The "Bundle Wire" Technique: A Novel Approach to Cannulating Challenging Target Vessels Using Multiple Fine Atraumatic Guidewires That Together Serve as a Stiff Guidewire

PURPOSE

To present a novel technique that enables safe and effective cannulation of target vessels with challenging anatomy during fenestrated/branched endovascular aortic repair (F/B-EVAR).

TECHNIQUE

Following deployment of the F/B-EVAR endograft, the target vessels (TVs) are cannulated. The bundle wire technique provides a solution to challenging TVs and uses multiple fine atraumatic guidewires that together serve as a stiff guidewire. The technique can be executed in 2 ways using: (1) one 0.018 inch and one 0.014 inch guidewire or (2) three 0.014 inch guidewires. We demonstrate the technique in a case of a complex abdominal aortic aneurysm treated using branched EVAR in which the left renal artery with severe ostial stenosis was catheterized using the bundle wire technique.

CONCLUSIONS

The bundle wire technique offers a technically feasible and economically viable solution for facilitating catheter and bridging stent delivery in anatomically challenging TVs during F/B-EVAR. It is a useful addition to the therapeutic armamentarium available to physicians for accessing demanding TVs.

A novel balloon-assisted technique to secure visceral catheterization during a chimney endovascular repair of a ruptured abdominal aortic aneurysm in a centenarian patient

A 100-year-old male patient was admitted with a ruptured abdominal aortic aneurysm due to type IA endoleak. Given the proximity of the ruptured site to the superior mesenteric artery (SMA) and renal arteries, a ChEVAR was indicated. Catheterization of the target visceral vessels was a challenging procedural step because of an intensely tortuous thoracic aorta. This hostile aortic anatomy also inhibited exchange for a super stiff guide-wire and selective cannulation with the diagnostic catheter was repeatedly lost when guidewire exchange was attempted. To overcome this issue, a 5 x 40 mm balloon catheter was placed 3cm into the target arteries. The balloon was then inflated below the nominal pressure limit enabling safe exchange for a super stiff guidewire and placement of three 90-cm long 7Fr guiding sheaths. The procedure was thus safely performed with deployment of an aortic extension and the bridging stents.

Ascending Aorta Nose-Cone Loop Technique as Bail Out for Precise Branched Endovascular Aortic Arch Endograft Delivery Without Valve Re-Crossing

PURPOSE

To describe a right carotid-femoral through-and-through (T&T) guidewire technique during branched thoracic endovascular aortic arch repair (B-TEVAR) to facilitate endograft delivery in a very tortuous aortic anatomy for a type Ia endoleak (EL) of a previous aortic endograft implantation.

TECHNIQUE

AT&T guidewire was established between the right common carotid artery and the right common femoral artery to facilitate a difficult endograft delivery. Once in the aortic arch, a loop in the ascending aorta was formed to allow the endograft to reach the desired position without losing tension on the guidewire. This maneuver allowed the T&T guidewire to be kept in place until the desired position was reached. The nose-tip of the endograft was curved over the looped guidewire pointing toward the innominate artery without crossing the valve. After endograft deployment, the T&T guidewire was released, and the branches were bridged in a standard fashion. Completion angiography documented correct deployment of the endograft and no sign of type I/III EL. The 1-month computed tomography angiography confirmed the correct deployment.

CONCLUSION

Carotid-femoral T&T guidewire to facilitate endograft delivery in difficult anatomies can be feasible even in B-TEVAR. Possible bailout maneuvers are available if the aortic valve needs to be crossed after endograft delivery.

CLINICAL IMPACT

Endovascular arch repair gains popularity as a valuable alternative, especially in patients considered unfit for open repair. A through-and-through (T&T) guidewire for endovascular arch repair with a landing zone in zone 0 according to Ishimaru is usually performed through the externalization of the femoral guidewire through a transapical access, but this may not always be feasible in frail patients. A right carotid-femoral though-and-through guidewire with a loop formation in the ascending aorta is proposed to achieve the support of a T&T wire to pass tortuous aortoiliac anatomies and access the ascending aorta without the need for aortic valve crossing.

