PeAF-BOX: Feasibility, Safety and Efficacy of PVI + Box Ablation in Persistent Atrial Fibrillation

Title: PeAF-Box. Feasibility, Safety and Efficacy of Isolating the Left Atrial Posterior Wall (PWI) added to Pulmonary Vein Isolation (PVI) as First-Line Strategy in Treatment of Persistent Atrial Fibrillation (PeAF)

Design: A prospective, observational, single center, unblinded, clinical study with 3 years of follow-up and two interventional procedures: An index ablation procedure and a reassessment/ reablation procedure after 6 months.

Background: In patients with PeAF the effect of first-line ablation with pulmonary vein isolation (PVI) is smaller than in patients with paroxysmal atrial fibrillation (PAF), where PVI alone is effective in reducing symptoms and increasing quality of life. Adding PWI to PVI is increasingly used despite concerns about safety and efficacy.

Objectives: (1) To use PVI + PWI as first-line ablation-strategy in participants with PeAF and to assess the feasibility of obtaining that goal. (2) To assess the safety of applying this lesion set - in terms of heat-induced injury to the esophagus - using esophagoscopy. 3) To asses arrhythmia burden using continuous monitoring for 3 years after ablation. (4) To assess the durability of the PVI + PWI lesion set by a relook/ reablation procedure after 6 months. (5) To follow the effect of PVI + PWI on participants' quality of life over three years.

Study site: Dept of Cardiology - Electrophysiology Laboratory, Gentofte Hospital, University of Copenhagen.

Study population: 24 patients referred for ablation of PeAF are asked for informed consent for these elements that surpass standard treatment in PeAF: (1) Taking amiodarone for 3 weeks prior to the index procedure to 3 weeks after the procedure, (2) Additional ablation with PWI compared to standard first-line therapy with PVI only. (3) Implantation of an implantable cardiac monitor (ICM), (4) Post-procedure esophagoscopy, (5) Regular clinic visits for 3 years post procedure, (6) Undergoing an interventional relook/ reablation procedure 6 months after the index procedure.

Anticoagulation drugs during the procedure and follow up: To prevent thromboses participants are prescribed periprocedural oral anticoagulant treatment to be continued for shorter or longer/lifelong periods according to the participants' risk of thrombosis (the CHA2DS2-VASC score).

Anti-arrhythmic drugs (AADs): Except from periprocedural amiodarone treatment, no AADs are allowed during the follow-up apart from occurrence of otherwise untreatable arrhythmias.


Eligibility Criteria:
Inclusion Criteria:

* Patients with symptomatic persistent atrial fibrillation (EHRA symptom class II or above)
* Prior failed treatment with at last one antiarrhythmic drug (Class I-IV)
* Clinical indication for ablation
* Persistent atrial fibrillation meeting both the following requirements:

  * One or more episodes of atrial fibrillation lasting longer than seven days, regardless of mode of termination
  * Estimated cumulated time in PeAF more than 3 months and less than 36 months

Exclusion Criteria:

* Contraindication for ablation
* Predominantly PAF phenotype
* Valvular Heart disease
* Previous ablation in heart
* Previous heart surgery (including valve surgery and coronary artery bypass grafting - CABG)
* Documented atrial flutter or other arrhythmia requiring ablation besides PVI
* Greatly enlarged left atrium on Trans thoracic Echocardiography (TTE ; diameter \> 52 mm in males and diameter \> 47 mm in females)
* LVEF \< 35%
* Implanted pacemaker or defibrillator
* Presence of intramural thombus, tumor or other abnormality precluding catheter introduction
* Pregnancy
* Intolerance to Amiodarone
* Unstable angina pectoris
* Myocardial infarction within 3 months of inclusion
* History of blood clotting or bleeding anomalies
* Malignant disease (non metastatic skin cancer excluded)
* Severe obesity (Mody mass index \> 35 kg/m\^2)
* Active systemic infection
* Renal insufficiency (serum creatinine \> 150 mmoles/liter)
* Psychiatric illness
* Substance abuse
* Participation in other clinical trials