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

ObjectivesTo test a strategy for minimizing ischemic spinal cord injury after extensive thoracoabdominal aneurysm (TAAA) repair, we occluded a small number of segmental arteries (SAs) endovascularly 1 week before simulated aneurysm repair in an experimental model.MethodsThirty juvenile Yorkshire pigs (25.2 ± 1.7 kg) were randomized into 3 groups. All SAs, both intercostal and lumbar, were killed by a combination of surgical ligation of the lumbar SAs and occlusion of intercostal SAs with thoracic endovascular stent grafting. Seven to 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 SAs 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 death, each segment of spinal cord was graded histologically using the 9-point Kleinman score (0 = normal, 8 = complete necrosis).ResultsHind limb function remained normal after coil embolization. After simulated TAAA repair, paraplegia occurred in 6 of 10 control pigs, but in only 2 of 10 pigs in group 1; no pigs in group 2 had a spinal cord injury. Tarlov scores were significantly better in group 2 (control vs group 1, P = .06; control vs group 2, P = .0002; group 1 vs group 2, P = .05). A dramatic reduction in histologic damage, most prominently in the coiled region, was seen when SAs were embolized before simulated TAAA repair.ConclusionsEndovascular coiling of 2 to 4 SAs prevented paraplegia in an experimental model of extensive hybrid TAAA repair, and helped protect the spinal cord from ischemic histopathologic injury. A clinical trial in a selected patient population at high risk for postoperative spinal cord injury may be appropriate

Subject characteristics.

<p>Subject characteristics.</p

Age and contributions of step length and cadence change to increased ambulation speed.

<p>Contributions of step length (CSL, ΔSL/ΔSP) and cadence (CCAD, ΔCAD/ΔSP) to speed (SP) increase, as a function of age in all controls (A) and age-matched controls (B).</p

Mean ambulation characteristics in all subjects groups.

<p>Results expressed in mean±SEM, as absolute values of speed, step length and cadence (A), and percent change in parameters from free to fast speed (B). ***, <i>p</i> < 0.001, **, <i>p</i> < 0.01 (pairwise comparisons, ANOVA).</p

Contributions of step length and cadence change to increased ambulation speed <i>vs</i> age or time since diagnosis in patients with PD.

<p>Contributions of step length (CSL) and cadence (CCAD) to speed increase as a function of age (A) and time since diagnosis (B). Step length Index (SLI) as a function of age (C), and time since diagnosis (D).</p

Ambulation task.

<p>each trial started with subjects in the sitting position in a first chair, from which they stood up, walked 5 m to a second chair, turned 180° before sitting in the second chair, stood up again, walked 5 m back to the starting point, turned 180° and then sat down in the first chair.</p