Cryoenergy Or Radiofrequency for Pulmonary Vein Isolation

Atrial Fibrillation Clinical Trial

— COR  

Official title:

Cryoenergy Or Radiofrequency for Pulmonary Vein Isolation (COR Trial)

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00969735
• Other study ID #: COR-1
• Status: Completed
• Phase: Phase 4
• First received: August 28, 2009
• Last updated: April 1, 2013
• Start date: July 2009
• Est. completion date: May 2012

Study information

• Verified date: April 2013
• Source: Hospital San Carlos, Madrid
• Contact: n/a
• Is FDA regulated: No
• Health authority: Spain: Ministry of Health
• Study type: Interventional

Clinical Trial Summary

This is a prospective single-center randomized trial comparing the efficacy and safety of PV cryoablation with the Arctic Front® catheter versus the standard PV isolation using radiofrequency irrigated tip catheters. The efficacy of both strategies will be evaluated from a clinical point of view and from the detection and quantification of AF episodes by means of the Reveal XT® implantable loop recorder.

Description:

Pulmonary vein (PV) isolation using a radiofrequency catheter is the most widespread technique for atrial fibrillation (AF) ablation. These procedures are difficult and time-consuming, because they require precise catheter manipulation and multiple radiofrequency applications. Thus, alternative techniques are being investigated to simplify the procedure. Recently, a cryoenergy balloon catheter has been developed for PV isolation (Arctic Front®, Cryocath Technologies). When this catheter is deployed at the PV antrum, it can create a circumferential lesion around the PV ostium by delivering a single cryoenergy application.

An implantable loop recorder for AF detection has been made available (Reveal XT®, Medtronic). It may help taking clinical decisions regarding anticoagulant and antiarrhythmic therapy and, at the same time, it may be a powerful tool to evaluate the efficacy of different therapeutic strategies.

This is a prospective single-center randomized trial comparing the efficacy and safety of PV cryoablation with the Arctic Front® catheter vs. the standard PV isolation using radiofrequency irrigated tip catheters. The efficacy of both strategies will be evaluated from a clinical point of view and from the detection and quantification of AF episodes by means of the Reveal XT® implantable loop recorder.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 50
• Est. completion date: May 2012
• Est. primary completion date: May 2012
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years to 75 Years

Eligibility

Inclusion Criteria:

• Symptomatic recurrent paroxysmal AF (>2 episodes in the last 6 months), and

• Refractory to one or more class I or III antiarrhythmic drugs, and

• PV anatomy consisting of 4 single PV, with the long diameter of the right superior PV ostium = 20 mm.

Exclusion Criteria:

• Age: < 18 or > 75 year-old

• Prior AF ablation

• Pregnancy

• Concomitant acute illness

• Hyperthyroidism

• Moderate to severe valvular heart disease

• Prior cardiac surgery

• Left atrium > 50 mm (anteroposterior diameter, parasternal long-axis view)

• Intracardiac thrombus

• Contraindications for anticoagulant therapy

• Inability to be followed in our center for at least 1 year

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Atrial Fibrillation

Intervention

Device:
• Pulmonary vein cryoablation
A deflectable over-the-wire cryoablation balloon catheter (Arctic Front®) will be inflated and be positioned at each PV antrum. Then, cryoenergy will be delivered for 300 seconds. During cryoablation of the right PVs, the right phrenic nerve integrity will be monitored by the observation of right hemi-diaphragm contractions in response to right phrenic nerve pacing at the superior vena cava. Once the 4 PVs are cryoablated, the Arctic Front® catheter will be replaced by a decapolar PV mapping circular catheter (Lasso®, Biosense Webster, Diamond Bar, California, EEUU) to evaluate PV conduction. A second cryoablation application may be delivered at each PV, if necessary. Crossover to RF ablation to complete PV isolation is discouraged.
• Pulmonary vein radiofrequency ablation
Ablation approach is ostial electrical isolation of all PVs with simultaneous use of the CARTO® electroanatomic mapping system (Biosense Webster, Tirat-Ha-Carmel, Israel). PV isolation will be performed by delivering RF energy at ostial sites with earliest PV potentials. Flow rate during the RF applications will be set at 15 mL/min (baseline 2 mL/min). Temperature and power limits will be set at 45ºC and 35 W. It will be allowed a 5 W reduction in power limit setting for small PVs (angiographic supero-inferior diameter > 12 mm), and a 5 W increase in areas located away from the esophagus, and for focal applications at sites resistant to ablation or recurrent gaps. The end-point of ablation will be to achieve bidirectional PV conduction block.

Locations

Country	Name	City	State
Spain	Unidad de Arritmias, Hospital Clínico San Carlos	Madrid

Sponsors (2)

Lead Sponsor	Collaborator
Hospital San Carlos, Madrid	Spanish Society of Cardiology

Country where clinical trial is conducted

Spain, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Proportion of patients without AF recurrences longer than 2 minutes		At the 12th month from ablation (using a blanking period of 3 months following ablation)	No
Secondary	Time to first AF recurrence longer than 2 minutes		Within the first 12 months from ablation (using a blanking period of 3 months following ablation, and without the use of any blanking period)	No
Secondary	Cumulative burden of AF (number of AF episodes longer than 2 minutes)		At the 12th month from ablation (using a blanking period of 3 months following ablation)	No
Secondary	Cumulative burden of AF (percentage of time in AF)		At the 12th month from ablation (using a blanking period of 3 months following ablation)	No
Secondary	Proportion of patients with episodes of regular atrial tachycardia or atrial flutter requiring treatment with drugs, electrical cardioversion or ablation.		Within the first 12 months from ablation	No
Secondary	Quality of Life and symptom status		At the 12th month from ablation	No
Secondary	Proportion of patients with procedure-related complications		Within the first 12 months from ablation	Yes
Secondary	Procedure time (minutes elapsed from the first puncture of the femoral vein to the removal of the last catheter)		At the end of the ablation procedure	No
Secondary	Ablation time (minutes elapsed from the onset of the first energy delivery to the end of the last energy delivery).		At the end of the ablation procedure	No
Secondary	Fluoroscopy time (minutes of fluoroscopy used during the entire ablation procedure)		At the end of the ablation procedure	No
Secondary	Proportion of pulmonary veins remaining isolated		At the end of the ablation procedure	No