treatment for atrial fibrillation (1-4). However, rare but potentially life threatening complications such as thromboembolism (5), PV stenosis (5-10), left atrium-oesophageal fistula (11) and inflammatory syndromes (12) have been described. In preliminary studies an alternate approach using cryoenergy induces less endothelial disruption/ thrombus formation (13), preserves the extra cellular matrix and creates lesions with well-delineated border zones (14). Therefore, cryoenergy seems to be the ideal form of energy to safely perform PV isolation.

We therefore hypothesise that in the setting of PV isolation for the treatment of atrial fibrillation (AF) cryoenergy is less traumatic and therefore reduces systemic inflammatory responses compared to radiofrequency energy.

78 patients presenting with symptomatic intermittent or persistent AF will be randomised to PV isolation with either radiofrequency (26 patients open irrigated tip, 26 patients closed irrigated tip) or cryoenergy (26 patients with cryoballoon). Systemic markers of cell damage and inflammatory response (t-troponin, CK, CK-MB, vWF, PAI-1, micro particles, platelet activation/overall function, CRP, IL-6, IL-8, IL-10, TNF alpha, procalcitonin) will be monitored before, during and 48h after the procedure. Further endpoints include time to PV-isolation and procedure related complications. Six month clinical follow-up will focus on freedom from AF and cardiovascular events.

Condition Intervention Phase
Atrial Fibrillation Ablation
Procedure: PVI using an open irrigated tip catheter
Procedure: PVI using a closed irrigated tip catheter
Procedure: PVI using a cryoballoon
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Safety and Efficacy of Transvenous Pulmonary Isolation for the Treatment of Atrial Fibrillation: A Prospective Randomized Study Comparing Radiofrequency Energy With Cryoenergy

Resource links provided by NLM:

Further study details as provided by Herz-Zentrums Bad Krozingen:

Primary Outcome Measures:
  • Changes of platelet function (number of patients with an increase of more than 100% in platelets positive for either P-selectin or activated GP IIb/IIIa) [ Time Frame: before, at the end of intervention, 6, 24 and 48 hours later. ] [ Designated as safety issue: Yes ]

Secondary Outcome Measures:
  • Parameters of inflammation and tissue damage, the time to achieve PV-Isolation, freedom from AF. [ Time Frame: before, during and 6 months after procedure ] [ Designated as safety issue: Yes ]

Estimated Enrollment: 78
Study Start Date: July 2008
Estimated Study Completion Date: August 2009
Estimated Primary Completion Date: February 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: 1 Procedure: PVI using an open irrigated tip catheter
transseptal PVI using thermocooled ablation catheter (Biosense) with confirmation of conduction block
Active Comparator: 2 Procedure: PVI using a closed irrigated tip catheter
transseptal PVI using the CHILLI II catheter from BOSTON with confirmation of conduction block
Active Comparator: 3 Procedure: PVI using a cryoballoon
transseptal PVI using the cryoballoon from CRYOCATH


Ages Eligible for Study:   18 Years to 75 Years   (Adult, Senior)
Genders Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Age between 18 and 75 years
  • Symptomatic drug refractory (more than 2 antiarrhythmic drugs) paroxysmal or persistent AF
  • Documentation of AF on 12 lead ECG and/ or Holter
  • Left atrium of less than 55 mm
  • Informed consent signed by the patient

Exclusion Criteria:

  • Previous Ablation or operation for AF
  • Contra-indication for heart catheterisation
  • Cardioversion for AF during the 2 weeks before the procedure
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00773539

Bad Krozingen, Germany, 79189
Sponsors and Collaborators
Herz-Zentrums Bad Krozingen
CryoCath Technologies Inc.
Boston Scientific Corporation
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Thomas Arentz, Herz-Zentrum Bad Krozingen Identifier: NCT00773539     History of Changes
Other Study ID Numbers: CRYO-BAD-KROZ 
Study First Received: October 14, 2008
Last Updated: October 14, 2008
Health Authority: Germany: Federal Institute for Drugs and Medical Devices

Keywords provided by Herz-Zentrums Bad Krozingen:
atrial fibrillation
pulmonary veins

Additional relevant MeSH terms:
Atrial Fibrillation
Arrhythmias, Cardiac
Heart Diseases
Cardiovascular Diseases
Pathologic Processes processed this record on January 18, 2017