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.

Single-Site Review of Spinal Cord Protection Protocols Including the Utilization of Spinal Drains versus Medical Management with Branched Endovascular Aortic Repair.

BACKGROUND: Spinal cord ischemia (SCI) continues to be a devastating complication after repair of thoracoabdominal aortic aneurysms. The objective of this review is to present our single-center outcomes after the implementation of a standardized neuroprotective protocol following branched endovascular aortic repair. METHODS: A standardized neuroprotective protocol including preoperative steroids, acetazolamide, intraoperative hemodynamic parameters, and postoperative treatment goals was initiated in November 2019. Physician-modified branched endovascular repairs were completed at a single center from 2012 to 2021 with outcomes reviewed both before (n = 107) and after (n = 67) the implementation of the neuroprotective protocol. The primary end point was the incidence of any SCI event at 30 days. Secondary end points included all-cause mortality, stroke, myocardial infarction, and renal failure at 30 days. Patients with Crawford extents I-III, renal failure, or necessitating emergent repair were deemed high risk for SCI events and underwent a subset analysis. Survivability after SCI was estimated using Kaplan-Meier tables. RESULTS: Of the 174 consecutive patients treated, the 67 patients treated following implementation of the neuroprotective protocol were more likely to have experienced a prior myocardial infarction (26.9% vs. 14%; P = 0.0466) and have a history of chronic obstructive pulmonary disease (64.3% vs. 45.8%; P = 0.02). This group was more likely to be treated for paravisceral aneurysms (53.7% vs. 24.3%; P = 0.0002). Postprotocol implementation, spinal drain use was lower (6% vs. 38.3%; P = <0.0001) with 100% of these drains placed in urgent or unstaged thoracoabdominal aortic aneurysm repairs as a part of the protocol. Rates of any SCI event among all patients before and after implementation of the protocol were 9.3% (n = 10 of 107) and 6% (n = 4 of 67; P = 0.57), respectively. In comparison, the protocol significantly reduced SCI rates to 0 (0% vs. 17.1%; P = 0.0407) in high-risk patients. Frequency of renal failure was reduced (3% vs. 14%; P = 0.018) after initiation of the protocol. Patients in the postprotocol group had significantly improved 1-year mortality rate (9% vs. 27.1%; P = 0.0035) and renal failure rates (2% vs. 15%; P = 0.018). Regression models indicated that patients in the postprotocol group had lower likelihood of mortality and renal failure than patients in preprotocol group (P < 0.05) and that spinal drain reduced mortality (P < 0.1). CONCLUSIONS: Implementation of a standardized neuroprotective protocol that focuses on medical management and fluid dynamics may significantly reduce risk of SCI after branched endovascular repairs, with the most significant improvement of SCI outcomes involving those at greatest risk for developing SCI. Also noteworthy, there was significant improvement to 1-year survivability after the implementation of this neuroprotective protocol.

Practice of neuromonitoring in open and endovascular thoracoabdominal aortic repair-an international expert-based modified Delphi consensus study.

OBJECTIVES: Spinal cord injury is detrimental for patients undergoing open or endovascular thoracoabdominal aortic aneurysm (TAAA) repair. The aim of this survey and of the modified Delphi consensus was to gather information on current practices and standards in neuroprotection in patients undergoing open and endovascular TAAA. METHODS: The Aortic Association conducted an international online survey on neuromonitoring in open and endovascular TAAA repair. In a first round an expert panel put together a survey on different aspects of neuromonitoring. Based on the answers from the first round of the survey, 18 Delphi consensus questions were formulated. RESULTS: A total of 56 physicians completed the survey. Of these, 45 perform open and endovascular TAAA repair, 3 do open TAAA repair and 8 do endovascular TAAA repair. At least 1 neuromonitoring or protection modality is utilized during open TAAA surgery. Cerebrospinal fluid (CSF) drainage was used in 97.9%, near infrared spectroscopy in 70.8% and motor evoked potentials or somatosensory evoked potentials in 60.4%. Three of 53 centres do not utilize any form of neuromonitoring or protection during endovascular TAAA repair: 92.5% use CSF drainage; 35.8%, cerebral or paravertebral near infrared spectroscopy; and 24.5% motor evoked potentials or somatosensory evoked potentials. The utilization of CSF drainage and neuromonitoring varies depending on the extent of the TAAA repair. CONCLUSIONS: The results of this survey and of the Delphi consensus show that there is broad consensus on the importance of protecting the spinal cord to avoid spinal cord injury in patients undergoing open TAAA repair. Those measures are less frequently utilized in patients undergoing endovascular TAAA repair but should be considered, especially in patients who require extensive coverage of the thoracoabdominal aorta.

