Department of Cardiac Surgery, University of Michigan, Ann Arbor, MI, USA.
Department of Surgery, University of Michigan, Ann Arbor, MI, USA.
Eur J Cardiothorac Surg. 2020 Jun 1;57(6):1061-1067. doi: 10.1093/ejcts/ezz381.
Maximal aortic diameter is commonly used to assess aortic risk but poorly predicts the timing and location of dissection events in patients with connective tissue disease who undergo regular imaging surveillance. Hence, we aimed to use available surveillance computed tomography angiography (CTA) scans to investigate the correlation between 3-dimensional (3D) growth and cyclic transmural wall stress with the location of intimal tear formation.
Three type B aortic dissection patients with 2 available electrocardiogram (ECG)-gated pre-dissection CTA scans and without surgical repair during the pre-dissection interval were retrospectively identified at our institution. Vascular deformation mapping was used to measure 3D aortic growth between 2 pre-dissection clinical CTA studies. In addition, we performed a computational analysis to estimate cyclic transmural wall stress in patient-specific baseline CTA geometries.
In all 3 connective tissue disease patients, the site of type B aortic intimal tear co-localized with areas of peak 3D aortic wall growth. Aortic growth was detected by clinical radiological assessment in only 1 case. Co-localization of peak transmural stress and the site of intimal tear formation were found in all cases.
Focal areas of growth and transmural wall stress co-localized with the site of intimal tear formation. These hypothesis-generating results suggest a possible new analytic pathway for a more sophisticated assessment of the factors leading to the initiation of dissection in patients with connective tissue disease. These methods could improve on current risk-stratification techniques.
最大主动脉直径常用于评估主动脉风险，但在接受定期影像学监测的结缔组织疾病患者中，其对夹层事件的时间和位置的预测能力较差。因此，我们旨在使用现有的监测计算机断层血管造影（CTA）扫描来研究 3 维（3D）生长和循环壁内应力与内膜撕裂形成位置之间的相关性。
本研究回顾性分析了我院 3 例 B 型主动脉夹层患者，这些患者在夹层前有 2 次可用的心电图（ECG）门控前夹层 CTA 扫描，且在夹层前间隔内无手术修复。使用血管变形映射来测量 2 次前夹层临床 CTA 研究之间的 3D 主动脉生长。此外，我们还进行了计算分析，以估计患者特定基线 CTA 几何形状中的循环壁内应力。
在所有 3 例结缔组织疾病患者中，B 型主动脉内膜撕裂的部位与 3D 主动脉壁生长的峰值部位一致。仅在 1 例中通过临床影像学评估检测到主动脉生长。所有病例均发现峰值壁内应力和内膜撕裂形成部位的共定位。
生长和壁内应力的局部区域与内膜撕裂形成的部位共定位。这些假设生成的结果表明，对于结缔组织疾病患者，可能存在一种新的分析途径，可以更深入地评估导致夹层发生的因素。这些方法可以改进当前的风险分层技术。
