In Situ Antegrade Laser Fenestrations During Endovascular Aortic Repair

In situ laser fenestration of aortic septum to bridge false and true lumen during endovascular repair of aortic dissection

Fenestration of the septum between the true and false lumen might be necessary after aortic dissection. We report the technical aspects of in situ laser fenestration of the aortic dissection septum. Two illustrative cases are provided: a 56-year-old man with false lumen deployment of a frozen elephant trunk graft, and a 67-year-old man who underwent fenestrated endovascular aortic repair with a target branch vessel off the false lumen. In both cases, the septum was crossed using in situ laser fenestration. This technique is a precise option to enable passage between true and false lumens during endovascular repair of an aortic dissection.

Comparison of the Snare Loop Technique and the Hungaroring Reinforcement for Physician-Modified Endograft Fenestrations-An In Vitro Study

BACKGROUND

We conducted an in vitro comparison of the snare loop reinforcement against a closed-loop reinforcement (Hungaroring) for physician-modified endograft (PMEG) fenestrations regarding preparation time and stability during flaring balloon dilatation.

MATERIALS AND METHODS

The time to complete a PMEG fenestration with reinforcement was measured and compared between the Hungaroring and snare loop groups. The number of stitches was counted. Each fenestration was dilated using a 10 mm high-pressure, non-compliant balloon up to 21 atm in pressure, and fluoroscopic images were taken. The presence of indentation on the oversized balloon at the level of the reinforcement was evaluated at each fenestration.

RESULTS

Five fenestrations were created in each group (n = 5) for a total of ten pieces. The completion time in the snare loop group was 1070 s (IQR:1010-1090) compared to 760 s (IQR:685-784) in the Hungaroring group (p = 0.008). Faster completion time was achieved by faster stitching (23.2 s/stitch (IQR 22.8-27.3) for the snare loop group and 17.3 s/stitch (IQR 17.3-20.1) for the Hungaroring group (p = 0.016). None of the fluoroscopic images of the snare loop reinforcement showed an indentation on the balloon during the overexpansion; on the contrary, the Hungaroring showed indentation in every case, even at 21 atm.

CONCLUSION

Fenestrations reinforced with Hungaroring can be completed significantly faster. Furthermore, the Hungaroring resists over-dilation even at high pressures, while snare loop reinforcements dilate at nominal pressure.

Early and Midterm Outcomes of Endovascular Aortic Arch Repair Using In Situ Laser Fenestration

INTRODUCTION

The aim of this study is to present single-center outcomes in patients treated with in situ laser fenestration thoracic endovascular aortic repair (LFTEVAR) for various aortic arch pathologies and assess the impact of increasing experience.

METHODS

The STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) statement was followed. A retrospective analysis of prospectively collected single aortic center data was conducted, including baseline information and peri- and post-operative outcomes of consecutive patients managed with LFTEVAR for aortic arch pathologies. Patients were enrolled from April 1, 2017 to January 31, 2023. The cohort was dichotomized to compare early (2017-2019) and late experience (2020-2023). Primary outcomes were peri-operative mortality and cerebrovascular morbidity.

RESULTS

Thirty patients were included (63.3% males, mean age 69.8±9.6 years); 21.4% presented with aortic ruptures. Aortic aneurysm involving the aortic arch was the most frequent pathology (53.3%). Forty target vessels (TVs) were revascularized, including 19 left subclavian arteries (47.5%) and 17 left common carotid arteries (42.5%). Double fenestrations were performed in 10 patients. The proximal landing zone was Ishimaru zone 0 in 5 patients (16.7%) and zone 1 in 13 patients (43.3%). Technical success was 93%. No spinal cord ischemia was recorded, and 3 patients (10%) suffered a post-operative stroke, of which 1 was major (3.3%). The median follow-up was 12 months (range=1-48 months). Thirty-day and follow-up mortality rates were 13.5% and 15.3%, respectively. Target vessel instability was 10%, of which 3.8% required reintervention. There was no statistically significant difference in outcomes between the early and late experience groups.

CONCLUSIONS

Laser fenestration thoracic endovascular aortic repair of the aortic arch performed in experienced aortic centers is associated with low early mortality and stroke rates. It is a safe and effective therapeutic option in patients considered unfit for open repair.

CLINICAL IMPACT

Custom-made devices for arch pathologies requiring urgent repair are not an option because of manufacturing delays. Off-the-shelf devices with single branch arch prostheses, and outside IFU techniques such as parallel-grafts and surgeon-modified endografts have been proposed in this setting. Another off-the-shelf alternative is in situ laser fenestration thoracic endovascular repair (LFTEVAR), which addresses many limitations of the other off-the-shelf options. Our study reports the outcomes of 30 patients treated with LFTEVAR, showing that it is a viable therapeutic option in patients considered unfit for open repair acknowledging that sufficient experience with complex endovascular aortic repair is mandatory to achieve acceptable outcomes in these high-risk patients with challenging aortic anatomies.

In Situ Laser Fenestration Technique: Bench-Testing of Aortic Endograft to Guide Clinical Practice

PURPOSE

In situ laser fenestration (ISLF) is a recently introduced technology that offers the potential to perform total endovascular treatment of aortic arch and thoracoabdominal aortic pathologies in the acute setting. This experiment's aim was to assess ISLF in some currently common aortic endografts and bridging stent-grafts.

MATERIALS AND METHODS

Three different aortic endografts were evaluated: (1) Zenith Alpha, (2) Zenith TX2, and (3) Conformable GORE TAG. Each endograft was submerged in 37°C saline to create fenestrations using the 308 nm CVX-300 Excimer Laser System fitted with a 2.3 mm diameter Turbo-Elite laser atherectomy catheter compatible with a 0.018″ guidewire. Three different 8 mm bridging stent-grafts were evaluated: (1) BeGraft peripheral, (2) BeGraft peripheral plus, and (3) GORE VIABAHN VBX Balloon Expandable. All bridging stent-grafts were deployed and exposed to different balloon sizes and pressures. The ISLFs and bridging stent-grafts were then evaluated for any tears, stenoses, and seal.

RESULTS

A laser fenestration was consistently rapidly obtained in the Zenith Alpha and the Zenith TX2 endografts while it proved difficult to achieve a timely fenestration in the C-TAG. No fabric tears were noted in the Zenith Alpha and Zenith TX2 when inflating Armada (Abbott) 8 mm balloon in the fenestrations with pressures up to 15 atmospheres (rated burst pressure) nor when flaring bridging stent-grafts with balloons up to 12 mm in diameter at 10 atmospheres, while major tears were frequently noted in the C-TAG when the Armada 8 mm balloons were inflated. BeGraft Peripheral and BeGraft Peripheral Plus were all firmly attached to the fenestrations showing good seal on manual testing, while every sixth VBX bridging stent-graft displayed poorer attachment to the fenestration before dilatation at high pressure. Commonly, significant stenoses remained in the bridging stent-grafts after dilatation at nominal pressure, which could only be eradicated with high-pressure balloons.

CONCLUSION

In this limited bench-test, Dacron endografts responded well to the ISLF technology. Satisfactory deployment of the bridging stent was noted only after inflation and/or flaring with high-pressure balloons. Further work with different types of commercially-available bridging stent-grafts and endografts to assess the durability of in situ fenestration (ISF) and bridging stents in ISF is recommended.

CLINICAL IMPACT

This report on experimental in situ laser fenestration provide important insights for clinicians considering using in situ laser fenestration of aortic stentgrafts in vivo. In particular, different laser settings were tested together with a selection of aortic stentgrafts. Also, the target pressure needed in PTA balloons to dilate the fenestrations and any subsequent tears in the fabric were noted. This was followed by deployment of assorted balloon-expandable stentgrafts with estimation of residual stenosis and seal.

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Off-the-Shelf Single-Fenestrated Endograft for Emergent Juxtarenal and Pararenal Abdominal Aortic Aneurysm

INTRODUCTION

Endovascular solutions to emergent juxtarenal and pararenal abdominal aortic aneurysms (AAAs) are complicated. Endovascular aortic repair (EVAR) with in situ laser fenestration (ISLF) is promising but requires a period of visceral ischemia. With an off-the-shelf, single superior mesenteric artery (SMA)-fenestrated device mesenteric ischemia is avoided and renal ischemia decreased. The aim was to develop an optimized design of such an endograft suitable for >90% of juxtarenal and pararenal AAAs.

