The Combined Use of a Distal Self-Expandable and Proximal Balloon-Expandable Stent Graft in Bridging Hostile Renal Arteries in Thoracoabdominal Branched Endografting

Expert-Based Narrative Review on Contemporary Use of an Off-The-Shelf Multibranched Endograft for Endovascular Treatment of Thoracoabdominal Aortic Aneurysms: Device Design, Anatomical Suitability, Technical Tips, Perioperative Care, Clinical Applications, and Real-World Experience

Advanced endovascular techniques, such as fenestrated stent grafts, are nowadays available that permit minimally invasive treatment of complex abdominal aortic aneurysms. However, thoracoabdominal aortic aneurysm patients have anatomic limitations to fenestrated stent-grafts given a large lumen, that is, the gap between the endograft and the inner aortic wall. This has led to the development of branched endovascular aneurysm repair as the ideal option for such patients. The Zenith t-Branch multibranched endograft (Cook Medical, Bloomington, IN), which has been commercially available in Europe to treat thoracoabdominal aortic aneurysm since June 2012, represents a feasible off-the-shelf alternative for treatment of such pathologies, especially in the urgent setting, for patients who cannot wait the time required for manufacturing and delivery of custom-made endografts. The device's anatomical suitability should be considered, especially for female patients with smaller iliofemoral vessels. Several tips may help deal with particularly complex scenarios (such as, for instance, in case of narrow inner aortic lumens or when treating patients with failure of prior endovascular aneurysm repair), and a broad array of techniques and devices must be available to ensure technical and clinical success. Despite promising early outcomes, concerns remain particularly regarding the risk for spinal cord ischemia and further assessment of long-term durability is needed, including the rate of target vessel instability and need for secondary interventions. As the published evidence mainly comes from retrospective registries, it is likely that reported outcomes may suffer from an intrinsic bias as most procedures reported to date have been carried out at high-volume aortic centers. Nonetheless, with the never-ceasing adoption of new and refined techniques, outcomes are expected to ameliorate.

The Impact of Target Vessel Anatomy and Bridging Stent Geometry on Branched Endovascular Aortic Repair Outcomes

OBJECTIVE

This study aimed to evaluate the impact of target vessel anatomy and bridging stent geometry on target vessel instability in branched endovascular aortic repair (B-EVAR).

METHODS

This retrospective, single centre cohort study included all consecutive B-EVARs performed between September 2018 and December 2022 for thoraco-abdominal aortic aneurysm (TAAA) or complex abdominal aortic aneurysm (CAAA). The primary endpoints were target vessel instability and related re-interventions at 12 months. Secondary endpoints were 30 day results, including target vessel instability and re-interventions. Target vessel instability analysis consisted of assessment of target vessel anatomy, including diameter, aortic trunk to branch angle, and tortuosity. Post-operative parameters included change of clock position/horizontal misalignment, bridging length (gap), sealing length, tortuosity, post-stenting angle, and oversizing ratio.

RESULTS

A total of 69 patients (TAAA: n = 56, 81%; CAAA: n = 13, 19%) and 271 (133 visceral and 138 renal) target vessels were included. The cumulative incidence of target vessel instability was 4.8%, 6.4%, and 7.9% at one, two, and three years, respectively. In the renal target vessel group, vessel diameter ≤ 4 mm (hazard ratio [HR] 1.28, 95% confidence interval [CI] 1.116 - 2.54; p = .022) and a bridging length ≥ 25 mm (HR 1.320, 95% CI 1.066 - 1.636; p = .011) were associated with increased target vessel instability. In visceral vessels, a change in clock position/horizontal misalignment ≥ 70 minutes (HR 1.072, 95% CI 1.026 - 1.121; p = .002) showed a significant association with target vessel instability.

CONCLUSION

Target vessel diameter, bridging length (gap), and horizontal misalignment seemed to be associated with adverse target vessel outcomes. This may be solved with more customised endograft solutions to reduce the negative impact of the latter parameter.

Systematic Review and Meta-analysis of Short-term and Mid-term Outcomes After Use of t-Branch Off-the-shelf Multibranched Endograft for Elective and Urgent Treatment of Thoracoabdominal Aortic Aneurysms

OBJECTIVE

To conduct a meta-analysis to assess the safety and efficacy of t-Branch off-the-shelf multibranched endograft for the treatment of thoracoabdominal aortic aneurysm (TAAA).