Five-year outcomes of physician-modified endografts for repair of complex abdominal and thoracoabdominal aortic aneurysms

OBJECTIVE

There is paucity of data on the durability of physician modified endografts (PMEGs) for complex abdominal (CAAAs) and thoracoabdominal aortic aneurysms (TAAAs) despite widespread use. The aim of this study was to evaluate and compare the early and long-term outcomes of fenestrated-branched endovascular aortic repair (FB-EVAR) for CAAAs and TAAAs using PMEGs.

METHODS

We reviewed clinical data and outcomes of patients treated by FB-EVAR using PMEGs for CAAAs (defined as short-neck infrarenal, juxtarenal, and pararenal AAAs) and TAAAs between 2007 and 2019. All patients were treated by a dedicated team with extensive manufactured device experience. Endpoints included 30-day mortality and major adverse events, patient survival and freedom from aortic-related mortality (ARM), freedom from secondary intervention, target artery (TA) patency, and freedom from TA endoleak and TA instability.

RESULTS

Of 645 patients undergoing FB-EVAR, 156 patients (24%) treated with PMEG (121 males; mean age, 75 ± 8 years) were included. There were 89 CAAAs, 33 extent IV TAAAs and 34 extent I to III TAAAs. A total of 452 renal-mesenteric targets (3.1 ± 1.0 vessels/patient) were incorporated. Patients with TAAAs had significantly (P < .05) larger aneurysms (73 ± 11 vs 68 ± 14 mm), more TAs incorporated (3.4 ± 0.9 vs 2.8 ± 1.0), and more often had previous aortic repair (54% vs 27%). Technical success was higher in patients treated for CAAAs (99% vs 91%; P = .04). Thirty-day and/or in-hospital mortality was 5.7% and was significantly lower for CAAAs compared with TAAAs (2% vs 10%; P = .04), with three of nine early mortalities (33%) among patients treated emergently. After a mean follow-up of 49 ± 38 months, there were 12 aortic-related deaths (7.6%), including nine early deaths (5.7%) from perioperative complications and three late deaths (1.9%) from rupture. At 5 years, patient survival was 41%. Patients treated for CAAAs had higher 5-year freedom from ARM (P = .016), TA instability (P = .05), TA endoleak (P = .01), and TA secondary interventions (P = .05) with a higher, but non-significant, freedom from sac enlargement ≥5 mm (P = .11). Primary and secondary TA patency was 91% ± 2% and 99% ± 1%, respectively. Sac regression ≥5 mm occurred in 67 patients (43%) and was associated with increased survival (hazard ratio, 0.54; 95% confidence interval, 0.37-0.80) compared with those without sac regression.

CONCLUSIONS

FB-EVAR using PMEGs was performed with acceptable long-term outcomes. Overall patient survival was low due to significant underlying comorbidities. Patients treated for CAAAs had higher freedom from ARM, TA instability, TA endoleak, TA secondary interventions, and a trend towards higher freedom from sac enlargement compared with patients treated for TAAAs. Sac regression was associated with improved patient survival.

Postoperative Outcomes and Reinterventions Following Fenestrated/Branched Endovascular Aortic Repair in Post-Dissection and Complex Degenerative Abdominal and Thoraco-Abdominal Aortic Aneurysms

