An Experimental Model of Human Aortic Dissection.

Abstract

Vascular diseases such as aortic dissections, aneurysms and stenosis are becoming frequent disorders in the industrialized world, and aortic diseases constitute an emerging share of these. An acute aortic dissection of the ascending aorta has an increasing mortality rate of 1% to 2% per hour after symptom onset. Determining whether an aortic dissection is at risk for rupture is not straightforward, and a better understanding of the role of thrombus, vessel geometry and wall components, entry tears, and other features of the diseased aorta is needed. The focus of this dissertation is to build an experimental bench top model of an aortic dissection which provides a fundamental knowledge of the flow characteristics and flap behavior under various physiological conditions. This model may help to emulate the forces and appearance of a dissection and explain the flow/pressure events that affect the stability or progression of a dissection. The operation of such a model will permit ranking the variables that determine the evolution of a dissection towards aneurysm or rupture. The mechanical properties of the polydimethylsiloxane (PDMS) material used to create experimental models of aortic dissections were investigated in the range of physiological parameters. This research may also be used as a benchmark to validate numerical models of aortic dissection. It also paves the road for researchers in the area of imaging to determine the elastic modulus of a living in-vivo arterial wall based on dynamic DICOM files in a non-invasive manner using high resolution CT scans.