Atrial Fibrillation Initiation Arises From Reentry at Patient-Specific Regions With Steep Repolarization Gradients Identified During Sinus Rhythm

The authors aimed to identify the mechanisms and substrates responsible for the initiation of atrial fibrillation (AF) by examining patient-specific regions during sinus rhythm. They found that AF consistently originated from localized sites with steep repolarization gradients, which were associated with reentry mechanisms, and demonstrated that targeted ablation of these sites led to significant freedom from atrial arrhythmia. This research supports the shift towards individualized, substrate-guided ablation strategies in AF treatment.