Spinal cord injury after thoracic endovascular aortic aneurysm repair

A dedicated preventive protocol sustainably avoids spinal cord ischemia after endovascular aortic repair

Objective

To analyze the incidence of spinal cord ischemia (SCI) after complex endovascular aortic repair (EVAR) after the introduction of a dedicated SCI preventive protocol.

Methods

Retrospective review of all consecutive patients undergoing complex EVAR with branched (BEVAR) and/or fenestrated grafts (FEVAR) during a 6-year period starting January 1st, 2015. The preventive protocol consisted of staging extensive aortic repairs, maintaining a mean arterial pressure (MAP) >80 mm Hg, Hb level >110 g/L, early lower limb reperfusion and neurological control per hour during the post-operative stay in the intensive care unit (36-72 h). Prophylactic cerebrospinal fluid drainage (CSFD) was used selectively. Pre- intra-, and 30-day postoperative clinical data and imaging were collected. Primary end point was the development of perioperative SCI. Secondary outcome included technical and clinical success.

Results

Complex EVAR was performed in 205 patients (167 males, 72 (67-75) years, 182 (88.8%) elective) with juxtarenal aneurysms (JRA, 155 patients) or thoracoabdominal aortic aneurysms (TAAA). SCI occurred after JRA repair in two patients (1.3%, both ruptures) and after TAAA repair in three (6.0%, one rupture) (p = 0.06), all within 9 h postoperatively. There was symptom regression in three cases (one partial, two complete), resulting in a persistent SCI level of 0.6% and 4.0% for JRA and TAAA, respectively. Only one patient with persistent SCI could be discharged from the hospital alive. Patients developing SCI were more commonly female (n = 3, p = .016), presented with rupture (n = 3, p < .001), had preoperative renal insufficiency (n = 5, p < .001) and had lower minimal MAP (p = .015). No regression analysis was done due to the limited number of SCI events in relation to the study population size. Primary technical success was achieved in 162 patients (83.5%) and clinical success in 153 patients (75.4%), without any differences between the groups.

Conclusions

The incidence of persistent SCI after complex EVAR is low with the use of a dedicated SCI preventive protocol allowing the early diagnosis. Females, patients with ruptured aneurysms and preoperative renal insufficiency are at higher risk. Further studies are needed to customize the protocols particularly in those high-risk patients.

Readmissions Following Endovascular Thoracic and Thoracoabdominal Aortic Repairs in the Vascular Implant Surveillance and Interventional Outcomes Network (VISION)

BACKGROUND

Investigate readmission rates, diagnoses associated with readmission, and associations with mortality through 90 days postoperatively after elective endovascular thoracic and thoracoabdominal aortic repair overall and by extent of coverage.

METHODS

A cohort of index elective nontraumatic endovascular thoracic and thoracoabdominal aortic cases from 2010 to 2018 was derived from the Vascular Implant Surveillance and Interventional Outcomes Network. Cohort readmissions within 90 days postoperative were examined both overall and by Crawford extent (CE) of aortic coverage. Postoperative mortality was examined by reason for readmission and CE.

RESULTS

The cohort consisted of 2,105 patients who underwent endovascular thoracic and thoracoabdominal aortic repair (1,550 CE 0A/0B; 242 CE 1-3; 313 CE 4-5). Cumulative risk for 90-day readmission was 34.3% in CE 0A/0B repairs, 33.4% in CE 4-5 repairs, and 47.4% in CE 1-3 repairs. Compared with CE 0A/B, patients with CE 1-3 repairs experienced an increased risk of readmission within 90 days postoperatively after adjusting for preoperative factors (adjusted hazard ratio [HR] 1.27 [1.00, 1.61]), while the readmission risk for CE 4-5 repairs did not differ significantly (adjusted HR 0.83 [0.64, 1.06]). Significant risk factors for 90-day readmission included chronic obstructive pulmonary disease, dialysis dependence, limited ambulation, visceral/spinal ischemia, and in-hospital stroke. Discharge to home was protective against readmission (HR 0.65, confidence interval 0.54-0.79). Patients with a readmission within 90 days had a 7.89-fold increase in 90-day mortality (HR 7.84; 5.17, 11.9) compared with those not readmitted.

CONCLUSIONS

Increasing extent of endovascular thoracic and thoracoabdominal aortic repair was associated with higher 90-day readmission rates. Readmission for all CE was associated with near 8-fold increased risk of mortality. Risk factors associated with increased risk for readmission included pulmonary insufficiency, renal disease, and poor functional status. These findings can inform stakeholders about investment of resources to improve processes of care that both target prevention and mitigate risk of readmission after elective endovascular thoracic and thoracoabdominal aortic repair.

Treatment for Stanford type B aortic dissection with insufficient anchoring region using castor integrated branched aortic stent graft

Background

To investigate the clinical efficacy of Castor integrated branched aortic stent graft for the treatment of Stanford type B aortic dissection with insufficient anchoring area.

Methods

Retrospective analysis of clinical data of 26 patients with Stanford type B aortic dissection with insufficient anchoring region (<15 mm) treated by Castor branched aortic stent graft from September 2018 to June 2022 at Ganzhou People's Hospital, including 23 acute cases and 3 chronic cases.

Results

Surgical procedures were successfully performed in all 26 patients, and during the perioperative period no complications occurred, such as cerebrovascular accident, stenosis or occlusion of left subclavian artery, progression of reverse avulsion of aortic dissection, and paraplegia. During the operation 2 patients had a small amount of type I endoleak, which disappeared during the postoperative follow-up. The other patients had good postoperative follow-up results. Review of the aortic CTA indicated good stent morphology with patency of the left subclavian artery.

Conclusions

The Castor integrated branched aortic stent graft expanded the indications for endoluminal treatment for Stanford type B aortic dissection, which can avoid open surgery and has good clinical outcomes.

Use of Spinal Anesthesia during Thoracic Endovascular Aortic Repair

BACKGROUND

The purpose of this study was to assess outcomes after spinal anesthesia (SA) versus general anesthesia (GA) in patients undergoing thoracic endograft placement and to evaluate the adjunctive use of cerebrospinal fluid drainage (CSFD) placement.

METHODS

A single-center retrospective review of patients that underwent thoracic endograft placement from 2001 to 2019 was performed. Patients were stratified based on the type of anesthesia they received: GA, SA or epidural, GA with CSFD, and SA with CSFD. Primary outcomes included 30-day mortality and length of stay (LOS). Baseline characteristics were analyzed with Student's t-test and Pearson's chi-squared test. Multivariate logistic regression analysis was performed to identify risk factors for 30-day mortality and longer LOS.

RESULTS

A total of 333 patients underwent thoracic endograft placement; 104 patients received SA, 180 patients received GA, 30 patients received GA and CSFD, and 19 patients received SA and CSFD. Of the total patients, 16.2% underwent thoracic endograft placement for type B aortic dissection, 3.3% for type A aortic dissection, and 12.3% for penetrating ulcer. The mean age of the study population was 68.7 years old. Patients undergoing SA were older with a mean age of 73.4 years versus 64.7 years for patients undergoing GA (P < 0.001). Spinal anesthesia (SA) was preferred in patients at high risk for GA (>75 years old: 52.9% vs. 33.3%, P < 0.001; renal comorbidities: 20.6% vs. 10.6%, P = 0.03, and current smokers: 26.7% vs. 9.6%, P < 0.001). Length of stay (LOS) was decreased in the SA group (4.29 days vs. 9.70 days, P < 0.001). There was a lower incidence of spinal cord ischemia in the SA group (1.0% vs. 2.2%, P = 0.44), as well as significantly decreased 30-day mortality (0% vs. 5.6%, P = 0.01), reintervention (19.2% vs. 26.8%, P = 0.02), and return to the operating room (6.8% vs. 12.7%, P = 0.02). Of the 19 patients that had SA + CSFD, there were no signs and symptoms of spinal cord ischemia and decreased incidence of perioperative complications (0% vs. 33.3%, P = 0.01). There was no difference in the risk for intraoperative complications, neurologic complications, or 30-day mortality between GA + CSFD patients versus SA + CSFD patients. Age >75 (P = 0.002), intraoperative complications (P < 0.001), and perioperative complications (P = 0.02) were associated with increased mortality after thoracic endograft placement per multivariate logistic regression analysis.

CONCLUSIONS

Spinal anesthesia (SA) in select high-risk patients was associated with reduced 30-day mortality, neurologic complications, and LOS compared to GA. The concurrent use of spinal drainage and SA had satisfactory results compared to spinal drainage and GA.

Preoperative Spinal Arterial Supply Mapping Using Non-Selective Cone Beam Computed Tomography before Complex Aortic Repair

Pre-op spinal arterial mapping is crucial for complex aortic repair. This study explores the utility of non-selective cone beam computed tomography (CBCT) for pre-operative spinal arterial mapping to identify the Adamkiewicz artery (AKA) in patients undergoing open or endovascular repair of the descending thoracic or thoracoabdominal aorta at risk of spinal cord ischemia. Pre-operative non-selective dual-phase CBCT after intra-aortic contrast injection was performed in the aortic segment to be treated. The origin of detected AKA was assessed based on image fusion between CBCT and pre-interventional computed tomography angiography. Then, the CBCT findings were compared with the incidence of postoperative spinal cord ischemia (SCI). Among 21 included patients (median age: 68 years, 20 men), AKA was detected in 67% within the explored field of view, predominantly from T7 to L1 intercostal and lumbar arteries. SCI occurred in 14%, but none when AKA was not detected (p < 0.01). Non-selective CBCT for AKA mapping is deemed safe and feasible, with potential predictive value for post-surgical spinal cord ischemia risk. The study concludes that non-selective aortic CBCT is a safe and feasible method for spinal arterial mapping, providing promising insights into predicting post-surgical SCI risk.

