Default Mode Network Disruption in Stroke-Free Patients with Atrial Fibrillation

Author(s)

Silva, Danilo S. ^{[1, 2]} ; Avelar, Wagner M. ^{[1, 2]} ; de Campos, Brunno M. ^{[3, 1]} ; Lino, Ana Paula B. L. ^[4] ; Balthazar, Marcio L. F. ^{[3, 1]} ; Figueiredo, Marcio J. O. ^[4] ; Cendes, Fernando ^{[3, 1]} ; Coan, Ana Carolina ^{[3, 1]}

Affiliation

^[1] Univ Estadual Campinas, Brazilian Inst Neurosci & Neurotechnol, BRAINN, Campinas, SP - Brazil

^[2] Univ Estadual Campinas, Dept Neurol, Neurovasc Grp, UNICAMP, Campinas, SP - Brazil

^[3] Univ Estadual Campinas, Dept Neurol, UNICAMP, Neuroimaging Lab, Campinas, SP - Brazil

^[4] Univ Estadual Campinas, Dept Cardiol, UNICAMP, Campinas, SP - Brazil

• Document type: Journal article
• Source: CEREBROVASCULAR DISEASES; v. 45, n. 1-2, p. 78-84, 2018.
• Web of Science Citations: 2

Abstract

Background: Atrial fibrillation (AF) is a widely accepted risk for causing stroke. However, recent studies show AF as a risk factor for dementia, even without causing stroke. The mechanisms by which dementia develops in stroke-free patients with AF are still poorly understood and the association of AF with abnormal function of brain networks activities, such as the default mode network (DMN), has not been previously studied. We aimed to determine whether, in the absence of stroke and dementia, patients with AF have abnormal resting-state brain networks compared to controls without AF. Methods: Twenty-one stroke-free patients with AF and 21 age-and sex-matched controls without AF underwent brain functional magnetic resonance imaging acquired at a 3.0 Tesla scanner. During the exam, the subjects were instructed to lie still with eyes closed. At first-level analysis, connectivity of the DMN was obtained for all subjects. Second-level analysis compared the DMN connectivity between AF patients and controls with a general linear model (two-sample t test, p < 0.05, False Discovery Rate corrected, minimum of 50 contiguous voxels). Results: Patients with AF compared with controls showed decreased connectivity in regions of the DMN including the frontal lobe (left medial frontal gyrus, left superior frontal gyrus and anterior cingulate), left angular gyrus, and bilateral precuneus. Conclusions: Stroke-free patients with AF have evidence of abnormal DMN connectivity. This study adds evidence to the occurrence of cerebral dysfunction in patients with AF. (c) 2018 S. Karger AG, Basel (AU)

• FAPESP's process: 13/00099-7 - EEG-fMRI in the pre-operatory evaluation of patients with focal refractory epilepsies
• Grantee: Ana Carolina Coan
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/07559-3 - BRAINN - The Brazilian Institute of Neuroscience and Neurotechnology
• Grantee: Fernando Cendes
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC