Stability of Elevated Wall Shear Stress in Patients with Bicuspid Aortic Valve: Insights from a Multi-Year 4D Flow MRI Follow-Up Study

4D Flow MRI can identify aortic regions exposed to high wall shear stress (WSS) compared to age and sex-matched controls. This concept, known as WSS ‘heatmaps’, has recently shown potential to improve risk stratification in patients with bicuspid aortic valve (BAV). We examined the reproducibility of heatmaps in a cohort of 20 stable BAV patients with five consecutive 4D flow MRI scans and found no significant change over time. In addition, we found high reproducibility of WSS patterns and regions of elevated WSS across scans. Our findings, therefore, suggest that heatmaps can serve as a robust BAV risk measure.