Recognition of Significantly Delayed Spinal Cord Ischemia Following Thoracic Endovascular Aortic Repair: A Case Report and Review of the Literature

Spinal cord ischemia (SCI) is an uncommon but serious complication of thoracic endovascular aortic repair (TEVAR). SCI after TEVAR is thought to result from decreased segmental blood supply to an important network of collateral blood flow in the spinal cord. Little is known about the prevalence and optimal treatment of SCI that occurs beyond the periprocedural period. We report a case of delayed SCI in a 67-year-old patient who underwent TEVAR. The patient presented almost two years after TEVAR with acute paraplegia preceded by pre-syncope. The delayed SCI was likely triggered by pre-syncope, a thrombosed endoleak shown on imaging, and the patient's vascular risk factors. Treatments included cerebrospinal fluid (CSF) drainage, mean arterial pressure (MAP) augmentation, and a naloxone infusion, which resulted in moderate recovery in lower extremity motor function. This case highlights the tenuous nature of spinal cord perfusion after TEVAR and that prompt recognition and early treatment of SCI are critical in preventing the progression from ischemia to infarction.

Risk Factors for Spinal Cord Injury during Endovascular Repair of Thoracoabdominal Aneurysm: Review of the Literature and Proposal of a Prognostic Score

Despite recent improvements, spinal cord ischemia remains the most feared and dramatic complication following extensive aortic repair. Although endovascular procedures are associated with a lower risk compared with open procedures, this risk is still significant and must be considered. A combined medical and surgical approach may help to optimize the tolerance of the spinal cord to ischemia. The aim of this review is to describe the underlying mechanism involved in spinal cord injury during extensive endovascular aortic repair, to describe the different techniques used to improve spinal cord tolerance to ischemia-including the prophylactic or curative use of spinal drainage-and to propose our algorithm for spinal cord protection and the rational use of spinal drainage.

Spinal cord ischemia rates and prophylactic spinal drainage in patients treated with fenestrated/branched endovascular repair for thoracoabdominal aneurysms

OBJECTIVE

Spinal cord ischemia (SCI) is a devastating complication after thoracoabdominal aortic aneurysm (TAAA) repair. The benefit of prophylactic cerebrospinal fluid drainage (pCSFD) to prevent SCI is still under investigation. The aim of this study was to evaluate the SCI rate and the impact of pCSFD following complex endovascular repair (fenestrated or branched endovascular repair [F/BEVAR]) for type I to IV TAAA.

METHODS

The STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) statement was followed. A single-center retrospective study was conducted, including all consecutive patients, managed for TAAA type I to IV using F/BEVAR, between January 1, 2018, and November 1, 2022, for degenerative and post-dissection aneurysms. Patients with juxta- or pararenal aneurysms were excluded, as well as cases managed urgently for aortic rupture or acute dissection. After 2020, pCSFD in type I to III TAAAs was abandoned and replaced by therapeutic CSFD (tCSFD), performed only in patients presenting SCI. The primary outcome was the perioperative SCI rate for the entire cohort and the role of pCSFD for type I to III TAAAs.

RESULTS

In total, 198 patients were included (mean age, 71.1±3.4 years; 81.8% males), including 50.5% with type I to III TAAA. The primary technical success was 94.9%. The perioperative mortality was 2.5%. and the major adverse cardiovascular event (MACE) rate was 10.6%; 4.5% presented SCI of any type (2.5% paraplegia). When comparing the SCI group with the remaining cohort, patients with SCI presented higher MACE (66.7% vs 7.9%; P < .001) rate and longer intensive care unit stay (3.5 vs 1 day; P = .002). Following type I to III repair, similar SCI, paraplegia, and paraplegia with no recovery rates were reported in the pCSFD and tCSFD groups (7.3% vs 5.1%; P = .66; 4.8% vs 3.3%; P = .72; and 2% vs 0%; P = .37).

CONCLUSIONS

The incidence of SCI after TAAA I to IV endovascular repair was low. SCI was associated with significantly increased MACE and intensive care unit stay. The prophylactic use of CSFD in type I to III TAAAs was not associated with lower SCI rates and may not be justified routinely.

Thoracic endovascular aortic repair of metachronous thoracic aortic aneurysms following prior infrarenal abdominal aortic aneurysm repair

OBJECTIVE

Thoracic endovascular aortic repair (TEVAR) of metachronous thoracic aortic aneurysms (M-TAAs) following previous infrarenal abdominal aortic aneurysm (AAA) repair has been associated with higher spinal cord ischemia (SCI) risk compared with TEVAR of primary thoracic aortic aneurysms (TAAs). However, data on the impact of the type of prior infrarenal aortic repair on outcomes are scarce. In this study, we examined perioperative outcomes and long-term mortality following TEVAR M-TAA compared with primary TEVAR of TAA.

METHODS

We identified all Vascular Quality Initiative (VQI) patients who underwent TEVAR of TAA in the descending thoracic aorta from 2013 to 2022. Only patients undergoing primary TEVAR or TEVAR following infrarenal open (OAR) or endovascular (EVAR) repair were included. We performed univariate analyses to identify differences in baseline and procedural characteristics, and multivariable analyses for perioperative outcomes and 5-year mortality using logistic and Cox regression, respectively.

RESULTS

We included 1493 patients who underwent primary TEVAR (81%) or TEVAR following prior OAR (9.0%) or prior EVAR (9.7%). Compared with primary TEVAR, patients undergoing TEVAR M-TAA were older, more commonly male, white, and had higher rates of hypertension, smoking, and renal dysfunction. Patients with M-TAA were more likely to be asymptomatic and have larger diameters at presentation but were exposed to greater contrast volume and procedural times relative to primary TEVAR patients. Following risk-adjustment, compared with primary TEVAR, TEVAR after prior EVAR was associated with higher perioperative mortality (9.7% vs 3.9%; odds ratio [OR], 5.3; 95% confidence interval [CI], 2.3-12; P < .001) and 5-year mortality (40% vs 24%; hazard ratio [HR], 2.1; 95% CI, 1.4-3.1; P = .001). Specifically, among octogenarians (n = 375; 25%), the perioperative and 5-year mortality differences were even more pronounced (perioperative mortality: 17% vs 8.4%; OR, 6.7; 95% CI, 2.2-21; P = .001; 5-year mortality: 50% vs 27%; HR, 3.0; 95% CI, 1.5-5.7; P = .010). However, in-hospital complications, including SCI (2.6% vs 2.8%; OR, 1.2; 95% CI, 0.33-3.3; P = .77), were not notably different. In contrast, TEVAR after previous OAR was associated with comparable perioperative mortality (4.4% vs 3.9%; OR, 1.2; 95% CI, 0.32-3.8; P = .73), 5-year mortality (28% vs 24%; HR, 1.3; 95% CI, 0.80-2.1; P = .54), and in-hospital complications, including SCI (2.6% vs 0.7%; OR, 0.21; 95% CI, 0.01-1.1; P = .16).

CONCLUSIONS

Patients undergoing TEVAR of M-TAAs after prior EVAR, particularly octogenarians, have higher perioperative and 5-year mortality and therefore, represent a high-risk group. Future efforts should strive to discern the underlying factors leading to these poorer outcomes; meanwhile, these findings emphasize the need for careful patient selection and appropriate preoperative counseling in these high-risk individuals.

Anesthesia management of patients undergoing thoracic endovascular aortic repair: A retrospective analysis of single center

Thoracic endovascular aortic repair (TEVAR) is a new alternative surgical treatment for aortic pathologies, which is more minimally invasive. The aim of current study was to summarize the single-center experience of general anesthesia for patients undergoing TEVAR. In adult patients undergoing surgery for congenital heart disease, the strategy of "fast-track" anesthesia with early extubation in theater is associated with a shorter intensive care unit (ICU) stay, and lower health-care-related costs. Fast-track anesthesia has not been assessed in patients under TEVAR. Adult patients who received general anesthesia for TEVAR in our center from January 2020 to December 2020 were included. Baseline characteristics, airway management, anesthetic techniques and major complications were collected. A total of 204 (171 male, mean age 58.1 ± 11.5 years) patients met inclusion criteria for this study. The distribution of pathologies included 29 descending thoracic aneurysms, 87 type B dissections, and 88 intramural hematoma/perforating aortic ulcer. Etomidate was the induction agent in 190 (93.1%) patients, compared with propofol in 16 (7.8%). Cisatracurium was the muscle relaxant in 201 (98.5%), compared with rocuronium in 3 (1.5%). Midazolam (benzodiazepines) was given to 124 (60.8%) patients during anesthesia induction. General anesthesia was maintained with sevoflurane in 85.3% (174) patients, dexmedetomidine in 201 (98.5%) and propofol in 204 (100%). Postoperative length of stay (LOS) in the hospital was 6.0 (5.0-7.8) days. LOS in the ICU was 23.0 (20.0-27.8) hours. Overall neurologic event rate was 2.0% (n = 4) (spinal cord ischemia 1.5% [n = 3]; stroke 0.5% [n = 1]). After matching, patients who received "fast-track" anesthesia had a shorter LOS in ICUs (21.0 [18.0-24.0] vs 24.0 [20.0-44.0] hours; P = .005), and a shorter postoperative LOS in hospital (5.0 [4.0-7.0] vs 6.0 [5.0-8.0] days; P = .001). There were no in-hospital deaths. Fast-track anesthesia is feasible and safe in patients underwent TEVAR. This management strategy is associated with shorter LOS of ICU and total postoperative hospital stays. An early extubation strategy should be implemented for hemodynamically stable patients.

