Adjunctive hyperbaric oxygen therapy for spinal cord ischemia after complex aortic repair.

OBJECTIVE: Spinal cord ischemia (SCI) with paraplegia or paraparesis is a devastating complication of complex aortic repair (CAR). Treatment includes cerebrospinal fluid drainage, maintenance of hemoglobin concentration (>10 g/L), and elevating mean arterial blood pressure. Animal and human case series have reported improvements in SCI outcomes with hyperbaric oxygen therapy (HBOT). We reviewed our center's experience with HBOT as a rescue treatment for spinal cord ischemia post-CAR in addition to standard treatment. METHODS: A retrospective review of the University Health Network's Hyperbaric Medicine Unit treatment database identified HBOT sessions for patients with SCI post-CAR between January 2013 and June 2021. Mean estimates of overall motor function scores were determined for postoperative, pre-HBOT, post-HBOT (within 4 hours of the final HBOT session), and at the final assessment (last available in-hospital evaluation) using a linear mixed model. A subgroup analysis compared the mean estimates of overall motor function scores between improvement and non-improvement groups at given timepoints. Improvement of motor function was defined as either a ≥2 point increase in overall muscle function score in patients with paraparesis or an upward change in motor deficit categorization (para/monoplegia, paraparesis, and no deficit). Subgroup analysis was performed by stratifying by improvement or non-improvement of motor function from pre-HBOT to final evaluation. RESULTS: Thirty patients were treated for SCI. Pre-HBOT, the motor deficit categorization was 10 paraplegia, three monoplegia, 16 paraparesis, and one unable to assess. At the final assessment, 14 patients demonstrated variable degrees of motor function improvement; eight patients demonstrated full motor function recovery. Seven of the 10 patients with paraplegia remained paraplegic despite HBOT. The estimated mean of overall muscle function score for pre-HBOT was 16.6 ± 2.9 (95% confidence interval [CI], 10.9-22.3) and for final assessment was 23.4 ± 2.9 (95% CI, 17.7-29.1). The estimated mean difference between pre-HBOT and final assessment overall muscle function score was 6.7 ± 3.1 (95% CI, 0.6-16.1). The estimated mean difference of the overall muscle function score between pre-HBOT and final assessment for the improved group was 16.6 ± 3.5 (95% CI, 7.5-25.7) vs -4.9 ± 4.2 (95% CI, -16.0 to 6.2) for the non-improved group. CONCLUSIONS: HBOT, in addition to standard treatment, may potentially improve recovery in spinal cord function following SCI post-CAR. However, the potential benefits of HBOT are not equally distributed among subgroups.

Prospective randomized pilot trial comparing prophylactic and therapeutic cerebrospinal fluid drainage during complex endovascular thoracoabdominal aortic aneurysm repair.

BACKGROUND: Endovascular techniques have transformed the management of thoracoabdominal aortic aneurysms (TAAAs). However, spinal cord ischemia (SCI) remains a prevalent and devastating complication. Prophylactic drainage of cerebrospinal fluid (CSF) is among the proposed strategies for prevention of SCI. Although prophylactic CSF drainage is widely used and conceptually attractive, prophylactic CSF drains have not been demonstrated to definitively prevent the occurrence nor mitigate the severity of SCI in endovascular TAAA repair. Whether or not outcomes of prophylactic drains are superior to therapeutic drains remains unknown. This pilot study was performed to determine the feasibility of a randomized clinical trial designed to investigate the role of prophylactic vs therapeutic CSF drains in the prevention of SCI in patients undergoing endovascular TAAA repair using branched and fenestrated endovascular aortic repair (FBEVAR). METHODS: This was a prospective multicenter randomized pilot clinical trial conducted at The University of Alabama at Birmingham and The University of Massachusetts. Twenty patients were enrolled and randomized to either the prophylactic drainage or therapeutic drainage groups, prior to undergoing FBEVAR for extensive TAAAs and arch aortic aneurysms. This was a pilot feasibility study that was not powered to detect statistical differences in clinical outcomes. The primary outcome was feasibility of randomization and compliance with a shared lumbar drain protocol. Secondary outcomes included rate of drain complications and SCI. RESULTS: Twenty patients were enrolled and successfully randomized, without any crossovers, to either the control cohort (n = 10), without prophylactic drains, or the experimental cohort (n = 10), with prophylactic drains. There were no differences in age, comorbidities, or history of prior aortic surgery across the cohorts. All patients were treated with FBEVAR. Aneurysm classifications were as follows: Extent I (10%), Extent II (50%), Extent III (35%), and Extent IV (5%). The average length of aortic coverage was 207 ± 21.6 mm. The length of aortic coverage did not vary across cohorts, nor did procedural times or blood loss volume. Compliance with the SCI prevention protocol was 100% across both groups. Within the prophylactic drain cohort, one patient experienced an adverse event related to lumbar drain placement, manifested as an epidural hematoma requiring laminectomy, without neurologic deficit (n = 1/10; 10%). There was one SCI event (n = 1/20; 5%), which occurred in the prophylactic drain cohort on postoperative day 9 following an episode of hypotension related to a gastrointestinal bleed. CONCLUSIONS: The role of prophylactic CSF drains for the prevention of SCI following endovascular TAAA repair is a topic of ongoing research, with many current practices based on expert opinion and experience, rather than rigorous scientific data. This study demonstrates the feasibility of a multicenter randomized clinical trial to evaluate the role of prophylactic vs therapeutic CSF drains in the prevention of SCI in patients undergoing endovascular TAAA repair.

