Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12606000467538
Ethics application status
Approved
Date submitted
30/07/2006
Date registered
9/11/2006
Date last updated
11/01/2011
Type of registration
Retrospectively registered

Titles & IDs
Public title
Circumvenous ablation for atrial fibrillation
Scientific title
The Safety and Efficacy of Circumvenous Ablation for Reducing the Recurrence of Atrial Fibrillation and Flutter
Secondary ID [1] 253389 0
Comparison of Posterior Left Atrial (Box) Isolation and Wide Antral Isolation for Atrial Fibrillation
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Atrial fibrillation 1444 0
Condition category
Condition code
Cardiovascular 1539 1539 0 0
Other cardiovascular diseases

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The two procedures being compared in this trial, namely circumvenous pulmonary vein isolation and conventional pulmonary vein isolation (which is the control group) are largely similar except for the pattern of ablation lesions deployed in the left atrium. Circumvenous ablation lesions will be deployed as a large ring that encircles all four pulmonary veins, whereas conventional ablation will be as two rings that encircle ipsilateral pulmonary veins. These procedures will be performed under general anaesthesia or intravenous sedation with midazolam and fentanyl. Three long sheaths will be inserted via the right femoral vein. An SL3 Daig sheath (St Jude Medical, St Paul, MN) will be used to place a decapolar catheter in the coronary sinus. The other two sheaths (Preface, Cordis-Webster, Diamond Bar, CA and Agilis Steerable Introducer (St Jude Medical, St Paul, MN) will be passed into the left atrium via transeptal punctures and used to introduce a circular decapolar catheter (Lasso, Cordis-Webster, Diamond Bar, CA) and an open irrigated 5mm tip ablation catheter (Thermocool, Cordis-Webster, Diamond Bar, CA) respectively. Fluoroscopy and an electroanatomical mapping system (CARTO, Biosense Webster, Diamond Bar, CA) will be used to guide the manipulation of the ablation catheter. After the pulmonary veins have been identified using contrast cineradiography and by observing the movement of the catheters in the left atrium, patients will be randomized to have one of the two patterns of lesions made using radiofrequency ablation. The endpoint for both techniques will be electrical isolation of all the pulmonary veins. Patients will also be randomised to receive linear ablations across the left mitral isthmus. A tricuspid annulus- inferior vena cava isthmus ablation will be performed on all patients. Both types of ablation procedure will usually take between three to five hours to complete. Patients will then be followed up for one year post procedure.
Intervention code [1] 1235 0
Treatment: Other
Comparator / control treatment
Conventional pulmonary vein isolation.
Control group
Active

Outcomes
Primary outcome [1] 2123 0
Recurrence of atrial fibrillation
Timepoint [1] 2123 0
1 year
Primary outcome [2] 2124 0
Recurrence of atrial flutter
Timepoint [2] 2124 0
2 year
Primary outcome [3] 2125 0
Ongoing requirement of antiarrhythmic drug therapy
Timepoint [3] 2125 0
3 year
Secondary outcome [1] 3670 0
Procedure duration
Timepoint [1] 3670 0
At time of procedure
Secondary outcome [2] 3671 0
Procedure radiation exposure
Timepoint [2] 3671 0
At time of procedure
Secondary outcome [3] 3672 0
Termination of atrial fibrillation during procedure
Timepoint [3] 3672 0
At time of procedure
Secondary outcome [4] 3673 0
Documented recurrence of atrial arrhythmias prior to discharge
Timepoint [4] 3673 0
At time of discharge following procedure
Secondary outcome [5] 3674 0
Procedural complications
Timepoint [5] 3674 0
At time of discharge following procedure
Secondary outcome [6] 3675 0
Duration of hospital stay
Timepoint [6] 3675 0
At time of discharge following procedure
Secondary outcome [7] 3676 0
Left atrial function measured by a variety of echocardiographic indices
Timepoint [7] 3676 0
Enrolment, 2 and 6 months
Secondary outcome [8] 3677 0
Atrial fibrillation and atrial flutter recurrence within three months
Timepoint [8] 3677 0
3 months
Secondary outcome [9] 3678 0
Atrial fibrillation, atrial flutter between 3 and 6 months
Timepoint [9] 3678 0
Between 3 and 6 months
Secondary outcome [10] 3679 0
Requirement of antiarrhythmic medications
Timepoint [10] 3679 0
Between 3 and 6 months
Secondary outcome [11] 3680 0
Arrhythmia on 7-day Holter monitoring
Timepoint [11] 3680 0
Between 3 and 6 months
Secondary outcome [12] 3681 0
Exercise capacity
Timepoint [12] 3681 0
Enrolment and 6 months
Secondary outcome [13] 3682 0
Quality of life (SF-36v2)
Timepoint [13] 3682 0
Enrolment and 6 months

