The purpose of this prospective randomized study is to assess whether a new treatment strategy consisting of circumferential Pulmonary vein isolation (PVI), left ROof linear (RL), Mitral Isthmus linear (MIL), and left anterior SEptal linear (ASL) ablation and left atrial appendage (LAA) Device occlusion (PROMISED procedure) is superior to the PVI combined LAA closure in enhancing the long-term success rate of catheter ablation in non-paroxysmal atrial fibrillation (AF) patients.

Circumferential pulmonary vein isolation (CPVI) is an important radiofrequency catheter ablation strategy for AF. The recurrence rate of non-paroxysmal AF (non-PAF) after CPVI remains unsatisfactory, despite the use of additional strategies, such as linear ablation and complex fractionated atrial electrogram ablation. Non-PAF initiation and maintenance depend on a critical mass, which allows reentry. The left atrial anterior wall contains a series of substrates that are associated with AF, such as low-voltage zones, Bachmann's bundle, and the LAA, which are important for AF initiation and maintenance. Combining CPVI with left RL, left ASL, and MIL ablation can create a box lesion set on the anterior wall which compartmentalize the left atrial anterior wall into small regions to modify the substrate. We hypothesized that this substrate modification strategy would improve the success rate of non-PAF ablation. However, functional damage to the LAA resulting from the above-mentioned ablation strategy may increase stroke risk. The combined use of AF ablation and LAA occlusion is safe and can reduce stroke risk. Therefore, we examined the safety, feasibility, and efficacy of a new treatment strategy for non-PAF, defined as the CPVI; left ROof linear, Mitral Isthmus linear, and left anterior SEptal linear ablation; and LAA Device occlusion (PROMISED) procedure. Cases were prospectively treated in a 2-arm 1:1 design according to ablation strategy, divided into the Promised group (n = 83) or the PVI combined LAAC group (n =83).

Inclusion criteria:

1. Age > 18 years;

2. Persistent AF (AF duration > 7 days);

3. CHA2DS2-VASc score ≥2;

4. Presence of at least one of the following conditions:

   • Unsuitable for long-term standardized anticoagulation therapy;
   • Stroke or embolism still occurred based on long-term standardized anticoagulation therapy;
   • HAS-BLED score ≥3;
   • Unwillingness for long-term anticoagulation therapy;

Exclusion Criteria:

1. Previous atrial fibrillation ablation
2. Transthoracic echocardiography suggests that the anteroposterior diameter of the left atrium is greater than 60 mm;
3. persistent AF that lasts >10 years
4. Scheduled cardiac surgical intervention.
5. Documented left atrial thrombus/ left atrial appendage thrombus or another abnormality that precludes catheter/LAAC introduction
6. Life expectancy less than 1 year