Additional Low Voltage Area Ablation in Older Patients With Paroxysmal Atrial Fibrillation
Condition: Paroxysmal Atrial Fibrillation
MeSH terms: Atrial Fibrillation
Study type: Interventional

Summary: 
      The primary objective of this investigation is to compare the efficacy of two different AF
      ablation strategies in older patients with paroxysmal AF: Pulmonary vein isolation alone
      versus additional low-voltage substrate modification during sinus rhythm
    

Detailed description: 
      BACKGROUND: Atrial fibrillation (AF) is the most common cardiac rhythm disorder. Catheter
      ablation to the pulmonary veins isolation (PVI) electrically from the left atrium (LA) has
      been shown to be an effective treatment for paroxysmal AF (PAF). The consensus is that PVI
      alone is the main strategy for PAF ablation. Based on the results from our pilot study and
      STABLE-SR trial, that low-voltage modification beyond CPVI is very promising for persistent
      AF ablation. Whether the low voltage area modification combined with PVI improves outcomes is
      unclear in older patients with PAF.

      AIM OF THE STUDY: The primary objective of this investigation is to compare the efficacy of
      two different AF ablation strategies in older patients with PAF: PVI alone versus additional
      low-voltage substrate modification during sinus rhythm. The primary endpoint is freedom from
      AF and/or ATs with or without antiarrhythmic drugs (AADs) at 12 months after a
      single-ablation procedure. AF and/or AT occurring in the first 3 months after the ablation
      (blanking period) was censored. Each atrial tachyarrhythmia episode lasts > 30 seconds
      monitored by ECG, 24-Holter or 7 days-Holter was defined as recurrence. The secondary
      endpoint are incidence of periprocedural complications, including stroke, PV stenosis,
      cardiac perforation, esophageal injury and death; procedure time; fluoroscopy time (including
      the total fluoroscopy time, during CPVI and after CPVI); the occurrence of the conversion
      from AF to AT, and its relationship with long-term outcome; the scar distribution and the
      relationship of success rate in older PAF patients.

      STUDY DESIGN: This is a randomized, prospective, parallel, single-blind multicenter design.
      The expected freedom from atrial fibrillation in older patients after one ablation procedure
      was 75% for PVI. Previous study did not include a group assigned to isolation plus additional
      low-voltage substrate modification during sinus rhythm, so freedom form AF for this procedure
      was estimated from the literature at 85%. A log-rank test was used for sample-size
      calculation. To test whether the isolation plus low-voltage substrate modification was
      superior to isolation only. Then the 369 patients were needed, with a randomization ratio of
      1:1, for the study to have a power of 90% at a two-sided alpha level of 0.05. Assuming a
      dropout rate of 15%, we need 434 patients. Patients are randomized in a 1:1 fashion into one
      of the investigation arms: CPVI plus low-voltage substrate modification in the left atrium
      during SR and CPVI alone. Follow-up for these patients includes visits at 3 m, 6 m, 9 m, 12
      m.
    

Intervention name(s): CPVI plus low-voltage substrate modification; CPVI alone
Intervention type(s): Procedure; Procedure
Intervention description(s): CPVI plus low-voltage substrate modification in the left atrium during SR; circumferential pulmonary vein isolation
Other intervention name(s): CPVI plus additional low-voltage substrate modification
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Treatment
Keywords: substrate modification; pulmonary vein isolation; ablation; Paroxysmal Atrial Fibrillation