Descending thoracic aortic mural ulceration is associated with postoperative spinal cord ischemia after branched endovascular aortic aneurysm repair.

OBJECTIVE: Paraplegia is one of the most feared complications after thoracoabdominal aortic aneurysm repair. The purpose of this study is to determine whether aortic thrombus characteristics are associated with spinal cord ischemia (SCI) after branched endovascular aneurysm repair (BEVAR). METHODS: From April 2011 to April 2020, 62 patients underwent elective BEVAR for thoracoabdominal aortic aneurysm and pararenal aortic aneurysms using a low-profile device and had a complete preoperative computed tomography angiography of the aorta from the sinotubular junction to the aortic bifurcation. Aortic thrombus was evaluated for thrombus thickness ≥5 mm, thrombus >2/3 of aortic circumference, and the presence of an ulcer-like thrombus. One point was assigned at each 5 mm axial image if all 3 criteria were met, resulting in a total "shaggy score" for the entire aorta. Data on demographics, procedural details, and outcomes were collected prospectively. All patients underwent a standard spinal cord protection protocol, including routine cerebrospinal fluid drainage. In July 2016, an insulin infusion protocol (IIP) was initiated to maintain postoperative blood glucose levels <120 mg/dL for 48 hours. The primary clinical end point was postoperative SCI. RESULTS: 10 (16%) patients developed postoperative SCI: 6 with transient paraparesis, 2 with persistent paraparesis, and 2 with persistent paraplegia. Patients with SCI were older, had higher shaggy scores, and were less likely to have been on an IIP. There were no significant differences in demographics, aneurysm type, or operative parameters. In a logistic multivariate regression model for SCI, age (odds ratio [OR]: 1.2 [1.1-1.4], P = .02) and shaggy score (OR: 1.2 [1.1-1.4], P = .02) were independently associated with increased risk of SCI, whereas treatment with the IIP was associated with lower risk of SCI (OR: 0.04 [0.006-0.50], P = .05). Of the individual components of the shaggy score, higher descending thoracic aortic ulcer scores were the most strongly associated with postoperative SCI (P = .009). CONCLUSIONS: Preoperative characterization of aortic wall thrombus is an important adjunctive tool for individualized clinical decision-making and patient counseling about the risk of SCI after BEVAR.

Early and midterm outcomes of fenestrated and branched endovascular aortic repair in thoracoabdominal aneurysms types I through III.

BACKGROUND: Fenestrated and branched endovascular aortic repair (F/BEVAR) of thoracoabdominal aortic aneurysms (TAAAs) has shown high technical success and low early mortality rates. Aneurysm extent has been reported as a factor affecting outcomes. This study aimed to assess the early and midterm follow-up outcomes of patients managed by F/BEVAR for types I through III TAAAs. METHODS: A single-center retrospective analysis was conducted, including data from consecutive, elective and urgent (symptomatic and ruptured cases), patients treated for types I through III TAAAs, between October 1, 2011, and October 1, 2022, using F/BEVAR. Degenerative and postdissection TAAAs were included. Patients received prophylactic cerebrospinal fluid drainage (CSFD), except those under therapeutic anticoagulation, those who were hemodynamically unstable, or those with failed CSFD application. When an initial thoracic endovascular aortic repair was performed, as part of a staged procedure, no CSFD was used. Later stages and nonstaged procedures were performed under CSFD. Thirty-day mortality and major adverse events (MAEs) were analyzed. Kaplan-Meier estimates were used for follow-up outcomes. RESULTS: F/BEVAR for types I through III TAAAs was performed in 209 patients (56.9% males; mean age, 69.6 ± 3.2 years; mean aneurysm diameter, 65.2 ± 6.2 mm); 29.2% type I, 57.9% type II, and 12.9% type III. Urgent repair was performed in 26.7% of patients (56 cases; 23 ruptured and 33 symptomatic cases) and 153 were treated electively. Thirty-two patients (15.3%) were classified as American Society of Anesthesiologists (ASA) class IV. CSFD was used in 91% and staged thoracic endovascular aortic repair was performed in 51.2% of patients. Technical success was 93.8% (96.7% in elective vs 94.6% in urgent cases; P = .92). Thirty-day mortality was 11.0% (4.6% in elective vs 28.5% in urgent cases; P < .001) and MAEs were recorded in 17.2% of cases (7.8% in elective vs 42.8% in urgent cases; P < .001). Spinal cord ischemia rate was 20.5% (17.6% in elective vs 28.7% in urgent cases; P = .08), whereas 2.9% of patients presented paraplegia (1.3% in elective and 7.1% in urgent cases; P = .03). The mean follow-up was 16 ± 5 months. Survival was 75.0% (standard error, 4.0%) and freedom from reintervention was 73.3% (standard error, 4.4%) at 36 months. ASA IV and urgent repair were detected as independent factors related to early mortality and MAE, whereas ruptured aneurysm status was related to spinal cord ischemia evolution. CONCLUSIONS: Endovascular repair for types I through III TAAAs provides encouraging early outcomes in terms of mortality, MAE, and paraplegia, especially in an elective setting. Setting of repair and baseline ASA score should be taken into consideration during decision-making.

