The “bare branch” for safe spinal cord ischemia prevention after total endovascular repair of thoracoabdominal aneurysms

Efficacy and Safety of Endovascular Fenestrated and Branched Grafts Versus Open Surgery in Thoracoabdominal Aortic Aneurysm Repair: An Updated Systematic Review, Meta-analysis, and Meta-regression

OBJECTIVE

To provide an updated systematic review and meta-analysis with meta-regression of efficacy and safety of fenestrated/branched endovascular repair of thoracoabdominal aortic aneurysms (TAAAs) compared with open repair.

BACKGROUND

Endovascular repair of TAAAs may be a promising alternative to open surgery by reducing invasiveness and expanding the eligible population, but evidence remains limited.

METHODS

We applied "Prepared Items for Systematic Reviews and Meta-analysis" guidelines to retrieve, quantitatively pool, and critically evaluate the efficacy and safety (including 30-day mortality, reintervention, spinal cord injury [SCI], and renal injury) of both approaches. Original studies were retrieved from PubMed, Embase, and Cochrane Library until April 20, 2022, excluding papers reporting <10 patients. Pooled proportions and means were determined using a random-effect model. Heterogeneity between studies was evaluated with I2 statistics.

RESULTS

Sixty-four studies met the predefined inclusion criteria. Endovascular cohort patients were older and had higher rates of comorbidities. Endovascular repair was associated with similar proportions of mortality (0.07, 95% confidence intervals [CI]: 0.06-0.08) compared with open repair (0.09, 95% CI: 0.08-0.12; P = 0.22), higher proportions of reintervention (0.19, 95% CI: 0.13-0.26 vs 0.06, 95% CI: 0.04-0.10; P < 0.01), similar proportions of transient SCI (0.07, 95% CI: 0.05-0.09 vs 0.06, 95% CI: 0.05-0.08; P = 0.28), lower proportions of permanent SCI (0.04, 95% CI: 0.03-0.05 vs 0.06, 95% CI: 0.05-0.07; P < 0.01), and renal injury (0.08, 95% CI: 0.06-0.10 vs 0.13, 95% CI: 0.09-0.17; P = 0.02). Results were affected by high heterogeneity and potential publication bias.

CONCLUSIONS

Despite these limitations and the lack of randomized trials, this meta-analysis suggests that endovascular TAAA repair could be a safer alternative to the open approach.

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.

The "safe-line" technique as theoretical additional attempt to mitigate spinal cord ischemia after urgent complete endovascular exclusion of a thoracoabdominal aortic aneurysm

We describe the feasibility of a technique for temporary aneurysm sac reperfusion after endovascular single-stage thoracoabdominal aortic aneurysm exclusion, to be used in the case of postoperative spinal cord ischemia. Two cases were treated for impending rupture of a thoracoabdominal aortic aneurysm. Before completion of sac exclusion, a supplementary buddy wire (V-18 control guidewire; Boston Scientific) was advanced in parallel fashion from the left percutaneous femoral access into the aneurysmal sac on the posterior aspect of the endograft. Distal aneurysm exclusion was completed using the main superstiff guidewire, and the femoral access was closed with a percutaneous closure device (ProGlide; Abbott) in standard fashion, leaving in place the sole V-18 guidewire, draped in sterile fashion. In the case of spinal cord ischemia, the "safe-line" can be rapidly used for spinal reperfusion after trans-sealing exchange with a 6F, 65-cm-long Destination sheath (Terumo) connected to a 6F introducer on the contralateral femoral artery.

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.

Multi-staged endovascular repair of thoracoabdominal aneurysms by fenestrated and branched endografts

AIM

To report outcomes of a multi-staged approach for endovascular repair of thoracoabdominal aortic aneurysms (TAAAs) by fenestrated/branched endografting (F/B-EVAR).

METHODS

Between 2010 and 2020 (June), patients undergoing F/B-EVAR for TAAAs were collected. Data of cases managed by a multi-staged approach, to reduce the incidence of spinal cord ischemia (SCI), were retrospectively analyzed and reported in a cohort study. Thirty-day mortality and SCI were assessed as study's outcomes.

