Anticoagulation After RFCA

Study Overview
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Brief Summary
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The anticoagulation therapy is needed when rhythm control strategy is applied in atrial fibrillation patients but adverse events such as major bleeding exist. This study aims to examine the prognostic inpact of the duration of anticoagulation after radiofrequency ablation of paroxismal atrial fibrillation in patients with low thromboembolic risk. Paroxismal atrial fibrillation patients with 0 or 1 CHADS2-Vasc score undergoing radiofrequency ablation is randomized into one month anticoagulation group and two months anticoagulation group after the procedure. Thromboembolic event and adverse event including major or minor bleeding would be compared.

Detailed Description
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Catheter based radiofrequency ablation has been used in more than a decade as a rhythm control therapy. Recently, superior outcome to medical therapy has been constantly reported and the radiofrequency catheter ablation (RFCA) became popular globally. It is recommended to anticoagulate patients who received RFCA for atrial fibrillation at least two months after the procedure. However, a few reports suggest anticoagulation in selective patients according to CHADS2-Vasc score. Anticoagulants prevent thromboembolic event in atrial fibrillation but the risk of bleeding is increased in company. There is controversy in the duration of anticoagulation after RFCA of atrial fibrillation. The investigators aimed to investigate the association with thromboembolic and bleeding event of anticoagulation duration after RFCA of atrial fibrillation in patients with low thromboembolic risk. Paroxismal atrial fibrillation patients with 0 or 1 CHADS2-Vasc score who are undergoing RFCA are included and randomized by 1:1 ratio to one month anticoagulation group and two months anticoagulation group after RFCA. Any patient with an evidence of intracardiac thrombus is excluded. The primary endpoint is thromboembolic event in 6 months after RFCA and the secondary endpoint is bleeding event in 6 months after RFCA.

Official Title
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Duration of Anticoagulation Therapy Following Catheter Ablation of Atrial Fibrillation; Randomized Controlled Trial

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Drug: Oral anticoagulant


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Under 75 years old Patients undergoing RFCA for paroxismal atrial fibrillation CHADS-Vasc score 0-1 Exclusion Criteria: Presence of intracardiac thrombus

Ages Eligible for Study
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Maximum Age: 74 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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 1-month anticoagulation group<br>Anticoagulation using warfarin or non-VKA oral anticoagulant for 1 month after radiofrequency catheter ablation of paroxismal atrial fibrillation and then stop anticoagulation. | Drug: Oral anticoagulant<br>* 1:1 randomization to 1-month anticoagulation or 2-month anticoagulation after radiofrequency catheter ablation of paroxismal atrial fibrillation<br>|
| Active Comparator: 2-month anticoagulation group<br>Anticoagulation using warfarin or non-VKA oral anticoagulant for 2 months after radiofrequency catheter ablation of paroxismal atrial fibrillation and then stop anticoagulation | Drug: Oral anticoagulant<br>* 1:1 randomization to 1-month anticoagulation or 2-month anticoagulation after radiofrequency catheter ablation of paroxismal atrial fibrillation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Thromboembolic event | Composite of ischemic stroke, transient ischemic attack, or other systemic embolic events | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Major bleeding | bleeding events that result in a reduction in hemoglobin level of at least 20 g per liter, transfusion of at least 2 units of blood, or symptomatic bleeding in a critical area or organ | 6 months |