Abstract 16305: The Role of Left Atrial Fibrosis Progression Detected by LGE-MRI on the Post-Ablation Atrial Fibrillation Recurrence

• Published in: Circulation (New York, N.Y.) N.Y.), 2018-11, Vol.138 (Suppl_1 Suppl 1), p.A16305-A16305
• Main Authors: Kheirkhahan, Mobin, Goldooz, Matin, Peritz, David C, Baher, Alex, Morris, Alan K, Loveless, Bosten A, Kaur, Gagandeep, Csecs, Ibolya, Chelu, Mihail G, Marrouche, Nassir F
• Format: Article
• Language: English
• ISSN: 0009-7322; 1524-4539

IntroductionLeft atrial (LA) fibrosis is thought to be a substrate for Atrial Fibrillation (AF) and its ablation emerges as a complementary method for AF management. However, LA fibrosis often continues to increase after ablation and likely affects maintenance of sinus rhythm.HypothesisWe examined how regression and progression of LA fibrosis affected AF recurrent.MethodsLA enhancement was quantified with Late Gadolinium Enhancement MRI (LGE-MRI) for 127 consecutive AF patients who underwent first time AF ablation. Quantification was done before ablation, 3 months post-ablation and then at least 12 months later. Regressed Fibrosis (RF) was defined as enhancement seen on the first (3-months) post-ablation scan but not on the 1-year post-ablation scan and New Fibrosis (NF) as the enhancement detected only on the 1-year post ablation scan.ResultsNF and RF showed no correlation with pre-ablation LA fibrosis. An increase of 1% NF increased the chance of AF recurrence by 3%. (HR 1.03, CI 95% 1 - 1.06, p = 0.05). RF alone showed no impact on future AF recurrence. Hazard ratio for AF recurrence increased when NF become greater (Figure 1-A). Additionally, patients with greater volume of NF (>21%, obtained from ROC analysis) experience significantly more recurrence post-ablation (AF freedom 37% vs 61%, p = 0.01, adjusted for cardiovascular risk factors) than those with less than 21% NF (Figure 1-B).ConclusionsAtrial fibrosis formation is an ongoing process and continues to evolve even after targeted ablation. This data suggests that new fibrosis formation after AF ablation (regardless of pre-ablation enhancement) is a novel marker of long-term procedural outcome and is an independent predictor of AF recurrence. It remains unclear whether contemporary AF management aimed at containing fibrotic structures, can help prolong the arrhythmia free period.