Ablación de fuentes de fibrilación auricular identificadas mediante mapeo secuencial de alta densidad: comparación in...

Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation, but recurrences are frequent. Ablating AF sources beyond PVI may prevent re-initiations. This proof-of-principle in silico study compares a novel source-based ablation approach to conventional strategies in preventing AF re-initiation.

We compared two conventional ablation strategies (PVI and PVI + posterior wall isolation [box ablation]) with our source-based approach. After PVI, a high-density mapping catheter was guided sequentially upstream of local repetitive conduction patterns until a source was identified. Located targets were ablated, connecting them to non-conducting boundaries. Strategies were compared based on their AF re-initiation rates after incremental pacing, and ablated and electrically isolated areas. Analyses were performed in 7 different scenarios with atria of different sizes, without (n=3) and with fibrosis (n=4) to assess different AF progression stages.

Compared to no ablation, PVI reduced initiation rates in non-fibrotic atria (23±8% control vs. 15±0% PVI) but was less effective with fibrosis (60±4% vs. 53±10%). Box ablation was not superior to PVI while isolating more of the left atrium (isolated area in PVI: 31.5±0.7% vs. box: 43.6±0.5%). Conversely, source ablation completely prevented AF initiation in all scenarios, achieving comparable left atrial isolation with box ablation (isolated area without fibrosis: 36.3±1.4%; with fibrosis: 43.2±2.6%) and including right atrial lesions. Although macro-reentrant tachycardias occurred frequently after source ablation, they were terminated with minimal lesions.

Ablating AF sources using our high-density mapping approach was more efficient in preventing AF re-initiation in silico than anatomy-based strategies.