METHODS

Single-center analysis on 44 consecutive preoperative CTs for previously elective fenestrated EVARs for juxtarenal and pararenal aneurysms. Anatomical characteristics were analyzed to define: (1) shortest aortic coverage above SMA fenestration to achieve ≥4 cm seal; (2) feasibility of a scallop for the celiac artery; (3) shortest distance between the SMA and lowest renal, to facilitate renal ISLF in a straight endograft; (4) distance from the lowest renal to the aortic bifurcation, to allow an overlapping zone >40 mm with a bifurcated stent graft; (5) aortic diameter in the sealing zone, for optimal proximal stent graft diameter with 10% to 30% oversizing; (6) the final design was then tested on individual level.

RESULTS

(1) The stent graft needs to start 40 mm above the SMA fenestration to achieve a 4 cm sealing zone in >90% of cases. (2) A proximal sealing zone of 40 mm without a scallop covers 77% of celiac arteries. With an addition of a 20 mm deep, 20 mm wide scallop at 12:30, the stent graft still covers 27% of celiacs. This suggests that a scallop would not be practically feasible. (3) In >90% of cases, the lowest renal was <31 mm from the SMA, suggesting that the tapering should start 30 mm below the SMA. (4) The distance from the lowest renal to the aortic bifurcation ranged from 82 to 166 mm. This allows for a 20 mm tapering and 50 mm straight part in all cases. (5) The 5th and 95th percentile of the aortic diameter in the sealing zone was 22 and 31 mm, respectively. Thus, 2 different stent graft diameters (28 and 34 mm) would fit >90% of cases. (6) The final design was suitable in 91% cases.

CONCLUSIONS

Two sizes of a single-fenestrated aortic stent graft without scallop cover >90% of juxtarenal and pararenal anatomies.

CLINICAL IMPACT

Emergent juxta- and pararenal aortic aneurysms is a difficult clinical scenario that continuously challenges physicians. An endovascular option is in situ laser fenestrated endografts. One risk with these is the complete visceral ischemia occurring before the fenestrations are completed. An off-the-shelf single-fenestrated stent graft facilitates the treatment by removing the ischemia time for the SMA and reducing the ischemia time for the celiac and renal arteries thus decreasing the risk of visceral ischemia complications.

Integration of a Custom-Made Fenestration to Simplify Acute Reno-Visceral In Situ Aortic Repair

PURPOSE

To illustrate the technique of antegrade in situ laser fenestration (ISLF) on a predesign custom-manufactured stent-graft with single reinforced fenestration for use in emergency endovascular repair of complex abdominal aortic aneurysms (AAAs).

TECHNIQUE

A short custom-made device (CMD) fenestrated graft was predesigned with a single preloaded 8 mm strut-free fenestration at 12 o'clock position. A modified preloaded system was used to allow unilateral access from the distal port if necessary. After bilateral percutaneous femoral access, the graft was deployed under fusion guidance with the CMD fenestration matching the superior mesenteric artery (SMA) origin and immediately bridged as per standard technique. The aneurysm was then excluded with a bifurcated device. A large steerable sheath was used to allow for sequential antegrade laser in situ fenestration and stenting of the renal arteries.

CONCLUSIONS

Single-vessel customized short fenestrated grafts for the SMA and antegrade in situ laser renal fenestrations are technically feasible for repair of acute complex AAAs even after previous infrarenal reconstruction. It could become an off-the-shelf solution to limit aortic coverage and reno-visceral ischemia, even in patients with a narrow aortic diameter at the renal level.

CLINICAL IMPACT

Single-vessel precustomized short fenestrated grafts for the SMA combined with renal artery antegrade ISLF can be a feasible option for the acute repair of patients with complex aneurysms and a narrow aortic diameter at the reno-visceral segment. It may limit aortic coverage and reno-visceral ischemic time and also be applicable after previous infrarenal endovascular aneurysm repair (EVAR).

Anatomical feasibility of the current endovascular solutions for Juxtarenal aortic abdominal aneurysm repair

PURPOSE

Endovascular repair of juxta-renal aneurysms (JAAAs) can be achieved by fenestrated endografts (FEVAR), parallel-grafts (CHEVAR) and standard abdominal endografts + endoanchors (ESAR). Aim of this study was to evaluate the incidence of their anatomical feasibility in JAAAs.

MATERIALS AND METHODS

All patients submitted to JAAAs treatment from 2006 to 2019 were retrospectively analyzed, irrelevant of the procedure performed. Juxta-renal aneurysm was defined according with the current ESVS clinical practice guidelines. Preoperative computed tomography angiographies were analyzed to evaluate the anatomical feasibility of: FEVAR (Cook Zenith-platform; CE-marked or custom-made device), CHEVAR (Medtronic Endurant + Atrium Advanta - CE marked combination) and ESAR (Medtronic Endurant + Helifix - CE marked combination) according with the manufactures' instruction for use. The anatomical feasibility of these three endovascular solutions was assessed according with the proximal neck, target visceral vessels (TVVS) and iliac access characteristics.

RESULTS

Ninety-nine cases were considered. There were no cases of frank aortic rupture and in all patients at least one arterial access from above was available. Fenestrated endograft, CHEVAR, and ESAR were anatomically feasible in 93 (94%), 37 (37%), and 27 (27%) cases, respectively (p <. 001). Fenestrated endograft requires design with <3, three and >3 fenestrations in 29 (31%), 33 (36%), and 31 (33%) cases, respectively. Parallel graft technique have required 1 or 2 parallel graft configurations in 12 (12%) and 25 (25%) cases, respectively. Among the 14 cases with aneurysm diameter >70 mm, the anatomical feasibility of FEVAR, CHEVAR, and ESAR was 13(93%), 4(29%), and 4 (29%) cases, respectively (p < .001).

CONCLUSION

Fenestrated endograft is more frequently applicable than CHEVAR and ESAR as endovascular treatment of JAAAs. Since this difference is valid also in aneurysms with diameter >70 mm, the issue of a rapid availability is of paramount importance. The 6% of cases have not any endovascular solution and requires open surgery.

Urgent and emergent repair of complex aortic aneurysms using an off-the-shelf branched device

Introduction

Endovascular repair using off-the-shelf endografts is a viable solution in patients with ruptured or symptomatic complex aortic aneurysms. This analysis aimed to present the peri-operative and follow-up outcomes in urgent and emergent cases managed with the t-Branch multibranched thoracoabdominal endograft.

Methods

Prospectively collected data from all consecutive urgent and emergent cases managed in two aortic centers between January 1st, 2014, to November 30th, 2022, using the t-Branch device (Cook Medical Inc., Bjaeverskov, Denmark) were analyzed. Patients presenting with ruptured aortic complex aneurysms were characterized as emergent and patients with aneurysms >90 mm of diameter, or symptomatic aneurysms were characterized as urgent. Technical success, 30-day mortality, major adverse events (MAE) and spinal cord ischemia (SCI) rates were assessed.

Results

225 patients (36.5% females, 72.5 ± 2.8 years) were included; 73.0% were urgent. The mean aneurysm diameter was 109 ± 3.9 mm and 44.4% were type I-III TAAAs. Females (p = .03), para-renal aneurysms (p = .02) and ASA score IV (p < .001) were more common in emergent cases. Technical success was 97.8%. Thirty-day mortality and MAE rates were 17.8% and 30.6%, respectively. SCI rate was 14.7%, (4.8% paraplegia rate) with 22.2% of patients receiving prophylactic cerebrospinal drainage. Thirty-day mortality (13.3% vs. 26.7%, p = .04) and MAE (26.0% vs. 43.0%, p = .02) were more common among emergent cases while technical success (97.6% vs. 98.3%, p = .9), and SCI (13.3% vs. 18.3%, p = .4) were similar. Survival at 12-months was 83.5% (SE 5.9%) for the urgent and 77.1% (SE 8.2%) for the emergent group (log rank, p = 0.96).

Conclusion

T-Branch represents an effective and safe solution for the management of urgent and emergent cases with complex aortic aneurysms, with high technical success, promising early mortality and SCI rates.

Mechanical Comparison between Fenestrated Endograft and Physician-Made Fenestrations

INTRODUCTION

A fenestrated endograft (FE) is the first-line endovascular option for juxta and pararenal abdominal aortic aneurysms. A physician-modified stent-graft (PMSG) and laser in situ fenestration (LISF) have emerged to circumvent manufacturing delays, anatomic standards, and the procedure's cost raised by FE. The objective was to compare different fenestrations from a mechanical point of view.