Effect of Sarcopenia on Mortality and Spinal Cord Ischaemia After Complex Aortic Aneurysm Repair: Systematic Review and Meta-Analysis.

OBJECTIVE: Sarcopenia has been related to higher mortality rates after abdominal aortic aneurysm repair. This analysis aimed to assess sarcopenia related mortality and spinal cord ischaemia (SCI) at 30 days, and mortality during the available follow up, in patients with complex aortic aneurysms, managed with open or endovascular interventions. DATA SOURCES: A search of the English literature, via Ovid, using Medline, EMBASE, and CENTRAL up to 15 June 2022 was done. REVIEW METHODS: This meta-analysis was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines and preregistered in PROSPERO (CRD42022338079). Observational studies (2000 - 2022), with five or more patients, reporting on sarcopenia related mortality and SCI at 30 days, and midterm mortality after thoraco-abdominal aneurysm repair (open or endovascular), were eligible. The ROBINS-I tool (Risk Of Bias In Non-Randomised Studies of Interventions) was used for risk of bias, and GRADE (Grading of Recommendations, Assessment, Development and Evaluation) for the assessment of evidence quality. The primary outcome was 30 day and midterm mortality, and the secondary outcome was SCI at 30 days, in sarcopenic and non-sarcopenic patients. The outcomes were summarised as odds ratio (OR) with 95% confidence intervals (CIs). RESULTS: Four retrospective studies (1 092 patients; 40.0% sarcopenic) were included. Thirty day mortality was similar, with low certainty between groups (6% [95% CI 1 - 11] in sarcopenic vs. 5% [95% CI 1 - 9] non-sarcopenic patients [OR 0.30, 95% CI -0.21 - 0.81; p = .94, Ι2 = 0%). The estimated midterm mortality was statistically significantly higher (very low certainty) in sarcopenic patients (25% [95% CI 0.19 - 0.31] vs. 13% [95% CI -0.03 - 0.29] in non-sarcopenic patients (1.11 OR 0.95, 95% CI -0.21 - 2.44; p < .001, Ι2 = 88.32%). SCI was significantly higher (very low certainty) in sarcopenic patients (19%, 95% CI 4 - 34) vs. 7% (95% CI 5 - 20) in non-sarcopenic patients (OR 1.80, 95% CI -0.17 - 3.78; Ι2 = 82.4%), despite an equal distribution of aneurysm type between the groups. CONCLUSION: Early mortality does not appear to be affected by sarcopenia in patients treated for thoraco-abdominal aneurysms. However, sarcopenia may be associated with higher peri-operative SCI and midterm mortality rates.

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.

Aggressive use of prophylactic cerebrospinal fluid drainage to prevent spinal cord ischemia during thoracic endovascular aortic repair is not supportive.