Early and mid-term results after endovascular repair of thoracoabdominal aortic aneurysms using the off-the-shelf multibranched t-Branch device: a national multi-center study.

Objective: The multibranched off-the-shelf Zenith® t-Branch (Cook Medical, Bloomington, IN) device is commonly chosen for endovascular repair of thoracoabdominal aortic aneurysms. The aim of this study was to report early and mid-term outcomes in all patients treated with the t-Branch in Norway; Design and Methods: A retrospective multicenter study with Norwegian centers performing complex endovascular aortic repair was undertaken. T-Branch patients from 2014 to 2020 were included. All postoperative computed tomography angiography images were reviewed, and demographic, anatomical, perioperative and follow-up data were analyzed; Results: Seventy patients were treated in a single-step (n = 55) or staged (n = 15) procedure. Symptomatic presentation was seen in 20 patients, six of which had a contained rupture. Technical success was 87% (n = 59), with failures caused by unsuccessful bridging of target vessels (n = 4), target vessel bleeding (n = 3), persisting type 1c endoleak (n = 1) and t-Branch malrotation (n = 1). 30-day mortality was 9% (n = 6) and was associated with high BMI (p = .038). The spinal cord ischemia rate was 21% (n = 15) and was associated with type II aneurysms (OR 5.4, 95% CI 1.1-26.7, p = .04), smoking (OR 6.0, 95% CI 1.3-27.6, p = .02) and intraoperative blood loss (OR 1.1, 95% CI 1.0-1.3, p = .01). Survival at one, two and three years was 84 ± 4%, 70 ± 6% and 67 ± 6%, respectively. Freedom from aortic-related reinterventions at one, two and three years was 80 ± 5%, 65 ± 7% and 50 ± 8%, respectively; Conclusion: The study showed low early mortality (9%) and satisfactory mid-term survival. Technical success was achieved in acceptable 87% of procedures. The rate of spinal cord ischemia was high, occurring in 21% of patients.

This paper provides a national experience of all TAAA patients treated with the multibranched t-Branch stent graft in Norway in a multi-center study. As we aimed at including all Norwegian patients operated with the device, the paper adds real-world data on t-Branch outcomes from four regional smaller-volume vascular centers.The paper provides technical and clinical mid-term results with several patients being followed up for >3 years.Technical success was achieved in 87% of procedures.The 30-day mortality rate was 9% and survival at one, two and three years was 85 ± 4%, 70 ± 6% and 67 ± 6%, respectively.Spinal cord ischemia was associated with Crawford type II aneurysms, smoking and intraoperative blood loss.

Perioperative Cerebrospinal Fluid Drain Placement Does Not Increase Venous Thromboembolism Risk After Thoracic and Fenestrated Endovascular Aortic Repair.

BACKGROUND: Venous thromboembolism (VTE) incidence after thoracic and fenestrated endovascular aortic repair (TEVAR/FEVAR) is high (up to 6-7%) relative to other vascular procedures; however, the etiology for this discrepancy remains unknown. Notably, patients undergoing TEVAR/FEVAR commonly receive cerebrospinal fluid drains (CSFDs) for neuroprotection, requiring interruption of perioperative anticoagulation and prolonged immobility. We hypothesized that CSFDs are a risk factor for VTE after TEVAR/FEVAR. METHODS: Consecutive TEVAR/FEVAR patients at a single center were reviewed (2011-2020). Cerebrospinal fluid drains (CSFDs) were placed based on surgeon preference preoperatively or for spinal cord ischemia (SCI) rescue therapy postoperatively. The primary end-point was VTE occurrence, defined as any new deep venous thrombosis (DVT) or pulmonary embolism (PE) confirmed on imaging within 30 days postoperatively. Routine postoperative VTE screening was not performed. Patients with and without VTE, and subjects with and without CSFDs were compared. Logistic regression was used to explore associations between VTE incidence and CSFD exposure. RESULTS: Eight hundred ninety-seven patients underwent TEVAR/FEVAR and 43% (n = 387) received a CSFD at some point during their care (preoperative: 94% [n = 365/387]; postoperative SCI rescue therapy: 6% [n = 22/387]). CSFD patients were more likely to have previous aortic surgery (44% vs. 37%; P = 0.028) and received more postoperative blood products (780 vs. 405 mL; P = 0.005). The overall VTE incidence was 2.2% (n = 20). 70% (14) patients with VTE had DVT, 50% (10) had PE, and 20% (4) had DVT and PE. Among TEVAR/FEVAR patients with VTE, 65% (n = 13) were symptomatic. Most VTEs (90%, n = 18) were identified inhospital and the median time to diagnosis was 12.5 (interquartile range 7.5-18) days postoperatively. Patients with VTE were more likely to have nonelective surgery (95% vs. 41%; P < 0.001), had higher American Society of Anesthesiologists classification (4.1 vs. 3.7; P < 0.001), required longer intensive care unit admission (24 vs. 12 days; P < 0.001), and received more blood products (1,386 vs. 559 mL; P < 0.001). Venous thromboembolism (VTE) incidence was 1.8% in CSFD patients compared to 3.5% in non-CSFD patients (odds ratio 0.70 [95% confidence interval 0.28-1.78, P = 0.300). However, patients receiving CSFDs postoperatively for SCI rescue therapy had significantly greater VTE incidence (9.1% vs. 1.1%; P = 0.044). CONCLUSIONS: CSFD placement was not associated with an increased risk of VTE in patients undergoing TEVAR/FEVAR. Venous thromboembolism (VTE) risk was greater in patients undergoing nonelective surgery and those with complicated perioperative courses. Venous thromboembolism (VTE) risk was greater in patients receiving therapeutic CSFDs compared to prophylactic CSFDs, highlighting the importance of careful patient selection for prophylactic CSFD placement.