The fate of spinal arteries after the stent-assisted balloon-induced intimal disruption and relamination in aortic dissection repair technique: a case series

Objective

We evaluated the patency of the spinal arteries (intercostal and lumbar) after the STABILISE (stent-assisted balloon-induced intimal disruption and relamination in aortic dissection repair) technique.

Methods

A retrospective analysis of all patients with aortic dissection treated with the STABILISE technique between April 2018 and July 2021 was performed. Imaging analysis of the spinal cord vascular supply was accomplished using multiplanar and maximum intensity projection reconstructed images of pre- and postoperative computed tomography angiograms at 1 month, 12 months, and annually thereafter.

Results

Twelve patients were treated for complicated aortic dissection. Primary technical success was 100% and mid-term clinical success, at a mean follow-up of 27 ± 12 months, was 90%. No cases of spinal cord ischemia were identified. One patient died after 1 year (non-aortic related), and one patient was lost to follow-up. A significant decrease was found in the mean number of patent spinal arteries in the stent graft area at 1 month (P < .001), 1 year (P < .001), and 2 years (P = .004). However, no significant reduction was found in the number of spinal arteries in either the bare metal stented or nonstented aorta (P > .05).

Conclusions

Use of the STABILISE technique decreased intercostal artery patency in the thoracic stent graft area, but spinal artery patency was not significantly affected by the bare metal stent nor its aggressive ballooning. These findings constitute a step toward a better understanding of the safety of this technique.

Biomarkers of Spinal Cord Injury in Patients Undergoing Complex Endovascular Aortic Repair Procedures-A Narrative Review of Current Literature

Complex endovascular aortic repair (coEVAR) of thoracoabdominal aortic aneurysms (TAAA) has greatly evolved in the past decades. Despite substantial improvements of postoperative care, spinal cord injury (SCI) remains the most devastating complication of coEVAR being associated with impaired patient outcome and having an impact on long-term survival. The rising number of challenges of coEVAR, essentially associated with an extensive coverage of critical blood vessels supplying the spinal cord, resulted in the implementation of dedicated SCI prevention protocols. In addition to maintenance of adequate spinal cord perfusion pressure (SCPP), early detection of SCI plays an integral role in intra- and postoperative patient care. However, this is challenging due to difficulties with clinical neurological examinations during patient sedation in the postoperative setting. There is a rising amount of evidence, suggesting that subclinical forms of SCI might be accompanied by an elevation of biochemical markers, specific to neuronal tissue damage. Addressing this hypothesis, several studies have attempted to assess the potential of selected biomarkers with regard to early SCI diagnosis. In this review, we discuss biomarkers measured in patients undergoing coEVAR. Once validated in future prospective clinical studies, biomarkers of neuronal tissue damage may potentially add to the armamentarium of modalities for early SCI diagnosis and risk stratification.

Risk Factors Associated with Spinal Cord Ischemia During Aortic Aneurysm Repair

BACKGROUND

The risk of spinal cord ischemia (SCI) with aortic aneurysm repair can cause significant neurological morbidity. Prevention of SCI is critical. We sought to identify risk factors that predispose to SCI that may guide strategies to mitigate the occurrence of SCI during and following these procedures.

METHODS

This study includes all adults who underwent atraumatic, unruptured, thoracic, and suprarenal aortic aneurysm repairs (endovascular or open) at our institution over 11 years (2010-2020). Our database included patient demographics, aneurysm anatomic features, and operative characteristics and an extreme gradient boost (XGB) machine method was used to develop a predictive model for SCI. The model was trained on an 80% randomly stratified cohort of the data and tested on the remaining 20% testing cohort. Shapley values were used to determine the most important predictive factors of SCI and decision trees were used to identify risk factor threshold values and highest risk factor combinations.

RESULTS

Information was collected for 174 adult patients undergoing thoracic and suprarenal aortic repair from 2010 to 2020. Fifty eight percent of the patients were male. Ninety seven (55.7%) patients had open aortic repair and 87 (44.3%) had endovascular repair. Twenty seven (15%) of all patients had major complications and were considered to have SCI. The XGB model converged over the training cohort with a testing cohort accuracy of 0.841 [Sensitivity = 75%, Specificity = 68%] and area under the curve of receiver operating characteristic of 0.774. The XGB model identified older age (> 65 years), history of neurologic disease, hyperlipidemia, diabetes, coronary artery disease, heart failure, poor renal function, < 6 months since last aortic repair, chronic anticoagulant use, preoperational anemia (Hemoglobin < 9), thrombocytopenia (platelet < 90,000), coagulopathy (prothrombin time > 15s and activated partial thromboplastin time > 40s), hypotension (mean arterial pressure < 70 mm Hg), longer operations (> 100 min), aneurysms longer than 5 cm, and anatomic location of aneurysm caudal to T-11 as risk factors for SCI in all types of aortic repair. Diabetic and heart failure patients undergoing longer operations (> 100 min) with thrombocytopenia or aneurysms longer than 5 cm were at the highest risk.

CONCLUSIONS

The XGB model accurately identified risk factors of SCI with aortic aneurysm repair that may guide patient selection, timing of surgery, and strategies to minimize the risk of SCI.

Spinal drain for aortic aneurysm repairs: tool or toy?

PURPOSE OF REVIEW

Spinal cord injury (SCI) is one of the biggest complications in open and endovascular aortic repairs. Historically, cerebrospinal fluid drains (CSFD) have been one of the most effective modalities in reducing SCI and one of the most studied. CSFD placement also carries its' own set of procedural risks. This editorial intends to evaluate recent literature to determine whether CSFDs remain a valuable tool in aortic repair.

RECENT FINDINGS

As the surgical management of thoracic aortic aneurysms has evolved, there has been an increasing number of endovascular repairs. Current recommendations emphasize prophylactic CSFD placement in endovascular repair cases deemed 'high risk.' However, several meta-analyses differ on whether prophylactic CSFD placement reduced the risk of SCI. The incidence of SCI decreased between 2014 and 2018, despite a similar rate of prophylactic CSFD placement suggesting other techniques are being performed and may be effective in spinal cord protection as well.

SUMMARY

There has been conflicting data on whether CSFDs have a role in reducing the risk of SCI in endovascular aortic repair. Some studies suggest that there is no benefit to placement while others suggest that routine prophylactic drains should be placed for all endovascular cases. Despite this, efforts have been made to selectively place CSFDs in those patients deemed at 'high risk' for SCI. CSFDs also remain a part of rescue treatment for postoperative SCI. This suggests that CSFDs continue to be a valuable tool that we need to better comprehend. Future research is necessary to better understand how patient risk factors can be balanced with perioperative management to help identify patients who may benefit from CSFD placement.

A Novel Bypass Technique to Prevent Vexing Spinal Cord Ischemia in Endovascular Thoracoabdominal Aortic Intervention

BACKGROUND

Spinal cord ischemia remains a devastating complication when treating patients with complex thoracoabdominal aortic aneurysms using fenestrated endovascular aortic repair. This approach is progressively deployed. However, to date, no strategy has been identified to reduce the feared risk of spinal cord ischemia.

OBJECTIVE

To introduce a novel bypass technique using a customized composite graft to create a direct extra-anatomic revascularization before fenestrated endovascular aortic repair in patients with high-risk of spinal cord ischemia.

METHODS

To demonstrate this novel concept, we present here a clinical case that reports the strategy of this novel concept in detail. An 83-year-old man with medical history of endovascular repair of an abdominal aortic aneurysm and thoracic aorta presented with a type IA endoleak, located along the posterior superior aspect of the aortic stent graft adjacent to the lumbar arteries. A multidisciplinary plan was developed, which included a novel bypass from the profunda femoris to the left L1 radicular artery before fenestrated endovascular aortic repair to prevent spinal cord ischemia.

RESULTS

The patient successfully receives the novel extra-anatomic revascularization bypass before fenestrated endovascular aortic repair. During the first implementation of this strategy, no intraoperative difficulties and postoperative complications were observed.

CONCLUSION

This case demonstrates a novel surgical technique before fenestrated endovascular aortic repair for prevention of spinal cord ischemia. In addition, this concept provides a promising direction to not only complement the existing surgical techniques but also to generate more future innovations.

Anaesthesia for vascular emergencies - a state of the art review

In this state-of-the-art review, we discuss the presenting symptoms and management strategies for vascular emergencies. Although vascular emergencies are best treated at a vascular surgical centre, patients may present to any emergency department and may require both immediate management and safe transport to a vascular centre. We describe the surgical and anaesthetic considerations for management of aortic dissection, aortic rupture, carotid endarterectomy, acute limb ischaemia and mesenteric ischaemia. Important issues to consider in aortic dissection are extent of the dissection and surgical need for bypasses in addition to endovascular repair. From an anaesthetist's perspective, aortic dissection requires infrastructure for massive transfusion, smooth management should an endovascular procedure require conversion to an open procedure, haemodynamic manipulation during stent deployment and prevention of spinal cord ischaemia. Principles in management of aortic rupture, whether open or endovascular treatment is chosen, include immediate transfer to a vascular care centre; minimising haemodynamic changes to reduce aortic shear stress; permissive hypotension in the pre-operative period; and initiation of massive transfusion protocol. Carotid endarterectomy for carotid stenosis is managed with general or regional techniques, and anaesthetists must be prepared to manage haemodynamic, neurological and airway issues peri-operatively. Acute limb ischaemia is a result of embolism, thrombosis, dissection or trauma, and may be treated with open repair or embolectomy, under either general or local anaesthesia. Due to hypercoagulability, there may be higher numbers of acutely ischaemic limbs among patients with COVID-19, which is important to consider in the current pandemic. Mesenteric ischaemia is a rare vascular emergency, but it is challenging to diagnose and associated with high morbidity and mortality. Several peri-operative issues are common to all vascular emergencies: acute renal injury; management of transfusion; need for heparinisation and reversal; and challenging postoperative care. Finally, the important development of endovascular techniques for repair in many vascular emergencies has improved care, and the availability of transoesophageal echocardiography has improved monitoring as well as aids in surgical placement of endovascular grafts and for post-procedural evaluation.