OBJECTIVES: We investigated whether prophylactic preoperative cerebrospinal fluid drainage (CSFD) was effective in preventing spinal cord ischemia (SCI) during thoracic endovascular aortic repair of degenerative descending thoracic aortic aneurysms, excluding dissecting aneurysms. METHODS: We retrospectively reviewed the medical records of patients who underwent thoracic endovascular aortic repair involving proximal landing zones 3 and 4 between 2009 and 2020. RESULTS: Eighty-nine patients with preemptive CSFD [68 men; median (range) age, 76.0 (71.0-81.0) years] and 115 patients without CSFD [89 men; median (range) age, 77.0 (74.0-81.5) years] were included in this study. Among them, 59 from each group were matched based on propensity scores to regulate for differences in backgrounds. The incidence rate of SCI was similar: 8/89 (9.0%) in the CSFD group and 6/115 (5.2%) in the non-CSFD group (P = 0.403). Shaggy aorta (odds ratio, 5.13; P = 0.004) and iliac artery access (odds ratio, 5.04; P = 0.005) were identified as positive predictors of SCI. Other clinically important confounders included Adamkiewicz artery coverage (odds ratio, 2.53; P = 0.108) and extensive stent graft coverage (>8 vertebrae) (odds ratio, 1.41; P = 0.541) were not statistically significant. Propensity score matching yielded similar incidence of SCI: 4/59 (6.8%) in the CSFD group and 3/59 (5.1%) in the non-CSFD group (P = 0.697). CONCLUSIONS: Aggressive use of prophylactic CSFD was not supportive in patients without complex risks of SCI.

Spinal Cord Ischemia following Simultaneous EVAR and TEVAR for Concomitant Thoracic and Abdominal Aortic Aneurysms.

BACKGROUND: In patients with abdominal aortic aneurysms, 10-20% has concomitant thoracic aortic pathologies. These are typically managed with staged endovascular aneurysm repair (EVAR) and thoracic endovascular aortic repair (TEVAR) due to a perceived higher risk of spinal cord ischemia from a simultaneous intervention. We aimed to determine the outcomes of patients undergoing simultaneous EVAR and TEVAR for concomitant aneurysms. METHODS: A retrospective cohort study was performed using the Vascular Quality Initiative registry from December 2003 to January 2021. Patients undergoing same day EVAR and TEVAR were included and analyzed in accordance with the Society for Vascular Surgery reporting standards. Primary outcomes were technical success and spinal cord ischemia. RESULTS: Simultaneous EVAR and TEVAR were performed in 25 patients. Median age was 75.0 (interquartile range [IQR], 63.0-79.0) years and 20 (80.0%) patients were male. Two (4.0%) patients were symptomatic and 4 (16.0%) presented with rupture. Median maximum infrarenal and thoracic aortic diameter was 57.0 (IQR, 52.0-65.0). Infrarenal aortic neck length was 15.0 mm (IQR, 10.0-25.0), and diameter was 27.0 mm (IQR, 24.5-30.0). Median procedure time was 185.0 min (IQR, 117.8-251.3), fluoroscopy time 32.7 min (IQR, 21.8-63.1), and contrast volume 165 mL (IQR, 115.0-207.0). There were 3 (12.0%) Type Ia endoleaks and 3 (12.0%) Type II endoleaks in EVAR's, with 1 (4.0%) Type Ia and 1 (4.0%) Type II endoleak in TEVARs. In-hospital mortality occurred in 3 (12.0%) patients (1 elective, 2 ruptures). Spinal cord ischemia occurred in 1 (4.0%) patient. This patient had a symptomatic aneurysm. Thoracic coverage extended from Zone 4 to Zone 5 and an emergent spinal drain was placed postoperatively. Symptoms were present on discharge. There was 1 (4.0%) conversion to open repair which occurred in a ruptured aneurysm. Technical success was achieved in 19 (76.0%) patients, however when excluding ruptured aneurysms, was achieved in 17 (81.0%) patients. Follow-up data was available for 19 (76.0%) patients at a median of 426.0 (IQR, 329.0-592.5) days postoperatively. A total of 3 (12.0%) patients died during the late mortality period, at a mean of 509.0 (±503.7) days. Median change in abdominal and thoracic aortic sac diameter was -1.35 mm (IQR, -11.5 to 2.5) and 8.0 (IQR, -10.5 to 12.0), respectively. CONCLUSIONS: Simultaneous EVAR and TEVAR for concomitant abdominal and thoracic aortic aneurysms can be performed with low rates of spinal cord ischemia. Short- and mid-term outcomes are acceptable.

Spinal cord ischemia complicating treatment of abdominal aortic aneurysms: a legal overview.