DATA SOURCES

PubMed, Embase, and Web of Science.

REVIEW METHODS

Online databases were searched from June 2012 to March 2023. The data were pooled together using a random-effects model of proportions. The outcomes overall included technical success, spinal cord ischemia, target vessel occlusion, type I or III endoleak, reintervention, early mortality (30-day), and mid-term outcomes. Subgroup meta-analyses and meta-regression were performed to explore variation among studies.

RESULTS

A total of 15 studies containing 1238 patients were included in the meta-analysis. The overall study quality assessment was found to be moderate to good. The pooled technical success was 97.0% (95% confidence interval [CI]=95.5-98.6, I2=53.01%, 1185/1238 cases, 15 studies). Overall, early mortality was 7.3% (95% CI=4.4-10.1, I2=74.48%, 124/1238 cases, 15 studies). Early spinal cord ischemia was 13.4% (95% CI=9.6-17.2, I2=67.24%, 160/1238 cases, 15 studies), and early type I or III endoleak was 6.0% (95% CI=3.4-8.5, I2=53.71%, 68/1032 cases, 9 studies). Mid-term outcomes showed target vessel occlusion was 4% (95% CI=1.4-6.5, I2=65.18%, 28/528 cases, 10 studies, 5-21.2 months), type I or III endoleak was 4.7% (95% CI=2-7.5, I2=49.74%, 38/512 cases, 10 studies, 5-21.2 months), reintervention was 11.2% (95% CI=8.1-14.3, I2=31.06%, 85/650 cases, 10 studies, 5-21.2 months), and pooled mortality was 13.9% (95% CI=7.2-20.7, I2=76.32%, 84/550 cases, 11 studies, 5-21.2 months). Meta-regression found a significant linear association between higher technical success and earlier publication year (p=0.014) and studies with anatomic inclusion criteria (p=0.037). Urgent patients (p=0.021) and later publication year (p=0.048) were significantly associated with higher early mortality.

CONCLUSION

The use of the off-the-shelf t-Branch multibranched endograft for elective or urgent endovascular TAAA repair is associated with high technical success rates and proved to be safe and effective at early and mid-term follow-up. However, the heterogeneity between the included studies is high, and prospective, randomized studies along with future larger studies with long-term follow-up are needed.

CLINICAL IMPACT

The Zenith t-Branch (Cook Medical, Bloomington, Ind) was approved as a commercially available device in Europe in June 2012. Although a decade has past, the outcomes of t-Branch have rarely been synthesized at the global level. This meta-analysis included 15 studies containing 1238 patients. The meta-analyses included technical success, major adverse events, reintervention, early mortality, and mid-term outcomes. The outcome was very meaningful and representative for the use of t-Branch. It is helpful for endovascular surgeons to make decisions on the treatment of TAAA patients.

Effect of bridging stent graft selection for directional branches on target artery outcomes of fenestrated-branched endovascular aortic repair in the United States Aortic Research Consortium

OBJECTIVE

The purpose of this study was to evaluate the effect of directional branches (DBs) bridging stent choice on target artery (TA) outcomes during fenestrated-branched endovascular repair of complex abdominal and thoracoabdominal aortic aneurysms.

METHODS

Patients enrolled in nine prospective physician-sponsored investigational device exemption studies in the United States between 2005 and 2020 were analyzed. All patients who had at least one TA incorporated by DB using either self-expandable (SESGs), balloon-expandable (BESGs), or hybrid stent graft combinations (HSGs). Endpoints were TA patency and freedom from TA endoleak, instability, and reintervention.

