Department of Radiology and Center for Endovascular Therapy, Kobe University Graduate School of Medicine, Kobe, Japan.
J Vasc Surg. 2012 May;55(5):1410-8. doi: 10.1016/j.jvs.2011.10.088. Epub 2012 Jan 5.
Creating an experimental model of a type B aortic dissection with a minimally invasive endovascular procedure in swine to help future evaluation of therapies for aortic dissection.
Aortic dissection was created in 14 swine using endovascular procedures only. Under fluoroscopy, a modified 10F outer catheter with a 14 G stiffening inner metallic cannula was forced via the femoral artery into the aortic vessel wall to create an initial dissection. A .035-inch guidewire and a 4F straight catheter were advanced into the dissected space, and the dissection was extended in a retrograde direction using a technique including loop formation of the guidewire, which was placed carefully against the transmural penetration and extended as far as possible in the descending thoracic aorta up to the point where loop formation of the guidewire reached smoothly. An 8F introducer sheath was advanced with a Brockenbrough needle into the dissected space, and a proximal fenestration was created by puncturing the intima. If required, balloon dilatation was performed to enlarge the proximal and distal tears. Aortography and contrast-enhanced cone beam computed tomography (CBCT) were performed in addition to a detailed histologic evaluation of the dissected portion.
Aortic dissection was successfully created in 11 of the 14 swine (78.6%). Among the 11 dissections, nine were located in the thoracoabdominal aorta and two in the abdominal aorta. The initial aortic diameter at the middle portion of the created dissection ranged from 7.4 to 16.8 mm (mean ± standard deviation, 10.9 ± 2.9), while after dissection, it ranged from 7.8 to 19.3 mm (12.9 ± 3.8 mm). The dissected length ranged from 4.4 to 17.7 cm (10.7 ± 4.6 cm). Aortography and CBCT revealed seven dissections (63.6%) with a smooth and patent false lumen. Histologic evaluation revealed that the outer one-third of the media was separated from the inner two-thirds. In the remaining four dissections (36.4%), imaging procedures revealed the formation of a rough and patent false lumen beside the true lumen, and histologic evaluation revealed greater separation of the outer media. Five animals were chronic dissection models. Three (60%) of these survived for more than 14 days without any symptoms. Moreover, completely patent true and false lumens without thrombus formation were observed in these three animals. The aortic diameter at the dissected portion tended to be dilated compared with the initial diameter.
This new technique of creating an experimental aortic dissection model in swine is promising and should contribute to the development of future therapies for aortic dissection.
通过微创血管内手术在猪体内建立 B 型主动脉夹层的实验模型，以帮助未来评估主动脉夹层的治疗方法。
在 14 头猪中仅使用血管内手术来建立主动脉夹层。在透视下，将带有 14 G 加固内金属套管的改良 10F 外导管经股动脉强行插入主动脉血管壁，以形成初始夹层。将.035 英寸导丝和 4F 直管推进到夹层空间，通过包括导丝环形成在内的技术将夹层向逆行方向扩展，该技术小心地将导丝放置在穿透壁处，并尽可能地在降胸主动脉中向导丝环形成的顺畅点延伸。将 8F 导入鞘通过 Brockenbrough 针推进到夹层空间中，并通过刺穿内膜在近端形成一个小窗。如果需要，可进行球囊扩张以扩大近端和远端撕裂。除了对夹层部分进行详细的组织学评估外，还进行了主动脉造影和对比增强锥形束 CT（CBCT）。
在 14 头猪中成功建立了 11 个（78.6%）主动脉夹层。在 11 个夹层中，9 个位于胸主动脉和腹主动脉，2 个位于腹主动脉。创建的夹层中间部分的初始主动脉直径为 7.4 至 16.8 毫米（平均值±标准差，10.9±2.9），而夹层后为 7.8 至 19.3 毫米（12.9±3.8 毫米）。夹层长度为 4.4 至 17.7 厘米（10.7±4.6 厘米）。主动脉造影和 CBCT 显示 7 个（63.6%）夹层具有平滑且通畅的假腔。组织学评估显示，中膜的外三分之一与内三分之二分离。在其余 4 个夹层（36.4%）中，影像学检查显示在真腔旁边形成了粗糙且通畅的假腔，组织学评估显示中膜的外膜分离更大。5 头动物为慢性夹层模型。其中 3 头（60%）无任何症状存活超过 14 天。此外，这 3 只动物的真腔和假腔均完全通畅且无血栓形成。夹层部位的主动脉直径与初始直径相比有扩张趋势。
在猪体内建立实验性主动脉夹层模型的这项新技术很有前景，应有助于未来主动脉夹层治疗方法的发展。
