Ablation Index Guided High Power Ablation for Pulmonary Vein Isolation in Patients With Atrial Fibrillation

Study Overview
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Brief Summary
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The investigators will compare the ablation time during pulmonary vein isolation of Ablation Index-guided high power ablation with those with conventional ablation. Ablation time of conventional group will be used from OPTIMUM study. For secondary outcomes, acute outcomes of pulmonary vein isolation using two different strategies will be compared. During 1 year of follow-up in both groups, atrial fibrillation recurrence will be evaluated. The atrial fibrillation recurrence rate at 1 year after pulmonary vein isolation will be compared between the two groups. In addition, fluoroscopic time, procedure time, and complication rates for the high power ablation group will be compared with those with conventional power.

Detailed Description
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Ablation Index guided high power ablation will be performed in 70 patients with atrial fibrillation with prospectively and consecutively. A contact force-sensing catheter will be used. Ablation will be performed with point-by-point technique using Visitag automated annotation criteria as below; Ablation Index(AI) target: Anterior/roof : 450 AI Anterior near carina area : 500 AI Posterior/inferior/carina : 350 AI Posterior near carina area : 400 AI Area near esophagus :25W, 15sec or 300 AI (no further ablation if esophageal temperature increase more than 39°C) Interlesion distance ≤ 4.5mm VISITAGTM settings 2.5mm stability range 7 sec stability time FOT 25%, 3g force Tag size 2mm Ablation parameters are preset as below; RF power range: 40W at anterior/roof, 30W at posterior/inferior, 25W at near esophagus area (decrease power 5W by operator decision) Target contact force range: 10-20 g Flow rate: 8 ml/min for STSF < 30W 15 ml/min for STSF ≥ 30W Acute reconnection will be analysed according to predefined segments. Subgroup analysis will be performed according to type of AF. Data of patients with paroxysmal atrial fibrillation and persistent atrial fibrillation will be analysed separately, and investigate whether this new ablation strategy is effective in both group of patients. To compare outcomes with OPITMUM phase 2 study, the proportion of patients with paroxysmal and persistent atrial fibrillation would be 75% and 25%. Therefore, 53 patients with paroxysmal atrial fibrillation and 17 patients with persistent atrial fibrillation will be enrolled in this study.

Official Title
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Ablation Index Guided High Power Ablation for Pulmonary Vein Isolation in Patients With Atrial Fibrillation

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Procedure: Catheter Ablation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with symptomatic paroxysmal or persistent AF who failed anti-arrhythmic agents Exclusion Criteria: Patients who had previous ablation for AF Patients with left atrial diameter more than 50 mm Inability or unwillingness to receive oral anticoagulation with a vitamin K antagonist (VKA) or non-VKA (NOAC) agent Known severe left ventricular systolic dysfunction (ejection fraction <35%) Pregnancy

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 80 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: Non-Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: High power ablation<br>Ablation Index guided high power ablation (radio frequency energy: Left atrium anterior segment and roof: 40W, Left atrium inferior/posterior: 30W, near esophagus: 25W) | Procedure: Catheter Ablation<br>* Catheter Ablation is a procedure used to remove or terminate a faulty electrical pathway from sections of the hearts of those who are prone to developing cardiac arrhythmias<br>|
| Active Comparator: Conventional ablation<br>Conventional ablation applying 30-35W strategy for Left atrium anterior segments. | Procedure: Catheter Ablation<br>* Catheter Ablation is a procedure used to remove or terminate a faulty electrical pathway from sections of the hearts of those who are prone to developing cardiac arrhythmias<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ablation time | To compare ablation time of ablation index guided high power ablation for pulmonary vein isolation in patients with atrial fibrillation | during procedure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| residual potential after first pass pulmonary vein encirclement | segment which observed residual potential after first pass pulmonary vein encirclement during procedure (based on predefined pulmonary vein segments) | during procedure | 
| acute pulmonary vein reconnection | segment which observed early re-connection during procedure (based on predefined pulmonary vein segments) time frame: during procedure (20-30 minutes after pulmonary vein isolation) | 1 year | 
| any atrial fibrillation/atrial tachycardia recurrence | detected by 12-lead electrocardiogram or 24-hour holter monitoring | 1-year after index procedure | 
| Total time | Total ablation time, fluoroscopic time, and procedure time | during procedure | 
| Rate of Complication | Complications associated with procedure.(bleeding, cardiac tamponade, etc.) | 1 year |