Background: The outcome of FBEVAR in post-dissection thoracoabdominal aortic aneurysms has not been well established in the literature. The aim of this study was to compare midterm outcomes following FBEVAR in post-dissection aneurysms to degenerative aneurysms. (2) Methods: This was a retrospective review of all patients undergoing FBEVAR in a single center between 2017 and 2020. The baseline characteristics, intraoperative details, and postoperative outcomes of patients with post-dissection aneurysms were compared to those with degenerative outcomes. The primary end point was unplanned reinterventions. Cox regression analysis was performed to identify the determinants of worse outcomes. Results: A total of 137 subjects with a mean age of 70 ± 10 years were included in the study, out of which 30 presented post-dissection aneurysms (22%). Custom-made devices were employed in 119 patients, off-the-shelf devices in 13 and physician-modified endografts in 5, with incorporation in 505 target vessels. The technical success rate was comparable in both groups (97% vs. 98%, p = 0.21). However, the one-year freedom from unplanned reintervention was lower in the post-dissection group (67% vs. 89%, p = 0.011). Conclusion: FBEVAR in post-dissection aneurysms is associated with a favorable technical success rate, but reintervention rates remain high. Long procedural duration and the use of adjunctive techniques are associated with increased risk of reinterventions.

Reversed and Antegrade Iliac Side Branch Stentgraft as an Alternative or Rescue Maneuver in Complex (Thoraco)Abdominal Endovascular Aortic Repair to Preserve Renal Perfusion

Purpose

To describe a technique that can preserve renal perfusion in failed bridging stent implantation of renal arteries or as intentional procedure in emergency cases, when the (thoraco)abdominal aneurysm anatomy does not meet the criteria for instructions for use of an “off-the-shelf” graft. The technique is based on reversed or antegrade integration of a standard iliac side branch graft into the aortic stentgraft system, which allows cannulation of (accessory) renal vessels.

Technique

A standard iliac side branch prosthesis is deployed and re-sheathed in reversed direction on the back table. The endograft is then implanted in the unibody in analogy to an iliac limb. The iliac side branch is cannulated followed by target vessel cannulation and covered bridging stents are deployed for completion. Furthermore, an iliac side branch prothesis can also be used to preserve relevant accessory renal arteries, when implanted in delivered antegrade loading position.

Conclusion

The use of a reversed and antegrade iliac side branch technique to revascularize renal vessels is feasible and safe in selected patients. This technique may also allow to extend the range of an “offthe- shelf” (multibranch) stentgraft, when immediate treatment is required.

Impact of gap distance between fenestration and aortic wall on target artery instability following fenestrated-branched endovascular aortic repair

OBJECTIVE

Target artery (TA) instability is the most frequent indication for secondary intervention following fenestrated and branched endovascular aortic repair (FB-EVAR) of pararenal and thoracoabdominal aortic aneurysms (TAAAs). The aim of this study was to evaluate the impact of gap distance between the endograft reinforced fenestration and TA origin at the aortic wall (fenestration gap, FG) on target-related outcomes following FB-EVAR.

METHODS

Clinical data and imaging of 430 patients enrolled in a prospective, non-randomized study to evaluate FB-EVAR using manufactured stent-grafts were reviewed. Three hundred and forty patients (79%) had >1 vessel incorporated by fenestration. FG distance was retrospectively measured on postoperative imaging and classified into three groups: no gap (FG=0 mm), FG distance 1-4 mm, and FG≥5 mm. Primary outcome was freedom from TA instability. Secondary endpoints included TA-related endoleak, TA secondary intervention, and TA patency.

RESULTS

A total of 1558 renal-mesenteric TAs were incorporated by 1104 reinforced fenestrations and 454 directional branches (DBs), with a mean of 3.9±0.5 vessels per patient. Mean FG distance was 2.8±4.5mm with FG distance of 0mm for 646 TAs, 1-4mm for 209 TAs, and ≥5mm for 249 TAs. FG distance ≥5mm was associated with significantly lower (p<.001) freedom from TA instability, type IC/IIIC endoleak, and secondary interventions at 5-years. As compared to DBs, fenestrations with FG ≥5mm had similar primary patency and freedom from TA instability, but significantly lower freedom from type IC/IIIC endoleak (91±2 vs 95±1%, log rank=0.02) and secondary interventions (87±3% vs 93±2%, log rank=0.02) at 5-years. Independent predictors of TA instability included post-dissection TAAAs (HR 2.5; 95% CI 1.2-5.4) and FG distance ≥5mm (HR 1.6; 95% CI 1.2-1.8). TAs incorporated by reinforced fenestrations had higher primary (99±0.8% vs 97±1.0%, p=.039) and secondary patency rates (100% vs 98±1.0%, p=.012) at 5-years compared DBs, with the lowest primary patency observed for renal DBs (80±6% v 92±2% p=.008).

