Cryoablation of atrial flutter

ISRCTN	ISRCTN46168176
DOI	https://doi.org/10.1186/ISRCTN46168176
Secondary identifying numbers	N/A

Submission date: 23/03/2012
Registration date: 03/04/2012
Last edited: 18/09/2014

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Circulatory System

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English summary of protocol

Background and study aims
Atrial flutter is an abnormality in the beating of the heart, also known as arrhythmias. This arrhythmia can be the cause of stroke, heart failure and eventually death. This heart condition is successfully treatable today with catheter ablation, which destroys a small area of heart tissue that is causing rapid and irregular heartbeats. The aim of this study was to compare two commonly used catheter ablation technologies, namely radiofrequency (burning of the tissue), which is the standard treatment, and cryoablation (freezing of the tissue), which is the alternative treatment.

Who can participate?
All patients regardless of age and gender with clear atrial flutter symptoms can participate in this study.

What does the study involve?
In order to evaluate heart function, patients undergo a clinical examination, ECG recording and echocardiography. Patients will then be randomly allocated to be treated with either radiofrequency or cryoablation. Six months after treatment all patients will be followed up with an out-patient visit and an ECG recording.

What are the possible benefits and risks of participating?
The possible benefits of participating are that cryoablation is practically painless and equally effective to standard treatment (radiofrequency). No risks have been shown in the clinical studies published so far.

Where is the study run from?
The study is run from Karolinska University Hospital, Stockholm, Sweden.

When is the study starting and how long is it expected to run for?
The study ran from January 2007 to November 2010.

Who is funding the study?
Financial support was provided through the regional agreement on medical training and clinical research (ALF) between Stockholm County Council and the Karolinska Institute (Sweden).

Who is the main contact?
Dr Hamid Bastani
Karolinska University Hospital, Stockholm, Sweden

Contact information

Prof Mats Jensen-Urstad
Scientific

Department of Cardiology
Karolinska Institute
Karolinska University Hospital
Stockholm
14186
Sweden

Email	mats.jensen-urstad@karolinska.se

Study information

Study design	Prospective single-blinded randomized controlled single-centre trial
Primary study design	Interventional
Secondary study design	Randomised controlled trial
Study setting(s)	Hospital
Study type	Treatment
Participant information sheet	Not available in web format, please use the contact details below to request a patient information sheet
Scientific title	Cryothermal versus Radiofrequency Ablation as atrial Flutter Therapy: a randomized comparison
Study acronym	CRAFT
Study objectives	Catheter ablation with cryothermal energy is non-inferior to ablation with radiofrequency energy for the treatment of cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL)
Ethics approval(s)	Regional Ethical Review Board, Stockholm, 2006, ref: 1006-31
Health condition(s) or problem(s) studied	Atrial flutter
Intervention	Cryo group: Cryo was delivered with the use of a steerable 9F, 8-mm-tip catheter (Freezor MAX, CryoCath, Quebec, Canada), which was positioned on the TV annulus. Cryoablation was then performed using a sequential application technique point-by-point from the TV annulus to the inferior vena cava (IVC). RF group: RF was performed using a 7F 3.5-mm open-irrigated-tip catheter (Biosense-Webster Inc., Diamond Bar, CA. USA) to create an ablation line between the tricuspid valve and the IVC.
Intervention type	Other
Primary outcome measure	Clinical success defined as the freedom from atrial flutter evaluated at the 6-month follow-up.
Secondary outcome measures	1. Acute ablation success defined as bidirectional CTI-block safety assessed by the rate of periprocedural complications, procedure and fluoroscopy times and the level of pain experienced by the patient during the ablation procedure 2. To compare the utility of non-fluoroscopic mapping systems (Ensite NavX) with conventional mapping all patients were also randomized to either fluoroscopy only or Ensite NavX and fluoroscopy
Overall study start date	01/01/2007
Completion date	30/11/2010

Eligibility

Participant type(s)	Patient
Age group	Adult
Lower age limit	18 Years
Sex	Both
Target number of participants	150
Key inclusion criteria	1. Consecutive patients referred to our institution for ablation therapy of ECG-documented typical CTI-dependent AFL 2. Patients above the age of 18 with symptomatic CTI-dependent AFL documented on a 12-lead ECG with typical ECG appearance of negative saw tooth waves in the inferior limb leads and positive deflections in V1 or positive saw tooth waves in the inferior limb leads and negative deflections in V1 3. Patients with a history of atrial fibrillation included if they had predominant atrial flutter under chronic treatment with class I or III antiarrhythmic agents
Key exclusion criteria	1. Prior ablation for AFL 2. Atrial flutter related to recently undergone surgery, hyperthyroidism or other severe disease 3. Inability to adhere to the study protocol 4. Pregnancy 5. Predominant atrial fibrillation 6. Contraindication to warfarin
Date of first enrolment	01/01/2007
Date of final enrolment	30/11/2010

Locations

Countries of recruitment

Sweden

Study participating centre

Department of Cardiology

Stockholm
14186
Sweden

Sponsor information

Karolinska University Hospital (Sweden)
University/education

Department of Cardiology
Stockholm
141 86
Sweden

Phone	+46 8 585 800 00
Email	mats.jensen-urstad@karolinska.se
Website	http://www.karolinska.se/en/
"ROR"	https://ror.org/00m8d6786

Funders

Funder type

Government

Stockholm County Council (Sweden)
Government organisation / Local government

Alternative name(s): Stockholm County Council
Location: Sweden

Karolinska Institute (Sweden)

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not provided at time of registration
Publication and dissemination plan	Not provided at time of registration
IPD sharing plan