Neuropsychological effects of MRI-detected brain lesions after left atrial catheter ablation for atrial fibrillation: long-term results of the MACPAF study.

Background —Magnetic resonance imaging (MRI)-detected brain lesions are common following left atrial catheter ablation (LACA) for symptomatic atrial fibrillation. The clinical relevance of these acute ischemic lesions is not fully understood, but ablation-related cerebral injury could contribute to cognitive dysfunction. Methods and Results —In the prospective "Mesh Ablator versus Cryoballoon Pulmonary Vein Ablation of Symptomatic Paroxysmal Atrial Fibrillation" study, serial 3 Tesla brain MRIs and neuropsychological assessment were performed to analyze the rate of ablation-related brain lesions and their impact on cognitive function. Thirty-seven patients with paroxysmal atrial fibrillation (median age 63.0 (IQR 57-68); 41% female; median CHA2DS2VASc score 2 (IQR 1-3)) underwent 41 ablation procedures according to study criteria. None of these patients had overt neurological deficits following ablation. High-resolution diffusion-weighted imaging (DWI), performed within 48 hours post-ablation, showed that new brain lesions (range 1-17) were present in 16 (43.2%) patients following 18 (43.9%) LACA procedures. Follow-up MRI at 6 months (median 6.5, IQR 6-7) revealed that 7 (12.5%) of the 56 total acute brain lesions post-ablation formed a persistent glial scar in 5 (31.3%) patients. Large DWI lesions and a corresponding FLAIR lesion 48 hours post-ablation predicted lesion persistence on 6 month follow-up. Neither persistent brain lesions nor the ablation procedure itself had a significant impact on attention or executive functions, short term memory, or verbal and non-verbal learning after 6 months. Conclusions —Ablation-related acute ischemic brain lesions persist to some extent but do not cause cognitive impairment 6 months after the ablation procedure. Clinical Trial Registration Information —clinicaltrials.gov; Identifier: [NCT01061931][1]. [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT01061931&atom=%2Fcircae%2Fearly%2F2013%2F08%2F28%2FCIRCEP.113.000174.atom