CONCLUSION

FG distance ≥5mm was independently associated with increased risk of TA instability, type IC/IIIC endoleaks, and secondary interventions in patients treated by FB-EVAR using fenestrated designs. Targets incorporated by DBs have lower 5-year primary and secondary patency as compared to those with reinforced fenestrations, with the lowest 5-year patency of 80% for renal branches. As compared to DBs, fenestrations with FG ≥5mm carried higher risk of type IC/IIIC endoleak and secondary interventions. Independent predictors of TA instability included post-dissection TAAAs and greater FG distance, whereas dual antiplatelet therapy and larger TA diameters were protective.

Relining of infrarenal stent-graft with preloaded modified Gore Excluder for occult endoleak with sac expansion

Endoleaks remain one of the most common indications for reintervention after endovascular aortic repair. Occasionally, aneurysm sac expansion will occur in the absence of a visible endoleak or due to endotension. We describe a case of continued sac expansion without an identifiable endoleak after endovascular aortic repair. Technical challenges during the case included a short distance from the renal arteries to the flow divider and a significant metal artifact. These challenges were addressed by shortening the gate of a Gore Excluder (W.L. Gore & Associates, Flagstaff, Ariz) to the desired length. The contralateral gate was preloaded to allow for use of the snare-ride technique for gate cannulation and overcome the metal artifact that was hindering visualization.

Completion of Target Vessel Stenting After FEVAR via Snare Technique in a Patient with Tortuous Right Renal Artery

Target vessel catheterization remains challenging in patients with complex anatomies. Fenestrated endovascular aneurysm repair (FEVAR) is an established technique to treat aortic aneurysms. In this case report, we treated a juxtarenal aneurysm using FEVAR. Initial attempts to complete the target vessel stenting were unsuccessful because of an unfavorable orifice and tortuosity of the right renal artery. The completion of FEVAR was achieved with a bifemoral approach using a snare system, which aligned the tip of a steerable sheath at the level of the fenestration for the right renal artery to create a stable condition. Control angiography and computed tomography confirmed a successful stenting of the target vessel and the sealing of the fenestration without an endoleak.

Endovascular Snare Facilitates Difficult Transfemoral Target Vessel Cannulation During Fenestrated and Branched Endovascular Aortic Aneurysm Repair

We developed a novel technique using an endovascular snare system to stabilize target vessel cannulation via transfemoral access during fenestrated and branched endovascular aortic aneurysm repair (FBEVAR) in patients with challenging target vessel anatomy. This technique uses a snare, an outer sheath, and an inner delivery sheath to facilitate target vessel cannulation and stenting during FBEVAR. With the outer sheath positioned in the lower end of the partially deployed aortic graft and the delivery sheath within, a large snare is advanced through the outer sheath and over the outside of the delivery sheath until it reaches the curved portion of the delivery sheath at the level of the target vessel. The snare is then tightened to provide stability and maintain proper curvature and alignment of the delivery sheath while the target vessel is selected and stented. Following successful passage, the snare is loosened and removed from the body via the outer sheath. This snare technique is a simple, effective, and inexpensive tool that can be used for difficult target vessel cannulation during FBEVAR.

Use of Physician-Modified Fenestrated Stent-Graft With Wire Loop Technique for Complex Aortic Arch Aneurysm

BACKGROUND

To present a novel means of overcoming a deviation when treating an aortic arch aneurysm with a physician-modified fenestrated stent-graft.