RESULTS

One hundred and thirty-seven patients underwent TAAAs repair by F/B-EVAR. A multi-staged approach was applied in 73(53%) cases, more frequently for Crawford's extent I-III (60/78) compared with IV (13/59) (P: <.0001). A complete TAAAs exclusion was achieved in 2, 3 or 4 steps in 64(88%), 8(11%) and 1(1%) cases, respectively, within the same hospitalization in 68(93%) cases. The mean time between first and last step was 16±8days, with a mean hospital stay of 21±12days. In 3(4%) cases the complete TAAA repair was not achieved due to inter-steps mortality (2) or permanent paraplegia (1). There were no cases of aortic rupture or target visceral vessels occlusions between the different steps. Seven (10%) patients suffered postoperative SCI with 2(4%) cases of permanent paraplegia. In 5/7 cases SCI occurred after the first stage; in 3/5 cases TAAAs exclusion was successfully completed with total SCI recovery. The 30-day mortality was 4% (3/73).

CONCLUSION

A multi-staged endovascular repair with F/B-EVAR can be safely performed for TAAAs repair. The majority of cases can be treated within a single, long hospitalization. The cost/effectiveness of the prolonged in-hospital time should be evaluated.

A systematic review and meta-analysis of the occurrence of spinal cord ischemia following endovascular repair of thoraco-abdominal aortic aneurysms

OBJECTIVE

The rates of endovascular repair of thoracoabdominal aortic aneurysms (TAAA-ER) have increased considerably in the last years. While mortality and morbidity rates have improved, spinal cord ischemia (SCI) rates have not declined significantly. The aim of this systematic review and meta-analysis was to examine SCI rates with respect to the efficacy of the different approaches.

METHODS

Cohort studies and case series (>20 patients) reporting SCI rates after TAAA-ER were eligible for inclusion. The primary outcome was the evaluation of SCI. Moderators considered were primarily the staged/non-staged approach, the use of cerebrospinal fluid drainage (CSFD) and TAAA extension. Permanent SCI and mortality rates were extracted.

RESULTS

Twenty-seven studies (n=2333 patients) were included in the meta-analysis. The pooled estimate for SCI was 11% (95% confidence interval [CI]: 8%-15%; I²:80%). For extent I,II,III and V TAAA, the pooled SCI rate was 13% (95% CI: 10%-17%; I²=71%), while for extent IV TAAA it was 6% (95% CI: 3%-10%; I²=62%). A staged TAAA-ER approach was used in 18 studies and a non-staged approach in 6 (one study included both). A lower pooled SCI rate was identified following staged compared with non-staged TAAA-ER (9% vs. 18%, respectively; P=.02). Staging was accomplished in >1 month in 9 studies and ≤1 month in 2, leading to similar SCI rates (7% vs. 11%, respectively; P=.29). The method of staging (thoracic-endoprosthesis or temporary aortic sac perfusion) did not affect SCI rates. Symptomatic CSFD was associated with a similar pooled rate of SCI compared with prophylactic CSFD (10% vs. 10%, respectively; P=.95). Pooled permanent SCI was 5% (6% following extent I,II,III and V TAAA; 3% following extent IV TAAA). Prophylactic or symptomatic CSFD have a similar rate of SCI (10% vs. 10%, respectively; P=.89). The pooled rate of 30-day mortality was 7%, with a similar incidence for the staged and non-staged approaches (6% vs. 9%, respectively). The inter-stage mortality was reported in 10 studies, with a pooled estimate rate of 1.6%.

CONCLUSIONS

SCI occurs in 11% of TAAA-ER and half of these cases are permanent. A staged approach can reduce SCI rates independently from the timing and the method adopted. The overall mortality rate for staged TAAA-ER is 6%, with one fourth of deaths (1.6%) occurring between stages.

Selective Versus Routine Spinal Drain Use for Fenestrated/Branched Endovascular Aortic Repair (F-BEVAR)

BACKGROUND

Spinal drains are used to ameliorate spinal cord ischemia (SCI), but their use may result in inherent morbidity and mortality. Although prophylactic spinal drain has proven of benefit in open repairs, that is not the case for endovascular repairs. The aim of this study was to assess the outcomes of spinal cord protection with and without the routine use of spinal drains during fenestrated-branched endovascular repair (F-BEVAR).