Monitoring During Vascular Surgery

Vascular surgical patients present unique challenges for anesthesiologists, because of their medical vulnerabilities as well as their tendency for rapid intraoperative hemodynamic changes. Intraoperative monitors have been used for decades to reduce adverse outcomes, improve mortality, and create optimal surgical conditions. Understanding the indications and appropriate management of monitoring modalities is essential for optimizing patient care, and preventing harm associated with misinterpretation. We aim to review monitoring technologies used in complex vascular procedures, as well as the current guidelines, clinical trial outcomes, and basic mechanisms of each monitoring modality.

Anesthetic Management for Endovascular Repair of Thoracic and Abdominal Aortic Aneurysms

Aortic aneurysms-both abdominal and thoracic-are a significant cause of death and disability in the United States. Endovascular aneurysm repair has since become the preferred operative treatment of most thoracic and abdominal aneurysms because of a lower rate of complications and better outcomes compared with the open approach. Patients who present for endovascular aneurysm repair often have comorbid conditions related to their aortic pathology. These conditions should be evaluated and optimized before the procedure.

Two-stage aortic surgery for distal aortic arch and descending aorta aneurysms: A case report

RATIONALE

Although surgical treatment strategies for patients with extensive thoracic aortic disease involving the aortic arch have improved considerably, the impact of stent graft length and placement site on aortic remodeling at long-term follow-up is not fully understood, and the protection of the Adamkiewicz artery (AKA) using the frozen elephant trunk (FET) method is also unclear.

PATIENT CONCERNS

The patient was a 69-year-old man with diabetic nephropathy who became increasingly fatigued and started maintenance hemodialysis 6 months prior to admission. At 64 years, he underwent clipping of a right cerebellar artery aneurysm. In addition, a 1.8 cm aneurysm was found in the contralateral extracranial internal carotid artery. He also had an atrial septal defect and moderate aortic regurgitation and was receiving continuous positive airway pressure therapy for sleep apnoea syndrome.

DIAGNOSIS

He had aneurysms in the aortic arch (4.8 cm in diameter) and descending aorta (6 cm in diameter), which was located at T6-9. Preoperative 3-dimensional computed tomography showed that the (AKA) bifurcated at T10-11.

INTERVENTIONS

Considering the patient's several comorbidities and frailty, we planned to perform 1-stage extended aortic arch repair using the FET procedure. However, we performed 2-stage aortic surgery to prevent spinal ischemia, anticipating substantial cardiac enlargement and blood pressure instability due to dialysis treatment. Aortic valve replacement, atrial septal defect patch closure, and aortic arch surgery were performed. A 7-cm elephant trunk was inserted in the descending aorta. Postoperatively, the patient continued rehabilitation until his blood pressure stabilized during dialysis therapy. At postoperative week 4, he underwent thoracic endovascular aortic repair for a descending aortic aneurysm.

OUTCOMES

After surgery, his physical strength decreased; however, he recovered and was discharged 1 month later without any complications. One year after the second operation, he is living a healthy life.

LESSONS

Extensive aortic arch surgery using the FET procedure is effective for distal aortic arch and descending aortic aneurysms. Nevertheless, in cases in which the position of the AKA is close to the aortic aneurysm and blood pressure control is difficult, a 2-stage procedure and accurate positioning of thoracic endovascular aortic repair are both desirable.

Comprehensive Perioperative Approach to Complex Spine Deformity Management

OBJECTIVE

Study perioperative strategies for optimizing neuroprotection in complex spine deformity correction surgery.

METHODS

We report the case of a patient with severe lumbar dextroscoliosis, thoracolumbar junction hyperkyphosis with a 40-degree Cobb angle levoconvex scoliosis who underwent spinal deformity correction with loss of neuromonitoring during surgery. We performed a literature review on perioperative management of complex spine deformity.

RESULTS

A 50-year-old man presented with lumbar pain and right L4 radiculopathy. Surgical intervention for deformity correction and decompression was indicated with T4-L4 posterior instrumentation L2/L3 and L3/L4 transforaminal lumbar interbody fusion. Surgery was aborted due to the loss of neuromonitoring. Postsurgery, the patient had left sensory deficit and the neurocritical care team clinically suspected and deduced the anatomic location of the spinal cord compression. Magnetic resonance imaging confirmed a T10-T11 hyperintensity suggestive of cord ischemia due to osteophyte compressing the spinal cord. The patient underwent a second corrective surgery with no intraoperative events and has no long-term neurological sequela.

CONCLUSIONS

This case illustrates that a comprehensive perioperative approach and individualized risk factor assessment is useful in complex spine deformity surgery. Further research is needed to determine how this individualized comprehensive approach can lead to intraoperative and postoperative countermeasures that improved spine surgery outcomes.

LEVEL OF EVIDENCE

Level V.

The Colt Device for Treating Thoraco-Abdominal Aneurysms - Concept and Clinical Results

Objective

To report results of application a new stent graft design for the treatment of patients with thoraco-abdominal aneurysms (TAAAs), which was co-invented by a vascular surgeon. This is a retrospective observational study.

Methods

The Colt is a self-expanding stent graft, composed of nitinol metal stents creating a special exoskeleton with asymmetric springs covered with polyester material. The Colt device offers some advantages over existing stent graft options. The main body is available in two different diameters on both ends and in three different lengths. It has four branches pointing downward and coming from the main stent graft at two levels. It offers the physician an opportunity to decide which branch to choose for the target vessel. It may be implanted alone or extended proximally and distally. Balloon expandable and/or self-expanding stent grafts are used to create the visceral branches. In complex extensive aneurysms, the procedure is divided into two or three stages to minimize the risks of spinal cord ischemia.

Results

Between August 2015 and December 2021, twenty-two Colt stent grafts were implanted in twenty males and two females (aged 56-81) with TAAAs (eight Type II; twelve Type III; two Type IV). The mean aneurysm diameter was 73.4 mm (range 64-83). All patients were asymptomatic. Eighty-five target vessels were reconstructed using either self-expanding or balloon-expandable stent grafts. Fourteen bifurcated, six custom-made tubes and two aortouniiliac (AUI) stent grafts were used as distal extensions to the Colt device. Completion angiography revealed no type I endoleaks. Five patients had Type II endoleaks which were treated conservatively. There were no intraoperative deaths. One patient died on the 7th postoperative day from multiorgan failure. We did not observe any other complications within 30 days after implantation. One patient died from Covid-19 two months after discharge. Follow-up ranged from three to 75 months. There was no migration or dislocation of the docking station or proximal and distal extensions. All Colt device prostheses remained patent, however, two branches leading to the coeliac trunk were found occluded at the time of the 12-month CTA, without any symptoms. In two patients, there were late problems with three renal bridging stent grafts. One of the Type II endoleaks resolved spontaneously after one year, while four others remain under observation. No patient had an increase in sac diameter.

Conclusions

Results from the current series are promising. The Colt stent graft can be applied to a large variety of TAAA anatomies, which may facilitate the development of new "off-the-shelf" devices in the future.

Early and mid-term outcomes of thoracic endovascular aortic repair to treat aortic rupture in patients with aneurysms, dissections and trauma

OBJECTIVES

The aim of this study was to analyse outcomes of thoracic endovascular aortic repair to treat aortic rupture.

METHODS

Patient and outcome characteristics of all emergent endovascular treatments for thoracic aortic rupture between January 2009 and December 2019 were analysed.

RESULTS

Thoracic aortic rupture occurred in patients with aortic aneurysms (n = 42, 49%), aortic dissection (n = 13, 16%) or after trauma (n = 30, 35%). Preoperative cerebrospinal fluid drainage was placed in 9 patients (11%) and 18 patients (21%) underwent perioperative supra-aortic transposition. The proximal landing zones were: zone 1 (n = 1, 1%), zone 2 (n = 23, 27%), zone 3 (n = 52, 61%) and zone 4 (n = 9, 11%). Temporary spinal cord injury occurred in 1 patient (1%), permanent spinal cord injury in 7 patients (8%). Two patients (2%) experienced a postoperative stroke. Seventeen patients (20%) expired in-hospital. Aortic dissection (odds ratio: 16.246, p = 0.001), aneurysm (odds ratio: 9.090, P = 0.003) and preoperative shock (odds ratio: 4.646, P < 0.001) were predictive for mortality. Eighteen patients (21%) required a stent-graft-related aortic reintervention for symptomatic supra-aortic malperfusion (n = 3, 4%), endoleaks (n = 6, 7%), a second aortic rupture (n = 4, 5%), retrograde type A aortic dissection (n = 2, 2%), aortic-oesophageal fistulation (n = 2, 2%) and stent-graft kinking (n = 1, 1%).

CONCLUSIONS

Thoracic endovascular aortic repair in patients with aortic rupture has become a valuable treatment modality to stabilize patients. However, a significant risk of postoperative morbidity and mortality remains, particularly in patients with aortic dissections, aneurysms or shock. Patients require thorough follow-up ideally in an aortic clinic with a staff having the entire spectrum of cardiovascular and thoracic surgical expertise.