BACKGROUND AND AIM: Spinal cord ischemia following open or endovascular aneurysm repair of the abdominal aorta is rare but highly disabling complication. The aim of this work is to report on its occurrence and its legal consequences. METHODS: We report a case of spinal cord ischemia complicating an endovascular aortic repair, its management and sequalae, comparing it with the existing literature and we examine its legal consequences resulting in a malpractice lawsuit and the final decision of the judge. RESULTS: Although the causal relation between SCI and the neurological deficits reported were assessed by the Court, no element of responsibility imputable to the Hospital or the Medical Staff were found, since the defendant had made every effort to prevent it in the preoperatory setting, and to treat it once it established in the post-operative phase. CONCLUSIONS: predictable but unpreventable complications of necessary interventions rule out medical malpractice, as long as the patient is fully informed about the risks and benefits of the treatment, and provided that in the perioperative setting all due measures are taken in order to prevent it and treat it.

Fenestrated and Branched Endografts for Post-Dissection Thoraco-Abdominal Aneurysms: Results of a National Multicentre Study and Literature Review.

OBJECTIVE: Fenestrated and branched endografting (F/B-EVAR) has been proposed as an endovascular solution for chronic post-dissection thoraco-abdominal aneurysms (PD-TAAAs). The aim of this study was to analyse the experience of four high volume centres nationwide and the current available literature. METHODS: Data on patients undergoing F/B-EVAR in four Italian academic centres between 2008 and 2019 were collected, and those from patients with PD-TAAAs were analysed retrospectively. Peri-operative morbidity and mortality were assessed as early outcomes. Survival, freedom from re-intervention (FFR), target visceral vessel (TVV) patency, and aortic remodelling were assessed as follow up outcomes. A MEDLINE search was performed for studies published from 2008 to 2020 reporting on F/B-EVAR in PD-TAAAs. RESULTS: Among 351 patients who underwent F/B-EVAR for TAAAs, 37 (11%) had PD-TAAAs (Crawford's extent I-III: 35% - 95%). Overall, 135 TVVs (from true lumen 120; false lumen seven; both true and false lumen eight) were accommodated by fenestrations (96% - 71%) and branches (39% - 29%). Technical success (TS) was achieved in 34 (92%) cases with three failures due to endoleaks (Ia: 1; Ic: 1; III: 1). There were no 30 day deaths. No cases of permanent spinal cord ischaemia (SCI) were recorded and six (16%) patients suffered from transient deficits. Renal function worsening (eGFR < 30% than baseline) and pulmonary complications were reported in two (5%) and four (11%) cases, respectively. From the Kaplan-Meier analysis, three year survival, FFR, and TVV patency were 81%, 66%, and 97%, respectively. Radiological imaging was available for 30 (81%) patients at 12 months with complete false lumen thrombosis in 26 (87%). Two hundred and fifty-six patients were reported in seven published papers with TS, 30 day mortality, and SCI ranging from 99% to 100%, 0 to 6%, and 0 to 16%, respectively. The mean follow up ranged from 12 to 26 months, with estimated two year survival between 81% and 90% and a re-intervention rate between 19% and 53%. CONCLUSION: F/B-EVAR is effective to treat PD-TAAAs. A high re-intervention rate is necessary to complete the aneurysm exclusion and promote aortic remodelling successfully.

Neuromonitoring during descending aorta procedures.

Thoraco-abdominal aneurysm (TAA) repair carries a significant risk of spinal cord infarction. The latter results from irreversible changes in the spinal cord arterial network, e.g., sacrifice of the segmental arteries. Intra-operative neurophysiology with somatosensory and especially motor evoked potential (SEP and MEP respectively) monitoring, has emerged as an effective tool to assess the efficiency of the collateral blood flow, detect reversible spinal cord ischemia and guide the peri-operative multidisciplinary management to prevent postoperative paraplegia. The main roles of such monitoring include diagnosis of spinal cord vs peripheral limb ischemia, titration of mean arterial pressure during aortic clamping, the guidance of selective re-implantation of critical segmental arteries, and management of hemodynamics in the immediate postoperative period. In addition, manipulation of the aortic arch and proximal descending aorta, adds the risk of cerebral infarction from both low flow state and/or thromboembolic events. As such, EEG monitoring may be a useful add-on for either assessment of the efficiency of cerebral cooling as a neuroprotective method and/or for detection and treatment of reversible cerebral ischemia. This chapter presents the multimodality approach to open TAA monitoring as a versatile tool for the prevention of devastating postoperative neurologic deficits.

