Arrhythmias & electrophysiology
Atrial Fibrillation Initiation Arises From Reentry at Patient-Specific Regions With Steep Repolarization Gradients Identified During Sinus Rhythm
Authors' conclusion
AF initiation arises from a localized, patient-specific substrate capable of supporting reentry that can be identified using programmed stimulation during sinus rhythm. These findings provide a mechanistic basis for transitioning from empiric to individualized, substrate-guided ablation strategies.
Study context
- Population
- Patients with atrial fibrillation (AF) and controls; exploratory cohort of redo patients with durable pulmonary vein isolationpatients with AF 57 · controls 24 · redo patients with durable pulmonary vein isolation (PVI) (exploratory cohort) 24
- Participants
- 57 / 24 / 24
- Exposure
- initiation and noninitiation sites
- patients with AFn = 57
- controlsn = 24
- redo patients with durable PVIn = 24
Methodological detailsexploratory cohort
- Exploratory cohort
Main finding
As reported in the abstract
AF initiation sites
Discrete, patient-specific sites per patient
1.8 ± 1.0
Share of tested locations
2.8%
Observational data: associations, not effects.
Further findings
| Outcome | Patients with AF | Controls | Redo patients with durable PVI | |
|---|---|---|---|---|
| Steep repolarization gradients (SRGs; AERP difference ≥50 milliseconds over ≤10 millimeters) | 91.7% | 8.3% | Not reported in the abstract | redo patients with durable PVI: not reported in the abstract |
- Steep repolarization gradients (SRGs; AERP difference ≥50 milliseconds over ≤10 millimeters) — share of all AF initiation episodes accounted for by SRGs
- 92.2%
- Freedom from atrial arrhythmia without antiarrhythmic drugs after ablation confined to identified SRG sites (redo patients with durable PVI) · median follow-up of 489 days
- 87.5%
- Steep repolarization gradients (SRGs; AERP difference ≥50 milliseconds over ≤10 millimeters): P < 0.001
Steep repolarization gradients (SRGs; AERP difference ≥50 milliseconds over ≤10 millimeters)
- Low bipolar voltage was non-discriminatory
SRG site location in redo patients with durable PVI
- Left atria
- 70%
- Right atria
- 30%
Original publication
Atrial Fibrillation Initiation Arises From Reentry at Patient-Specific Regions With Steep Repolarization Gradients Identified During Sinus Rhythm. JACC Clin Electrophysiol. Published 7 August 2026. doi:10.
Summarised from the published abstract; every number is checked against it