Simultaneous Endovascular Repair Is Not Associated With Increased Risk for Thoracic and Abdominal Aortic Pathologies: Early and Midterm Outcomes

Coexisting multilevel aortic pathologies were caused by atherosclerosis and hypertension and presented in a small subgroup of patients. Endovascular repair is a safe and effective treatment for a variety of aortic pathologies. However, fewer small series and cases were reported using simultaneous thoracic endovascular repair (TEVAR) and endovascular aneurysm repair (EVAR) for both aortic segments. To determine the outcomes of simultaneous and separately TEVAR and EVAR treating for multilevel aortic pathologies. Between 2010 and 2020, 31 patients and 22 patients were treated by one-staged and two-staged repair, respectively at a single center. All patients had the concomitant thoracic and abdominal aortic disease (aortic dissection, aneurysms, and penetrating aortic ulcers). Compared with the patients with two-staged aortic repair, the one-staged repair patients were older (mean age, 68 vs. 57 years; P < 0.001) and had a larger preoperative maximal aortic diameter (67.03 ± 10.65 vs. 57.45 ± 10.36 mm; p = 0.002). The intraoperative and postoperative outcomes show that the procedure times and length of hospital stay (LOS) were longer in the two-staged group. There is no significant difference in postoperative complications between the two groups. In the follow up, the freedom from re–intervention and the mean survival rate for the one-staged group were 100 vs. 100%, 92.4 vs. 95%, and 88 vs. 88% at one, two, and 5 years, respectively, whereas the mean survival rate for the two-staged group was 86.4 vs. 90.5%, 87 vs. 90.5%, and 76 vs. 84% at one, two, and 5 years, respectively, all with no statistical difference. Combined TEVAR and EVAR can be performed successfully with minimal morbidity and mortality. The one-staged repair was not associated with the increased risk for multilevel aortic pathologies treatment.

Staging Endovascular Thoracic and Thoracoabdominal Aortic Aneurysm Repairs and the Risk of Post-operative Spinal Cord Ischemia

OBJECTIVE

Staged aortic aneurysm repair is one method used to decrease the risk of spinal cord ischemia (SCI) following endovascular aortic intervention. Sequential sacrifice of arteries perfusing the spine may allow for improved spinal perfusion through the development of collateral networks over time. To evaluate the impact of staging endovascular aortic aneurysm repairs on SCI, we conducted a conservative analysis of Vascular Quality Initiative (VQI) data.

METHODS

De-identified VQI data were queried for cases of endovascular thoracic and thoracoabdominal aneurysm repairs from year 2014 to 2019. Cases were selected based on inclusion criteria: aneurysmal disease, no ruptures, no prior aortic surgeries, no retreatments, and only cases with complete data on aortic zones and SCI. Chi-square, Student's t-tests, and Mann-Whitney U tests were used for univariable analyses, as appropriate. Logistic regression analyses were used to identify independent predictors of outcome.

RESULTS

There were 116 staged aortic repairs (SARs) (8.2%) performed out of a total of 1421 endovascular aortic repairs that fit study criteria. The overall rate of SCI within the study cohort was 3.4% (n = 48). The distribution of SARs and SCI events according to aortic zone coverage are displayed in Table 1. Patients who underwent staged endovascular aortic repairs had higher rates of SCI, pre-op spinal drain placement, non-African-American race, COPD, smoking history, positive stress tests, aspirin and statin use, increased estimated blood loss, physician-modified endografts, number of aortic zones covered, lower pre-op hemoglobin levels, larger aneurysm sac size, fusiform aneurysms, and longer total procedure times, Table 2. After adjusting for factors associated with SCI, a priori, and factors with a P < 0.1 univariable analysis, SAR was not associated with SCI (odds ratio [OR] = 1.86, 95% confidence interval [CI] = 0.77-4.50, P = 0.17). Of the six factors associated with SCI on univariable analysis, only procedure time ≥6 hours (OR = 2.49, 95% CI = 1.09-5.70, P = 0.031) and the number of aortic zones covered (OR = 1.15, 95% CI = 1.00-1.32, P = 0.047) were predictive of SCI. Staged repairs had a lower proportion of permanent SCI (38%, 3 of 8 cases) compared with repairs that were not staged (68%, 27 of 40 cases), with a relative risk reduction of 44% for those who developed SCI, P = 0.21.

CONCLUSIONS

In a large national data set, SARs were performed for patients with more extensive aortic disease. SARs were only performed in about 8% of cases and the rate of SCI remained low. After adjusting for baseline comorbidities, extent of aortic disease, and other factors that may potentiate SCI, staged aortic aneurysm repair had a similar risk of SCI compared with non-staged repairs. However, there was a trend toward decreased permanent SCI risk in the SAR group.

Astragalin Protects against Spinal Cord Ischemia Reperfusion Injury through Attenuating Oxidative Stress-Induced Necroptosis

Spinal cord ischemia/reperfusion (SCI/R) injury is a devastating complication usually occurring after thoracoabdominal aortic surgery. However, it remains unsatisfactory for its intervention by using pharmacological strategies. Oxidative stress is a main pharmacological process involved in SCI/R, which will elicit downstream programmed cell death such as the novel defined necroptosis. Astragalin is a bioactive natural flavonoid with a wide spectrum of pharmacological activities. Herein, we firstly evaluated the effect of astragalin to oxidative stress as well as the possible downstream necroptosis after SCI/R in mice. Our results demonstrated that astragalin improves the ethological score and histopathological deterioration of SCI/R mice. Astragalin mitigates oxidative stress and ameliorates inflammation after SCI/R. Astragalin blocks necroptosis induced by SCI/R. That is, the amelioration of astragalin to the motoneuron injury and histopathological changes. Indicators of oxidative stress, inflammation, and necroptosis after SCI/R were significantly blocked. Summarily, we firstly illustrated the protection of astragalin against SCI/R through its blockage to the necroptosis at downstream of oxidative stress.

Prior Infrarenal Aortic Surgery is Not Associated with Increased Risk of Spinal Cord Ischemia Following Thoracic Endovascular Aortic Repair and Complex Endovascular Aortic Repair

OBJECTIVES

Patients with prior infrarenal aortic intervention represent an increasing demographic of patients undergoing thoracic endovascular aortic repair (TEVAR) and/or complex EVAR. Studies have suggested that prior abdominal aortic surgery is a risk factor for spinal cord ischemia (SCI). However, these results are largely based on single-center experiences with limited multi-institutional and national data assessing clinical outcomes in these patients. The objective of this study was to evaluate the effect of prior infrarenal aortic surgery on SCI.

METHODS

The Society for Vascular Surgery Vascular Quality Initiative database was retrospectively reviewed to identify all patients ≥18 years old undergoing TEVAR/complex EVAR from January 2012 to June 2020. Patients with previous thoracic or suprarenal aortic repairs were excluded. Baseline and procedural characteristics and postoperative outcomes were compared by group: TEVAR/complex EVAR with or without previous infrarenal aortic repair. The primary outcome was postoperative SCI. Secondary outcomes included postoperative hospital length of stay (LOS), bowel ischemia, renal ischemia, and 30-day mortality. Multivariate regression was used to determine independent predictors of postoperative SCI. Additional analysis was performed for patients undergoing isolated TEVAR.

RESULTS

A total of 9506 patients met the inclusion criteria: 8691 (91.4%) had no history of infrarenal aortic repair and 815 (8.6%) had previous infrarenal aortic repair. Patients with previous infrarenal repair were older with an increased prevalence of chronic kidney disease (p=0.001) and cardiovascular risk factors including hypertension, chronic obstructive pulmonary disease, and smoking history (p<0.001). These patients presented with larger maximal aortic diameters (6.06±1.47 cm versus 5.15±1.76 cm; p<0.001) and required more stent grafts (p<0.001) with increased intraoperative blood transfusion requirements (p<0.001), and longer procedure times (p<0.001). Univariate analysis demonstrated no difference in postoperative SCI, postoperative hospital LOS, bowel ischemia, or renal ischemia between the two groups. Thirty-day mortality was significantly higher in patients with prior infrarenal repair (p=0.001). On multivariate regression, prior infrarenal aortic repair was not a predictor of postoperative SCI, while aortic dissection (odds ratio [OR] 1.65; 95% confidence interval [CI] 1.26-2.16, p<0.001), number of stent grafts deployed (OR 1.45; 95% CI 1.30-1.62, p<0.001), and units of packed red blood cells transfused intraoperatively (OR 1.33; 95% CI 1.03-1.73, p=0.032) were independent predictors of SCI.

CONCLUSIONS

Although TEVAR/complex EVAR patients with prior infrarenal aortic repair constituted a sicker cohort with higher 30-day mortality, the rate of SCI was comparable to patients without prior repair. Previous infrarenal repair was not associated with risk of SCI.

Feasibility and Preliminary Patency of Prophylactic Hypogastric Artery Stenting for Prevention of Spinal Cord Ischemia in Complex Endovascular Aortic Repair

BACKGROUND

To report early results of feasibility and patency of prophylactic hypogastric artery (HA) stenting during complex endovascular aortic repair.

METHODS

This is a single centre retrospective non comparative cohort study of all consecutive patients undergoing prophylactic HA stenting during fenestrated and/or branched EVAR (F/B EVAR) in order to prevent spinal cord ischemia (SCI). Endpoints included technical success and early outcomes in terms of morbidity, mortality and patency of the implanted stents.