METHODS

In total, five Zenith Cook fenestrations (Cook Medical, Bloomington, IN, USA) and five Anaconda fenestrations (Terumo Company, Inchinnan, Scotland, UK) were included in this study. Laser ISF and PMSG were created on a Cook TX2 polyethylene terephthalate (PET) cover material (Cook Medical, Bloomington, IN, USA). In total, five LISFs and fifty-five PMSG were created. All fenestrations included reached an 8 mm diameter. Radial extension tests were then performed to identify differences in the mechanical behavior between the fenestration designs. The branch pull-out force was measured to test the stability of assembling with a calibrated 8 mm branch. Fatigue tests were performed on the devices to assess the long-term outcomes of the endograft with an oversized 9 mm branch.

RESULTS

The results revealed that at over 2 mm of oversizing, the highest average radial strength was 33.4 ± 6.9 N for the Zenith Cook fenestration. The radial strength was higher with the custom-made fenestrations, including both Zenith Cook and Anaconda fenestrations (9.5 ± 4.7 N and 4.49 ± 0.28 N). The comparison between LISF and double loop PMSG highlighted a higher strength value compared with LISF (3.96 N ± 1.86 vs. 2.7 N ± 0.82; p= 0.018). The diameter of the fenestrations varied between 8 and 9 mm. As the pin caliber inserted in the fenestration was 9 mm, one could consider that all fenestrations underwent an "elastic recoil" after cycling. The largest elastic recoil was observed in the non-reinforced/OC fenestrations (40%). A 10% elastic recoil was observed with LISF.

CONCLUSION

In terms of mechanical behavior, the custom-made fenestration produced the highest results in terms of radial and branch pull-out strength. Both PMSG and LISF could be improved with the standardization of the fenestration creation protocol.

Stent-Graft Fabrics Incorporating a Specific Corona Ready to Fenestrate

In situ fenestration of endovascular stent-grafts has become a mainstream bailout technique to treat complex emergent aneurysms while maintaining native anatomical visceral and aortic arch blood supplies. Fabric tearing from creating the in situ fenestration using balloon angioplasty may extend beyond the intended diameter over time. Further tearing may result from the physiologic pulsatile motion at the branching site. A resultant endoleak at the fenestrated sites in stent-grafts could ultimately lead to re-pressurization of the aortic sac and, eventually, rupture. In an attempt to address this challenge, plain woven fabrics were designed. They hold a specific corona surrounding a square-shaped cluster with a plain weave fabric structure, a 2/2 twill, or a honeycomb. The corona was designed to stop potential further tearing of the fabric caused by the initial balloon angioplasty and stent or later post-implantation motion. The cluster within the corona was designed with relatively loose fabric structures (plain weave, 2/2 twill weave, and honeycomb) to facilitate the laser fenestration. Two commercial devices, Anaconda (Vascutek, Terumo Aortic) and Zenith TX2 (Cook), were selected as controls for comparison against this new design. All the specimens were characterized by morphology, thickness, and water permeability. The results demonstrated that all specimens with a low thickness and water permeability satisfied the requirements for a stent graft material that would be low profile and resistant to endoleaks. The in situ fenestrations were performed on all fabrics utilizing an Excimer laser followed by balloon angioplasty. The fabrics were further observed by light microscopy and scanning electron microscopy. The dimension of the fenestrated apertures was smaller than the balloon's diameter. The tearing was effectively confined within the corona. The clinical acceptability of this concept deserves additional bench testing and animal experimentation.

Emergent endovascular treatment options for thoracoabdominal aortic aneurysm

For a long time, parallel grafting, physician-modified endografts, and, more recently, in situ fenestration were the only go-to endovascular options for ruptured thoracoabdominal aortic aneurysm, offered mixed results, and depended mainly on the operator's and center's experience. As custom-made devices have become an established endovascular treatment option for elective thoracoabdominal aortic aneurysm, they are not a viable option in the emergency setting, as endograft production can take up to 4 months. The development of off-the-shelf (OTS) multibranched devices with a standardized configuration has allowed the treatment of ruptured thoracoabdominal aortic aneurysm with emergent branched endovascular procedures. The Zenith t-Branch device (Cook Medical) was the first readily available graft outside the United States to receive the CE mark (in 2012) and is currently the most studied device for those indications. A new device, the E-nside thoracoabdominal branch endoprosthesis OTS multibranched endograft (Artivion), has been made commercially available, and the GORE EXCLUDER thoracoabdominal branch endoprosthesis OTS multibranched endograft (W. L. Gore and Associates) is expected to be released in 2023. Due to the lack of guidelines on ruptured thoracoabdominal aortic aneurysm, this review summarizes the available treatment options (ie, parallel grafts, physician-modified endografts, in situ fenestrations, and OTS multibranched devices), compares the indications and contraindications, and points out the evidence gaps that should be filled in the next decade.

Midterm Outcomes of Antegrade In Situ Laser Fenestration of Polyester Endografts for Urgent Treatment of Aortic Pathologies Involving the Visceral and Renal Arteries

OBJECTIVE

Aortic endografting and antegrade in situ laser fenestration of visceral arteries (LFEVAR) may be considered as an alternative to open surgery for the emergency repair of complex abdominal aortic aneurysms (AAA) in fragile patients. The aim of this article was to evaluate the midterm results of LFEVAR performed with polyester endografts.

METHODS

From August 2015 to December 2020, all consecutive LFEVAR performed for non-deferrable treatment of complex AAA were analysed. Polyester endografts were deployed and subsequently fenestrated using an atherectomy laser probe; the fenestrations were enlarged using cutting and semicompliant balloons before implantation of balloon expandable bridging stents into the target vessels. Prospectively collected midterm survival, patency, and re-intervention rates were analysed.

RESULTS

Forty four procedures were performed for 11 type 1a endoleaks, five thoraco-abdominal aneurysms, 20 pararenal aneurysms, four segmental renal artery (RA) preservations, three anastomotic aneurysms, and one aortic dissection. One hundred and eight laser fenestrations were performed (26 for the superior mesenteric artery [SMA], 13 for the coeliac trunk, 33 and 31 for the right and left RA, respectively). The median ischaemia duration was 7, 48, 48, and 45 minutes, respectively. The technical success rate was 97%, with no open surgical conversions. The 30 day mortality was 4.5% (n = 2). No spinal cord ischaemia events were observed nor early stent related complications. Kaplan-Meier overall survival at two years was 73%, the aortic related re-intervention free survival was 70%, and the stent related re-intervention free survival was 90.6%. Four target vessel thromboses were detected, of which three were rescued. Three type IIIc endoleaks, one RA false aneurysm, and one SMA stenosis, required re-intervention during a median follow up of 24.7 months.

CONCLUSION

Antegrade LFEVAR is feasible, safe, and provides satisfactory early and midterm outcomes for non-deferrable treatment of aortic pathologies involving the visceral segment. Long term data are mandatory to confirm the usefulness of this promising off label technique.

A Systematic Review of Contemporary Outcomes from Aortic Arch In Situ Laser Fenestration During Thoracic Endovascular Aortic Repair

BACKGROUND

In situ laser fenestrated endovascular aortic repair (L-FEVAR) is a novel and creative solution for complex aortic pathologies in the urgent and emergency setting. Outcomes of this technique, however, are poorly reported. We sought to evaluate the efficacy, safety, and outcomes of L-FEVAR in aortic arch pathologies.

METHODS

A systematic literature review and analysis were conducted in accordance with the preferred reporting items for systematic reviews and meta-analyses and Cochrane guidelines. A search was conducted using Google, PubMed, and Scopus to identify studies evaluating L-FEVAR. Two independent reviewers determined study inclusion. Case reports and series including < 10 patients were excluded. Reviewers also assessed the methodological quality and extracted data regarding outcomes. A meta-analysis of endoleak event rates was conducted using a fixed-effect model due to small sample size.

RESULTS

Eight studies met inclusion criteria between 2013 and 2021. Most studies were retrospective (87.5%) with median follow-up duration of 12.5 months (range 10-42). There were 440 patients included (range 15-148), mostly men (64%). Mean age was 61 years (range 53-68). Included patients were all symptomatic with L-FEVAR being technically successful in 93.3% of cases. The main indication for aortic arch intervention was aortic dissection. Single fenestrations occurred most frequently (68%), followed by triple (22%) then double fenestrations (9%). Meta-analysis of 8 studies (n = 440) demonstrated an endoleak event rate of 0.06 (95% confidence interval 0.04-0.09, P < 0.001) with no observed statistically significant heterogeneity of effects (Q = 7.91, P = 0.34). The median operative time was 162 min (range 53-252) with median length of stay of 10 days (range 7-17). Primary branch patency was 96.6%. Secondary patency rate was 97%. Pooled complication rates such as endoleak occurred in 4.8%, stroke in 2.0%, spinal cord ischemia in 0.2%, retrograde dissection in 0.9%, and 30-day death in 2.0%. Access complications occurred in 0.4%. Antiplatelet regimen was poorly reported in the study cohort.