Outcomes of Staged Repairs of Complex Endovascular Repairs of Thoracoabdominal Aortic Aneurysms.

BACKGROUND: Endovascular treatment allows for the staging of thoracoabdominal aortic aneurysm repairs (eTAAAs) in an effort to decrease the risk of spinal cord ischemia (SCI), but data are limited. METHODS: We studied all eTAAAs in the Vascular Quality Initiative from 2014 to 2021. Inverse probability weighting was used to compare perioperative and long-term outcomes of staged and single-stage repairs. Thoracoabdominal life-altering events (TALEs) are the composite endpoint consisting of death/stroke/permanent SCI/permanent dialysis. RESULTS: There were 3,258 total operations during the study period. In total, 841 cases (26%) were staged repairs, and 2,417 (74%) were completed in a single stage, but in the cohort of patients with extensive aneurysms, 44% were staged. Staging methods included thoracic endograft (78%), branch (23%), and iliac (5%). Staged repairs were more often employed by high-volume surgeons at high-volume centers; for larger, more extensive aneurysms, with higher rates of prior aortic surgery. After adjustment, staged repair and single-stage treatment were associated with similar odds of all perioperative outcomes and including mortality, TALE, acute kidney injury, stroke, dialysis, and SCI, as well as long-term survival. This was consistent in the subgroups of patients with extensive aneurysms undergoing elective procedures. Of note, first-stage thoracic endografts were associated with 2.6% mortality, 7.3% TALE, 1.5% dialysis, and 4.1% SCI, and 25% of patients did not undergo a second stage. First-stage procedures accounted for one-third of perioperative complications including half of the deaths in the staged cohort. CONCLUSIONS: Staged eTAAA repairs were associated with similar perioperative and long-term complications to single-stage treatments. However, first stage procedures are associated with significant morbidity and mortality, and one-quarter of patients never complete their repairs. These data demonstrate the necessity of evaluating the outcomes of all patients planned for staged procedures, not only those who make it to the final stage. More data are needed as to the optimal method of spinal cord protection for these challenging aneurysms.

Perioperative Blood Transfusion Is Associated with Worse 30-Day Mortality and Complications After Thoracic Endovascular Aortic Repair.

BACKGROUND: It is not uncommon for patients requiring vascular surgery, and in particular aortic surgery, to have increased requirements for blood transfusion. However, studies examining the effects of perioperative transfusion for thoracic endovascular aortic repair (TEVAR) are limited. Using large multicenter data, we aimed to study the impact of perioperative blood transfusion on 30-day mortality and complications after TEVAR. METHODS: A total of 9,263 patients who underwent TEVAR were included in this retrospective study from the multicenter Vascular Quality Initiative cohort spanning 2010-2022. We excluded patients who were post-traumatic, anemic (World Health Organization criteria: hemoglobin < 12 g/dl and < 13 g/dl for females and males respectively), who underwent open conversions or presented with ruptured aneurysms. Primary outcomes were 30-day mortality and stroke. Secondary outcomes were postop congestive heart failure (CHF), respiratory complications, spinal cord ischemia (SCI), myocardial infarction (MI) and any postop complications (composite variable). Poisson regression with robust variance was performed to determine the risk of post op outcomes comparing patients who received red blood cells (RBCs) to those who did not. RESULTS: Comparing patients without any transfusion (n = 8,223), perioperative transfusion of 1-3 units (n = 735) was associated with 3-fold increased risk of 30-day mortality (adjusted relative risk [aRR] 3.30, 95% confidence interval [CI] 2.39,4.57, P < 0.001), almost 2-fold increased risk of stroke (aRR 1.98, 95% CI 1.24,3.15, P = 0.004), 2.7-fold increased risk of SCI (aRR 2.66, 95% CI 1.87-3.77, P < 0.001), 3-fold increased risk of MI (aRR 3.40, 95% CI 2.30, 5.03, P < 0.001), 2-fold increased risk of CHF (aRR 2.04, 95% CI 1.09, 3.83, P = 0.03), 3.5-fold increased risk of respiratory complications (aRR 3.49, 95% CI 2.67, 4.56, P < 0.001), and 2-fold increased risk of any postop complication (aRR 2.36, 95% CI 2.04, 2.73, P < 0.001). These effects were even higher in patients transfused 4 or more units (n = 305) than seen in the effects seen in those transfused 1-3 units; comparing each group to patients who received none. CONCLUSIONS: In hemodynamically stable patients undergoing TEVAR for nonemergent/emergent and nontraumatic indications, transfusion of any amount perioperatively is associated with worse 30-day mortality, stroke, SCI, MI, CHF, and respiratory complications. A conservative transfusion approach and multidisciplinary care to identify complications and rescue TEVAR patients who receive any amount of RBCs perioperatively might help improve outcomes. Future studies to understand the mechanisms of outcomes for transfused patients are needed.