RESULTS

There were 800 patients with 2426 renal-mesenteric arteries incorporated by DBs. DB stent selection was SESGs in 1205 TAs (50%), BESGs in 1095 TAs (45%), and HSGs in 126 TAs (5%). SESGs were predominantly used in the first three quartiles of the study period, whereas BESGs comprised 75% of all stents between 2017 and 2020. The median follow-up was 15 months (interquartile range, 6-35 months). At 5 years, BESGs had significantly lower freedom from TA instability (78% ± 4% vs 88% ± 1% vs 96% ± 2%; log-rank P =.010), freedom from TA endoleaks (87% ± 3% vs 97% ± 1% vs 99% ± 1%; log-rank P < .001), and freedom from TA reintervention (83% ± 4% vs 95% ± 1% vs 99% ± 2%; log-rank P <.001) compared with SESGs or HSGs, respectively. For renal arteries, there was no difference in freedom from TA instability for BESGs, SESGs, or HSGs. However, freedom from TA endoleaks and reintervention were lower for renal arteries targeted by BESGs compared with DBs targeted by SESGs and HSGs (83% ± 6% vs 98% ± 1% vs 100%; log-rank P < .001; and 70% ± 10% vs 92% ± 1% vs 96% ± 4%; log-rank P = .022). For mesenteric arteries, DBs targeted by BESGs had lower freedom from TA instability, endoleak, and reintervention than SESGs or HSGs. In stent-specific analysis, iCAST BESGs had the lowest freedom from TA instability either for renal or mesenteric arteries, primarily due to higher rates of TA endoleaks. There was no difference in patency in any scenario. Independent predictors of TA instability were age (+1-year: hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.94-0.99), stent diameter (+1 mm: HR, 0.67; 95% CI, 0.57-0.80), and BESG (HR, 1.8; 95% CI, 1.1-2.9).

CONCLUSIONS

DBs incorporated using BESGs had lower freedom from TA instability, TA endoleak, and TA reintervention compared with SESGs and HSGs. The patency of DBs was not affected by the type of stent construction. The observed performance disadvantage associated with BESGs appears to have largely been driven by iCAST usage.

Midterm results on a new self-expandable covered stent combined with branched stent grafts: Insights from a multicenter Italian registry

OBJECTIVE

To investigate the technical periprocedural and midterm outcomes of endovascular repairs with multibranched endovascular repair or iliac branch devices combined with a new self-expanding covered stent.

METHODS

The COvera in BRAnch registry is a physician-initiated, multicenter, ambispective, observational registry (ClinicalTrials.gov Identifier: NCT04598802) enrolling patients receiving a multibranched endovascular repair or iliac branch devices procedure mated with Bard Covera Plus (Tempe, AZ) covered stent, designed to evaluate the outcomes of the covered stent mated with patient-specific and off-the-shelf branched stent graft. Primary end points were technical success, branch instability, and freedom from aortic and branch-related reintervention within 30 days and at follow-up. Preoperative characteristics, comorbidities, and outcomes definitions were graded according to the Society for Vascular Surgery reporting standards.

RESULTS

Two hundred eighty-four patients (76 years; range, 70-80 years; 79% males) in 24 centers were enrolled for a total of 708 target vessels treated. The covered stents were mated with an off-the-shelf graft in 556 vessels (79%) and a custom-made graft in 152 (21%). Three hundred seven adjunctive relining stents in 277 vessels (39%) were deployed, of which 116 (38%) were proximal, 66 (21%) intrastent, and 125 (41%) distal. Adjunctive relining stent placement was more frequent when landing in a vessel branch instead of the main trunk (59% vs 39%; P = .031), performing a percutaneous access (49% vs 35%; P < .001), using a stent with a diameter of 8 mm or greater (44% vs 36%; P = .032) and a length of 80 mm or greater (65% vs 55%; P = .005), when a post-dilatation was not performed (45% vs 29%; P < .001) and when an inner branch configuration was used (55% vs 35%; P < .001). Perioperative technical bridging success was 98%. Eight patients (3%) died in the perioperative period. Two deaths (1%) were associated with renal branch occlusion followed by acute kidney injury and paraplegia. Follow-up data were available for 638 vessels (90%) at a median of 32 months (Q1, Q3, 21, 46). Branch instability was reported in 1% of branches. Forty-six patients (17%) died during follow-up, nine (3%) of them owing to aortic-related causes. Primary patency rates at 1, 2, and 3 years were 99% (581/587), 99% (404/411), and 97% (272/279), respectively. Branch instability was associated with patient-specific devices (9% vs 4%; P = .014) and intrastent adjunctive stent placement (12% vs 2%; P = .003), especially when a bare metal balloon-expandable stent was used (25% vs 3%; P < .001).

CONCLUSIONS

The use of this new self-expanding covered stent mated with branched endografts proved to be safe and feasible with high technical procedural success rates. Low rates of branch instability were observed at midterm follow-up. Comparative studies with other commercially available covered stents are warranted.

