Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA.
Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
Med Biol Eng Comput. 2019 Sep;57(9):1861-1874. doi: 10.1007/s11517-019-01997-w. Epub 2019 Jun 17.
Aortic dissections are challenging for it remains perplexing to determine when surgical, endovascular, or medical therapies are optimal. We studied the effect of the multilayer flow modulator (MFM) device in patients with different forms of type-B aortic dissections. CT scans were performed pre-, immediately post-MFM implantation, and multiple times within a 24-month follow-up. Three-dimensional reconstructions were created from these scans and the multilayer or single-layer mesh device placed virtually into the true lumen. We observed that MFM device can sufficiently restore flow perfusion, reduce the false lumen, eliminate local flow recirculation, and reduce wall shear stress distribution globally. Single-layer devices can reduce false lumen dimensions; however, they generate local disturbance and recirculation zones in selected areas at specific time points. Moreover, in polar extremes of dissection, the MFM device restored flow to vital organs perfusing vessels independent of effects on luminal patency. Management of aortic dissections should focus on modulation of blood flow, suppression of local recirculation, and restoration of vital organ perfusion rather than primarily restoring vascular lumen morphology. While the latter restores the geometry of the true lumen, only the former restores homeostasis. Graphical abstract.
主动脉夹层的治疗颇具挑战性,因为目前仍难以确定何时采用手术、血管内或药物治疗最为理想。我们研究了多层流调节装置(MFM)在不同类型 B 型主动脉夹层患者中的作用。在 MFM 植入前、植入即刻以及 24 个月的随访中多次进行 CT 扫描。从这些扫描中创建三维重建,并将多层或单层网片装置虚拟置于真腔中。我们观察到,MFM 装置可充分恢复血流灌注,减少假腔,消除局部血流再循环,并减少全局壁面切应力分布。单层装置可减小假腔尺寸;然而,它们在特定时间点的特定区域会产生局部干扰和再循环区。此外,在夹层的极极端情况下,MFM 装置可恢复向重要器官供血的血管的血流,而不受管腔通畅性影响。主动脉夹层的治疗应侧重于调节血流、抑制局部再循环和恢复重要器官灌注,而不仅仅是恢复血管腔形态。虽然后者恢复了真腔的几何形状,但只有前者恢复了体内平衡。示意图。