Liner Ablation Using Contact-force in Atrial Fibrillation

Study Overview
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Brief Summary
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Linear ablation is frequently used in the procedure for persistent atrial fibrillation. However, it has a limitation because of technical difficulty. Incomplete block is common and an important cause of atrial tachycardia. The association between contact force values and successful linear block has not been revealed yet. We aim to the effectiveness and safety of linear ablation by using CF sensing catheter.

Detailed Description
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Catheter ablation is currently accepted as a treatment option for symptomatic atrial fibrillation. Linear ablation is frequently used in the procedure for persistent atrial fibrillation. Multiple studies have shown benefit of linear ablation. However, it has a limitation because of technical difficulty. Incomplete block is common and an important cause of atrial tachycardia. Contact-force (CF) monitoring during procedure has recently been available. This technology appears to significantly decrease procedure time and short term reconnection incidence in pulmonary vein (PV) isolation. It also helped to resolve the cause of PV reconnection. Some reports demonstrated that the association between reconnection and lower CF value. Linear ablation has more variation to interrupt block and reconnection was more often than PV isolation. The association between CF values and successful linear block has not been revealed yet. In addition, the investigators aim to the effectiveness and safety of linear ablation by using CF sensing catheter.

Official Title
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Left Atrial Liner Block Using Contact-force Catheter in Ablation for Atrial Fibrillation

Conditions
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Persistent Atrial Fibrillation

Intervention / Treatment
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* Procedure: Pulmonary vein isolation
* Procedure: Contact force assisted left atrial linear ablation
* Procedure: left atrial linear ablation without contact force monitoring


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients age is18 years or greater Patients with persistent AF (AF episode lasting > 7 days) Patients with symptomatic AF that is refractory to at least one antiarrhythmic medication Patients with recurrent or sustained arrhythmia after pulmonary vein isolation Patients undergoing a first-time ablation procedure for AF At least one episode of AF must have been documented by ECG, Holter, loop recorder, telemetry, trans telephonic monitoring (TTM), or implantable device within last 2 years of enrollment in this investigation Patients must be able and willing to provide written informed consent to participate in this investigation Exclusion Criteria: Patients with long-standing persistent AF; Long-standing persistent AF will be defined as a sustained episode lasting more than 3 years. Patients for whom cardioversion or sinus rhythm will never be attempted/pursued; Patients with AF felt to be secondary to an obvious reversible cause Patients with contraindications to systemic anticoagulation with heparin or warfarin or a direct thrombin inhibitor; Patients with left atrial size ≥ 60 mm (2D echocardiography, parasternal long axis view) Moderate to severe valvular disease Reduced left ventricular function (ejection fraction <40%) Patients who are pregnant. Pregnancy will be assessed by patients informing the physicians.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Contact force assisted linear ablation<br>Left atrial linear ablation performed using the contact force sensing catheter after pulmonary vein isolation | Procedure: Pulmonary vein isolation<br>* A pulmonary vein isolation procedure will be performed using radiofrequency ablation with contact force monitoring.<br>Procedure: Contact force assisted left atrial linear ablation<br>* Left atrial linear ablation (Roof line and Anterior line) after pulmonary vein isolation during catheter ablation for persistent atrial fibrillation monitoring contact force.<br>|
| Active Comparator: control<br>Left atrial linear ablation performed using the catheter without contact force sensing after pulmonary vein isolation | Procedure: Pulmonary vein isolation<br>* A pulmonary vein isolation procedure will be performed using radiofrequency ablation with contact force monitoring.<br>Procedure: left atrial linear ablation without contact force monitoring<br>* Left atrial linear ablation (Roof line and Anterior line) after pulmonary vein isolation during catheter ablation for persistent atrial fibrillation without monitoring contact force.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Freedom from atrial fibrillation/atrial tachycardia | Freedom from any documented episode of atrial fibrillation/atrial tachycardia occurring after a single ablation procedure and lasting longer than 30 seconds with/without antiarrhythmic medication | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total radiofrequency energy | Total radiofrequency energy to achieve bidirectional block of linear lesion in left atrium | 12 months | 
| Total force value | Total force value for complete block of linear lesion | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Persistent Atrial Fibrillation, Linear ablation, Catheter ablation, Contact force