Coverage of the Coeliac Artery During Thoracic Endovascular Aortic Repair: A Systematic Review and Meta-Analysis.

OBJECTIVE: To investigate the clinical impact of coeliac artery (CA) coverage during thoracic endovascular aortic repair (TEVAR). METHODS: This systematic review and meta-analysis was conducted according to the PRISMA guidelines. Electronic databases were searched from 1989 to 2020 for studies reporting visceral ischaemia, spinal cord ischaemia (SCI), 30 day/in hospital mortality, endoleaks, re-intervention, and caudal stent graft migration following CA coverage in patients undergoing TEVAR. Meta-analysis was conducted using random effects modelling. The quality of the evidence was graded using the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach. RESULTS: Fifteen observational studies with 236 patients (108 male, age range 61.3 - 79 years) were included. The pooled visceral ischaemia rate was 13% with significant heterogeneity between studies (95% confidence intervals [CI] 4 - 24; I2 = 72%, p < .001). The SCI rate was 5% (95% CI 2 - 9; I2 = 0%); the 30 day/in hospital mortality was 4% (95% CI 1 - 7; I2 = 0%); the overall endoleak rate was 21% (95% CI 13 - 29; I2 = 35%) with a 5% (95% CI 0 - 13; I2 = 38%) rate of type Ib and 2% (95% CI 0 - 8; I2 = 43%) rate of type II endoleak from retrograde CA flow. The re-intervention rate was 13% (95% CI 6 - 22; I2 = 54%); the caudal stent graft migration rate was 3% (95% CI 0 - 9, I2 = 0%). The certainty of the body of evidence was judged to be very low for all outcomes. CONCLUSION: CA coverage during TEVAR is associated with high rates of visceral ischaemia, spinal cord ischaemia, 30 day/in hospital mortality, endoleaks, and re-intervention. Although the literature is of poor quality and questions remain over effects estimates, there is evidence that CA coverage should be avoided if at all possible, during TEVAR. REGISTRATION: PROSPERO registration number 244084.

Outcome of Elective and Emergency Open Thoraco-Abdominal Aortic Aneurysm Repair in 255 Cases: a Retrospective Single Centre Study.

OBJECTIVE: This study reports on open TAAA repair comparing short and long term patient outcome according to the type of repair defined by the Crawford classification and elective vs. emergency repair. Endpoints were death, acute kidney injury (AKI), sepsis, spinal cord ischaemia (SCI), and re-intervention rate. METHODS: This was a retrospective study reporting the outcomes of 255 patients (between 2006 and 2019), designed according to the STROBE criteria. RESULTS: The TAAA distribution was type I 25%, type II 26%, type III 23%, type IV 18%, and type V 7%. Fifty-one (20%) patients had an emergency procedure. Of all the patients, 51% had a history of aortic surgery, 58% suffered from post-dissection TAAA, and 26% had connective tissue disease. The in hospital mortality rate among electively treated patients was 16% (n = 33) vs. 35% (n = 18) in the emergency subgroup; the total mortality rate was 20% (n = 51). The adjusted odds ratio for in hospital death following emergency repair compared with elective repair was 2.52 (95% confidence interval [CI] 1.15 - 5.48). Temporary renal replacement therapy because of AKI was required in 29% (n = 74) of all patients, sepsis from different cause was observed in 37% (n = 94), and SCI in 7% (n = 18, 10 patients suffering from paraplegia and eight from paraparesis). The mean follow up time was 3.0 years (median 1.5, range 0 - 12.8 years). Aortic related re-intervention was required in 2.8%. The total mortality rate during follow up was 22.5% (n = 46); 5.3% (n = 11) of all patients died because of aortic related events. CONCLUSION: Open TAAA repair is associated with an important morbidity and mortality rate, yet the incidence of spinal cord ischaemia may be favourably low if a neuromonitoring protocol is applied. The aortic related re-intervention and aortic related mortality rate during follow up are low.

