Cryoballoon Ablation of Pulmonary Veins After Failed RF Ablation in Patients With Paroxysmal AF

Study Overview
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Brief Summary
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The aim of this prospective randomized double-blind study was to compare the efficacy and safety of cryoballoon ablation with the RF approach in the treatment of paroxysmal AF after failed first radiofrequency ablation.

Official Title
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Cryoballoon Ablation of Pulmonary Veins After Failed Radiofrequency Ablation in Patients With Paroxysmal Atrial Fibrillation

Conditions
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Paroxysmal Atrial Fibrillation

Intervention / Treatment
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* Procedure: cryoballoon ablation
* Procedure: Radiofrequency ablation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Previous failed first radiofrequency ablation procedure (only circumferential PV isolation without linear lesions) in patients referred for second catheter ablation of AF > 3 months after first PVI Exclusion Criteria: Congestive heart failure Ejection fraction <35% Left atrial diameter >60 mm

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Cryoballoon group<br> | Procedure: cryoballoon ablation<br>* In Cryo group, 28mm balloon was introduced into the PV ostium with the best possible occlusion of the PV. Every step was controlled by fluoroscopy. Cryoenergy was applied for maximal 6 minutes per application for 2 times, resulting in a circumferential ablation lesion. Before the right superior vein was treated, a quadripolar catheter was placed in the superior vena cava to continuously stimulate the right phrenic nerve during cryoapplication. The application was stopped immediately in the case of diminished diaphragm movements.<br>|
| Active Comparator: RF group<br> | Procedure: Radiofrequency ablation<br>* n RF group, reisolation of the PV was performed by identifying the breakthrough site. Radiofrequency energy was delivered at 43°C, 35 W, 0.5 cm away from the PV ostia at the anterior wall, and was reduced to 43°C, 30 W, 1 cm away from the PV ostia at the posterior wall, with a saline irrigation rate of 17 mL/min. Each lesion was ablated continuously until the local potential amplitude decreased by >80% or RF energy deliveries exceeded 40 s.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Recurrence of atrial tachyarrhythmia, including AF and left atrial flutter/tachycardia, after a second ablation procedure |  | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of complication after procedure between two groups |  | 1 year |