METHODS

A retrospective single center study was performed using a prospectively maintained dataset of all patients undergoing F-BEVAR over a 4-year period. The primary endpoint of the study was the frequency of SCI. Prophylactic spinal drain was placed pre-operatively in 33 patients (23%) with a median time for removal of 3 days (IQR, 2-3 days). Routine intraoperative neuromonitoring was used. Spinal cord protection relied primarily on maintaining a perioperative systolic blood pressure between 140 and 160 mm Hg or a mean arterial pressure >90 mm Hg, avoiding hypotension, preservation of as many collateral beds as possible, staged repairs and early lower extremity reperfusion based on neuromonitoring.

RESULTS

A total of 145 patients, 104 men (71%) and 41 women (28%) with a median age of 70 years (interquartile range [IQR], 53-62) underwent F-BEVAR. Branched custom-made devices (CMDs) (11%), fenestrated CMDs (70%) and off-the-shelf T-Branch device (17%) were used with a median number of branches/fenestrations of 4 (IQR, 3-4). SVS classification of implantation zones were determined as follows: 9 (6%) zone 2, 21 (20%) zone 3, 26 (18%) zone 4 and 89 (61%) zone 5. SCI was present in 8 patients (5.5%) and classified according to the SVS SCI grading system as follows: 1 grade 1, 5 grade 2 and 2 grade 3a. When evaluating implantation zone independently of coverage length and patency of collateral beds, a high implantation zone (1-4) was not associated with SCI (P = 0.9). Similarly, prophylactic spinal drain did not demonstrate association with the occurrence of SCI (3[9%] vs. 5[4%], with and without spinal drain, respectively) (P = 0.3). For patients with high implantation zones, staged repair was performed in 38 patients (26%) at a median time of 2 months (IQR, 2-6 months). Among these patients, the frequency of SCI was 13%. Staged repair was associated with an 80% reduction in the frequency of SCI (OR, 0.19 [95% CI, 0.04-0.084]) (P = 0.02).

CONCLUSION

F-BEVAR can be performed with a minimal risk of SCI without the need for routine prophylactic spinal drains. High implantation zones did not predict SCI after F-BEVAR; however, staged repair significantly decreased the risk of SCI after F-BEVAR.

Ischemic spinal cord injury - experimental evidence and evolution of protective measures

BACKGROUND

Paraplegia remains one of the most devastating complications of descending and thoracoabdominal aortic repair. The aim of this review is to outline the current state of art in the rapidly developing field of spinal cord injury (SCI) research.

METHODS

A review of PubMed and Web of Science databases was performed using the following terms and their combinations: spinal cord, injury, ischemia, ischemia-reperfusion, ischemic spinal cord injury, paraplegia, paraparesis. Articles published before July 2019 were screened and included if considered relevant.

RESULTS

The review focuses on the topic of SCI and the developments concerning methods of monitoring, diagnostics and prevention of SCI.

CONCLUSIONS

Translation of novel technologies from bench to bedside and into everyday clinical practice is challenging, however each of the developing areas hold great promise in SCI prevention.

Aneurysms and dissections - What is new in the literature of 2019/2020 - a European Society of Vascular Medicine annual review

More than 6,000 publications were found in PubMed concerning aneurysms and dissections, including those Epub ahead of print in 2019, printed in 2020. Among those publications 327 were selected and considered of particular interest.

Early Renal Function Alterations in Renal Branches vs. Renal Fenestrations - A Dynamic Scintigraphy Based Prospective Study

OBJECTIVE

The objective of this prospective single centre study was to assess whether branches and fenestrations have different outcomes on renal function in the early phase.