Surgical Strategy for Chronic Type B Dissecting Aortic Aneurysm to Prevent Aorta-Related Events.

BACKGROUND: This study was aimed to evaluate the outcomes of performing open repair or thoracic endovascular aortic repair for chronic type B dissecting aortic aneurysm. METHODS: From July 2004 to February 2019, 52 patients underwent surgery as open repair (n = 32) or endovascular repair (n = 20) for chronic type B dissecting aortic aneurysm. Replacement of the aorta was limited to the aneurysmal portion with or without reconstructing the visceral arteries or the segmental arteries. Stent grafts were deployed in the true lumen above the celiac artery to cover the primary entry for even DeBakey IIIb dissection. RESULTS: Operative mortality and morbidity rates, including spinal cord ischemia incidence, did not differ between the groups. Operative mortality and morbidity rates, including spinal cord ischemia incidence, did not differ between the groups. In the endovascular repair group, 3 patients died due to rupture of residual false lumen in the early, and late postoperative follow-up. The 5-year rate of freedom from all-cause death, aorta-related death, and aorta-related event were 84% ± 6%, 94% ± 3% and 84% ± 6%. The endovascular repair was independently associated with all-cause death (hazard ratio [HR], 5.7; confidence interval [CI], 1.02-31.6; P = 0.04) and aorta-related event (HR, 30.9; CI 4.9-195.0; P < 0.001). In the open group, postoperative residual aortic diameter was an independent predictor of aorta-related events, and the threshold was 41 mm. CONCLUSIONS: Open repair remains a better option than simple endovascular repair alone in DeBakey IIIb dissection, but the distal un-resected aortic portion over 41 mm was associated with late aortic events.

Open thoracoabdominal aortic aneurysm repair in a patient with myasthenia gravis.

Myasthenia gravis (MG) is an autoimmune neuromuscular junction disorder and rarely coexists with aortic aneurysms requiring open repair. A 66-year-old patient with MG underwent extended thoraco-abdominal aortic aneurysm (TAAA) repair 16 years after onset of type-B acute aortic dissection. At 62 years, the patient was diagnosed with MG (MGFA class IIIa) from positive anti-acetylcholine receptor antibody without thymoma. Preoperatively, MG was well-controlled by prednisolone, cyclosporin and pyridostigmine. Extent II TAAA repair was performed under general anaesthesia maintained by total intravenous anaesthesia. Transcranial motor-evoked potential and somatosensory-evoked potential were applied to monitor intraoperative spinal cord ischaemia and muscle weakness. Amplitudes of motor-evoked potential and somatosensory-evoked potential attenuated intraoperatively but normalized after reperfusion from the reconstructed tube graft. Perioperative steroid coverage was given against surgical stress. The patient was weaned from mechanical ventilatory support on postoperative day 7. No signs of spinal cord ischaemia or muscle weakness were seen.

Urgent endovascular repair of thoracoabdominal aneurysms using an off-the-shelf multibranched endograft.

