Fluid dynamics of aortic root dilation in Marfan syndrome

TL;DR

This study investigates how Marfan syndrome-induced aortic root dilation alters blood flow dynamics using in-vitro models, revealing the role of vorticity and flow changes in disease progression.

Contribution

It provides the first in-vitro analysis of fluid dynamic changes in dilated aortic roots mimicking Marfan syndrome, highlighting the impact of morphological alterations on flow patterns.

Findings

Vorticity from valve leaflets influences flow redirection.

Dilation causes significant changes in systolic and diastolic flow.

Altered flow patterns may contribute to vessel dilation and dissection risk.

Abstract

Aortic root dilation and propensity to dissection are typical manifestations of the Marfan Syndrome (MS), a genetic defect leading to the degeneration of the elastic fibres. Dilation affects the structure of the flow and, in turn, altered flow may play a role in vessel dilation, generation of aneurysms, and dissection. The aim of the present work is the investigation in-vitro of the fluid dynamic modifications occurring as a consequence of the morphological changes typically induced in the aortic root by MS. A mock-loop reproducing the left ventricle outflow tract and the aortic root was used to measure time resolved velocity maps on a longitudinal symmetry plane of the aortic root. Two dilated model aortas, designed to resemble morphological characteristics typically observed in MS patients, have been compared to a reference, healthy geometry. The aortic model was designed to quantitatively reproduce the change of aortic distensibility caused by MS. Results demonstrate that vorticity released from the valve leaflets, and possibly accumulating in the root, plays a fundamental role in redirecting the systolic jet issued from the aortic valve. The altered systolic flow also determines a different residual flow during the diastole.