de Beaufort H W L, Nauta F J H, Conti M, Cellitti E, Trentin C, Faggiano E, van Bogerijen G H W, Figueroa C A, Moll F L, van Herwaarden J A, Auricchio F, Trimarchi S
Thoracic Aortic Research Center, Policlinico San Donato IRCCS, University of Milan, Italy; Department of Vascular Surgery, University Medical Center Utrecht, The Netherlands.
Thoracic Aortic Research Center, Policlinico San Donato IRCCS, University of Milan, Italy; Department of Vascular Surgery, University Medical Center Utrecht, The Netherlands; Departments of Biomedical Engineering and Surgery, University of Michigan, Ann Arbor, USA.
Eur J Vasc Endovasc Surg. 2017 Feb;53(2):199-205. doi: 10.1016/j.ejvs.2016.11.018. Epub 2016 Dec 24.
Reference values of aortic deformation during the cardiac cycle can be valuable for the pre-operative planning of thoracic endovascular aortic repair (TEVAR) and for facilitating computational fluid dynamics. This study aimed to quantify normal aortic extensibility (longitudinal extension) and distensibility (radial expansion), as well as pulsatile strain, in a group of 10 (>60 years) individuals with abdominal or thoracic aortic aneurysms.
ECG gated CT images of the thoracic aorta were reconstructed into virtual 3D models of aortic geometry. The centre lumen line length of the thoracic aorta and three longitudinal segments, and the aortic diameter and luminal areas of four radial intersections were extracted with a dedicated software script to calculate extensibility, longitudinal strain, distensibility, and circumferential area strain.
Mean extensibility and longitudinal strain of the entire thoracic aorta were 3.5 [1.3-6.8] × 10 N, and 2.7 [1.0-4.5]%, respectively. Extensibility and longitudinal strain were most pronounced in the ascending aorta (20.6 [5.7-36.2] × 10 N and 15.9 [6.6-31.9]%) and smallest in the descending aorta (4.4 [1.6-12.3] × 10 N and 2.2 [0.7-4.7]%). Mean distensibility and circumferential area strain were most pronounced at the sinotubular junction (1.7 [0.5-2.9] × 10 mmHg and 11.3 [3.3-18.5]%, respectively). Distensibility varied between 0.9 [0.3-2.5] × 10 mmHg and 1.2 [0.3-3.3] × 10 mmHg at the intersections in the aortic arch and descending aorta.
Pulsatile deformations in both longitudinal and circumferential directions are considerable throughout the thoracic aorta. These findings may have implications for pre-operative TEVAR planning and highlight the need for devices that can mimic the significant aortic longitudinal and circumferential strains.
心动周期中主动脉变形的参考值对于胸主动脉腔内修复术（TEVAR）的术前规划以及促进计算流体动力学可能具有重要价值。本研究旨在量化一组10名（年龄>60岁）患有腹主动脉瘤或胸主动脉瘤的个体的正常主动脉伸展性（纵向延伸）、扩张性（径向扩张）以及搏动应变。
将胸主动脉的心电图门控CT图像重建为主动脉几何形状的虚拟3D模型。使用专用软件脚本提取胸主动脉的中心腔线长度及三个纵向节段，以及四个径向交叉点的主动脉直径和管腔面积，以计算伸展性、纵向应变、扩张性和圆周面积应变。
整个胸主动脉的平均伸展性和纵向应变分别为3.5 [1.3 - 6.8]×10 N和2.7 [1.0 - 4.5]%。伸展性和纵向应变在升主动脉中最为明显（分别为20.6 [5.7 - 36.2]×10 N和15.9 [6.6 - 31.9]%），在降主动脉中最小（分别为4.4 [1.6 - 12.3]×10 N和2.2 [0.7 - 4.7]%）。平均扩张性和圆周面积应变在窦管交界处最为明显（分别为1.7 [0.5 - 2.9]×10 mmHg和11.3 [3.3 - 18.5]%）。在主动脉弓和降主动脉的交叉点处，扩张性在0.9 [0.3 - 2.5]×10 mmHg至1.2 [0.3 - 3.3]×10 mmHg之间变化。
整个胸主动脉在纵向和圆周方向上的搏动变形都相当可观。这些发现可能对TEVAR术前规划有影响，并突出了对能够模拟主动脉显著纵向和圆周应变的装置的需求。