RESULTS

Between May 2014 and June 2019 prophylactic HA stenting was performed in 36 consecutive patients with significant HA stenosis during F/B EVAR to prevent SCI. 69.4% of patients presented with asymptomatic, 25% with symptomatic and 5.6% with ruptured aortic aneurysms. 55.6% were treated for thoracoabdominal aortic aneurysms, 44.4% for pararenal abdominal aortic aneurysms. In 13.9% aortic coverage was limited to the abdominal aorta. In 86.1% the aortic coverage was in the thoracoabdominal aortic segment. Unilateral HA stenting was performed in 91.7%, whereas 8.3% underwent bilateral stenting. Technical success was 100%. The primary patency of the implanted stents after a median follow-up time of 9.5 months was 97.5%. One intraprocedural bleeding from an HA branch occurred and was successfully treated by coil embolization. No further procedure-related complications occurred. 11.1% of the patients developed SCI.

CONCLUSIONS

HA stenting is feasible and safe with high rates of technical success and short-term patency.

Management of Postoperative Complications Following Endovascular Aortic Aneurysm Repair

Endovascular aneurysm repair (EVAR) is a minimally invasive therapeutic approach to manage abdominal aortic pathologies (eg, aneurysm and dissection). EVAR was first introduced in 1991. In 1994, endovascular technique was also applied for thoracic aorta, thoracic endovascular aortic repair (TEVAR). In recent decades, EVAR has become an acceptable first-line treatment with 50% utilization rate across most practices, especially in high-risk patients. The safety profile of EVAR is comparable to the open approach, with superiority in terms of perioperative mortality and morbidity. This article summarizes the most common complications following EVAR/TEVAR and the most current treatment modalities across practices.

Inhibition of MALT1 Alleviates Spinal Ischemia/Reperfusion Injury-Induced Neuroinflammation by Modulating Glial Endoplasmic Reticulum Stress in Rats

PURPOSE

Glial activation and the disorders of cytokine secretion induced by endoplasmic reticulum stress (ERS) are crucial pathogenic processes in establishing ischemia/reperfusion (I/R) injury of the brain and spinal cord. This present study aimed to investigate the effects of mucous-associated lymphoid tissue lymphoma translocation protein 1 (MALT1) on spinal cord ischemia/reperfusion (SCI/R) injury via regulating glial ERS.

METHODS

SCI/R was induced by thoracic aorta occlusion-reperfusion in rats. The MALT1-specific inhibitor MI-2 or human recombinant MALT1 protein (hrMALT1) was administrated for three consecutive days after the surgery. Immunofluorescent staining was used to detect the localization of MALT1 and ERS profiles in activated astrocyte and microglia of spinal cord. The ultrastructure of endoplasmic reticulum (ER) was examined by transmission electron microscopy. Blood-spinal cord barrier (BSCB) disruption and noninflammatory status were assessed. The neuron loss and demyelination in the spinal cord were monitored, and the hindlimb motor function was evaluated in SCI/R rats.

RESULTS

Intraperitoneally postoperative MI-2 treatment down-regulated phos-NF-κB (p65) and Bip (ERS marker protein) expression in the spinal cord after SCI/R in rats. Intraperitoneal injection MI-2 attenuated the swelling/dilation of ER of the glia in SCI/R rats. Furthermore, MI-2 attenuated I/R-induced Evans blue (EB) leakage and microglia M1 polarization in spinal cord, implying a role for MALT1 in the BSCB destruction and neuroinflammation after SCI/R in rats. Furthermore, intrathecal injection of hrMALT1 aggravated the fragmentation of neuron, loss of neurofibrils and demyelination caused by I/R, while 4-PBA, an ERS inhibitor, co-treatment with hrMALT1 reversed these effects in SCI/R rats. hrMALT1 administration aggravated the motor deficit index (MDI) scoring, while 4-PBA co-treatment improved SCI/R-induced motor deficits in rats.

CONCLUSION

Inhibition of MALT1 alleviates SCI/R injury-induced neuroinflammation by modulating glial endoplasmic reticulum stress in rats.

Dynamics of Selected Biomarkers in Cerebrospinal Fluid During Complex Endovascular Aortic Repair - A Pilot Study

INTRODUCTION

Ischemic spinal cord injury (SCI) is a serious complication of complex aortic repair. Prophylactic cerebrospinal fluid (CSF) drainage, used to decrease lumbar cerebrospinal fluid (CSF) pressure, enables monitoring of CSF biomarkers that may aid in detecting impending SCI. We hypothesized that biomarkers, previously evaluated in traumatic SCI and brain injury, would be altered in CSF over time following complex endovascular aortic repair (cEVAR).

OBJECTIVES

To examine if a chosen cohort of CSF biomarker correlates to SCI and warrants further research.

METHODS

A prospective observational study on patients undergoing cEVAR with extensive aortic coverage. Vital parameters and CSF samples were collected on ten occasions during 72 hours post-surgery. A panel of ten biomarkers were analyzed (Neurofilament Light Polypeptide (NFL), Tau, Glial Fibrillary Acidic Protein (GFAP), Soluble Amyloid Precursos Protein (APP) α and β, Amyloid β 38, 40 and 42 (Aβ38, 40 and 42), Chitinase-3-like protein 1 (CHI3LI or YKL-40), Heart-type fatty acid binding protein (H-FABP).).

RESULTS

Nine patients (mean age 69, 7 males) were included. Median total aortic coverage was 68% [33, 98]. One patient died during the 30-day post-operative period. After an initial stable phase for the first few postoperative hours, most biomarkers showed an upward trend compared with baseline in all patients with >50% increase in value for NFL in 5/9 patients, in 7/9 patients for Tau and in 5/9 patients for GFAP. One patient developed spinal cord and supratentorial brain ischemia, confirmed with MRI. In this case, NF-L, GFAP and tau were markedly elevated compared with non-SCI patients (maximum increase compared with baseline in the SCI patient versus mean value of the maximal increase for all other patients: NF-L 367% vs 79%%, GFAP 95608% versus 3433%, tau 1020% vs 192%).

CONCLUSION

This study suggests an increase in all ten studied CSF biomarkers after coverage of spinal arteries during endovascular aortic repair. However, the pilot study was not able to establish a specific correlation between spinal fluid biomarker elevation and clinical symptoms of SCI due to small sample size and event rate.

Endovascular repair and open repair surgery of thoraco-abdominal aortic aneurysms cause drastically different types of spinal cord injury

Both endovascular repair (EVR) and open repair (OR) surgery of thoraco-abdominal aortic aneurysms cause spinal cord (SC) injury that can lead to paraparesis or paraplegia. It has been assumed that mechanisms responsible for SC damage after EVR are similar to those after OR. This pilot study compared the pathophysiology of SC injury after EVR versus OR using a newly developed EVR dog model. An increasing number of stents similar to those used in patients were inserted in the aorta of three dogs to ensure thoracic or thoracic plus lumbar coverage. The aorta of OR dogs was cross-clamped for 45 min. Behavior assessment demonstrated unique patterns of proprioceptive ataxia and evolving paraparesis in EVR versus irreversible paraplegia in OR. MRI showed posterior signal in lumbar SC after EVR versus central cord edema after OR. Histopathology showed white matter edema in L3-L5 localized to the dorsal column medial lemniscus area associated with loss of myelin basic protein but not neurons after EVR, versus massive neuronal loss in the gray matter in L3-L5 after OR. Metabolome analysis demonstrates a distinctive chemical fingerprint of cellular processes in both interventions. Our results call for the development of new therapeutics tailored to these distinct pathophysiologic findings.

Clinical trial outcomes and thoracic aortic morphometry after one year with the Valiant Navion stent graft system

AUTHORS' NOTE

On February 17, 2021, Medtronic Incorporated issued a global voluntary recall of the Valiant Navion Thoracic Stent Graft System (the device under study in the Valiant Evo Global Clinical Program that is the subject of this publication), and instructed physicians to immediately cease use of the Valiant Navion system and return any unused product. Medtronic initiated the recall in response to three clinical trial subjects recently observed with stent fractures, two of whom have confirmed type IIIb endoleaks. The data collection, analysis, and manuscript submission occurred before the notice of this recall, and, specifically, the 100 procedures reviewed for this series were free of events at 1 year related to the reason for this device recall. The authors of this article and the manufacturer were unaware of the recently detected adverse events at the time of the preparation of the manuscript, and the 1-year trial results, and imaging-based analyses described are unchanged. Management of thoracic aortic aneurysms continues to be a challenging problem and outcomes are dependent on patient anatomy. The present publication focuses on the importance of achieving proximal and distal seals and the consideration of the temporal changes of the aortic morphology as a part of the TEVAR planning process. The authors believe there is still scientific merit in disclosing this information, despite the current nonavailability of the Valiant Navion system.

OBJECTIVE

The Valiant Navion stent graft system (Medtronic Inc, Santa Rosa, Calif) is a third-generation device with improved conformability. We have reported the 1-year clinical trial outcomes, with a focus on an imaging-based analysis of the aortic morphology. We assessed the effects of graft implantation on the native anatomy and the effects of the 1-year changes in thoracic aorta morphology on the original seal zones of the stent graft.

METHODS

A total of 100 subjects were enrolled in a prospective single-arm clinical trial investigating the Valiant Navion stent graft system. An independent core laboratory (Syntactx, New York, NY) assessed the anatomic characteristics and performance outcomes.