OBJECTIVES: Our goal was to report outcomes of the endovascular repair of urgent thoracoabdominal aortic aneurysms (TAAAs) using the Cook Zenith t-Branch off-the-shelf multibranched endograft. METHODS: Between 2010 and 2020, we collected patients with TAAAs who received an urgent endovascular repair using the Cook Zenith t-Branch (had a rupture, symptoms or diameter >80 mm). Thirty-day mortality, spinal cord ischaemia (SCI) and clinical success were assessed as early outcomes. Freedom from reintervention, target visceral vessel patency and survival were considered during follow-up. RESULTS: Sixty-five cases were managed using the Cook Zenith t-Branch for 27 (42%) TAAA ruptures, 8 (12%) symptomatic TAAAs and 30 (46%) asymptomatic TAAAs with a diameter >80 mm. Crawford's extent I-II-III and IV were noted in 54 (83%) and 11 (17%), respectively. Eleven (17%) patients had SCI with 3 (5%) cases of permanent paraplegia. Postoperative dialysis (P = 0.04) and ruptured TAAAs (P = 0.05) were associated with SCI. Sixteen (25%) patients had reinterventions within the first 30 days postoperatively. The 30-day mortality was 14% (9). Ruptured TAAAs (P = 0.05) and technical failures (P = 0.01) were correlated with in-hospital mortality. Clinical success was 78% (51 patients). The mean follow-up was 18 ± 14 months. Survival at 24 months was 47% with no late TAAA-related deaths. Patients with ruptured TAAAs had lower survival than those who did not have ruptured TAAAs (52% vs 60% at 1 year; P = 0.05). Target visceral vessel patency and freedom from reintervention at 24 months were 89% and 60%, respectively. CONCLUSIONS: An off-the-shelf multibranched endograft is safe and effective for treating urgent TAAAs. Postoperative SCI and 30-day mortality are satisfactory for this challenging clinical scenario. The early reintervention rate is not negligible. Midterm survival is low, especially in patients with a ruptured TAAA; therefore, accurate patient selection is mandatory.

Towards rapid intraoperative axial localization of spinal cord ischemia with epidural diffuse correlation monitoring.

Spinal cord ischemia leads to iatrogenic injury in multiple surgical fields, and the ability to immediately identify onset and anatomic origin of ischemia is critical to its management. Current clinical monitoring, however, does not directly measure spinal cord blood flow, resulting in poor sensitivity/specificity, delayed alerts, and delayed intervention. We have developed an epidural device employing diffuse correlation spectroscopy (DCS) to monitor spinal cord ischemia continuously at multiple positions. We investigate the ability of this device to localize spinal cord ischemia in a porcine model and validate DCS versus Laser Doppler Flowmetry (LDF). Specifically, we demonstrate continuous (>0.1Hz) spatially resolved (3 locations) monitoring of spinal cord blood flow in a purely ischemic model with an epidural DCS probe. Changes in blood flow measured by DCS and LDF were highly correlated (r = 0.83). Spinal cord blood flow measured by DCS caudal to aortic occlusion decreased 62%. This monitor demonstrated a sensitivity of 0.87 and specificity of 0.91 for detection of a 25% decrease in flow. This technology may enable early identification and critically important localization of spinal cord ischemia.

Chronic type B aortic dissection complicated by repetitive spinal cord ischaemia.

Chronic type B aortic dissection complicated by repetitive transient spinal cord ischaemia is rare. Reduced blood flow in the segmental arteries supplying the radicular arteries in the false lumen is the main cause of this pathology. Individual variations in spinal cord circulation are difficult to identify; therefore, the mechanisms of spinal cord ischaemia are poorly understood. We encountered a patient with chronic type B aortic dissection experiencing repetitive spinal cord ischaemia that finally led to spinal cord infarction. The patient recovered, except for mild monoparesis of the right leg. With the growth of the dissected aorta, we planned for surgical treatment to restore the blood supply in the spinal cord. The patient underwent thoraco-abdominal aortic repair using deep hypothermia, and favourable neurological results were achieved.

A Study of Critical Events That Lead to Spinal Cord Injury and the Importance of Rapid Reversal of Surgical Steps in Improving Neurological Outcomes: A Porcine Model.