CONCLUSIONS

In situ laser fenestration is a feasible, safe, and effective approach to treat aortic arch disease in patients who are unsuitable for open or custom-made endovascular means. High technical success and excellent short-term branch patency can be achieved. These single-institution series exhibit promising short-term outcomes. In a similar paradigm to investigational device exemptions studies for custom-made and physician modified endografts, these preliminary data make a persuasive argument for larger long-term multi-institutional prospective study of this promising technique.

Mechanical Performance Assessment of Physician Modified Aortic Stent Graft

OBJECTIVE

This study aimed to compare various fenestration configurations of physician modified aortic stent grafts in order to identify which design parameters have a significant influence on the mechanical behaviour of the fenestration.

METHODS

the fenestration configurations were considered according to different manufacturing parameters: cutting technique, fenestration reinforcement, suture material, reinforcement loop design, and number of suture points. The performance of the graft/bridging stent assembly was assessed at various levels: (1) branch pull out force; (2) fenestration enlargement and rupture strength; (3) balloon angioplasty resistance; and (4) behaviour under cyclic fatigue.

RESULTS

Sixty manual fenestrations were created. The tests performed on the fenestrations had several main findings. First, reinforcement increased the radial force on the branch, which increased the pull out force; this may limit migration of the bridging stent in vivo. The phenomenon was amplified with a snare reinforced fenestration, which seemed to be the most efficient. Moreover, increasing the number of suture passes also appeared to increase the branch extraction force securing the assembly. The enlargement tests showed that non-reinforced fenestrations had the weakest radial strength. This was confirmed with the balloon angioplasty test, which showed that these latter specimens undergo the most significant textile degradation. After fatigue tests, all fenestrations were larger, showing that elastic recoil was incomplete in all samples. The largest recoil was observed in the non-reinforced ophthalmological cautery (OC) fenestrations (40%). Regarding the behaviour of the samples up to rupture, all samples behaved in a similar way; however, the double loop fenestration strength level was the highest.

CONCLUSION

This study demonstrated that the snare double loop reinforcement has an advantage regarding durability of the graft branch assembly. Moreover, non-reinforced fenestrations show signs of weakness and lack of stability, which questions the in situ or laser fenestration procedures.

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.

In Situ Laser Fenestrations of Aortic Endografts for Emergent Aortic Disease

BACKGROUND

In situ laser fenestration (ISLF) is a novel endovascular technique which allows customization of a standard stent graft to a patient's anatomy. While most reported cases involve revascularization of the left subclavian artery (LSA), some centers have now reported their initial experience treating branches of the visceral aorta for aortic aneurysms. The aim of this study is to examine the adoption of ISLF in emergent aortic pathology at a specialized aortic center.

METHODS

Between December 2020 and February 2022, all patients who underwent ISLF as part of endovascular intervention for complex aortic pathology at a university hospital were identified. Cases were collected from a prospective aortic database with additional information obtained from a retrospective review of electronic hospital records.

RESULTS

Fifteen patients (11 men and 4 women) underwent emergency ISLF, with a median age of 76 years. Eleven presented with symptomatic or ruptured aortic aneurysms, three with acute complicated aortic dissections and 1 aortic traumatic transection. Most aortic aneurysms were thoraco-abdominal (n = 7), with 1 arch, 1 thoracic, 1 supra-renal, and one-juxta-renal aortic aneurysm. ISLF was performed to revascularize the LSA in 8 cases, and branches of the reno-visceral aorta in 7 cases. All LSA ISLF cases had left brachial artery exposure. Femoral access was percutaneous in 14 of 15 cases. Technical success was 96.3% (26/27)). Median ischemic times were: superior mesenteric artery 7 min, renal arteries 22 min, and celiac trunk 43.5 min. There were 2 early aortic/fenestration related reinterventions. There was no stroke and 1 death caused by heparin-induced thrombocytopenia within 30 days. The majority of patients did not require intensive care admission (n = 8). The median intensive care unit stay was 0 days and hospital length of stay 18 days. There was no fenestration endoleak or reintervention post discharge with a median follow-up of 168 days.

CONCLUSIONS

ISLF is a promising new technique that can show excellent technical results in experienced aortic centers, even during the learning curve. While custom-made devices with reinforced fenestrations are preferred in nonemergent situations, ISLF is a feasible option for complex aortic pathology in the acute setting when open surgery is not feasible.

Techniques of antegrade in situ laser fenestration for endovascular aortic repair of complex abdominal and thoracoabdominal aortic aneurysms

Antegrade in situ laser fenestration allows for incorporation of visceral and renal arteries during endovascular repair of complex abdominal and thoracoabdominal aortic aneurysms. This technique can be particularly useful for urgent and emergent cases and for centers without access to manufactured fenestrated-branched endovascular aneurysm repair devices. In the present report, we have described two techniques of antegrade in situ fenestration, the common pitfalls, and the anatomic considerations for each technique.

Type 1A Endoleak after TEVAR in the Aortic Arch: A Review of the Literature

Aortic arch repair is a challenging intervention. Open surgical repair is still considered the gold standard, but in high-risk patients, it is not always a reasonable option, making endovascular approaches an enticing, when not the only available, alternative for treatment. The strategies more commonly adopted are surgical supra-aortic trunk (SAT) rerouting followed by deployment of a standard thoracic endoprosthesis, chimney techniques, custom-made scalloped, fenestrated, and branched devices, and in situ or physician-modified fenestrations. If we excluded techniques involving SAT rerouting where the arch anatomy is surgically modified in order to make deployment in the aortic arch of a standard thoracic endoprosthesis possible, in the other techniques, one or more SATs are incorporated in the thoracic endoprosthesis. In these cases, no matter what solution is adopted, because of the morphology of the aorta at this level, achieving an ideal sealing is extremely difficult, and endovascular treatments of the arch are burdened by an increased risk of type IA endoleaks. PubMed, EMBASE, and Cochrane Library were searched. We identified 1277 records. After reading titles, abstracts, and full texts, we excluded 1231 records. Exclusion criteria were low-quality evidence, abstracts, case reports, conference presentations, reviews, editorials, and expert opinions. A total of 48 studies were included, for a total of 3114 patients. A type IA endoleak occurred in 248 patients (7.7%) with a mean incidence of 18.8% in chimney procedures, 4.8% and 3%, respectively, in fenestrated and branched devices, and 2.2% in in situ fenestration. We excluded from our analysis scalloped technology that is used when the target vessel originates from a healthy landing zone and represents a different anatomical setting. Type IA endoleaks are a concern with all types of endovascular aortic arch repair, and they can compromise the outcomes of the procedure. The rate of type IA endoleaks appears to be significantly higher in chimney procedures. In order to maximize sealing, whenever possible, endovascular repair of the arch should be achieved with custom-made fenestrated devices. However, chimney configurations are still a valuable solution particularly in the emergency setting, although in such a procedure, to guarantee accurate postoperative management and follow-up, an imaging protocol could be useful.

Clinical Validation of the Impact of Branch Stent Extension on Hemodynamics in ISF-TEVAR Involving LSA Reconstruction

Background

The study of hemodynamics regarding thoracic endovascular aortic repair (TEVAR) is helpful to improve the surgical efficacy.

Objective

Correlations between hemodynamic changes and branch stent extension length and interference factors for branch stent extension length of in situ fenestration TEVAR (ISF-TEVAR) involving the left subclavian artery (LSA) were evaluated.

Materials and Methods

This study retrospectively analyzed 196 patients with Stanford type B aortic dissection who received in situ laser fenestrated thoracic endovascular aortic repair with LSA fenestration from April 2014 to March 2021. Branch stent extension to the main stent graft was evaluated by the computed tomographic angiography (CTA). Hemodynamic change of LSA was defined as a 20 mmHg interbrachial systolic pressure difference. The factors affecting the extension of the branch stent were also evaluated.

Results

All patients underwent ISF-TEVAR with LSA fenestration, and there was no recurrence during the follow-up. The mean length of the branch stent extension was 10.37 ± 0.34 mm, which was used to divide the patients into long and short groups. Asymptomatic hemodynamic changes (defined as a 20 mmHg interbrachial systolic pressure difference) in LSA were observed in 61 patients undergoing ISF-TEVAR involving LSA fenestration. The Spearman correlation analysis showed extension length of a branch stent &gt;1.5 cm elevated the risk of hemodynamic changes.

Conclusion

Overall, we conclude that branch stent extension length &gt;1.5 cm induced LSA hemodynamic changes. Appropriate shortening of the stent extension length can improve the curative effect of ISF-TEVAR, especially when faced with a type II/III aortic arch and stent angles of &lt;30 degrees.