Outcomes of Directional Branches of the T-Branch Off-the-Shelf Multi-Branched Stent-Graft

Background: A controversy on bridging covered stent (BCS) choice, between self-expanding (SECS) and balloon-expandable (BECS) stents, still exists in branched endovascular repair. This study aimed to determine the primary target vessel (TV) patency in patients treated with the t-Branch device and identify factors impairing the outcomes. Methods: A retrospective study was undertaken, including patients treated with the t-Branch (Cook Medical, Bloomington, IN, USA) between 2014 and 2019 (early 2014–2016; late 2017–2019). The endpoint was the primary patency (CT: celiac trunk, SMA, superior mesenteric artery, RRA: right renal artery, LRA: left renal artery) during the follow-up. Any branch instability event was assessed. The factors affecting the patency were determined using multivariable regression models and Kaplan–Meier analyses. Results: In total, 2018 TVs were analyzed; 1542 SECSs and 476 BECSs. The CT patency was 99.8% (SE 0.2%) at the 1st month, with no other event. The SMA patency was 97.8% (SE 1) at the 12th month. The RRA patency was 96.7% (SE 2) at the 24th month. The LRA patency was 99% (SE 0.4) at the 6th month. Relining was the only factor independently associated with the SMA patency (OR 8.27; 95% CI 1.4–4.9; p = 0.02). The freedom from instability was 62% (SE 4.3%) and 45% (SE 5.4%) at the 24th month and 36th month. No significant difference was identified between the BECSs and SECSs in the early or late experience. Conclusion: BCS for the t-Branch branches performed with a good primary patency during the short-term follow-up. The type of BCS did not influence the patency. Relining might be protective for SMA patency.

Meta-analysis of Comparative Studies Between Self- and Balloon-Expandable Bridging Stent Grafts in Branched Endovascular Aneurysm Repair

PURPOSE

Currently there is no robust evidence which type of bridging stent graft provides better outcomes after branched endovascular aortic repair (BEVAR). Self-expanding (SESG) and balloon-expandable (BESG) stent grafts are both commonly used to connect branches to their respective target vessels (TV). The aim of the current review was to evaluate the impact of the type of bridging stent grafts on TV outcomes during the mid-term follow-up after BEVAR.

MATERIALS AND METHODS

The study protocol was registered to the PROSPERO (CRD42021274766). A search of the English literature was conducted, using PubMed and EMBASE databases via Ovid and Cochrane database via CENTRAL, from inception to June 30, 2021, using the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. Only comparative studies on BEVAR reporting TV outcomes related to BESG vs SESG were considered eligible. Individual studies were assessed for risk of bias using the Newcastle Ottawa Scale. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach was used to evaluate the quality of evidence. The primary outcomes were primary patency, freedom from endoleak, TV instability, and re-intervention between BESG and SESG, used as bridging stents in branches. The outcomes were summarized as odds ratio along with their 95% confidence intervals (CI), through a paired meta-analysis.

RESULTS

Five out of 609 articles published from 2016 to 2020 were included in the analysis. In total, 1406 TV were revascularized, 547 (38.9 %) with BESGs and 859 with SESGs. The overall pooled primary patency (odds ratio [OR], 0.40; 95% confidence interval [CI], 0.29-1.09; p=.256, I²=4.24%) and freedom from branch-related endoleak (OR, 0.65; 95% CI, 0.17-1.48; p<.122, I²=0.18%) did not differ between the stent types during the available follow-up (17 months, range = 12-35 months). In 4 studies (619 TV), SESG required fewer secondary interventions (OR, 1.04; 95% CI, 0.23-1.83; p=.009, I²=0%) and TV instability rate was lower (OR, 0.99; 95% CI, 0.33-1.65; p=.003, I²=0%) compared with BESG during the available follow-up.

CONCLUSION

BESG and SESG seem to perform similarly in terms of primary patency and branch-related endoleak during the mid-term follow-up. Current data from retrospective studies suggest that overall TV instability and re-intervention rates are favorable for SESG as bridging stent grafts in BEVAR.

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.

Parallel Graft to Preserve a Reimplanted Inferior Mesenteric Artery During Thoracoabdominal Multibranched Endografting

INTRODUCTION

Preserving pelvic circulation is crucial to minimize the risk of spinal cord and colonic ischemia, especially during the endovascular treatment of extended thoraco-abdominal aneurysm (TAAA) after previous open repair (OR).