STUDY DESIGN: Porcine model. OBJECTIVE: To quantify critical vascular and mechanical events that occur before and during an evolving spinal cord injury. SUMMARY OF BACKGROUND DATA: Spinal cord injuries are one of the most devastating complications in spine surgery. Intraoperative neuromonitoring changes can occur as a secondary event of spinal cord compression and decrease in spinal cord blood flow (SCBF). Laser Doppler flowmetry has been well validated for measuring blood flow. METHODS: Seventeen pigs were studied, 14 of which completed the experiment. Multilevel, midthoracic laminectomies were performed. Laser Doppler flowmetry electrodes were placed on the dura to measure SCBF. Spinal cord injury was induced by incremental balloon inflation in the epidural space. The animals were separated into two groups. After motor-evoked potential (MEP) loss, group A underwent medical interventions and then balloon decompression approximately 20 minutes later. Group B underwent immediate balloon decompression followed by medical interventions. After interventions, wake-up test was performed and computed tomography scan measured thoracic spinal canal volume. RESULTS: Median SCBF changes were seen 15.8 (5.4-25.1) minutes before MEP loss. However, the 20% threshold interval was often reached before. At the 20% threshold, median pressure was 7 psi, balloon volume was 0.5 cm, and 50% of the spinal canal was compromised. In group A, no pigs moved and all had pathology indicating ischemia. In group B, 9 of 10 were found to be moving their hind legs with 7 indicating ischemia. CONCLUSION: Compression spinal cord injury is the end of a cascade involving increasing intracanal pressure, decreasing canal volume, and hypoperfusion. Rapid relief of compression leads to MEP return. SCBF monitoring can detect ischemia preinjury, giving surgeons an opportunity for early intervention. LEVEL OF EVIDENCE: 4.

Elective Multistaged Endovascular Repair of Thoraco-abdominal Aneurysms with Fenestrated and Branched Endografts to Mitigate Spinal Cord Ischaemia.

OBJECTIVE: To evaluate the safety and effectiveness of a multistaged approach for elective thoraco-abdominal aneurysm (TAAAs) repair by means of endovascular fenestrated and/or branched (F/B-EVAR) grafts. METHODS: Between 2013 and 2018, 80 high risk surgical patients received elective F/B-EVAR for TAAAs with a protocolled multistaged approach (thoracic, visceral, and limb steps) and were enrolled in an ambispective single centre study called STEAR (STaged Endovascular Aortic Repair - NCT03342755). Data regarding all study participants, single step mortality and morbidity (systemic complications) rates were recorded and the overall results were considered for statistical analysis. RESULTS: Previous aortic interventions (61/80 cases, 76.3%) combined with the TAAA extents resulted in different staging strategies: 58 patients (73%) had a thoracic step and 33 (41%) a limb step. The median TAAA treatment time was 77 days (50-107). The overall mortality was six cases (8%) and 30 day clinical success rate 64 cases (80%). The overall rate of grade 2 or 3 (including death) systemic complications was 19 cases (24%) and 20 patients (25%) experienced grade 1 complications. Three patients with type II or III TAAAs (4%) had permanent and fatal spinal cord (SC) impairment. On multivariable analysis, SC ischaemia was associated with an aortic coverage ≥350 mm (OR: 9.15, p = .03, 95% CI: 1.3-66.4) and bovine arch (OR: 10.6, p = .01, 95% CI: 1.6-68.6). The overall short term (six month) clinical success was 72 cases (90%) and none experienced SC ischaemia after late endoleak resolution or treatment. At mid term (mean follow up: 13.3 ± 15.4 months), the overall freedom from conversions, re-interventions, late rupture, or type I and III endoleaks was 57 of 72 survivors (79%). CONCLUSION: A multistaged approach with a third limb step in case of TAAAs is safe and technically feasible, with an acceptable rate of permanent spinal cord ischaemia. Different staging methods and protocols have been proposed and standardisation is required, especially for type I-II-III aneurysms.

Late-Onset Paraplegia After Endovascular Repair of Type B Aortic Dissection Managed by Urgent Left Subclavian Artery Revascularization: A Case Report.

Spinal cord ischemia is one of the most unpredictable and feared complications after open surgical or endovascular thoracic aortic repair. Protection of collateral network branches that contribute blood supply to spinal cord is fundamental in the prevention of this catastrophic condition. We report the case of a patient who underwent emergent endovascular treatment for a type B aortic dissection complicated by rupture of the false lumen, with intentional coverage of the left subclavian artery without revascularization. The patient developed paraplegia on the 10th postoperative day, which did not significantly improve with immediate cerebrospinal fluid drainage but fully recovered after urgent left carotid-subclavian bypass.