Comparative Early Results of In-Situ Fenestrated Endovascular Aortic Repair and Other Emergent Complex Endovascular Aortic Repair Techniques for Ruptured Suprarenal and Thoracoabdominal Aortic Aneurysms at a Regional Aortic Center

INTRODUCTION

Emergent endovascular repair of suprarenal (SRAAA) and thoracoabdominal aortic aneurysms (TAAA) poses a significant challenge due to the need for branch vessel incorporation, time constraints, and lack of dedicated devices. Techniques to incorporate branch vessels have included parallel grafting (PG), physician modified endografts (PMEG), double-barrel/reversed iliac branch device (DB/rIBE), and in situ fenestration (ISF). This study describes a single-center experience and the associated outcomes when using these techniques for ruptured SRAAA and TAAA.

METHODS

A retrospective review of patients who underwent endovascular repair of ruptured SRAAA and TAAAs from July 2014 - March 2021 with branch vessel incorporation was performed. Clinical presentation, intraoperative details, and postoperative outcomes of those who underwent ISF were compared to those who underwent repair using non-ISF techniques. The primary outcome of interest was in-hospital mortality. Secondary outcomes were major adverse events including myocardial infarction, respiratory failure, renal dysfunction, new onset dialysis, bowel ischemia, stroke, and spinal cord ischemia.

RESULTS

Forty-two patients underwent endovascular repair for ruptured SRAAA and TAAA, 18 of whom underwent ISF repair. Seventy-two percent of ISF patients were hypotensive prior to surgery, compared to 46% of the patients who underwent repair using non-ISF techniques (PMEG, PG, or DB/rIBE). The total procedural and fluoroscopy times were similar between the two groups despite a greater mean number of branch vessels incorporated with the ISF technique (3.1 vs. 2.2 per patient, P = .015). In-hospital mortality was 19% for all ruptures, and 25% for ruptures with hypotension. Compared to the non-ISF group, in-hospital mortality trended lower in the ISF group (11% vs. 25%, P = .233), reaching statistical significance when comparing patients who presented with hypotension (8% vs 45%, P =.048). The rate of major adverse events was 57% across all techniques and did not significantly differ between the ISF and non-ISF groups, with postoperative renal dysfunction being the most frequent complication (48%). Overall, ISF became the most commonly utilized technqiue later in the study period.

CONCLUSIONS

While emergent endovascular repair of ruptured SRAAA/TAAA remains a challenge, a number of techniques are available for expeditious treatment. In this series, ISF was associated improve survival, including a 5-fold reduction in mortality in patients presenting with hypotension, and has now become the dominant technique at our center. Despite these advantages, postoperative complications and reinterventions are common. Further experience and longer-term follow-up is needed to validate these initial results and assess durability.

Outcomes Following Urgent Fenestrated-Branched Endovascular Repair For Pararenal And Thoracoabdominal Aortic Aneurysms

OBJECTIVES

To evaluate outcomes following urgent or emergent fenestrated-branched endovascular aortic repair (F-BEVAR) for pararenal (PRA) and thoracoabdominal aortic aneurysms (TAAA) in patients considered high-risk for open repair.

METHODS

A retrospective, single institution evaluation of outcomes following F-BEVAR of symptomatic, rapidly enlarging, or ruptured PRA or TAAA treated with physician modified endograft (PMEG) and company manufactured devices (CMD). Outcomes were technical success, 30-day morbidity and mortality, and one year aortic related outcomes.

RESULTS

Thirty-two patients (23 male, mean age 74±9 years) underwent F-BEVAR using PMEG or CMD over a 12-year period. Fourteen patients underwent emergent repair for contained rupture and eighteen patients underwent urgent repair for symptomatic, mycotic or rapidly growing aneurysms. Aneurysm classification was PRA in 10 patients and TAAA in 22 (9 extent IV and 13 extent I-III). Twenty-three patients (72%) were repaired with PMEG and eight patients (26%) with CMD. Technical success was 97% with a total of 98 renal-mesenteric arteries incorporated using 67 fenestrations (68%), 29 directional branches (29%) and two double-wide scallops (2%). 30-day mortality was 6%, with one patient expiring from unclear causes after hospital discharge and the other from mesenteric ischemia. MAEs otherwise occurred in sixteen patients (50%) including minor stroke in three patients, transient paraparesis and heart failure in one patient each, and early return to the operating room in six patients. Mean follow up was 24±22 months. At 1- year, overall survival, freedom from aortic-related mortality and freedom from secondary intervention were 70%±8%, 94%±3 and 83%±7, respectively.

CONCLUSIONS

Urgent F-BEVAR of selected patients with PRA and TAAA is a feasible and potentially safe treatment in patients with suitable anatomy, with low rates of early mortality and spinal cord complications. Long-term follow up is needed to assess durability of repair and device-related complications.

Antegrade in situ laser fenestration of aortic stent graft during endovascular aortic repair: A case report

BACKGROUND

The endovascular repair of juxtarenal abdominal aortic aneurysms (JAAA) usually requires combination treatment with various stent graft modifications to preserve side branch patency. As a feasible technique, according to the situation, antegrade in situ laser fenestration still needs to be improved.

CASE SUMMARY

This report describes a case that was successfully treated with endovascular repair facilitated by antegrade in situ laser fenestration while maintaining renal arterial flow. Laser fenestration was performed using a steerable sheath positioned in the stent graft lumen in front of the renal artery ostium. With the bare stent region unreleased, renal artery perfusion could be maintained and accurate positioning could be achieved by angiography in real time.

CONCLUSION

This study suggests the feasibility and short-term safety of this novel antegrade in situ laser fenestration technique for select JAAA patients.

Endovascular treatment of thoracoabdominal aortic aneurysms

Endovascular repair of thoracoabdominal aneurysms using fenestrated and/or branched stent grafts is technically feasible and efficacious but carries a steep learning curve. This innovative surgical approach is associated with less perioperative morbidity than traditional open repair and its early and mid-term outcomes are very favorable. Spinal cord ischemia remains a devastating complication after these procedures, hence the importance of various neuroprotective strategies. Widespread applicability remains limited in the United States, as no custom-made or off-the-shelf endografts are commercially available. Access to these devices remains limited to physician-sponsored or industry-sponsored clinical trials, but results from the Cook p-Branch and Gore Thoracoabdominal Branch Endoprosthesis trials are on the horizon.

Isolated Ruptured Paravisceral Penetrating Aortic Ulcers

BACKGROUND

The goal of this study is to investigate the clinical presentation, treatment options, and outcomes of the patients with isolated ruptured paravisceral penetrating aortic ulcers (PV-PAU).

METHODS

All patients presenting with acute aortic syndrome from 2015 to 2020 were screened, of which patients with isolated ruptured PV-PAU were included in this retrospective study. Study endpoints were the assessment of treatment options, technical success, and clinical outcome. Outcome measures included major perioperative complications and mortality.

RESULTS

Sixteen patients (11 men; median age 68; IQR 60 - 75 years) presented with isolated ruptured PV-PAU were included in this study. The median follow-up was 25 months (range 1 - 51). Ruptured PV-PAUs represented 12.3% of the ruptured aortic aneurysms in all locations. PV-PAUs were found in segment A (n = 8, 50%), segment B (n = 5, 31%), and segment C (n = 3, 19%). PV-PAUs showed a mean protrusion distance of 27±10 mm, a mean neck diameter of 21 ± 7 mm, and maximal aortic diameter of 50 ± 11 mm. Five patients (31%) showed hemodynamic instability on admission and needed intense fluid resuscitation. Of those, 2 patients needed urgent laparotomy with a fast transabdominal supraceliac aortic clamping, one needed an aortic balloon occlusion to obtain rapid aortic control. The open aortic repair was the most frequently performed surgery (11/16, 69%), followed by hybrid procedures (3/16) and parallel graft chimney technique (2/16). Two patients died during the follow-up, calculating for in-hospital and 1-year mortality rates of 6 - 12%, respectively. The postoperative morbidity rate was 31%. Postoperative complications included acute renal failure (31%), pneumonia (25%), and 1case of ischemic colitis (6%). No spinal cord ischemia was reported.

CONCLUSIONS

Ruptured PV-PAU is a rare and challenging diagnostic and therapeutic entity. Open aortic repair seems to be a reliable option in treating patients with isolated ruptured PV-PAUs. Hybrid procedures and parallel stent-graft techniques can only be used in selected patients.

Early Clinical Outcomes of Retrograde In-Situ Branched Stent Grafting for Complex Aortic Arch Aneurysms

OBJECTIVE

To evaluate the early outcomes of retrograde in-situ branched stent grafting (RIBS) using the gutter balloon technique for complex aortic arch aneurysms (CAAs).