METHODS

A 78-year-old man showed a rapidly expanding aortic arch aneurysm, and the limited landing zone required the use of a fenestrated/branched arch endograft. Physician-modified fenestrated stent-grafts are considered suitable for patients in an acute setting. The device became malrotated in a clockwise direction during deployment; therefore, cannulation of the first inner branch using a through-and-through wire technique was needed. The final angiogram showed a good result.

CONCLUSION

Thoracic endovascular repair of an aortic arch aneurysm using a through-and-through technique can be considered for high-risk patients in an acute setting.

Stabilizing Technique for Bridging Stent Placement in Branched Endovascular Aortic Repair

PURPOSE

To present a bailout technique for bridging covered stent placement during branched endovascular aortic repair (BEVAR) in complex anatomy.

TECHNIQUE

BEVAR is an alternative technique for the treatment of thoracoabdominal aortic aneurysms (TAAAs). Visceral and renal vessels must be preserved by bridging covered stent placement through downward-oriented branches of the main stent graft device. Challenging anatomy such as kinking and elongation of the aorta, or type III aortic arch configuration may impede successful catheterization of these branches due to reduced steerability and pushability of the endovascular material. Different alternative techniques have been described to overcome these anatomic barriers. This technical note adds another endovascular solution to complex cases using the guiding sheath stabilizing technique. It is based on a standard "through-and-through" technique. An attached snare is inserted via femoral approach, providing a stable position for branch catheterization and bridging covered stent deployment.

CONCLUSION

The stabilizing technique is safe and easy to perform and provides a stable position of the guiding sheath when antegrade branch catheterization is challenging. This technique is an additional tool for handling challenging cases.

A Branch-to-Branch Through-and-Through Wire Technique to Redirect a Branch Malposition in Multibranched Endovascular Aortic Aneurysm Repair

OBJECTIVE

To describe a novel technique to redirect a malrotated branch when treating a symptomatic juxtarenal aortic aneurysm using an off-the-shelf multibranched endograft.

TECHNIQUE

A 75-year-old patient was admitted because of a symptomatic juxtarenal aortic aneurysm with a maximum diameter of 9.2 cm. The aneurysm showed no infrarenal neck. Because of his comorbidities, an endovascular repair using off-the-shelf multibranched endograft was considered as urgent procedure. During the deployment, the devise malrotated clockwise. The incorporation of the renal branches was performed successfully; however, the superior mesenteric artery (SMA) branch was malpositioned, so that the SMA could not be cannulated. Both celiac and SMA branches were simultaneously cannulated and snared outside of the endograft redirecting the malrotated SMA branch (a branch-to-branch through-and-through wire technique). Leaving the through-and-through wire in situ, the SMA could be intubated using parallel wire through the SMA branch. The final angiogram showed a good perfusion of the renovisceral vessels. The aneurysm was completely excluded. The patient was discharged into a rehabilitation facility 8 days later without complications. The 12-month follow-up period was uneventful.

CONCLUSION

A branch-to-branch through-and-through wire technique for branch repositioning is feasible and may present a bailout tool.

Incorporation of Celiomesenteric Trunk With Double Kissing Directional Branches During Fenestrated-Branched Endovascular Aortic Repair

PURPOSE

Common celiomesenteric trunk (CMT) is a rare anatomical variation that occurs in 0.5% to 3.4% of the general population. Its presence may complicate planning and implantation of fenestrated and branched stent-grafts because the wide diameter and short length of the CMT to its bifurcation does not allow sufficient sealing for placement of bridging stents.

CASE REPORT

We report a patient with thoracoabdominal aortic aneurysm (TAAA) and CMT treated by fenestrated-branched endovascular aortic repair (FB-EVAR) using double kissing directional branches to incorporate the celiac axis and superior mesenteric artery. Pitfalls of stent design and implantation are outlined.

CONCLUSION

Double kissing directional branches should be considered as an alternative to incorporate vessels with early bifurcation such as a CMT.

