Superior Vena Cava Isolation Plus Pulmonary Vein Isolation for Paroxysmal Atrial Fibrillation

Study Overview
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Brief Summary
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Pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) has limited success. The superior vena cava (SVC) has been identified as one of the most common non-pulmonary vein triggers for PAF. It is estimated that SVC isolation (SVCI) could improve the clinical results for patients with PAF. However, results from previous studies about SVCI remain controversial. It is possible that safety concerns for SVCI outweigh its benefits and lead to inadequate ablation. To address this issue, the introduction of a quantitative ablation index (AI) for SVCI may provide a solution. Therefore, we sought to initiate a retrospective, multi-center study, to explore the efficacy and safety of quantitative SVCI in addition to PVI in PAF.

Detailed Description
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Catheter ablation has emerged as an effective treatment for drug-refractory PAF and is recommended as first-line therapy by current guidelines. PVI is considered the cornerstone of catheter ablation for atrial fibrillation (AF). However, despite persistent PVI, a subgroup of patients may experience recurrent AF due to focal ectopic discharges originating outside the pulmonary veins. Among the non-pulmonary vein triggers, the SVC stands out as a common culprit, making it a promising ablation target for maintaining sinus rhythm. Nevertheless, results from previous studies that evaluate the efficacy of SVCI showed conflicting results. One possible explanation is that SVC is adjacent to critical anatomy structures (such as the sinus node and the phrenic nerve), which raises safety concerns and often leads to inadequate ablation. Therefore, it is necessary to establish standardized ablation procedure for SVCI, ensuring both safety and efficacy. To address this issue, we proposed the concept of quantitative ablation for SVCI. By introducing AI as a quantitative measure, it is possible to achieve precise catheter ablation while minimizing the risk of procedure-related complications. The aim of this study was to investigate the safety and feasibility of this ablation strategy for PAF and its success rate. Participants with PAF will be consecutively enrolled.

Official Title
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Superior Vena Cava Isolation Plus Pulmonary Vein Isolation for Paroxysmal Atrial: a Multi-center Retrospective Study

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Procedure: Pulmonary vein isolation plus superior vena cava isolation
* Procedure: Pulmonary vein isolation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Symptomatic paroxysmal AF that are unresponsive to antiarrhythmic drugs (one or more than one). Willing to undergo catheter ablation for AF. Exclusion Criteria: History of any type of catheter ablation for cardiac arrhythmias. Sinus node dysfunction that requires permanent pacemaker implantation.

Ages Eligible for Study
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Minimum Age: 18 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Pulmonary vein isolation plus superior vena cava isolation<br> | Procedure: Pulmonary vein isolation plus superior vena cava isolation<br>* Pulmonary vein isolation plus superior vena cava isolation<br>|
| Pulmonary vein isolation<br> | Procedure: Pulmonary vein isolation<br>* Pulmonary vein isolation only<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| AT/AF recurrence | atrial fibrillation, atrial flutter, atrial tachycardia over 30s | 12 months |