METHODS

The RIBS technique is an in-situ needle fenestration procedure during thoracic endovascular aortic repair (TEVAR) with the reconstruction of cervical branches. The Double-RIBS (D-RIBS) for the reconstruction of the left common carotid artery and the brachiocephalic artery using the gutter balloon technique was performed in 30 high-risk patients. We describe the early clinical results of the D-RIBS technique for CAAs. Primary endpoints were technical success and 30-day mortality. Secondary endpoints were postoperative complications, rates of endoleaks, overall survival, aneurysm-related death, and re-interventions.

RESULTS

The mean age was 77.1±6.6 years and the mean maximum minor-axis aneurysmal diameter was 65.9±8.9 mm. Twenty six patients underwent D-RIBS for elective arch aortic aneurysm and four patients were for reintervention after Zone 2 TEVAR failure. Stent graft puncture was performed 60 times from the common carotid arteries and technical success was achieved in all cases (100%). Postoperative complications included cerebral infarction in 2 patients (6.7%), recurrent nerve palsy in one patient (3.3%). The 30-day mortality was 0%. During the median follow-up period of 14 months (6-56), overall survival at 12 months was 92.3% without any aneurysm-related death. Type 1b and type 2 endoleaks were observed in one each and no reintervention was encountered.

CONCLUSION

Early clinical outcomes of the D-RIBS for high-risk patients with CAAs are acceptable. The gutter balloon method enables safe and reliable fenestration. Further studies and dedicated devices are warranted.

A systematic review of experimental and clinical studies reporting on in situ laser fenestration of aortic endografts

OBJECTIVE

To summarize available in-situ laser fenestration (ISLF) literature, including experimental studies with their subsequent recommendations regarding optimal fenestration technique and fabric; as well as the short and mid-term results of clinical studies.

METHODS

A systematic review of English articles was performed in MEDLINE, the Cochrane Database and EMBASE, following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines by two researchers. The search period was without starting date until the 31^st August 2020, and search terms included were in situ, laser, fenestration, and endograft. Quality assessment of the studies was performed using the Newcastle-Ottawa scale by two other independent researchers.

RESULTS

A total of 19 clinical studies were included, with a total of 428 patients (390 supra-aortic trunk ISLF, 38 visceral vessel ISLF). The technical success was 96.9% and 95.6% supra-aortic and visceral vessel ISLF, respectively. Most studies have less than 12-month follow-up, and the longest available follow-up (in one study) was 5-years for left-subclavian fenestration and 17-months for visceral vessel ISLF. Overall, the quality of the evaluated clinical studies was low. Six experimental studies were included, with the highest level of evidence suggesting fenestration of multifilament polyethylene terephthalate grafts, followed by dilation with either a 6- or 8-mm non-compliant balloon.

CONCLUSION

Experimental studies favour the use of multifilament polyethylene terephthalate , followed by dilation with non-compliant balloons as the most durable "in-vitro" technique for ISLF. Short-term outcomes for arch and visceral vessel revascularization are promising, with low rates of in-hospital mortality, stroke, and end-organ ischemia. Nonetheless, the long-term durability of ISLF is yet to be determined and they should be limited to selected symptomatic or urgent cases.

Caudally directed in situ fenestrated endografting for emergent thoracoabdominal aortic aneurysm repair

We previously described a transfemoral antegrade in situ laser fenestration technique (in situ fenestrated endovascular abdominal aortic aneurysm repair) for ruptured thoracoabdominal aortic aneurysms. In the present report, we have described an alternative technique of caudally directed in situ fenestrated endografts using upper extremity access for branch vessel incorporation. This technique involves partial deployment of the aortic stent graft in the thoracic aorta to achieve proximal control, followed by sequential branch incorporation using a laser probe through a steerable sheath, from the upper extremity access. The advantages of the technique include rapid proximal aortic control before branch incorporation without target vessel prestenting and separation of in situ fenestration from the target branch vessel origin, facilitating cannulation of angulated branch vessels.

Experimental Analysis of In Situ Fenestration of Endovascular Stent-Grafts: Comparison between Needle and Laser Puncture

BACKGROUND

To evaluate the quality of in vitro fenestrations during in situ fenestration (ISF) and investigate the differences between needle and laser puncture in current stent-grafts.

METHODS

An in vitro study evaluated the damage created by needle ISF on stent-graft fabrics versus laser ISF. Fenestrations were made in 5 different commercially available stent-grafts, including polyester stent-grafts (Relay, Valiant and Hercules) and expanded polytetrafluoroethylene (ePTFE) stent-grafts (TAG and Ankura). Each stent-graft received fenestration by needle and laser separately, followed by gradual dilation (4 mm, 6 mm, 8 mm, and 10 mm sequentially) of noncompliant balloons. Quantitative and qualitative evaluations including fenestration diameter, area, shape and margins were conducted using light microscopy and scanning electron microscope.

RESULTS

The primary fenestrations created by needle were slit-like with visible cut-off fibers in polyester stent-grafts and were almost circular with clear margins in ePTFE stent-grafts; those created by laser were squared or elliptical with ragged edges and burned fibers in all the stent-grafts. Fabric debris and toxic particles due to burning of the material were generated during laser-assisted fenestration. The Primary holes in polyester stent-grafts (Relay, Valiant and Hercules) by needle showed smaller area (0.05 mm² vs. 0.22 mm2, 0.52 mm² vs. 0.70 mm² and 0.28 mm² vs. 0.46 mm²; P < 0.01) and worse shape (0.93 vs. 2.46, 1.17 vs. 2.33 and 0.93 vs. 2.47; P < 0.01) than those by laser, while larger area (0.67 vs.0.43, 0.59 vs.0.45; P < 0.05), better shape (3.93 vs. 2.53, 3.90 vs. 2.93; P < 0.05) and better margin (3.83 vs. 2.47, 3.83 vs. 2.53; P < 0.05) in ePTFE stent-grafts (TAG and Ankrura). After gradual balloon dilation, the final holes showed no evident difference in maximal length, fenestration area, scores of shape and margin between the 2 ways of fenestration (P > 0.05). Ankura stent-graft showed the largest holes with best quality than the others.

CONCLUSIONS

The primary fenestrations were different between needle and laser puncture, laser induced fabric debris and toxic particles release should be cautiously considered. The final fenestrations were similar after gradual balloon dilation.

Initial Results of Antegrade Laser Fenestrations Using Image Fusion Guidance and Company Manufactured Stent Grafts in Complex Aortic Aneurysm Repair

OBJECTIVE

The aim was to describe initial outcomes of physician modified stent grafts using antegrade laser fenestrations and image fusion guidance (LEVAR) and company manufactured custom made (CM) stent grafts for the treatment of complex abdominal aortic aneurysms (CAAAs), thoraco-abdominal aortic aneurysms (TAAAs) and type I endoleaks (T1ELs).

METHODS

This was a retrospective single centre study. All LEVAR and Zenith (Cook) CM stent graft procedures between 1 January 2012 and 31 December 2018 were reviewed. Endpoints included intra-operative adverse events (IOAEs), in hospital mortality, re-interventions, target vessel patency, and 12 month outcomes (overall survival, freedom from re-intervention, target vessel patency). Outcomes at 12 months were estimated using the Kaplan-Meier method.

RESULTS

A hundred patients were identified and included in the study. All patients were deemed unfit for open repair. The cohort included 22 LEVAR and 78 CM stent grafts. LEVAR cases included painful aneurysms (n = 5), > 65 mm aneurysms (n = 10), anatomical constrains and/or presence of previous renal stents (n = 7) or cases declined by the manufacturer planning centre (n = 2). IOAEs were recorded in 41% of cases (n = 9) in the LEVAR group vs. 10% (n = 8, p = .002) in the CM group. The in hospital mortality rate in the LEVAR group was 9% (n = 2) vs. 4% (n = 3, p = .30) in the CM group. The median follow up duration was 22 months (7 - 38) in the LEVAR group and 28 months (11 - 78) in the CM group. The estimate of overall survival at one year was 91% in both groups. The freedom from re-intervention rate at one year was 58% in the LEVAR group vs. 87% in the CM group. The target vessel patency rates at one year were 95% in both groups.

CONCLUSION

In high risk patients deemed unfit for open repair, LEVAR may provide satisfactory 12 month overall survival and target vessel patency rates, though reported IOAE, mortality, and re-interventions rates were high thus requiring close and extensive follow up.

