Abstract TP131: Intracranial Plaque Enhancement on Vessel Wall MRI and the Oral Microbiome

Abstract

Introduction: Alterations in the oral microbiome are associated with the development of cardiovascular disease. Post-contrast plaque enhancement (PPE) on vessel wall MRI is associated with symptomatic intracranial atherosclerosis and increased risk of stroke recurrence, but the mechanism remains unknown. Hypothesis: We hypothesized that the oral microbiome in patients with PPE of the stroke parent artery would be distinct from those without PPE, offering insight into the pathophysiology of PPE. Methods: We conducted a prospective study of patients with ischemic stroke due to intracranial atherosclerosis, who underwent vessel wall MRI and oral swab within 14 days of stroke. MRI was interpreted by a blinded neuroradiologist and the oral microbiome was analyzed using validated genomic techniques. The diversity of bacterial species was tested with the Wilcoxon signed-rank test. Results: Thirty-two patients were included in our analysis, of which 20/32 had PPE (62%). No significant difference was found in bacterial species abundance between patients with or without PPE (p=0.745) (Figures 1+2), but 2/20 (10%) patients with PPE had elevated Mycoplasma species, which were absent in all the patients without PPE. Conclusions: Although we did not find an association between PPE and alterations in the oral microbiome, the identification of Mycoplasma in patients with PPE is of interest. Mycoplasma has been identified in histologic samples of ruptured atherosclerotic plaques. A larger study will be required to investigate this association and determine the impact of the oral microbiome on PPE when controlling for cardiovascular risk factors.