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Surgical or Catheter Ablation of Lone Atrial Fibrillation (AF) Patients (SCALAF)

This study has been terminated.
(Enrollments slowed down significantly, despite several attempts to re-launch.)
ClinicalTrials.gov Identifier:
First Posted: June 23, 2008
Last Update Posted: May 16, 2017
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Information provided by (Responsible Party):
Medtronic Cardiovascular ( Medtronic Bakken Research Center )
Prospective randomized interventional trial comparing the efficacy of circumferential pulmonary vein ostia ablation using surgical versus catheter techniques in the treatment of paroxysmal atrial fibrillation. Success rate determined by REVEAL-XT (AF implantable monitoring device).

Condition Intervention
Atrial Fibrillation Procedure: Catheter Ablation Procedure: Surgical Ablation

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Surgical or Catheter Ablations in Patients With Lone Atrial Fibrillation: Determination of Acute and Long Term Success Rate (SCALAF Success Trial)

Resource links provided by NLM:

Further study details as provided by Medtronic Cardiovascular ( Medtronic Bakken Research Center ):

Primary Outcome Measures:
  • Change in AF Burden After Ablation Therapy Measured With REVEAL-XT Implantable Device. [ Time Frame: Baseline through 3-6 months post-ablation ]
    AF Burden is defined as the percentage of time during the follow-up period that a subject is in AF, as measured by the REVEAL-XT implantable device.

Secondary Outcome Measures:
  • Treatment Failures Requiring Redo or Alternative Therapy [ Time Frame: Time from procedure until 6 months post-ablation ]
  • Number of Subjects With Adverse Events, Associated With the Ablation Procedure [ Time Frame: Time from procedure ]
  • Mortality and Hospitalization [ Time Frame: Time from procedure until 24 months post-ablation ]
  • Duration, Burden and Costs of Treatment Procedures [ Time Frame: Through 24 months post- ablation ]
  • Reduced Number, Duration and Severity of AF Symptoms [ Time Frame: Through 24 months post-ablation ]
  • Symptoms Associated With Atrial Arrhythmias [ Time Frame: Through 24 months post-ablation ]
  • Occurences of Treatment of Arrhythmic Episodes [ Time Frame: Through 24 months post-ablation ]
  • Assessment of AF Burden [ Time Frame: Through 24 months post-ablation ]
  • Reduced Anti-arrhythmic Drug Requirement [ Time Frame: Through 24 months post-ablation ]
  • Left Atrial Dimension and Contractility [ Time Frame: Through 24 months post-ablation ]

Enrollment: 80
Study Start Date: November 2007
Study Completion Date: November 2016
Primary Completion Date: August 2015 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: 1
Arm 1: Catheter Ablation
Procedure: Catheter Ablation
Patients undergoing left atrial circumferential pulmonary vein ostia ablation.
Active Comparator: 2
Arm 2: Surgical Ablation.
Procedure: Surgical Ablation
patients undergoing left atrial circumferential pulmonary vein ostia ablation via minimal invasive surgery.

  Hide Detailed Description

Detailed Description:

Title: Surgical or Catheter Ablation in patients with Lone Atrial Fibrillation: determination of acute and long term SUCCESS (SCALAF-success trial).

Background: Anti-arrhythmic drugs are used in daily practice to treat patients with paroxysmal idiopatic AF. Often the origin of the AF can be found in the muscle sleeves running up the pulmonary veins. Drug treatment is not always successful and prone to evoke negative side effects. The surgical MAZE procedure was applied in the past, but this is a time consuming, cumbersome technique, often associated with significant complications. Cardiac radio-frequency ablation offers an alternative, easy and less time consuming treatment: lesions prevent normal electrical wave front propagation and might stop the continuation of atrial fibrillation wave fronts. Ablation can be implemented by use of special catheters inserted via the groin or using the Medtronic Cardioblate® Surgical Ablation System applied via minimal invasive surgical techniques.

Purpose: Compare the effectiveness of pulmonary vein isolation achieved via catheter or via surgical ablation techniques to treat patients with paroxysmal lone AF.

Study design: A prospective, randomized multi-center interventional study.