Comprehensive Review of Physician Modified Aortic Stent Grafts: Technical and Clinical Outcomes

OBJECTIVE

Physician modified stent grafts (PMSGs) present satisfactory results in selected cases of complex aortic pathologies. However, the technique lacks standardisation and depends on the surgeon and aortic segment. The aim of this article is to review comprehensively the technical details and clinical results of PMSGs related to patients with pathology in all aortic locations.

METHODS

A MEDLINE search (last search 20 April 2020) identified 20 relevant papers in the English language published over the last 20 years evaluating clinical outcomes after a PMSG and specifying the technical details to design it.

RESULTS

Seven hundred and eleven patients were included in the analyses, with 59% being operated on as an emergency. Ninety-two per cent of abdominal aortic segment PMSGs (A-PMSGs) were performed either as an emergency or before 2012. The main indications were available in 670 cases; 435 were degenerative aneurysms (64.9%) and 171 were aortic dissections (25.5%). Most of the endografts used were composed of polyethylene terephthalate, except for the Ankura (expanded polytetrafluoroethylene [Lifetech Scientific, Shenzhen, China]; n = 50, 7.5%). The Valiant (Medtronic, Minneapolis, MN, USA) represented 65% (n = 169) of aortic arch PMSGs (aa-PMSGs) and the Zenith platform (Cook Medical, Bloomington, IN, USA) 51% (n = 139) of A-PMSGs. A snare was used to reinforce the fenestration in 458 PMSGs (66%) and a cautery device cut the fenestration in 484 (75%) PMSGs. No bridging stent was used in 47 (7.0%) PMSGs (these aa-PMSGs had large fenestrations). Technical success ranged from 87.5% to 100% and 30 day mortality from 0% to 8%. Primary branch patency ranged from 96.3% to 100% at 12 month follow up. Zero to 14% of patients experienced type 3 or type 1 endoleak at 14.8 month follow up.

CONCLUSION

PMSG is a useful technique, particularly when validated treatments are not available. However, it is a non-standardised technique and the long term consequences of modifications remain unknown.

Optimal In Situ Fenestration Technique With Laser Perforation and Balloon Dilation for Aortic Stent-Grafts

PURPOSE

To evaluate the response of various stent-grafts after laser fenestration and dilation with noncompliant balloons to determine the optimal therapeutic combination for this treatment technique.

MATERIALS AND METHODS

Five aortic stent-grafts were evaluated ex vivo: the Bolton RelayPlus, Jotec E-vita Thoracic 3G, Medtronic Valiant, Cook Zenith Alpha, and Vascutek Anaconda. Small holes were created using an excimer laser with the grafts submerged in saline. Five rows of 5 fenestrations were created, 4 holes in each row were dilated once with a 6-, 8-, 10-, or 12-mm-diameter noncompliant balloon to the specified nominal pressure (one hole served as the control). The saline solution from each stent-graft was collected and qualitatively analyzed for debris. The fenestrations were evaluated under light and scanning electron microscopes. The maximum diameter and area for each fenestration were measured. The direction and length of tears were assessed.

RESULTS

The fenestration was feasible and reproducible in all the stent-grafts. The mean area of fenestration ranged from 7.63±1.63 to 14.75±0.73 mm² when using balloons of 6- and 8-mm diameter, respectively. The 10- and 12-mm-diameter balloons caused a significant increase in area, variability, and tearing. The Anaconda graft tended to tear in the weft direction, while the other devices tore in the warp direction when using the 10- and 12-mm-diameter balloons. Dilation of the RelayPlus and Anaconda grafts with 6- and 8-mm-diameter balloons provided minimal tearing and precise fenestrations. Melted fiber remnants were observed after filtration of the saline solution for all devices.

CONCLUSION

Laser fenestration and dilation with noncompliant balloons is a relatively simple and reproducible option for revascularization in urgent, complex aortic endovascular repairs. In our model, large balloons (ie, >10 mm) increased the destruction and tearing of the fabric. The maximum dilation recommended is 6 to 8 mm to avoid significant tears. Development of stent-grafts or novel fabrics designed explicitly for fenestration is needed to reduce potential complications.

Recanalization and Stenting of the Celiac and the Superior Mesenteric Artery Supported by Use of a Steerable Introducer Sheath: Report on 2 Years' Experience

PURPOSE

To compare technical parameters and success of recanalization of celiac (CA) or superior mesenteric artery (SMA) with usage of steerable vs not steerable introducer sheaths.

METHODS

A retrospective analysis was performed on all consecutive patients who underwent recanalization with stent implantation of CA or SMA between 2015 and 2019. Data regarding technical success (successful stent placement with restoration of sufficient blood flow by the first attempt without changing kind of introducer sheath or access site), indication for treatment, vascular access, kind of introducer sheath, fluoroscopy time and radiation dose were collected. Preinterventional CT were analyzed to classify the difficulty of catheterization of target vessels. Technical parameters were compared with independent t-test (p ≤ 0.05).

RESULTS

66 patients underwent recanalization of CA or SMA. Usage of steerable introducer sheaths was associated with higher technical success compared to not steerable introducer sheaths with transfemoral approach respectively of 8/8 vs 15/19 for the CA and 11/11 vs 17/20 for the SMA. Steerable introducer sheaths were used in recanalization considered more technically difficult compared to not steerable introducer sheaths (58% vs 33%). Usage of steerable introducer sheath showed a statistically significant reduction of radiation dose in the recanalization of the SMA (respectively 32035 ± 15716 cGy cm² vs 60102 ± 28432 cGy cm²; p = 0.005).

CONCLUSION

Even if used in more difficult interventions, steerable introducer sheaths showed a higher technical success compared to not steerable introducer sheaths with transfemoral access.

Combination of Quadruple Antegrade and Retrograde In Situ Stent-Graft Laser Fenestration in the Management of a Complex Abdominal Aortic Aneurysm

BACKGROUND

We report a case of juxtarenal abdominal aortic aneurysm-anatomically unsuitable for conventional endovascular repair because of narrow distal aorta-successfully treated by endovascular repair facilitated by in situ laser fenestration.

METHODS AND RESULTS

An aortic stent graft was inserted to exclude a juxtarenal aneurysm: under image fusion guidance, antegrade in situ laser fenestration allowed to perfuse superior mesenteric artery and both renal arteries. After complementary insertion of an extended aortouni-iliac stent graft, retrograde in situ laser fenestration was performed to perfuse the contralateral left iliac artery, in order to overcome a narrow distal aorta. Postoperative course was uneventful. Six month's CT showed an excluded aneurysm, patency of the inserted stents and the absence of endoleak.

CONCLUSIONS

In situ laser fenestration seems to be an effective solution for endovascular therapy of complex juxtarenal aneurysms. In this case of narrow distal aorta it was a suitable alternative to overcome endovascular aneurysm repair anatomical restrictions and to prevent other additional open surgical interventions.

Experimental Analysis of the Quality of Needle-Assisted Fenestration in Aortic Stent-Grafts and the Differences Between Gradual and Rapid Balloon Dilation

Purpose: To report the findings of an in vitro experiment to evaluate the quality of needle fenestrations dilated by different size balloons in various stent-grafts and to investigate the differences between gradual and rapid dilation. Materials and Methods: Fenestrations were made using an 18-G needle in 5 different polyester or expanded polytetrafluoroethylene (ePTFE) stent-grafts: Relay, Valiant, Hercules, TAG, and Ankura. Each stent-graft received 2 groups of fenestrations: one was followed by gradual sequential dilation (4-, 6-, 8-, and 10-mm balloons) and the other by rapid dilation (4- and 10-mm balloons). The pressure was increased to 10 atmospheres or until the balloon was fully inflated with no waist. Quantitative and qualitative evaluations, including fenestration diameter, area, shape, and margins were conducted using light microscopy and scanning electron microscopy. Results: Relay had the strongest resistance to dilation and Ankura the slightest. The maximum length and area of holes expanded as the balloon diameter increased. The fenestrations in polyester devices were mostly elliptical or slit-like, with limited tears but extensive fibers visible in the margin, while ePTFE stent-grafts showed larger fenestration areas with clearer margins. Ankura showed the best quality of fenestrations, which were always circular or square without fabric tears, while the holes in the TAG were square or elliptical but sometimes had a slit after large balloon dilation (≥6 mm). The Relay, Valiant, Hercules, and Ankura devices showed no difference in maximum diameter, fenestration area, or scores of shape and margin (p>0.05). Rapid dilation in the TAG increased the rate of uncontrolled fabric tear, resulting in a larger final diameter (12.90 vs 10.82 mm, p=0.047), smaller area (30.46 vs 41.09 mm2, p=0.028), worse shape (0.75 vs 1.20, p=0.268), and worse margin (0.40 vs 1.00, p=0.174). Though the decreased fenestration shape and margin scores did not reach statistical significance, the trend for decline was more obvious than with the other devices. Conclusion: Materials and structures of the stent-grafts determine the quality of fenestrations dilated by different size balloons. The use of sequential vs rapid balloon dilation is also crucial for fashioning high-quality fenestrations and should be selected judiciously.

