In Situ Laser Fenestrations of Aortic Endografts for Emergent Aortic Disease

Left subclavian artery bridging stent fracture after in-situ laser fenestration during emergent thoracic endovascular aortic repair

In-situ laser fenestration (ISLF) has been described as a viable option for urgent thoracic aortic aneurysm cases involving supra-aortic vessels. There are, however, limited data on its durability. Here, we present a case of a 70-year-old man with a symptomatic 13-cm thoracic aortic aneurysm extending proximally to the origin of the left subclavian artery (LSA). Emergent thoracic endovascular aortic repair with chimney stenting of the left common carotid artery and ISLF for the LSA was successfully performed. During the follow-up, a compression of the bridging stent to the LSA progressed to a stent fracture needing realignment. Despite ISLF's reported technical success, this case highlights the risk of bridging stent complications, emphasizing the need for a close follow-up.

Assessment of Bridging Stents in In Situ Laser Fenestrations of Aortic Endografts With Intravascular Ultrasound

Objective

Treatment of complex aortic aneurysms with the in situ laser fenestration (ISLF) technique involves implantation of a balloon expandable stent graft (bSG) in the created fenestration. Adequate expansion of this bSG is of importance both to achieve seal and to ensure target vessel stability. This experimental study assessed the expansion rate of different bSGs in the ISLF setting using intravascular ultrasound (IVUS).

Methods

A commercially available aortic endograft was used to test the laser fenestration technique (Zenith Alpha, Cook Medical LLC, Bloomington, IN, USA). The ISLF was stented with the following bSGs: two Gore Viabahn VBX balloon expandable endoprostheses (WL Gore & Associates, Bloomington, IL, USA), three BeGraft Peripheral and three BeGraft Plus (Bentley InnoMed GmbH; Hechingen, Germany), and three Advanta V12 (Atrium, Hudson, NH, USA). The bSGs were expanded in three steps: (1) nominal, (2) rated burst pressure, and (3) dilation with a non-compliant balloon at 15 atmospheres. After each step, an IVUS assessment of the bSG minimum diameter and the area at the fenestration (FA) and in a fully expanded segment distal to the fenestration (SA) was performed. A mean of the three IVUS measurements was used as the value for comparison. An insufficient bSG expansion was defined as a mean of FA/SA of <0.8 (i.e., <80% expansion).

Results

The VBX was the only bSG that could be expanded to its intended diameter (i.e., at least 80%) at nominal pressure. The BeGraft Peripheral and BeGraft Plus had the lowest degree of expansion after nominal and rated burst pressure. All bSGs that were tested reached a sufficient expansion degree after using a higher pressure balloon.

Conclusion

In this ex vivo experiment, dilation up to nominal pressure showed satisfactory expansion only for the VBX. The consistency of the results when applied to the different types of stent grafts that were analysed reflects structural stent graft specific issues to consider when choosing the right device in cases of ISLF.

In situ laser fenestration of the Thoraflex Hybrid frozen elephant trunk for emergent revascularization of the left subclavian artery and laser fenestration for spinal cord perfusion

In situ laser fenestration (ISLF) has emerged as a promising technique for emergent revascularization of the left subclavian artery in the case of thoracic endovascular aortic repair coverage, presenting excellent technical success rates in most studies. We describe a case of ISLF of the Thoraflex Hybrid frozen elephant trunk device to achieve immediate left subclavian artery revascularization. We demonstrate the feasibility and technical success of using ISLF in this setting, providing a less invasive alternative to conventional surgical revascularization when required.

Hospital Incidence, Sex Disparities, and Perioperative Mortality in Open Surgically Treated Patients with Aneurysms of the Ascending Aorta and Aortic Arch in Switzerland

OBJECTIVE

To analyze the epidemiological shifts in the incidence of ascending and arch aortic aneurysms (AA) treated with open surgery in the context of evolving endovascular options on a national basis.

METHODS

Between 1 January 2009 and 31 December 2018, 4388 cases were admitted to the hospital with either ruptured (r)AA or non-ruptured (nr)AA as the primary or secondary diagnosis. Patients were classified as having AA based on inclusion and exclusion criteria.

RESULTS

The age-standardized hospital incidence rates for treatment of nrAA were 7.8 (95% confidence interval (CI): 6.9 to 8.7) in 100,000 men and 2.9 (2.4 to 3.4) in 100,000 women and were stable over time. The overall raw in-hospital mortality rate was 2.0% and was significantly lower in males compared to women (1.6% vs. 2.8%, p = 0.015). Higher van Walraven scores (OR: 1.08 per point; 95%CI: 1.06 to 1.11; p = 0.001) and higher age (OR 1.05 per year; (95%CI: 1.02 to 1.07, p = 0.045) were significantly associated with hospital mortality.

CONCLUSIONS

Endovascular surgery seems to have no influence on hospital incidence in patients treated with conventional surgery for AA in Switzerland. There was a significant reduction in in-hospital mortality in both men and women, with age and the von Walraven score being independent factors for worse outcomes.

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.

Urgent endovascular mycotic aortic arch aneurysm repair using in situ laser fenestration and selective arterial perfusion with venoarterial extracorporeal membrane oxygenation

In recent years, mycotic aortic aneurysms have been increasingly treated successfully by endovascular means. The introduction of custom-made fenestrated and branched devices, parallel graft techniques, and in situ fenestration has enabled total endovascular treatment also for arch pathologies. We describe a total endovascular repair of a mycotic arch aneurysm with in situ laser fenestration using venoarterial extracorporeal membrane oxygenation to preserve flow to vital organs.

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).

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.

Descending thoracic aortic emergencies: Past, present, and future

The most important descending thoracic aortic (DTA) pathologies are aneurysms, dissections, and traumatic injuries. In acute settings, these conditions can constitute a significant risk of bleeding or ischemia of vital organs, resulting in a fatal outcome. Morbidity and mortality associated with aortic pathologies remain significant, despite improvements in medical therapy and endovascular techniques. In this narrative review, we present an overview of the transitions in the management of these pathologies and discuss current challenges and future perspectives. Diagnostic challenges include differentiating between thoracic aortic pathologies and cardiac diseases. Efforts have been made to identify a blood test that can rapidly differentiate these pathologies. Computed tomography is the cornerstone of diagnosing thoracic aortic emergencies. Our understanding of DTA pathologies has improved substantially due to the significant advancement in imaging modalities in the last 2 decades. On the basis of this understanding, the treatment of these pathologies has been revolutionized. Unfortunately, robust evidence from prospective and randomized studies is still lacking for the management of most DTA diseases. Medical management plays a crucial role in achieving early stability during these life-threatening emergencies. This includes intensive care monitoring, heart rate and blood pressure control, and considering permissive hypotension for patients presenting with ruptured aneurysms. Over the years, surgical management of DTA pathologies changed from open repair to endovascular repair with dedicated stent-grafts. Techniques in both spectrums have improved substantially.