- Question
- In patients with persistent atrial fibrillation, does adding MRI-guided ablation of atrial fibrosis to pulmonary vein isolation reduce atrial arrhythmia recurrence?
- Design
- Investigator-initiated, multicenter, randomized clinical trial of 843 patients at 44 academic and nonacademic centers in 10 countries. Masking was single-blind per the registry; follow-up extended through February 2021.
- Population
- Patients with symptomatic or asymptomatic persistent atrial fibrillation undergoing ablation (mean age 62.7 years; 21.1% women). Delayed-enhancement MRI was done in both groups before the procedure and at 3 months to assess ablation scar.
- Intervention
- Pulmonary vein isolation (PVI) plus MRI-guided atrial fibrosis ablation (421 patients).
- Control
- PVI alone, conventional catheter ablation (422 patients).
- Primary outcome
- Time to first atrial arrhythmia recurrence after a 90-day post-ablation blanking period. The primary safety outcome was a 30-day composite of stroke, pulmonary vein stenosis, bleeding, heart failure, or death.
- Results
- Atrial arrhythmia recurrence did not differ between groups: 43.0% with fibrosis-guided ablation plus PVI vs 46.1% with PVI alone (HR 0.95; 95% CI 0.77-1.17; P = .63). The efficacy analysis included 815 patients (96.9%) who completed the blanking period.
- Safety
- The safety composite was more frequent with fibrosis-guided ablation plus PVI (9 patients, 2.2%) than with PVI alone (0; P = .001). Six ischemic strokes (1.5%) occurred in the fibrosis group and none in the control group. Two deaths occurred in the fibrosis group, the first possibly related to the procedure.
- Conclusion
- MRI-guided fibrosis ablation added to PVI did not reduce atrial arrhythmia recurrence compared with PVI alone and was associated with more safety events.
- Why it matters
- The trial did not support MRI-guided fibrosis ablation for persistent atrial fibrillation and reinforced pulmonary vein isolation as the foundational strategy, discouraging this additional imaging-guided ablation.
Card generated automatically with AI from the abstract of the original publication and the trial registry; every figure was checked against those sources. It may contain errors: verify the data at the source before using it for clinical decisions.
Generated on October 18, 2026