CASE REPORT

A 78-years-old patient, previously treated for AAA with OR and reimplantation of inferior mesenteric artery (IMA), has presented with 9 cm type-III TAAA and underwent to a multi-stage endovascular procedure. Two thoracic endografts, t-Branch and a straight endograft by Cook Zenith platform were deployed. Renal and superior mesenteric arteries were cannulated and revascularized. Through the left axillary access, a 5F-vertebral catheter was delivered over a 0.035 inch guidewire to selectively catheterize IMA. A post-anastomotic stenosis was stented to advance the sheath and the parallel-graft (Viabahn 7 × 150 mm, Gore) into the artery. Thus, a bifurcated endograft was deployed inside the previous OR. According to the Sandwich-Technique, the stentgraft was deployed parallel and outside the bifurcated device, inside the straight one and 2 cm into the IMA and then reinforced by a bare-metal-stent (Protégé EverFlex™ 7 × 120 mm, Medtronic). Finally, a kissing ballooning of iliac endografts and parallel-graft was performed. The procedure was completed five days later, by stenting the celiac trunk. Post-operative course was uneventful. The 36-months CTA showed the patency of the IMA with no complications.

CONCLUSION

The combination of t-Branch and Sandwich-Technique for IMA could be employed to treat extended TAAA with previous OR and reimplanted IMA thus minimizing the risk of colonic and spinal cord ischemia.

Intracranial Hemorrhage After Endovascular Repair of Thoracoabdominal Aortic Aneurysm

BACKGROUND

Intracranial hemorrhage (ICH) is a rare but devastating complication of thoracoabdominal aortic aneurysm (TAAA) repair with fenestrated/branched endograft (f/bEVAR). The cerebrospinal fluid drainage (CSFD) is considered one of the leading causes; however, other possible concomitant factors have not been individualized yet. The aim of the present work was to evaluate the pattern of ICH events after f/bEVAR for TAAA and to identify possible associated factors.

MATERIALS AND METHODS

All f/bEVAR procedures for TAAA performed in a single academic center from 2012 to 2020 were evaluated. ICH was assessed by cerebral computed tomography if neurological symptoms arose. Pre-, intra-, and postoperative characteristics were analyzed in order to identify possible factors associated.

RESULTS

A total of 135 f/bEVAR were performed for 72 (53%) type I, II, III and 63 (47%) type IV TAAA; 74 (55%) were staged procedures, 101 (73%) required CSFD, and 24 (18%) were performed urgently. The overall 30-day mortality was 8% (5% in elective cases); spinal-cord ischemia occurred in 11(8%) and ICH in 8 (6%) patients. All ICH occurred in patients with CSFD. ICH occurred intraoperatively in 1 case, inter-stage in 4 and after F/BEVAR completion in 3, after a median of 6 days the completion stage. Three (38%) of 8 patients with ICH died at 30 days and ICH was associated with 30-day mortality: odds ratio (OR) 13.2, 95% confidence interval (CI): 2.3-76, p=0.01. The analysis of the perioperative characteristics identified platelet reduction >60% (OR 11, 95% CI 1.6-77, p=0.03), chronic kidney disease (16% vs 0%, p=0.002), and total volume of liquor drained >50 mL (OR 8.1, 95% CI 1.1-69, p=0.03) as associated with ICH.

CONCLUSIONS

Current findings may suggest that ICH is a potential lethal complication of the endovascular treatment for TAAAs and it mainly occurs in patients with CSFD. High-volume liquor drainage, platelet reduction, and chronic kidney disease seems increase significantly the risk of ICH and should be considered during the perioperative period and for further studies.

Reinterventions after fenestrated and branched endografting for degenerative aortic aneurysms

OBJECTIVE

Fenestrated/branched endovascular abdominal aortic aneurysm repair (F/B-EVAR) is widely accepted technique to treat juxta/pararenal abdominal aortic aneurysms (J/P-AAAs) and thoracoabdominal aortic aneurysms (TAAAs) for patients at high-surgical risk. However, the follow-up results should be carefully evaluated, especially in terms of the reintervention rate. The aim of the present study was, therefore, to evaluate the early and mid-term reinterventions after FB-EVAR for J/P-AAAs and TAAAs and their effects on follow-up survival.

METHODS

From 2006 to 2019, all consecutive patients who had undergone F/B-EVAR for J/P-AAAs or TAAAs were prospectively enrolled. Cases requiring reinterventions were retrospectively analyzed. Patients with aortic dissection were excluded from the present analysis. Reinterventions were classified as follows: access related, aortoiliac related, or target visceral vessel (TVV) related. Freedom from reintervention and survival were assessed using the Kaplan-Meier method, and univariate and multivariate analyses were used to determine the risk factors.