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.

Intra-arterial thrombolysis with tenecteplase for the treatment of cervical spinal cord ischemia: Technical case report.

BACKGROUND: In recent years, there have anecdotal reports of intra-arterial thrombolysis (IAT) for the treatment of spinal cord ischemia (SCI) with encouraging results. We describe a patient with acute cervical SCI who underwent IAT with Tenecteplase at our institution. CASE PRESENTATION: A 20-year-old man presented to the emergency department with a 12-hour history of progressive onset upper and lower extremity numbness, weakness, and urinary incontinence after sustaining a fall. MRI of cervical spine demonstrated T2 and STIR hyperintensity in the ventral aspect of the spinal cord spanning the C3, C4, and C5 levels suggestive of SCI. He demonstrated progression of neurologic deficits to C4 ASIA B spinal cord injury with complete loss of motor function, diminished sensation, and absent rectal tone. Emergent angiography was performed with prominent anterior spinal supply via the left ascending cervical artery. A total of 30 mg of Tenecteplase was administered intra-arterially in the bilateral vertebral arteries, bilateral ascending cervical arteries, and bilateral inferior thyroid arteries. Two-week post-intervention neurologic examination demonstrated improvement in injury level and severity. The patient was C6 ASIA C SCI, with 2/5 strength in the distal upper and lower extremities and improved sensation. CONCLUSION: IAT with Tenecteplase may be a feasible option for the treatment of acute spinal cord ischemia in carefully selected patients.

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.

Spinal drain-related complications after complex endovascular aortic repair using a prophylactic automated volume-directed drainage protocol.

OBJECTIVE: A common measure to lower the risk for spinal cord ischemia (SCI) during complex endovascular aortic repair (cEVAR) is prophylactic cerebrospinal fluid drainage (CSFD). This method has caused controversy because of drain-related complications. Spinal drains are usually pressure directed. The objective of this study was to evaluate the risk of CSFD-related complications and SCI within the context of an automated volume-directed drain protocol. METHODS: This is a retrospective, single-center study of all cEVARs with CSFD at a tertiary vascular center between January 2014 and December 2020. Demographics, complications, and spinal drain data were recorded. All drainages were volume based using an automatic drainage system (LiquoGuard7; Möller Medical GmbH). Spinal drain complications were categorized as disabling and nondisabling according to the modified Rankin scale. The primary end point was any CSFD-related complication. RESULTS: A total of 448 cEVAR patients were identified, of whom 147 (32.8%) had prophylactic CSFD. The mean age was 69 years (63% male). The most common pathology (61%) was thoracoabdominal aortic aneurysm, and the most common procedure was branched EVAR (55.1%). Eighteen (12.2%) patients developed a CSFD-related complication, whereof three (2%) were disabling. Nineteen (13%) patients developed SCI: 12 (8.4%) paraparetic, 5 (3.4%) paraplegic, and 2 (1.4%) paresthesias. Of these, 13 (68%) had full reversal of symptoms, whereas 6 patients (4%) had residual symptoms and were deemed disabling. Drain-related complications were more common in patients with SCI (31.6%) compared with those without (9.4%, P = .014). In the latter group, only two patients (1.6%) developed a disabling drain-related complication. CONCLUSIONS: Selective use of prophylactic, automated volume-directed CSFD in patients at high risk for SCI was associated with a high incidence of complications and should be used with caution. Among those developing SCI, reversal was achieved frequently with increased CSFD volume, but at the price of more bleeding complications.

Incidence and risk factors for interval aortic events during staged fenestrated-branched endovascular aortic repair.