Stent Graft Modification to Preserve Intercostal Arteries Using Thoracoabdominal Off-the-Shelf Multibranched (t-Branch) Endograft

Purpose: To demonstrate an off-the-shelf multibranched (t-Branch) modification to allow intercostal arteries preservation during juxtarenal, pararenal, paravisceral, and extent IV thoracoabdominal aortic aneurysm repair. Technique: The t-Branch is an off-the-shelf device not customized for specific patient anatomy and may be offered for urgent endovascular repair for patients with complex aortic aneurysms. However, a concern when treating patients who do not aneurysms extending above the celiac axis is that the more proximal extension which is required with this device may render patients at high risk for spinal cord injury. We report a novel technique with t-Branch modification performing a 180° fabric back windows at the first 2 sealing stents that allow perfusion to the intercostal arteries. Conclusion: T-Branch-PIA (preserving intercostal arteries) modification limits intercostal arteries coverage while optimizing proximal seal zone in juxtarenal, pararenal, paravisceral, and extent IV thoracoabdominal aneurysms, thereby may decrease the risk of spinal cord injury.

Increasing Role of Fenestrated and Branched Endoluminal Techniques in the Thoracoabdominal Segment Including Supra- and Pararenal AAA

Fenestrated and branched stent-grafts are being increasingly used to address complex pararenal and thoracoabdominal aortic aneurysms by endovascular means. The present paper describes the current indications, anatomical suitability and techniques of fenestrated and branched stent-grafts in the treatment for pararenal and thoracoabdominal aortic pathologies. Published outcomes with regard to perioperative mortality and morbidity, survival, reinterventions and target vessel patency during follow-up are also presented. Finally, advantages and disadvantages of endovascular repair as compared to open repair are discussed.

Balloon-Anchoring Technique to Stabilize Target Vessel Catheterization in Complex Endovascular Aortic Repair

Purpose: To describe a bailout technique to stabilize target vessel catheterization in branched endovascular aortic repair. Technique: The technique is demonstrated in a 75-year-old patient with a 75-mm symptomatic type III thoracoabdominal aortic aneurysm that was treated with a t-Branch endograft. If a catheter cannot be advanced for exchange to a more stable guidewire after target vessel catheterization, the balloon-anchoring technique can be applied to stabilize the through-the-branch hydrophilic guidewire. Through a femoral access a catheter and hydrophilic wire are passed outside the device into the target vessel and exchanged with a stiff wire; a semicompliant balloon is advanced over the Rosen wire and inflated in the target vessel, stabilizing the through-the-branch hydrophilic wire and facilitating its exchange with a stiff wire over a catheter or advancement of the bridging covered stent directly. Conclusion: The balloon-anchoring technique adds to the spectrum of bailout techniques that can be applied in cases of challenging target vessel access.

Parallel Graft Technique in a Complex Aortic Aneurysm: The Value of Intra-operative Flexibility from The Original Operative Plan

Introduction

The parallel grafting technique (PGT) is a valuable alternative to prefabricated branched or fenestrated endovascular aortic repair. An often overlooked advantage of PGT is its unique adaptability to different anatomical challenges that might appear intra-operatively.

Report

A 72 year old male patient presented with a 60 mm thoracic aneurysm, 59 mm juxtarenal abdominal aortic aneurysm, and 32 mm common iliac aneurysm (CIAA). Thoracic endovascular aortic repair plus endovascular aortic repair with bilateral renal artery chimneys and CIAA exclusion applying the sandwich technique was proposed. Because of unfavourable angulation it was not possible to achieve selective left renal catheterisation via axillary access. Changing to a femoral approach allowed successful retrograde catheterisation. The procedure ended with a chimney for the right renal artery and a periscope for the left renal artery. The final angiogram showed no endoleaks and renal and hypogastric patency. The patient was discharged three days after the procedure and remains under ultrasound surveillance after 40 months because of a small type two endoleak.

Conclusion

When using a prefabricated branched device, the possibility of selectively catheterising a visceral branch often has no straightforward solution. However, parallel grafting is an extremely flexible technique, which was of paramount importance for the surgical outcome of the present case.