Eligibility
Key inclusion criteria
1. Symptomatic atrial fibrillation refractory to medical therapy2. Ability to provide informed consent.
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
1. Previous percutaneous or operative procedure for atrial fibrillation involving linear or encircling lesions.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation concealment will be by sealed opaque envelopes.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Software generate permuted block randomisation will be used with a random block size.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Factorial
Other design features
Phase
Phase 2 / Phase 3
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
1/10/2006
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
220
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 1679 0
Hospital
Name [1] 1679 0
Westmead Hospital
Country [1] 1679 0
Australia
Funding source category [2] 3368 0
Government body
Name [2] 3368 0
NHMRC
Country [2] 3368 0
Australia
Primary sponsor type
Individual
Name
Stuart P Thomas
Address
Department of Cardiology
Westmead Hospital
Corner Hawkesbury and Darcy Roads
Westmead NSW 2145
Country
Australia
Secondary sponsor category [1] 1480 0
Individual
Name [1] 1480 0
David L Ross
Address [1] 1480 0
Department of Cardiology
Westmead Hospital
Corner Hawkesbury and Darcy Roads
Westmead NSW 2145
Country [1] 1480 0
Australia
Secondary sponsor category [2] 1481 0
Individual
Name [2] 1481 0
Toon Wei Lim
Address [2] 1481 0
Department of Cardiology
Westmead Hospital
Corner Hawkesbury and Darcy Roads
Westmead NSW 2145
Country [2] 1481 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 3124 0
Westmead Hospital Ethics Committee-Westmead Hospital
Ethics committee address [1] 3124 0
Westmead Hospital, Sydney
Ethics committee country [1] 3124 0
Australia
Date submitted for ethics approval [1] 3124 0
Approval date [1] 3124 0
10/07/2006
Ethics approval number [1] 3124 0
2006/6/4.10(2373)
Ethics committee name [2] 3125 0
Westmead Hospital Ethics Committee-Westmead Private Hospital
Ethics committee address [2] 3125 0
Westmead Private Hospital, Sydney
Ethics committee country [2] 3125 0
Australia
Date submitted for ethics approval [2] 3125 0
Approval date [2] 3125 0
12/09/2006
Ethics approval number [2] 3125 0
2006/6/4.10(2373)

Summary
Brief summary
Atrial fibrillation is the commonest heart rhythm disturbance in humans. It is associated with an increased risk of death and serious illnesses like stroke and heart failure. Drug therapy alone has limited effectiveness in some patients who remain in atrial fibrillation and they may be highly symptomatic despite maximal treatment. Recently, it has been possible to cure atrial fibrillation in many patients by creating ablation lesions in the heart using flexible plastic coated wire catheters to deliver electrical energy. This is done by passing these catheters via veins in the leg into the left upper chamber of the heart, the left atrium. This is a rapidly evolving technique and it is not clear what pattern of ablation lesions is most effective. Moreover, it is a time consuming procedure with significant serious complications and a small risk of death and this has limited its application. The aim of this project is to compare two different patterns of ablation in terms of safety and efficacy. The patients in this study will be randomly assigned to one of two groups. One group of patients will undergo circumvenous ablation consists of a single ring that encircles all the pulmonary veins which carry blood from the lungs back to the left atrium. The other group will have their veins isolated in pairs on each side. Patients in each group will also be randomised to receive ablation of the mitral isthmus. Both groups will then be followed up for a year to determine if either pattern is superior in terms of recurrence rates, complication rates, exercise capacity and quality of life. Both procedures will also be compared in terms of procedure time and radiation exposure. Atrial fibrillation is responsible for a considerable burden of illness and death on the community and any improvements in ablation techniques for its treatment can have a major impact on the quality of life for a significant number of people.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 35164 0
Address 35164 0
Country 35164 0
Phone 35164 0
Fax 35164 0
Email 35164 0
Contact person for public queries
Name 10424 0
Toon Wei Lim
Address 10424 0
Department of Cardiology
Westmead Hospital
Westmead NSW 2145
Country 10424 0
Australia
Phone 10424 0
+61 2 98456795
Fax 10424 0
+61 2 98458323
Email 10424 0
[email protected]
Contact person for scientific queries
Name 1352 0
Stuart P Thomas
Address 1352 0
Department of Cardiology
Westmead Hospital
Westmead NSW 2145
Country 1352 0
Australia
Phone 1352 0
+61 2 98456795
Fax 1352 0
+61 2 98458323
Email 1352 0
[email protected]

No information has been provided regarding IPD availability


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
SourceTitleYear of PublicationDOI
EmbaseAtrial Ectopy Predicts Late Recurrence of Atrial Fibrillation after Pulmonary Vein Isolation.2015https://dx.doi.org/10.1161/CIRCEP.114.002052
EmbaseClinical significance of early atrial arrhythmia type and timing after single ring isolation of the pulmonary veins.2015https://dx.doi.org/10.1093/europace/euu314
EmbasePosterior left atrial isolation for atrial fibrillation in left ventricular diastolic impairment is associated with better arrhythmia free survival.2015https://dx.doi.org/10.1016/j.ijcard.2015.01.068
N.B. These documents automatically identified may not have been verified by the study sponsor.