STAR Apollo™ Map-Guided Redo Ablation for Recurrent Persistent Atrial Fibrillation after Prior Pulmonary Vein Isolation: Procedural Feasibility, Safety, and Twelve-Month Rhythm Outcomes from a Prospective Multicenter Study (NCT05826665)

BACKGROUND Redo ablation for persistent atrial fibrillation (AF) that recurs after pulmonary vein isolation (PVI) has limited durable success, and adjunctive substrate strategies have not consistently improved outcomes. The STAR Apollo™ Mapping System (Rhythm AI Ltd) is an FDA-cleared technology that applies stochastic trajectory analysis of ranked signals to identify repetitive patterns of activation (RPAs) and early sites of activation (ESAs) that may indicate regions sustaining AF. OBJECTIVE To examine the procedural feasibility and safety, and to describe the 12-month rhythm outcomes, of STAR Apollo-guided redo ablation in patients with recurrent persistent AF after prior PVI. METHODS In this prospective, multicenter, observational study, patients with persistent AF recurring after one prior PVI (prior extra-pulmonary-vein ablation excluded) underwent pulmonary vein re-isolation, STAR Apollo mapping, and operator-directed adjunctive ablation. Because STAR mapping requires ongoing AF, the analysis was confined to the 50 patients (of 64 enrolled) in whom a STAR map was obtained; the 14 without a STAR map, because they were not in AF at the procedure, were excluded. Procedural parameters, safety, and rhythm at the 3-, 6-, and 12-month visits were recorded. RESULTS All 50 patients had one prior PVI and recurrent persistent AF; they were 68.8 ± 8.7 years of age, 35 (70.0%) male, with body-mass index 31.3 ± 5.5 kg/m2. Pulmonary vein reconnection was found and re-isolated in 46/50 (92.0%). The system identified a median of 3 (2-3) ESAs per patient, and STAR mapping added a median of 16 (13-21) minutes to a median total procedure of 125 (91-166) minutes. Sinus rhythm was restored without cardioversion in 23/50 (46.0%; AF terminated during ablation in 19/50 [38.0%] and spontaneously in 4/50 [8.0%]); 26/50 (52.0%) required cardioversion and 1/50 (2.0%) was not restored in the laboratory. Adjunctive lines included a roof line in 30/50 (60.0%) and a mitral isthmus line in 11/50 (22.0%). A procedural complication occurred in 1/50 (2.0%) (pericardial effusion). Among 40 patients assessed at 12 months, 33 (82.5%) were in sinus rhythm and symptom class improved to EHRA I in 23/30 (76.7%). By Kaplan-Meier estimation (single procedure; recurrence, repeat ablation or cardioversion counted as failure), freedom from AF was 95.3% (95% CI 82.5-98.8) at 6 months and 75.3% (95% CI 59.0-85.9) at 12 months. CONCLUSION In recurrent persistent AF after prior PVI, STAR Apollo-guided redo ablation was feasible and safe, added a modest mapping step, and was associated with sinus rhythm and symptom improvement in most patients at 12 months. Designed as a feasibility and safety study, and being single-arm, these data cannot establish the incremental efficacy of STAR guidance; the encouraging rhythm outcomes are hypothesis-generating and support a randomized comparison with PV re-isolation alone.