METHODS

From March 2018 to June 2019, 67 patients who underwent elective fenestrated and branched endovascular aneurysm repair (F/BEVAR) procedures were enrolled in this study. The patients were divided into two groups according to the renal bridging component configuration (fenestration vs. branch). All of them underwent dynamic renal scintigraphy with ^99mTc diethylenetriaminepentaacetic acid (DTPA), two weeks pre-operatively, and three months and one year post-operatively. The primary end points were peri-procedural technical success, 30 day major adverse events, differences in glomerular filtration rate (GFR) between the branch and fenestration configurations, and variations between the pre-operative and the post-operative dynamic renal scintigraphy.

RESULTS

Overall, 135 kidneys were analysed: 63 in the 32 patients treated with fenestrations, and 72 in the 35 patients treated with branches; the mean GFR on baseline scintigraphy was 58.4 ± 30.9 mL/min in the fenestration group, and 65.1 ± 29.2 mL/min in the branch group. Only kidneys associated with a patent fenestration/branch were included in the split GFR final analysis. The mean total GFR at three month scintigraphy decreased by 6.0 ± 2.9 mL/min in the fenestration group and by 23.4 ± 6.4 mL/min in the branch group. The split GFR decreased by 3.5 ± 0.6 mL/min in the fenestration group, and by 15.4 ± 5.4 mL/min in the branch group. The GFR decrease remained stable at one year.

CONCLUSION

In this study, the use of branches for renal arteries during F/BEVAR resulted in a greater decrease in the GFR than in those patients who were treated with fenestrations alone. The scintigraphic alterations were evident at an early phase.

Geometrical Evaluation of Aortic Sac Remodeling During Two-Step Thoracoabdominal Aortic Aneurysm Endovascular Repair

BACKGROUND

The present study evaluates aneurysmal sac remodeling and the loss of the intercostal arteries after the first step of staged treatment of thoracoabdominal aortic aneurysms (TAAAs). The purpose of this approach is to keep the aneurysmal sac temporarily perfused to induce progressive thrombosis of the aneurysm while simultaneously allowing the spinal cord to establish adequate perfusion thereby promoting the development of collateral circulation.

METHODS

All patients with type II or type III TAAAs, having undergone 2-step endovascular treatment with at least a 2-branch endoprosthesis at our institution between April 2017 and May 2019, were retrospectively evaluated. Thirty-day mortality and spinal cord ischemia was assessed. The mean number of the intercostal and lumbar arteries, coverage length between the left subclavian artery and the stent graft proximal landing zone, total volume of the aneurysmal sac, lumen volume, and thrombosis volume were measured by preoperative and first-step postoperative computed tomography angiography. Patients were also grouped based on the chosen endoprosthesis (group A: double-branch aneurysmal sac reperfusion; group B: single-branch aneurysmal sac reperfusion).

RESULTS

Eleven patients (mean age: 76.5 years; range: 61-86) were considered. No 30-day mortality was observed after the first-step procedure, and 1 patient died after second-step treatment. No permanent paraplegia was observed after either the first or second endovascular steps. The lumen volume significantly decreased (27%; P < 0.001) after first-step endovascular treatment although there was a significant increase in aneurysm thrombosis (34% to 54%). The mean number of the intercostal arteries decreased from 19.7 to 9.3 (P < 0.001) after first-step endovascular treatment. Volume variations and percentage of intercostal loss did not significantly differ between the 2 groups.

CONCLUSIONS

Although aneurysm volume continued to increase after first-step treatment, two-step endovascular treatment is a feasible alternative to reduce the risk of severe ischemia in patients with extended TAAAs.

Late failure of a Nellix endoprosthesis treated with the t-Branch off-the-shelf multibranched stent graft

A 66-year-old man arrived at our emergency department 3 years after an endovascular aneurysm sealing procedure performed at another center. Computed tomography angiography showed distal migration of a Nellix endoprosthesis (Endologix, Irvine, Calif) and a posterior contained rupture. The left kidney was excluded by an occluded iliac-left renal bypass, which was performed at the time of the Nellix implantation because of unintended coverage. A t-Branch (Cook Medical, Bloomington, Ind) was implanted in an emergency, but the delivery caused disruption of the Nellix limb, requiring relining. Target vessels were bridged with VBX stents (W. L. Gore & Associates, Flagstaff, Ariz). The postoperative course was uneventful except for renal function impairment that was restored 2 weeks later.