RESULTS

Overall, 221 F/B-EVAR procedures were performed for 111 J/P-AAAs (50.3%) and 110 TAAAs (49.7%) in an elective (182; 82%) or urgent (39; 18%) setting. The median follow-up was 27 months (interquartile range, 13 months). Overall, 41 patients had undergone 52 reinterventions (single, 30 [14%]; multiple, 11 [5%]; access related, 17 [33%]; aortoiliac related, 6 [12%]; TVV related, 29 [55%]). Of the 52 reinterventions, 32 (62%) and 20 (38%) had occurred within and after 30 days, respectively. Eight reinterventions (15%) had been were performed in an urgent setting. Endovascular and open reinterventions were performed in 32 (62%) and 20 (38%) cases, respectively. Open reinterventions were frequently access related (access, 16; no access, 4; P ≤ .001). Technical success was 95% (39 patients); failures consisted of one splenic artery rupture and one renal artery loss. Patients undergoing reintervention had more frequently undergone a primary urgent F/B-EVAR (urgent, 12 of 39 [31%]; elective, 29 of 182 [16%]; P < .001) and had had TAAAs (TAAAs, 34 of 41 [83%]; J/P-AAAs, 7 of 41 [17%]; P < .001). The patients with TAAAs had had a greater incidence of TVV-related reintervention (TAAAs, 26 of 28 [93%]; J/P-AAAs, 2 of 28 [7%]; P < .001) and multiple reinterventions (TAAAs, 9 of 11 [82%]; J/P-AAAs, 2 of 11 [18%]; P = .03) compared with those with J/P-AAAs. Survival at 3 years was 75%. Freedom from reintervention was 81% at 3 years. Patients who had undergone reinterventions had lower 3-year survival (reintervention, 61%; no reintervention, 77%; P = .02). Preoperative chronic renal failure (hazard ratio [HR], 2.0; 95% confidence interval [CI], 1.1-3.6; P = .02), TAAAs (HR, 2.3; 95% CI, 1.1-4.8; P = .03), and urgent primary F/B-EVAR procedures (HR, 2.5; 95% CI, 1.2-4.9; P = .01) were independent predictors of late mortality.

CONCLUSIONS

Reinterventions after F/B-EVAR are not uncommon and were related to TVVs in only one half of cases. Most of them can be performed in an elective setting using endovascular techniques. The technical success rate was excellent. Reinterventions were more frequent after TAAAs and urgent F/B-EVAR procedures and had a significant effect on overall survival in these situations.

Geometric Analysis to Determine Kinking and Shortening of Bridging Stents After Branched Endovascular Aortic Repair

Purpose

To evaluate bridging stent geometry in patients who underwent branched endovascular aortic repair (B-EVAR) and to correlate the outcomes with intrinsic bridging stent characteristics aiming to identify the stent(s) that guarantees the best performance.

Methods

Pre-operative and post-operative computed tomography images of all patients undergoing B-EVAR between September 2016 and April 2019 were retrospectively analyzed. Following geometrical features were measured: target vessel take-off angle (TOA); longitudinal stent shortening; shape index (SI), intended as ratio between minimum and maximum diameter of the lumen cross sections, averaged on three segments: zone 1 (proximal stented zone), zone 2 (intermediate), and zone 3 (distal).

Results

Thirty-eight branches (8 right (RRA) and 8 left renal arteries (LRA), 11 superior mesenteric arteries (SMA), 11 celiac trunks (CTR)) were treated. Fluency (Bard Peripheral Vascular), COVERA (Bard Peripheral Vascular), and VBX (WLGore&Assoc) stent-grafts were implanted in 10, 12, and 16 branches, respectively. Pre-operative TOA was more acute in RRA and LRA when compared to CTR and SMA, and straightened in post-operative configuration (109.86 ± 28.65° to 150.27 ± 21.0°; P < 0.001). Comparable values of SI among the stent types were found in zone 1 (P = 0.08), whereas higher SI in VBX group was detected in zones 2 (P < 0.001) and 3 (P < 0.001). The VBX group was also the most affected by stent shortening (11.12 ± 5.65%; P = 0.001).

Conclusion

Our early experience showed that the VBX stent offers greater stent circularity than the other devices even if a greater shortening has been observed drawing attention with regards to the decision of the nominal stent length.