Endovascular coil embolization of segmental arteries prevents paraplegia after subsequent thoracoabdominal aneurysm repair: An experimental model

Abstract

Objective To test a strategy for minimizing ischemic spinal cord injury (SCI) following extensive thoracoabdominal aneurysm (TAAA) repair, we occluded a small number of segmental arteries (SAs) endovascularly one week before simulated aneurysm repair in an experimental model. Methods 30 juvenile Yorkshire pigs (25.2±1.7kg) were randomized into three groups. All SAs—intercostal and lumbar—were sacrificed by a combination of surgical ligation of the lumbar SAs and occlusion of intercostal SAs with thoracic endovascular stent grafting (TEVAR). 7–10 days before this simulated TAAA replacement, SAs in the lower thoracic/upper lumbar region were occluded using embolization coils: 1.5±0.5 SAs in Group 1 (T13/L1), and 4.5±0.5 in Group 2 (T11-L3). No SAs were coiled in the controls. Hind limb function was evaluated blindly from daily videotapes using a modified Tarlov score: 0=paraplegia; 9=full recovery. After sacrifice, each segment of spinal cord was graded histologically using the 9-point Kleinman score: 0=normal, 8=complete necrosis. Results Hind limb function remained normal after coil embolization. After simulated TAAA repair, paraplegia occurred in 6/10 control pigs, but only 2/10 pigs in Group 1: no pigs in Group 2 had SCI. Tarlov scores were significantly better in Group 2 (Control vs 1 p=0.06; Control vs 2 p= 0.0002; 1 vs 2 p=0.05). A dramatic reduction in histologic damage—most prominently in the coiled region—was seen when SAs were embolized before simulated TAAA repair. Conclusions Endovascular coiling of 2–4 SAs prevents paraplegia in an experimental model of extensive hybrid TAAA repair, and helps protect the spinal cord from ischemic histopathological injury. A clinical trial in a selected patient population at high risk for postoperative SCI may be appropriate.

Complete Entry and Re-entry Neutralization protocol in endovascular treatment of aortic dissection

“…Covering the thoracic, abdominal and infra-renal aorta with stent-grafts (during BEVAR, FEVAR) is sometimes too extensive and could lead to paraplegia due to spinal cord ischemia (Scali et al, 2013;Spear et al, 2018). Therefore, staging and other less invasive options are advised (Geisbüsch et al, 2014). Leaving the distal re-entry tear uncovered seems to protect the spinal cord perfusion, however this may eventually lead to further aortic degeneration (25-40% during first 5 years) (Hollier et al, 1988;Sailer et al, 2017).…”

Staged procedures for prevention of spinal cord ischemia in endovascular aortic surgery

“…Minimally invasive segmental artery coil embolization (MISACE) is a method first published in 2014 [12, 13] in which segmental arteries are selectively embolized and thus occluded in a preliminary, minimally invasive procedure in order to mobilize arterial collateral circulation and promote angiogenesis for spinal cord perfusion (Fig. 5).…”

Spinal cord protection in surgical and endovascular repair of thoracoabdominal aortic disease

“…We thus undertook to see whether one could provoke the changes in the collateral network that occur after the first stage of a 2-stage protocol by electively occluding a few segmental arteries 1 week before extensive segmental artery sacrifice using endovascular coils. 23 In this experimental protocol, 3 groups of 10 pigs each underwent surgical ligation of the lumbar arteries followed by FIGURE 1. Acrylic casts of the collateral network available for spinal cord perfusion in a pig.…”