Evaluation of Optimized Strategies and Workflows for Catheter Ablation of Paroxysmal ＆ Persistent Atrial Fibrillation

Study Overview
=================
Brief Summary
-----------------
Clinical trials have demonstrated that performing catheter ablation for atrial fibrillation (AF) is a superior alternative to antiarrhythmic drugs for the maintenance of sinus rhythm, reduction of arrhythmia-related symptoms, and improvement of left ventricular ejection fraction, all while having a comparable safety profile. Therefore, catheter ablation has become the mainstream treatment for preventing AF recurrences. Nevertheless, despite its established efficacy, a significant number of AF recurrences following the initial ablation procedure can still occur due to factors such as pulmonary vein reconnections, or incomplete isolation. The success rate of single-procedure atrial arrhythmia-free survival particularly ranged from 40% to 66% in persistent AF ablation. However, The surgical Cox maze III procedure has been established to be an effective curative strategy for AF with an AF-free survival rate of more than 95%. The main reason is the difficulty of creating continuous, transmural, and durable lesions by catheter ablation, especially when the procedure is performed on some complex anatomical structures in which epicardial muscular bundles may serve as components of the reentrant circuits. The durability of the conduction block is a crucial factor for long-term effective AF ablation since previous studies reported that the reconnected Pulmonary veins contributed to the atrial tachycardia recurrence after persistent AF ablation. In addition, it is possible that the inadequate lesions accidentally produce new arrhythmogenic substrates. Therefore, new and better techniques are always chosen to minimize the reconnection of Pulmonary vein isolation (PVI) and additional ablation. In recent years, to improve the clinical outcomes following the initial ablation procedure, various advancements in techniques and technologies have been introduced. These include the use of contact force-sensing catheters, an ablation index-guided high-power ablation strategy, steerable guiding sheaths, intracardiac echocardiography catheters, and the incorporation of more extensive ablation. However, there is no standardized workflow in place, which can limit the effectiveness of AF ablation when performed by physicians in different medical centers. The investigators meticulously optimized every aspect of the catheter ablation process for AF, striving to enhance catheter operability and stability to generate continuous and transmural lesions akin to surgical intervention. For paroxysmal AF, the ablation strategy of PVI plus superior vena cava isolation is chosen while PVI, superior vena cava isolation, and linear ablation of linear ablations of the mitral isthmus, roofline and posterior wall line of the left atrium, and cavotricuspid isthmus (CTI) for persistent AF. Any symptomatic or asymptomatic atrial arrhythmia lasting more than 30 seconds was regarded as an AF recurrence after a 3-month blanking period. The primary outcome was defined as 12-month atrial arrhythmia-free survival. The secondary outcomes include the block rate of PVI, superior vena cava isolation, and all linear ablations.

Official Title
-----------------
Evaluation of Optimized Strategies and Workflows for Catheter Ablation of Paroxysmal ＆ Persistent Atrial Fibrillation

Conditions
-----------------
Atrial Fibrillation

Intervention / Treatment
-----------------
* Procedure: Pulmonary vein isolation plus superior vena cava isolation
* Procedure: PVI, superior vena cava isolation, and linear ablation of linear ablations of the mitral isthmus, roofline and posterior wall line of the left atrium, and cavotricuspid isthmus


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Radiofrequency catheter ablation for the first time Palpitation, chest tightness and other symptoms that can't be controlled by antiarrhythmic drugs Exclusion Criteria: Thrombosis in left atrium Left ventricular ejection fraction of < 35% Abnormal thyroid function Previous history of AF radiofrequency ablation and CABG Severe valvular heart disease or postoperation prosthetic valve surgery Left atrium diameter of > 65 mm or the volume of > 200 ml

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

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Paroxysmal AF group<br>AF that terminates spontaneously or with intervention within 7 days of onset | Procedure: Pulmonary vein isolation plus superior vena cava isolation<br>* Pulmonary vein isolation plus superior vena cava isolation<br>|
| Persistent AF group<br>AF that is continuously sustained beyond 7 days, including episodes terminated by cardioversion (drugs or electrical cardioversion) after ≥7 days | Procedure: PVI, superior vena cava isolation, and linear ablation of linear ablations of the mitral isthmus, roofline and posterior wall line of the left atrium, and cavotricuspid isthmus<br>* PVI, superior vena cava isolation, and linear ablation of linear ablations of the mitral isthmus, roofline and posterior wall line of the left atrium, and cavotricuspid isthmus<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| AF recurrence | Any symptomatic or asymptomatic atrial arrhythmia lasting more than 30 seconds after a 3-month blanking period | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| initial block rate | initial block rate of pulmonary veins isolation, superior vena cava isolation and additional ablation lines | intraoperation | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
atrial fibrillation, catheter ablation, optimized strategies and workflows