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The parallel grafting technique (PGT) can be a valuable alternative to prefabricated branched or fenestrated endovascular aortic repair.

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An often overlooked advantage of PGT is its unique adaptability to different anatomical challenges that might appear intra-operatively.

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This is a complex case report with three year follow up, in which three consecutive aneurysms were treated with PGT.

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In this case the unique adaptability of the technique was paramount for the outcome of the surgery.

Emergent Use of a Branched Arch Device to Treat an Ascending Aortic Rupture: A Branch-to-Branch Through-and-Through Wire Technique to Compensate for Rotation Error

Purpose: To present a novel means of overcoming a rotation error when treating a ruptured ascending aorta with a branched arch endograft. Technique: The technique is demonstrated in an 83-year-old patient with cardiac and respiratory comorbidities and a contained rupture of the ascending aorta who was referred for endovascular therapy. Computed tomography angiography (CTA) showed progressive pseudoaneurysm and mediastinal hematoma, but the limited landing zone required the use of an inner branched arch endograft that was designed for another patient. The device became malrotated clockwise during deployment, so cannulation of the first inner branch was done using a branch-to-branch through-and-through wire from the second inner branch. The final angiogram showed a good result, with patency of the supra-aortic vessels and exclusion of the rupture. The patient was discharged 2 weeks later without complications. The 1-month CTA was free from endoleak. The patient returned to his normal activity 3 months later. Conclusion: The use of a branched arch stent-graft for emergent repair of a ruptured ascending aorta is feasible.

Advanced Technical Considerations for Implanting the t-Branch Off-the-Shelf Multibranched Stent-Graft to Treat Thoracoabdominal Aneurysms

Purpose: To demonstrate different techniques and device modifications that can expand the anatomic suitability of the off-the-shelf multibranched t-Branch for treatment of thoracoabdominal aortic aneurysm. Technique: The t-Branch device is not customized for specific patient anatomy, and the most frequent limitations to its use are an inadequate sealing zone and renal artery anatomy. Experience with this device has prompted the development of several techniques that can be employed to maximize the suitability of this stent-graft. Advice is offered on modification of the device to minimize the risk of paraplegia or better match patient anatomy. Maneuvers are explained to ease delivery through tortuous anatomy or existing stent-grafts, catheterize visceral target vessels, select a bridging stent, reduce ischemia time in the limbs, and alter the configuration of the branches. Conclusion: Employing adjunctive maneuvers can increase the anatomic suitability of the t-Branch; in our experience, these techniques have increased the applicability to more than 80% of all elective and urgent thoracoabdominal aortic aneurysm cases.

Technique for Fenestrated Stent-Graft Implantation as a Proximal Extension to a Previous Fenestrated Endovascular Repair for Abdominal Aortic Aneurysm

Purpose: To describe planning and a technique for fenestrated endovascular repair of a large Crawford type IV thoracoabdominal aortic aneurysm after previous 2-fenestration endovascular aneurysm repair (FEVAR). Technique: The first FEVAR procedure performed at another center implanted a standard Zenith device with 2 fenestrations and 1 scallop for a juxtarenal abdominal aortic aneurysm. The diameter of the Crawford type IV thoracoabdominal aortic aneurysm had progressed from 68 to 75 mm within a year after the FEVAR. Since the celiac trunk was already occluded, a 3-fenestration 22-×172-mm stent-graft was chosen to extend the existing stent-graft further proximally. A tapered 38/22-×179-mm Zenith custom-made device was designed for the thoracic component. The technique addresses several issues that arise during a FEVAR-in-FEVAR case, such as the orientation of the new stent-graft and its fenestrations, the absence of space between the 2 devices for maneuvers, and the difficulty in catheterizing target vessels with existing bridging stents, for which a bailout “snare-ride” maneuver is described. Conclusion: FEVAR after previous FEVAR is a feasible and efficient treatment option. The modified “snare-ride” technique can be used to catheterize target vessels in the absence of an Indy snare.