OBJECTIVE: Staged endovascular repair of complex aortic aneurysms with first-stage thoracic endovascular aortic repair may decrease the risk of spinal cord ischemia (SCI) associated with fenestrated-branched endovascular aortic repair (FB-EVAR) of thoracoabdominal aortic aneurysms or optimize the proximal landing zone in the cases requiring total aortic arch repair. However, a limitation of multistaged procedures is the risk of interval aortic events (IAEs) including mortality from a ruptured aneurysm. We aim to identify the incidence of and risk factors associated with IAEs during staged FB-EVAR. METHODS: This was a single-center, retrospective review of patients who underwent planned staged FB-EVAR from 2013 to 2021. Clinical and procedural details were reviewed. End points were the incidence of and risk factors associated with IAEs (defined as rupture, symptoms, and unexplained death) and outcomes in patients with or without IAEs. RESULTS: Of 591 planned FB-EVAR patients, 142 underwent first-stage repairs. Twenty-two did not have a planned second stage because of frailty, preference, severe comorbidities, or complications after the first stage and were excluded. The remaining 120 patients (mean age: 73 ± 6 years, 51% female) were planned for second-stage completion FB-EVAR and comprised our cohort. The incidence of IAEs was 13% (16 of 120). This included confirmed rupture in 6 patients, possible rupture in 4, symptomatic presentation in 4, and early unexplained interval death with possible rupture in 2. The median time to IAEs was 17 days (range: 2-101 days), and the median time to uncomplicated completion repairs was 82 days (interquartile range: 30-147 days). Age, sex, and comorbidities were similar between the groups. There were no differences in familial aortic disease, genetically triggered aneurysms, aneurysm extent, or presence of chronic dissection. Patients with IAEs had significantly larger aneurysm diameters than those without IAEs (76.6 vs 66.5 mm, P ≤ .001). This difference persisted with indexing for body surface area (aortic size index: 3.9 vs 3.5 cm/m2, P = .04) and height (aortic height index: 4.5 vs 3.9 cm/m, P ≤ .001). IAE mortality was 69% (11 of 16) compared with no perioperative deaths for those with uncomplicated completion repairs. CONCLUSIONS: The incidence of IAEs was 13% in patients planned for staged FB-EVAR. This represented a notable morbidity, including rupture, which must be balanced with SCI and landing zone optimization when planning repair. Larger aneurysms, especially when adjusted for body surface area, are associated with IAEs. Minimizing time between stages vs single-stage repairs for larger (>7 cm) complex aortic aneurysms in patients with reasonable SCI risk should be considered when planning repair.

Predictors and outcomes of spinal cord injury following complex branched/fenestrated endovascular aortic repair in the US Aortic Research Consortium.

OBJECTIVE: Spinal cord ischemia (SCI) is a well-known complication of thoracoabdominal aortic aneurysm repair and is associated with profound morbidity and mortality. The purpose of this study was to describe predictors for the development of SCI, as well as outcomes for patients who develop SCI, after branched/fenestrated endovascular aortic repair in a large cohort of centers with adjudicated physician-sponsored investigational device exemption studies. METHODS: We used a pooled dataset from nine US Aortic Research Consortium centers involved in investigational device exemption trials for treatment of suprarenal and thoracoabdominal aortic aneurysms. SCI was defined as new transient weakness (paraparesis) or permanent paraplegia after repair without other potential neurological etiologies. Multivariable analysis was performed to identify predictors of SCI, and life-table analysis and Kaplan-Meier methodologies were used to evaluate survival differences. RESULTS: A total of 1681 patients underwent branched/fenestrated endovascular aortic repair from 2005 to 2020. The overall rate of SCI was 7.1% (3.0% transient and 4.1% permanent). Predictors of SCI on multivariable analysis were Crawford Extent I, II, and III distribution of aortic disease (odds ratio [OR], 4.79; 95% confidence interval [CI], 4.77-4.81; P < .001), age ≥70 years (OR, 1.64; 95% CI, 1.63-1.64; P = .029), packed red blood cell transfusion (OR, 2.00; 95% CI, 1.99-2.00; P = .001), and a history of peripheral vascular disease (OR, 1.65; 95% CI, 1.64-1.65; P = .034). The median survival was significantly worse for patients with any degree of SCI compared with those without SCI (any SCI, 40.4 vs no SCI, 60.3 months; log-rank P < .001), and also worse in those with a permanent deficit (24.1 months) vs those with a transient deficit (62.4 months) (log-rank P < .001). The 1-year survival for patients who developed no SCI was 90.8%, compared with 73.9% in patients who developed any SCI. When stratified by degree of deficit, survival was 84.8% at 1 year for those who developed paraparesis and 66.2% for those who developed permanent deficits. CONCLUSIONS: The overall rates of any SCI at 7.1% and permanent deficit at 4.1% observed in this study compare favorably with those reported in contemporary literature. Our findings confirm that increased length of aortic disease is associated with SCI and those with Crawford Extent I to III thoracoabdominal aortic aneurysms are at highest risk. The long-term impact on patient mortality underscores the importance of preventive measures and rapid implementation of rescue protocols if and when deficits develop.

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.

Outcomes following thoracic endovascular aortic repair for blunt thoracic aortic injury stratified by Society for Vascular Surgery grade.