RESULTS

Through 1 year of follow-up, the freedom from all-cause mortality, aneurysm-related mortality, and secondary procedures was 89.8%, 97.0%, and 94.8% respectively. Of the 100 patients, 5 had undergone a total of six secondary procedures, and 9 patients had developed an endoleak (type Ia and Ib in 1, type Ia in 1, type Ib in 3, and type II in 4 patients) within the first year. After 1 year, 2 of 76 patients (2.6%) had had an increase in their maximum aneurysm diameter of ≥5 mm, 62 (81.6%) had had stable sacs, and 12 (15.8%) had experienced sac shrinkage. Although no deployment failures had occurred, 36 of the 100 proximal (36%) and 31 of the 100 distal (31%) attachment zones were considered short according to our definitions. The stent graft had conformed to the native anatomy at implantation, because the preprocedural thoracic aorta tortuosity (1.45 ± 0.02) had not significantly changed at 1 month after implantation (1.46 ± 0.02). Despite a natural increase in thoracic tortuosity after 1 year (1.49 ± 0.02), wall apposition had been maintained over time, as evidenced by the low endoleak rates. Aortic elongation and dilation had occurred at the proximal end of the graft by an average of 1.2 mm and 1.6 mm, respectively. Aortic remodeling was more pronounced at the distal end, with an average increase of 4.2 mm in length and 2.8 mm in diameter.

CONCLUSIONS

The included patients had had positive 1-year outcomes with high freedom from mortality, endoleak development, and secondary procedures. Aortic elongation and dilation were more prevalent at the distal end, emphasizing the importance of distal attachment zone consideration as part of preoperative planning. Because aortic remodeling can be expected to continue over time, additional follow-up and imaging analysis in the trial will be necessary to assess the aortic morphology and its effects on stent graft performance.

Narrative review on endovascular techniques for left subclavian artery revascularization during thoracic endovascular aortic repair and risk factors for postoperative stroke

OBJECTIVES

The aim of this study was to present a narrative review on endovascular techniques (ET) for revascularization of the left subclavian artery (LSA) during zone 2 thoracic endovascular aortic repair (TEVAR) and on risk factors for postoperative stroke following TEVAR procedures.

METHODS

Non-systematic search of the literature from the PubMed, Ovid and Scopus databases to identify relevant English-language articles fully published in the period 1 January 2010-1 August 2020.

RESULTS

Current general agreement is that LSA revascularization should be always attempted in the elective setting. Under urgent circumstances, it can be delayed but might be considered during the same session on a case-by-case basis. Three ET are currently available: (i) chimney/snorkels (also known as parallel grafts), (ii) fenestrations or branches and (iii) proximal scallops. The main issue with ET is the potential for increased peri-operative stroke risk owing to increased manipulation within the aortic arch. Also, they are relatively novel and further assessment of their long-term durability is needed. Intra-operative embolism and loss of left vertebral artery perfusion are hypothesized as the main causes of stroke in patients undergoing TEVAR.

CONCLUSIONS

The overall risk of stroke seems higher without LSA revascularization during zone 2 TEVAR. As LSA revascularization might have a direct effect in preventing posterior stroke, it should be routinely performed in elective cases, while a case-by-case evaluation can be made under urgent circumstances. While ET can provide effective options for LSA revascularization during zone 2 TEVAR, they are novel and need further durability assessment. Stroke after TEVAR is a multifactorial pathological process and preventing TEVAR-related cerebral injury remains a significant unmet clinical need.

MiR-126-3p-Enriched Extracellular Vesicles from Hypoxia-Preconditioned VSC 4.1 Neurons Attenuate Ischaemia-Reperfusion-Induced Pain Hypersensitivity by Regulating the PIK3R2-Mediated Pathway

Recent evidence suggests that hypoxia preconditioning can alter the microRNA (miRNA) profile of extracellular vesicles (EVs) and has better neuroprotective effects when enriched miRs are delivered to recipients. However, the roles of exosomal miRNAs in regulating ischaemia-reperfusion (IR)-induced pain hypersensitivity are largely unknown. Thus, we isolated EVs from normoxia-conditioned neurons (Nor-VSC EVs) and Hypo-VSC EVs by ultracentrifugation. After the initial screening by a microarray analysis and quantitative RT-PCR (qRT-PCR), miR-126-3p, which was detected as the most altered miR in the Hypo-VSC EVs, was further confirmed by applying GW4869 to inhibit exosomal secretion. Moreover, transfection with a miR-126 mimic obviously increased miR-126-3p expression in Nor-VSC EVs, whereas a miR-126 inhibitor prevented the increase in miR-126-3p in Hypo-VSC EVs. A rat model of pain was established by performing 8-min occlusion of the aorta. Following IR, compared with the Nor-VSC EVs- or antagomir-126-injected rats, the Hypo-VSC EVs-injected rats displayed improved pain hypersensitivity demonstrated as higher PWT and PWL values. Mechanistically, PIK3R2 is a target of miR-126-3p and might be a modulator of the phosphoinositide 3-kinase (PI3K)/Akt pathway as the PIK3R2 and PI3K immunoreactivities in each group were changed in opposite directions. Compared with the controls, higher protein levels of PI3K and phosphorylated Akt but lower levels of phosphorylated nuclear factor-κ B (NF-κB), tumour necrosis factor (TNF)-α and interleukin (IL)-1β were detected in the spinal cords of the Hypo-VSC EVs-injected rats, and these effects were impaired by an injection of Hypo-VSC EVs combined with antagomir-126. Collectively, the miR-126-3p-enriched Hypo-VSC EVs attenuated IR-induced pain hypersensitivity by restoring miR-126-3p expression in the injured spinal cord and subsequently modulating PIK3R2-mediated PI3K/Akt and NF-κB signalling pathways.

Management of Descending Thoracic Aortic Diseases: Similarities and Differences Among Cardiovascular Guidelines

Cardiovascular societies have developed recommendations regarding the management of thoracic aortic diseases. While improvements in treatment have been observed during the past decade in regard to patient selection, thoracic endovascular aortic repair (TEVAR) and associated techniques, and high-volume centralization, the broad expansion of TEVAR has raised considerations about its indications, appropriateness, limitations, and application. The aim of this systematic review was to assess the similarities and differences among current cardiovascular societies' guidelines for the management of thoracic aortic diseases. The MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials were searched from January 2009 to May 2020. The initial search identified 990 articles. After exclusion of duplicate or inappropriate articles, the final analysis included 5 articles from cardiovascular societies published between 2010 and 2020. Selected controversial topics were analyzed, including diagnosis, imaging, spinal cord ischemia prevention, and management of the most important thoracic aortic pathologies. The analysis included data concerning the therapeutic approach in acute and chronic type B aortic dissection, penetrating aortic ulcer, intramural hematoma, thoracic aortic aneurysm, and traumatic aortic injury, as well a discussion of inflammatory aneurysms, aortitis, and genetic syndromes. The review presents consistent and controversial recommendations, as well as "gray zone" issues that need further investigation. There was significant overlap and agreement among the 5 societies regarding the management of thoracic aortic diseases. Especially in dissection and aneurysm management, TEVAR has established its role as the treatment of choice. However, robust evidence is still needed in many aspects of the management of thoracic aortic pathologies.

Adverse Outcomes after Advanced EVAR in Patients with Sarcopaenia

PURPOSE

To determine whether low total psoas muscle area (tPMA), as a surrogate for sarcopaenia, is a predictor of adverse outcomes in patients undergoing advanced EVAR.

MATERIALS AND METHODS

A retrospective review of medical records was performed for 257 patients who underwent advanced EVAR (fenestrated or branched technique) in a single tertiary centre from 1 January 2008 to 1 September 2019. The study cohort was divided into tertiles based on tPMA measurement performed independently by two observers from a peri-procedural CT scan at the level of mid-L3 vertebral body. The low tertile was considered sarcopaenic. Logistic regression analysis was used to assess the association of tPMA with 30-day mortality and post-procedural complications. Univariable analysis and adjusted multivariable Cox regression were used to assess the association of tPMA with all-cause mortality.

RESULTS

A total of 257 patients comprised 193 males and 64 females with the mean age of 75.4 years (± 6.8) were included. Adjusted multivariable Cox regression revealed an 8% reduction in all-cause mortality for every 1 cm² increase in tPMA, P < 0.05. TPMA was associated with 30-day mortality (OR 0.85, 95% CI 0.75-0.96, P < 0.05) and spinal cord ischaemia (SCI) (OR 0.89, 95% CI 0.82-0.97, P < 0.05). For remaining post-procedural complications, tPMA was not a useful predictive tool. TPMA correlated negatively with hospital stay length (r_s-0.26, P < 0.001). Patients with lower tPMA were more likely to be discharged to a rehabilitation center (OR 0.93, 95% CI 0.87-0.98 , P < 0.05).

CONCLUSION

Measurement of tPMA can be a useful predictive tool for adverse outcomes after advanced EVAR.

LEVEL OF EVIDENCE

Level 3, Retrospective cohort study.

Neurologic complications of heart surgery

Cardiac surgeries are commonly associated with neurologic complications. The type and complexity of the surgery, as well as patients' comorbidities, determine the risk for these complications. Awareness and swift recognition of these complications may have significant implications on management and prognosis. Recent trials resulted in an expansion of the time window to treat patients with acute ischemic stroke with intravenous thrombolysis and/or mechanical thrombectomy using advanced neuroimaging for screening. The expanded time window increases the reperfusion treatment options for patients that suffer a periprocedural ischemic stroke. Moreover, there is now limited data available to help guide management of intracerebral hemorrhage in patients undergoing treatment with anticoagulation for highly thrombogenic conditions, such as left ventricular assist devices and mechanical valves. In addition to cerebrovascular complications patients undergoing heart surgery are at increased risk for seizures, contrast toxicity, cognitive changes, psychological complications, and peripheral nerve injuries. We review the neurological complications associated with the most common cardiac surgeries and discuss clinical presentation, diagnosis and management strategies.