Antegrade in situ fenestrated endovascular repair of a ruptured thoracoabdominal aortic aneurysm

We describe a technique for antegrade in situ laser fenestration that has several advantages in the setting of ruptured thoracoabdominal aortic aneurysms. This technique involves rapid aneurysm sealing by deployment of aortic stent graft, followed by sequential incorporation of branch vessels using a laser probe through steerable sheath. The advantages of this technique include (1) rapid seal of the ruptured aneurysm, (2) preservation of the visceral and renal branch perfusion, (3) use of an off-the-shelf device, and (4) the ability to be performed without general anesthesia.

Gutter Characteristics and Stent Compression of Self-Expanding vs Balloon-Expandable Chimney Grafts in Juxtarenal Aneurysm Models

Purpose: To assess in silicone juxtarenal aneurysm models the gutter characteristics and compression of different types of chimney graft (CG) configurations. Materials and Methods: Fifty-seven combinations of Excluder C3 or Conformable Excluder stent-grafts (23, 26, and 28.5 mm) were deployed in 2 silicone juxtarenal aneurysm models with 3 types of CGs: Viabahn self-expanding (VSE; 6 and 13 mm) or Viabahn balloon-expandable (VBX; 6, 10, and 12 mm) stent-grafts and Advanta V12 balloon-expandable stent-grafts (ABX; 6 and 12 mm). Setups were divided into 4 groups on the basis of increasing CG and main graft (MG) diameters. Two independent observers assessed gutter size and type as well as CG compression on computed tomography scans using postprocessing software. Results: In the smaller diameter combinations (6-mm CG and 23-, 26-, and 28.5-mm MGs), both VSE (p=0.006 to 0.050) and ABX (p=0.045 to 0.050) showed lower gutter areas and volumes compared with VBX. In turn, the VBX showed a nonsignificant tendency to decreased compression, especially compared to ABX. Use of the Excluder C3 showed a 6-fold increase in type A1 gutters (related to type Ia endoleak) as compared to the Conformable Excluder (p=0.018). Balloon-expandable stent-grafts (both ABX and VBX) showed a 3-fold increase in type A1 gutters in comparison with self-expanding stent-grafts (p=0.008). Conclusion: The current study suggests that use of the Conformable Excluder in combination with VSE chimney grafts is superior to the other tested CG/MG combinations in terms of gutter size, gutter type, and CG compression.

Acute Kidney Injury after Complex Endovascular Aneurysm Repair

Background:

Complex endovascular repair of abdominal aortic aneurysm carries higher perioperative morbidity than standard infrarenal endovascular repair.

Objective:

This study reviews the incidence and associated factors of acute kidney injury in complex aortic endovascular repair of juxtarenal, pararenal, and thoracoabdominal aortic aneurysms.

Methods:

A literature review was performed for all studies on the endovascular repair of juxtarenal, pararenal, and thoracoabdominal aneurysms that evaluated rates of acute kidney injury as an outcome. Outcomes were further analyzed by the level of anatomic complexity and method of repair.

Results:

52 studies met inclusion criteria, with a total of 5454 individuals undergoing repair from 2004 to 2017. The overall rate of acute kidney injury ranged widely from 0 to 41%, with a rate of hemodialysis from 0 to 19% (temporary) and 0 to 14% (permanent). Increasing anatomic complexity was associated with higher rates of acute kidney injury. Mode of endovascular repair, learning curve effect, and preoperative chronic renal insufficiency did not demonstrate any associations with the outcome.

Conclusion:

Published rates of acute kidney injury in complex aortic aneurysm repair vary widely with few definitively associated factors other than increasing anatomic complexity and operative time. Further study is needed for the identification of predictors related to postoperative acute kidney injury.

Consecutive failing proximal landing zones

We report the case of a 77-year-old man who presented with successive aortic aneurysms during a 12-year period. He was first treated in 2006 for an abdominal aortic aneurysm with a bifurcated endograft, then in 2016 for a tender type IV thoracoabdominal aortic aneurysm with a proximal aortic cuff with in situ laser fenestrations. He presented in 2018 with a 9-cm distal thoracic aorta aneurysm managed by an off-the-shelf t-Branch endograft (Cook Medical, Bloomington, Ind). The perioperative course was uneventful, and 6-month follow-up computed tomography scan has shown freedom from endoleaks and branch patency. This case illustrates that apparently “healthy” aortic necks can degenerate after endovascular aneurysm repair.

A Novel Internal and External Bypass Method to Safeguard Cerebral Blood Flow During Aortic Arch Endovascular Repair Requiring Triple In Situ Fenestrations

Purpose: To report a novel internal and external blood bypass method for cerebral protection during in situ triple-fenestrated stent-graft repair in the aortic arch. Technique: A method was devised to combine internal and external blood bypass circuits to preserve cerebral blood flow when all 3 supra-aortic branches are covered by the stent-graft. Long 14-F to 18-F introducers are placed retrogradely into the right and left common carotid arteries (CCAs). Smaller sheaths are placed antegradely into the internal carotid arteries (ICAs) bilaterally and into the right CCA introducer, which has had an aperture cut into it for flow to pass into the smaller sheath. The right CCA introducer is positioned in the ascending aorta to supply the innominate artery; the smaller sheath in the right CCA introducer is positioned at the aperture. The small sheath in the right CCA is connected to the left ICA sheath, and the left CCA fenestration is made and stented. The left ICA sheath is connected to the right ICA sheath, and the right CCA introducer is pulled back to the origin of the innominate artery and the smaller sheath removed. The fenestrations for the innominate and left subclavian arteries are opened sequentially. In 8 patients, complete bypass to maintain brain perfusion was performed for an average 17.6±6.9 minutes; intraoperative transcranial Doppler monitoring during flow bypass showed no notable decline in intracranial blood flow velocity. Two patients suffered stroke; one recovered completely. Conclusion: A cerebral protection strategy that integrates internal and external blood flow bypass techniques to maintain adequate brain blood flow is simple and feasible for in situ triple-fenestration aortic arch stent-graft repairs. However, neurological complications were not avoided with this method; thus, further research and development are required.

Should endovascular approach be considered as the first option for thoraco-abdominal aortic aneurysms?

Open surgical repair has been the gold standard for treatment of thoracoabdominal aortic aneurysms (TAAAs). The technique of open TAAA repair has evolved from the use of "island" patch incorporation to separate branch vessel bypass, from "clamp and go" to routine use of distal perfusion, and towards more extensive repair in patients with connective tissue disorders. Open TAAA repair can be done with excellent results in highly specialized centers. However, these operations continue to carry excessive risk when performed outside large aortic centers, with 30-day mortality estimated on 20% according to statewide and national databases. In octogenarians, the mortality of elective open TAAA repair can be up to 40%. Endovascular repair was introduced as an alternative to open surgical repair in the elderly or higher risk patients using hybrid reconstruction, parallel grafts or fenestrated and branched endografts. Several large aortic centers have developed dedicated clinical programs to advance techniques of fenestrated-branched endovascular repair using patient-specific and off-the-shelf devices, offering a minimally invasive alternative to open repair allowing treatment of increasingly older and sicker TAAA patients. During the last decade, improvements in device design, patient selection, spinal cord injury protocols, and perioperative management have contributed to a continued decline in morbidity and mortality of fenestrated-branched endovascular aortic repair, challenging open surgical repair as the new "gold standard" for treatment of TAAAs. Despite the improved results, endovascular repair is a highly technical procedure that requires vast experience, involves a significant risk of complications, and also, has an impact on patients' physical quality of life. In this article, we review the current technical aspects of endovascular TAAA repair with the main focus on the evidence of open versus endovascular outcomes of TAAA repair.

A novel all-retrograde approach for t-Branch implantation in ruptured thoracoabdominal aneurysm

The off-the-shelf t-Branch device (Cook Medical, Bloomington, Ind) significantly advanced the endovascular treatment of ruptured thoracoabdominal aortic aneurysms. Improved techniques for expeditious implantation of the t-Branch may improve clinical outcomes for this emergent procedure. Currently, implantation is described using axillary and femoral access. We describe the repair of a ruptured thoracoabdominal aortic aneurysm exclusively through femoral access aided by a steerable sheath and newer generation, low-profile bridging stents.