Cryoballoon vs. Irrigated Radiofrequency Catheter Ablation: Double Short vs. Standard Exposure Duration (CIRCA-DOSE)
Paroxysmal Atrial Fibrillation
About this trial
This is an interventional treatment trial for Paroxysmal Atrial Fibrillation
Eligibility Criteria
Inclusion Criteria:
- Non-permanent atrial fibrillation documented on a 12 lead ECG, TTM or Holter monitor within the last 12 months Low Burden Paroxysmal - ≥2 episodes of AF over the past 12 months; Episodes terminate spontaneously within 7 days or via cardioversion within 48 hours of onset.
High Burden Paroxysmal - ≥4 episodes of AF over the past 6 months, with ≥2 episodes >6 hours in duration; Episodes terminate spontaneously within 7 days or via cardioversion within 48 hours of onset.
Early Persistent - ≥2 episodes of AF over the past 12 months; Episodes are successfully terminated via cardioversion within 7 days of onset.
- Age of 18 years or older on the date of consent
- Candidate for ablation based on AF that is symptomatic and refractory (ineffective or intolerant) to at least one class 1 or 3 antiarrhythmic
- Continuous anticoagulation with warfarin (INR 2-3), low molecular weight heparin, or a novel oral antithrombotic (dabigatran, apixaban, rivaroxaban) for ≥4 weeks prior to the ablation; or a TEE that excludes LA thrombus ≤48 hours before ablation
- Informed Consent Form
Exclusion Criteria:
- Previous left atrial (LA) ablation or LA surgery
- Pre-existing pulmonary vein stenosis or PV stent
- Pre-existing hemidiaphragmatic paralysis
- Contraindication to anticoagulation or radiocontrast materials
- Anteroposterior LA diameter greater than 5.5 cm by TTE
- Cardiac valve prosthesis
- Clinically significant (moderately-severe, or severe) mitral valve regurgitation or stenosis
- Myocardial infarction, PCI / PTCA, or coronary artery stenting during the 3-month period preceding the consent date
- Cardiac surgery during the three-month interval preceding the consent date
- Significant congenital heart defect (including atrial septal defects or PV abnormalities but not including PFO)
- NYHA class III or IV congestive heart failure
- Left ventricular ejection fraction (LVEF) less than 35%
- Hypertrophic cardiomyopathy
- Significant CKD (eGFR <30 mL/min/m2)
- Uncontrolled hyperthyroidism
- Cerebral ischemic event (strokes or TIAs) during the six-month interval preceding the consent date
- Subject known to be pregnant
- Life expectancy less than one (1) year
- Currently participating or anticipated to participate in any other clinical trial of a drug, device or biologic during the duration of this study
- Unwilling or unable to comply fully with study procedures and follow-up
Sites / Locations
- Vancouver General Hospital
Arms of the Study
Arm 1
Arm 2
Arm 3
Experimental
Active Comparator
Experimental
Standard cryoablation
Irrigated RF Ablation
Short Cryoablation
Patients randomized to the standard group will undergo cryoablation with target duration of 240 seconds. Once PVI is achieved a single "bonus" application of 240 seconds will be delivered after the rewarming phase (to +20oC).
Patients randomized to irrigated RF group will undergo standard wide circumferential PVI with an irrigated radiofrequency catheter
Patients randomized to the multiple-freeze group will undergo cryoablation with target duration of 120 seconds. Once PVI is achieved a single "bonus" application of 120 seconds will be delivered after the rewarming phase (to +20oC).