Wall Shear Stress Measured with 4D Flow MRI Correlates with Biomarkers of Inflammation and Collagen Synthesis in Aortic Dilation

Motivation: Hemodynamics and circulating biomarkers could offer urgently needed improved risk-stratification in individuals with aortic dilation. Goal(s): To explore correlations between hemodynamics markers measured with 4D Flow MRI and circulating biomarkers in aortic dilation individuals with tricuspid aortic valves. Approach: Wall shear stress (WSS) parameters were assessed from 4D flow MRI in cases with dilation and controls. Blood plasma samples were used to quantify the inflammation biomarker IL-6 and several extracellular matrix biomarkers including collagen type I α1 chain (COL1α1). Results: IL-6 correlated to time-averaged WSS (r=0.54, p<0.001), whereas COL1α1 correlated to the oscillatory shear index (r=0.61, p<0.001). Impact: The observed correlations between 4D Flow MRI-derived wall shear stress and circulating biomarkers of inflammation and collagen synthesis raises the intriguing possibility that altered aortic hemodynamics causes biomarker leakage from the aortic tissue into the circulation.