Implementation of a treatment algorithm to decrease incidence of paralysis post endovascular thoracoabdominal aorta repair

BACKGROUND

Spinal cord ischemia (SCI) is a rare but devastating complication following aortic repair. Despite improvements in operative management and critical care of aortic disease patients, SCI remains one of the most serious and common complications after these procedures. Early recognition and rescue interventions can augment the outcome and reduce the morbidity or avoid permanent dysfunction. This is a single institution experience of creating an evidence-based algorithm for the treatment of SCI in patients after thoracoabdominal endovascular aortic repair (TEVAR).

INTERVENTION/METHODS

We implemented an evidence-based treatment algorithm for the management of acute SCI after TEVAR. A total of 131 TEVAR cases were reviewed, 59 cases preimplementation, and 72 cases postimplementation of an SCI treatment algorithm.

RESULTS

Lower extremity motor and/or sensory deficits were identified in 5.1% of preimplementation and 4.2% of postimplementation cases. SCI treatment interventions included increasing the mean arterial pressure (MAP) (66% pre and 100% post), placing lumbar drain (33% pre and 33% post), performing carotid subclavian bypass (33% pre and 33% post), initiating naloxone drip (66% pre and 100% post), and administering glipizide (0% pre and 100% post, P < .05). Long-term paralysis occurred in 66% of preimplementation and 0% of postimplementation cases.

CONCLUSIONS

By creating and implementing an SCI treatment algorithm we reduced both, time to detection and time to effective treatment of SCI and significantly improved our patients' neurological outcomes.

Involvement of the miR-137-3p/CAPN-2 Interaction in Ischemia-Reperfusion-Induced Neuronal Apoptosis through Modulation of p35 Cleavage and Subsequent Caspase-8 Overactivation

Background

Neuron survival after ischemia-reperfusion (IR) injury is the primary determinant of motor function prognosis. MicroRNA- (miR-) based gene therapy has gained attention recently. Our previous work explored the mechanisms by which miR-137-3p modulates neuronal apoptosis in both in vivo and in vitro IR models.

Methods

IR-induced motor dysfunction and spinal calpain (CAPN) subtype expression and subcellular localization were detected within 12 h post IR. Dysregulated miRs, including miR-137-3p, were identified by miR microarray analysis and confirmed by PCR. A luciferase assay confirmed CAPN-2 as a corresponding target of miR-137-3p, and their modulation of motor function was evaluated by intrathecal injection with synthetic miRs. CAPN-2 activity was measured by the intracellular Ca²⁺ concentration and mean fluorescence intensity in vitro. Neuronal apoptosis was detected by flow cytometry and TUNEL assay. The activities of p35, p25, Cdk5, and caspase-8 were evaluated by ELISA and Western blot after transfection with specific inhibitors and miRs.

Results

The IR-induced motor dysfunction time course was closely associated with upregulated expression of the CAPN-2 protein, which was mainly localized in neurons. The miR-137-3p/CAPN-2 interaction was confirmed by luciferase assay. The miR-137-3p mimic significantly improved IR-induced motor dysfunction and decreased CAPN-2 expression, even in combination with recombinant rat calpain-2 (rr-CALP2) injection, whereas the miR-137-3p inhibitor reversed these effects. Similar changes in the intracellular Ca²⁺ concentration, CAPN-2 expression, and CAPN-2 activity were observed when cells were exposed to oxygen-glucose deprivation and reperfusion (OGD/R) and transfected with synthetic miRs in vitro. Moreover, double fluorescence revealed identical neuronal localization of CAPN-2, p35, p25, and caspase-8. The decrease in CAPN-2 expression and activity was accompanied by the opposite changes in p35 activity and protein expression in cells transfected with the miR-137-3p mimic, roscovitine (a Cdk5 inhibitor), or Z-IETD-FMK (a caspase-8 inhibitor). Correspondingly, the abovementioned treatments resulted in a higher neuron survival rate than that of untreated neurons, as indicated by decreases in the apoptotic cell percentage and p25, Cdk5, caspase-8, and caspase-3 protein expression.

Conclusions

The miR-137-3p/CAPN-2 interaction modulates neuronal apoptosis during IR injury, possibly by inhibiting CAPN-2, which leads to p35 cleavage and inhibition of subsequent p25/Cdk5 and caspase-8 overactivation.

Complications and Management of the Thoracic Endovascular Aortic Repair

Endovascular treatment in thoracic aortic diseases has increased in use exponentially since Dake and colleagues first described the use of a home-made transluminal endovascular graft on 13 patients with descending thoracic aortic aneurysm at Stanford University in the early 1990s. Thoracic endovascular aneurysm repair (TEVAR) was initially developed for therapy in patients deemed unfit for open surgery. Innovations in endograft engineering design and popularization of endovascular techniques have transformed TEVAR to the predominant treatment choice in elective thoracic aortic repair. The number of TEVARs performed in the United States increased by 600% from 1998 to 2007, while the total number of thoracic aortic repairs increased by 60%. As larger multicenter trials and meta-analysis studies in the 2000s demonstrate the significant decrease in perioperative morbidity and mortality of TEVAR over open repair, TEVAR became incorporated into standard guidelines. The 2010 American consensus guidelines recommend TEVAR to be “strongly considered” when feasible for patients with degenerative or traumatic aneurysms of the descending thoracic aorta exceeding 5.5 cm, saccular aneurysms, or postoperative pseudoaneurysms. Nowadays, TEVAR is the predominant treatment for degenerative and traumatic descending thoracic aortic aneurysm repair. Although TEVAR has been shown to have decreased early morbidity and mortality compared with open surgical repair, endovascular manipulation of a diseased aorta with endovascular devices continues to have significant risks. Despite continued advancement in endovascular technique and devices since the first prospective trial examined the complications associated with TEVAR, common complications, two decades later, still include stroke, spinal cord ischemia, device failure, unintentional great vessel coverage, access site complications, and renal injury. In this article, we review common TEVAR complications with some corresponding radiographic imaging and their management.

Extravascular risk factors in the prognostic evaluation for spinal cord injury during thoraco-abdominal aortic aneurysm exclusion: a case report

Background

The etiology of delayed-onset spinal cord injury (SCI) following endovascular repair of thoraco-abdominal aortic aneurysms (TAAA) is still unclear and may be related to multiple factors. Extravascular factors, such as lumbar spinal stenosis (LSS), may play a significant role in the selection of patient at risk of SCI. In this report we describe a case of paraplegia following thoracic endovascular aortic repair (TEVAR) in a patient suffering from severe and symptomatic LSS and undergoing staged endovascular repair of a TAAA.

Case presentation

A 70-year-old man was admitted to our department with an asymptomatic type III TAAA in previous open repair for abdominal aortic aneurysm. The patient complained of buttock and thigh claudication in the absence of defects in the pelvic perfusion; a spinal magnetic resonance angiography (MRA) showed a severe narrowing of the lumbar canal.. After 24 h from first-step procedure (TEVAR) paraplegia was detected. A cerebrospinal fluid (CSF) drainage was then placed with incomplete recovery.

Conclusions

Stenotic damage to the spinal cord is thought to be the result of direct compression of the neural elements and ischemic disruption of arterial and venous structures surrounding the spinal cord. This comorbidity may constitute an additional anatomic risk factor in those patients currently recognized as prognostically associated to the development of SCI.

Serial Systemic Injections of Endotoxin (LPS) Elicit Neuroprotective Spinal Cord Microglia through IL-1-Dependent Cross Talk with Endothelial Cells

Microglia are dynamic immunosurveillance cells in the CNS. Whether microglia are protective or pathologic is context dependent; the outcome varies as a function of time relative to the stimulus, activation state of neighboring cells in the microenvironment or within progression of a particular disease. Although brain microglia can be "primed" using bacterial lipopolysaccharide (LPS)/endotoxin, it is unknown whether LPS delivered systemically can also induce neuroprotective microglia in the spinal cord. Here, we show that serial systemic injections of LPS (1 mg/kg, i.p., daily) for 4 consecutive days (LPSx4) consistently elicit a reactive spinal cord microglia response marked by dramatic morphologic changes, increased production of IL-1, and enhanced proliferation without triggering leukocyte recruitment or overt neuropathology. Following LPSx4, reactive microglia frequently contact spinal cord endothelial cells. Targeted ablation or selective expression of IL-1 and IL-1 receptor (IL-1R) in either microglia or endothelia reveal that IL-1-dependent signaling between these cells mediates microglia activation. Using a mouse model of ischemic spinal cord injury in male and female mice, we show that preoperative LPSx4 provides complete protection from ischemia-induced neuron loss and hindlimb paralysis. Neuroprotection is partly reversed by either pharmacological elimination of microglia or selective removal of IL-1R in microglia or endothelia. These data indicate that spinal cord microglia are amenable to therapeutic reprogramming via systemic manipulation and that this potential can be harnessed to protect the spinal cord from injury.SIGNIFICANCE STATEMENT Data in this report indicate that a neuroprotective spinal cord microglia response can be triggered by daily systemic injections of LPS over a period of 4 d (LPSx4). The LPSx4 regimen induces morphologic transformation and enhances proliferation of spinal cord microglia without causing neuropathology. Using advanced transgenic mouse technology, we show that IL-1-dependent microglia-endothelia cross talk is necessary for eliciting this spinal cord microglia phenotype and also for conferring optimal protection to spinal motor neurons from ischemic spinal cord injury (ISCI). Collectively, these novel data show that it is possible to consistently elicit spinal cord microglia via systemic delivery of inflammogens to achieve a therapeutically effective neuroprotective response against ISCI.