Martufi G, Gasser T C, Appoo J J, Di Martino E S
Department of Civil Engineering and Centre for Bioengineering Research and Education, Schulich School of Engineering, University of Calgary, 2500 University Dr NW, Calgary, T2N1N4, Canada.
Biomech Model Mechanobiol. 2014 Oct;13(5):917-28. doi: 10.1007/s10237-014-0557-9. Epub 2014 Feb 15.
An aortic aneurysm is a permanent and localized dilatation of the aorta resulting from an irreversible loss of structural integrity of the aortic wall. The infrarenal segment of the abdominal aorta is the most common site of aneurysms; however, they are also common in the ascending and descending thoracic aorta. Many cases remain undetected because thoracic aortic aneurysms (TAAs) are usually asymptomatic until complications such as aortic dissection or rupture occurs. Clinical estimates of rupture potential and dissection risk, and thus interventional planning for TAAs, are currently based primarily on the maximum diameter and growth rate. The growth rate is calculated from maximum diameter measurements at two subsequent time points; however, this measure cannot reflect the complex changes of vessel wall morphology and local areas of weakening that underline the strong regional heterogeneity of TAA. Due to the high risks associated with both open and endovascular repair, an intervention is only justified if the risk for aortic rupture or dissection exceeds the interventional risks. Consequently, TAAs clinical management remains a challenge, and new methods are needed to better identify patients for elective repair. We reviewed the pathophysiology of TAAs and the role of mechanical stresses and mathematical growth models in TAA management; as a proof of concept, we applied a multiscale biomechanical analysis to a case study of TAA.
主动脉瘤是主动脉壁结构完整性不可逆转丧失导致的主动脉永久性局部扩张。腹主动脉肾下段是动脉瘤最常见的部位；然而，它们在胸主动脉升段和降段也很常见。许多病例未被发现，因为胸主动脉瘤（TAA）通常无症状，直到发生主动脉夹层或破裂等并发症。目前，TAA破裂可能性和夹层风险的临床评估以及因此的介入治疗计划主要基于最大直径和生长速率。生长速率是根据两个后续时间点的最大直径测量值计算得出的；然而，这一指标无法反映血管壁形态的复杂变化以及构成TAA强烈区域异质性基础的局部薄弱区域。由于开放手术和血管腔内修复都存在高风险，只有当主动脉破裂或夹层风险超过介入风险时，干预才是合理的。因此，TAA的临床管理仍然是一项挑战，需要新的方法来更好地识别适合择期修复的患者。我们回顾了TAA的病理生理学以及机械应力和数学生长模型在TAA管理中的作用；作为概念验证，我们将多尺度生物力学分析应用于一个TAA病例研究。