OBJECTIVES: Although the Society for Vascular Surgery (SVS) aortic injury grading system is used to depict the severity of injury in patients with blunt thoracic aortic injury, prior literature on its association with outcomes after thoracic endovascular aortic repair (TEVAR) is limited. METHODS: We identified patients undergoing TEVAR for BTAI within the VQI between 2013 and 2022. We stratified patients based on their SVS aortic injury grade (grade 1, intimal tear; grade 2, intramural hematoma; grade 3, pseudoaneurysm; and grade 4, transection or extravasation). We assessed perioperative outcomes and 5-year mortality using multivariable logistic and Cox regression analyses. Secondarily, we assessed the proportional trends in patients undergoing TEVAR based on SVS aortic injury grade over time. RESULTS: Overall, 1311 patients were included (grade1, 8%; grade 2, 19%; grade 3, 57%; grade 4, 17%). Baseline characteristics were similar, except for a higher prevalence of renal dysfunction, severe chest injury (Abbreviated Injury Score >3), and lower Glasgow Coma Scale with increasing aortic injury grade (Ptrend < .05). Rates of perioperative mortality by aortic injury grade were as follows: grade 1, 6.6%; grade 2, 4.9%; grade 3, 7.2%; and grade 4, 14% (Ptrend = .003) and 5-year mortality rates were 11% for grade 1, 10% for grade 2, 11% for grade 3, and 19% for grade 4 (P = .004). Patients with grade 1 injury had a high rate of spinal cord ischemia (2.8% vs grade 2, 0.40% vs grade 3, 0.40% vs grade 4, 2.7%; P = .008). After risk adjustment, there was no association between aortic injury grade and perioperative mortality (grade 4 vs grade 1, odds ratio, 1.3; 95% confidence interval, 0.50-3.5; P = .65), or 5-year mortality (grade 4 vs grade 1, hazard ratio, 1.1; 95% confidence interval, 0.52-2.30; P = .82). Although there was a trend for decrease in the proportion of patients undergoing TEVAR with a grade 2 BTAI (22% to 14%; Ptrend = .084), the proportion for grade 1 injury remained unchanged over time (6.0% to 5.1%; Ptrend = .69). CONCLUSIONS: After TEVAR for BTAI, there was higher perioperative and 5-year mortality in patients with grade 4 BTAI. However, after risk adjustment, there was no association between SVS aortic injury grade and perioperative and 5-year mortality in patients undergoing TEVAR for BTAI. More than 5% of patients with BTAI who underwent TEVAR had a grade 1 injury, with a concerning rate of spinal cord ischemia potentially attributable to TEVAR, and this proportion did not decrease over time. Further efforts should focus on enabling careful selection of patients with BTAI who will experience more benefit than harm from operative repair and preventing the inadvertent use of TEVAR in low-grade injuries.

Stem Cell Therapies for Restorative Treatments of Central Nervous System Ischemia-Reperfusion Injury.

Ischemic damage to the central nervous system (CNS) is a catastrophic postoperative complication of aortic occlusion subsequent to cardiovascular surgery that can cause brain impairment and sometimes even paraplegia. Over recent years, numerous studies have investigated techniques for protecting and revascularizing the nervous system during intraoperative ischemia; however, owing to a lack of knowledge of the physiological distinctions between the brain and spinal cord, as well as the limited availability of testing techniques and treatments for ischemia-reperfusion injury, the cause of brain and spinal cord ischemia-reperfusion injury remains poorly understood, and no adequate response steps are currently available in the clinic. Given the limited ability of the CNS to repair itself, it is of great clinical value to make full use of the proliferative and differentiation potential of stem cells to repair nerves in degenerated and necrotic regions by stem cell transplantation or mobilization, thereby introducing a novel concept for the treatment of severe CNS ischemia-reperfusion injury. This review summarizes the most recent advances in stem cell therapy for ischemia-reperfusion injury in the brain and spinal cord, aiming to advance basic research and the clinical use of stem cell therapy as a promising treatment for this condition.

Mouse Model of Spinal Cord Hypoperfusion with Immediate Paralysis Caused by Endovascular Repair of Thoracic Aortic Aneurysm.

BACKGROUND: A clinically relevant mouse model of thoracic endovascular aortic repair-induced ischemic spinal cord injury has been lacking since the procedure was first employed in 1991. The hypothesis was that ligation of mouse intercostal arteries would simulate thoracic endovascular aortic repair-induced ischemic spinal cord injury and behavioral deficit. The aim was to create a mouse model of thoracic endovascular aortic repair-induced spinal cord hypoperfusion by ligating five pairs of mouse intercostal vessels. METHODS: Mice were divided into sham (n = 53) and ligation (n = 60) groups. The procedures called for double ligation of three pairs and single ligation of two pairs of thoracic intercostal arteries in adult C57BL/6 mice. A laser Doppler probe was used in vivo on the spinal cords and intercostal arteries to document the extent of arterial ligation and spinal cord hypoperfusion. The Basso Mouse Scale for Locomotion, histological studies, and electron microscopy demonstrated postligation locomotive and histopathological changes. RESULTS: Ligation induced a significant and instantaneous drop in blood flow in the intercostal arteries (% change; mean = -63.81; 95% CI, -72.28 to -55.34) and the thoracic spinal cord (% change; mean = -68.55; 95% CI, -80.23 to -56.87). Paralysis onset was immediate and of varying degree, with behavioral deficit stratified into three groups: 9.4% exhibited severe paralysis, 37.5% moderate paralysis, and 53.1% mild paralysis at day 1 (n = 32; P < 0.001). Mild and moderate paralysis was transient, gradually improving over time. Severe paralysis showed no improvement and exhibited a higher mortality rate (83%; n = 15 of 18) compared to moderately (33%; n = 6 of 18) and mildly (24%; n = 6 of 25) paralyzed mice (P < 0.001). The overall ligation group survival rate (84%; n = 46 of 55) was significantly lower than the sham group (100%; n = 48 of 48) with P = 0.003. CONCLUSIONS: The mouse model generates reproducible spinal cord hypoperfusion and accompanying histopathological ischemic spinal cord damage. The resulting anatomical changes and variable behavioral deficits mimic the variability in radiological and clinical findings in human patients.

