Measurement of the Local Strain of the Porcine Thoracic Aorta During the Inflation Test

The aorta is the main artery and plays an important role in the blood circulatory system. Diseases of the aorta such as aortic aneurysm and aortic dissection have high mortality rates, hence the study of the mechanical properties of the aorta has been an active research area. In many previous studies, the aorta has been considered as a straight cylindrical tube undergoing uniform circumferential deformation and therefore uniform strain/stress distribution in the circumferential direction. However, recent biomedical imaging studies show that the aorta has circumferentially nonuniform deformation during the cardiac cycle [1] and the aortic wall distends asymmetrically [2]. Furthermore, it has been shown that the anterior wall displacement is larger than the posterior wall displacement [3]. These in vivo studies have raised yet another question as to whether nonuniform deformation is due to the inhomogeneous properties of the aortic wall or due to surrounding tissues.