Patients: Patients suffering from paroxysmal idiopatic AF (no associated or underlying structural heart disease) complying with following inclusion criteria:

  • minimally one documented AF-episode in the last 6 months;
  • refractory to at least 2 class I or III anti-arrhythmic drugs;
  • age > 18 year

Intervention: Patients are randomized to either the surgical or the catheter ablation group and receive the indicated treatment. During the critical assessment period, the patients are weaned from anti-arrhythmic medication.

Primary endpoint: Reduction in AF occurrence measured by the AF-burden parameter in the critical period between 3 and 6 months post-ablation. AF burden is measured automatically by means of the Reveal XT, implanted at study enrolment to document the baseline characteristics.

Secondary endpoints:

  • Failure of therapy requiring re-interventions;
  • Duration, burden and costs of ablation procedures:
  • Reduction in frequency, duration and level of severity of AF symptoms;
  • Occurences of treatments of arrythmic episodes;
  • Assessment of AF burden during follow-up period
  • Symptoms associated with AF;
  • Reduced necessity of anti-arrhythmic or anticoagulant medication;
  • Left atrial dimensions and contractility
  • Adverse events associated with the ablation therapy;
  • Occurrence of other clinical adverse events (TIA, CVA, bleeds, tamponade, MI) at 3, 6, 12 and 24 months of follow up
  • Mortality and hospitalisation

Risk assessment: Possible side effects : irregular heart rhythm, pericardial fluid, stroke, heart infarct, disturbances of the conduction system in the heart, local pain at the site of incisions, heart failure or reduced pump function of the heart.

Possible benefits: Regulation of the heart rhythm without applying MAZE procedure or opening of the thorax. Reduction or relief from symptoms associated with AF. Partial or complete reduction of anti-arrhythmic medication. Control of anti-coagulant medication. Improved quality of life for the patients.

Visits are planned at study entrance and Reveal XT implant (assessment at baseline, application of the ablation therapy), discharge from hospital, and at 3, 6, 12 and 24 months post-ablation.


Information from the National Library of Medicine

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, Learn About Clinical Studies.

Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Patient has documented Paroxysmal AF as defined by the ACC/AHA/ESC guidelines
  • Minimal one documented AF episode in the last 6 months
  • Refractory to minimal two Class I or III anti-arrhythmic drug
  • Age > 18 years
  • Signed and dated the Patient Informed Consent.
  • Patient can tolerate anti-coagulation therapy (Warfarin/Coumadin)

Exclusion Criteria:

  • Patient has a structural heart disease
  • Ejection fraction < 40 %
  • Echocardiographic evidence for a left atrium > 45 mm (parasternal axis)
  • Patients on amiodarone, or patients known to be intolerant for amiodarone
  • Dextrocardia, current endocarditis, systemic infection, renal failure
  • Patient has known cerebrovascular disease, including a history of stroke, CVA or TIA
  • Pregnancy at enrolment; or planned pregnancy within the follow up period
  • Patient has a life expectancy less than 1 year
  • The subject is participating in another device or drug study
  • The patient is unable and/or unwilling to cooperate with study procedures or required follow up visits
  • Echocardiographic (TTE) evidence for presence of left atrial thrombus
  • Previous (cardio-) thoracic surgery
  • Previous left atrial ablation
  • Patients with permanent or persistent AF
  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00703157

Isala Klinieken
Zwolle, Netherlands, 8011 JW
Sponsors and Collaborators
Medtronic Bakken Research Center
Principal Investigator: Hauw Sie, MD Isala Klinieken, Zwolle
  More Information

Responsible Party: Medtronic Bakken Research Center
ClinicalTrials.gov Identifier: NCT00703157     History of Changes
Other Study ID Numbers: BRC-CS
First Submitted: June 19, 2008
First Posted: June 23, 2008
Results First Submitted: March 22, 2017
Results First Posted: May 16, 2017
Last Update Posted: May 16, 2017
Last Verified: May 2017
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Plan Description: There is no plan or intention to share individual participant data (IPD)

Additional relevant MeSH terms:
Atrial Fibrillation
Arrhythmias, Cardiac
Heart Diseases
Cardiovascular Diseases
Pathologic Processes