Chimney Technique and Single-Branched Stent Graft for the Left Subclavian Artery Preservation During Zone 2 Thoracic Endovascular Aortic Repair for Type B Acute Aortic Syndromes.

PURPOSE: The purpose of this study was to evaluate the efficacy and safety of zone 2 thoracic endovascular aortic repair assisted by the chimney technique or single-branched stent graft for the preservation of the left subclavian artery, and summarize our single-center experience with the techniques. MATERIALS AND METHODS: From February 2017 to June 2020, 137 patients who underwent left subclavian artery revascularization during zone 2 thoracic endovascular aortic repair were enrolled. Patients had acute type B aortic dissection and penetrating aortic ulcer associated with intramural hematoma. The chimney technique was performed in 68 patients (group A), and single-branched stent graft was deployed in 69 patients (group B). All procedures were performed during the acute phase. Primary technical success, immediate postoperative endoleak, neurologic complications (stroke or spinal cord ischemia), 30-day mortality, 1-year technical success, all-cause mortality, patency of the left subclavian artery, and reintervention were analyzed. Comparing the occurrence of the Bird-Beak Configuration, defined as a gap between the aortic wall and the sent graft with stent protrusion into the aortic lumen more than 5 mm, was also performed. RESULTS: Primary technique success was achieved in 66 and 67 patients in groups A and B, respectively. The incidence of immediate postoperative endoleak, neurologic complications (stroke or spinal cord ischemia), and 30-day mortality were 5.9%, 1.5%, and 4.4% in group A, and 2.9%, 2.9%, and 2.9% in group B, respectively. During follow-up, the 1-year technical success rate was similar in both groups. All-cause mortality was similar in both groups (3.1% in group A and 4.5% in group B). The patency of the left subclavian artery was not significantly different between the 2 groups with 2 and 3 occlusions in groups A and B, respectively. The rate of reintervention was higher in group B (3.1% vs 1.6%, p=0.536), with a non-significant difference. Bird-Beak Configuration was more prominent in group B with the incidence of 59.42%. CONCLUSIONS: Acting as minimally invasive alternatives, both techniques are feasible for left subclavian artery preservation during zone 2 thoracic endovascular aortic repair for type B acute aortic syndromes with encouraging mid-term outcomes. Long-term follow-up is required to confirm these findings.

Temporary Reperfusion of the Aneurysm Sac as a Prevention of Spinal Cord Ischemia After Endovascular Treatment of Thoracoabdominal Aortic Aneurysm: Systematic Review and Meta-analysis.

BACKGROUND: Spinal cord ischemia (SCI) is still a feared complication for patients suffering from thoracoabdominal aortic aneurysm (TAAA) who undergo endovascular treatment. The aims of this work are to review the available literature on different reperfusion methods of the aneurysm sac, and to analyze whether the different reperfusion methods, also in combination with other factors, are effective in reducing SCI risk and if the impact varies with the patient's age. METHODS: PubMed/MEDLINE library was searched for studies published until November 2020 concerning TAAA, endovascular repair, and SCI preventive measures. Systematic review and meta-analysis were conducted according to Preferred Reporting Items for Systematic reviews and Meta-Analyses criteria. Primary outcome consisted of correlation between endovascular repair techniques (type A: single step; type B: staged approach with reperfusion branches; type C: staged sequential approach with positioning of the thoracic component). A logistic-weighted regression for each event (SCI, transient, and permanent) was then performed with type of treatment, age, and interaction between them as input factors. Finally, another logistic-weighted regression was performed to analyze the other relevant factors for which observations are available together with the endovascular technique. RESULTS: Data from 53 studies with a total of 3095 patients were analyzed. Type A, type B, and type C endovascular strategies were adopted in 75%, 13%, and 12% of studied patients, respectively. Data showed that both type B and type C treatments are associated with lower risk of SCI, with a higher reduction of type C with respect to type B, although this positive trend is limited for elder patients. Moreover, a greater aortic diameter, a reduced aneurysm extent, and the absence of cerebrospinal fluid drainage positioning contribute to lower the risk of SCI. Concerning permanent SCI, both type B and type C are effective in reducing percentages for all ages, with type C treatment more beneficial for younger patients and type B for elder ones. CONCLUSION: According to the anatomy and the endovascular repair feasibility criteria, staged endovascular treatment appears to offer relevant advantages over single-step treatment in reducing the risk of SCI, regardless of the reperfusion method adopted.