Abstract 2857: Incidence of Complete Circumferential Scar of the Pulmonary Vein Antra Following Ablation of Atrial Fibrillation: Assessment of Contiguous Lesions With Delayed Enhancement MRI
Background: Circumferential pulmonary vein ablation is the preferred atrial fibrillation (AF) ablation technique for many centers. However, the frequency of obtaining circumferential lesions using scar analysis with delayed enhancement MRI (DE-MRI) is unknown.
Methods: One hundred and forty-four patients underwent DE-MRI 3 months after AF ablation. The left atrium (LA) was segmented out and volume rendered. A color map was applied to illuminate scar tissue. Each pulmonary vein antra (PVA) was then analyzed for complete and contiguous scar lesions, as defined as no break or gap in the ablation lesion set.
Results: Only 10 patients (6.9%) had circumferential scar of all 4 PVA. Sixteen patients (11.1%) had 3 scarred veins, 19 patients (13.2%) had 2 scarred veins, 45 patients (31.3%) had 1 scarred vein, and 54 patients (37.5%) had no scarred veins. The majority of patients had less than one scarred vein (68.8%). The LIPV was most frequently circumferentially scarred PV occurring in 71/144 (49.3%) patients. The LSPV had complete scarring in 43/144 (29.9%) patients. The RIPV had complete scar in 32/144 (22.2%) patients. The RSPV was the most difficulty PV to achieve circumferential scarring occurring in only 17/144 (11.8%) patients. There was a greater extent of scar formation in the non-recurrence group for each PV analyzed compared to the recurrence group (p values and data).
Conclusion: From our preliminary data circumferential PV scarring persists only in a small number of patients at long-term follow up. Nevertheless, degree of LA ablation scarring seems to be a strong predictor for procedural success implicating the importance of LA substrate remodeling in achieving AF suppression.