Cerebrovascular Diseases · Jul 20, 2026

Covert Embolic Brain Infarcts, Remote Cortical Thinning, and Cognitive Impairment in Atrial Fibrillation: An Analysis of the Swiss-AF Cohort

By Sinnecker T, Aeschbacher S, Springer A et al.

INTRODUCTION: Patients with atrial fibrillation (AF) exhibit a notable prevalence of both (covert) brain infarcts and white matter hyperintensities (WMHs). They face an elevated risk of cognitive decline and dementia, yet the pathogenesis remains largely unknown. Here, we aimed to investigate a potential relationship between lesion location of embolic brain infarcts or WMHs and (i) remote cortical volume using a tract-based analysis, as well as (ii) global cognitive function using voxel-based lesion-symptom mapping. METHODS: This is a cross-sectional analysis from a prospective, multicenter cohort study of unselected patients with AF (Swiss-AF) enrolling 1,716 patients with eligible MRI data (mean age 73 ± 8 years, 27% women, 90% anticoagulated). We assessed the association of brain lesions including embolic brain infarcts and WMHs in specific white matter tracts with remote cortical volume by using LASSO regression. In addition, voxel-based lesion-symptom mapping was deployed to assess the effect of WMH location in relationship to embolic brain infarcts on cognitive function. RESULTS: We observed WMH in 1,699 of 1,716 (99%) and embolic brain infarcts in 395 of 1,716 (23%) patients. The presence of embolic infarcts within most fiber tracts (mean, IQR: 55, 8-66 cm3) accounted for more variability in remote cortical volumes than WMH regional volume (mean, IQR: 366, 63-657 cm3) despite their lower volume. In addition, while the presence of WMH was initially associated with cognitive function across most brain regions (61.8% of voxels with significant association), when adjusting models for the presence of embolic infarcts, only a minor fraction of WMH remained significantly associated with cognitive function (23.6% of voxels). CONCLUSIONS: Among patients with AF, (covert) embolic brain infarcts and WMHs are associated with remote cortical atrophy and with lower cognitive performance. The disruption of brain networks through embolic infarcts seems to contribute to cognitive impairment in patients with AF.

doi.org/10.1159/000553651Open accessPubMed 42475254Mechanisms