Endovascular Repair of Ruptured Abdominal Aortic Aneurysms Using the Endurant™ Endograft.

Background: Endovascular aortic aneurysm repair (EVAR) represents a valid treatment modality for ruptured abdominal aortic aneurysms (rAAAs). This study aimed to present rAAA outcomes treated by EVAR using the Endurant endograft. Methods: A single-center retrospective analysis of consecutive patients treated with standard EVAR (sEVAR) or parallel graft (PG)-EVAR for infra- or juxta/para-renal rAAA using the Endurant endograft (1 January 2008-31 December 2023) was undertaken. The primary outcomes were technical success, mortality, and reintervention. Follow-up outcomes, including survival and freedom from reintervention, were assessed using Kaplan-Meier estimates. Results: Eighty-eight patients were included (87.5% sEVAR and 12.5% PG-EVAR). The mean aneurysm diameter was 73.3 ± 19.3 mm (71.4 ± 22.2 mm sEVAR and 81.7 ± 33.0 mm PG-EVAR). Among 77 patients receiving sEVAR, 26 (33.8%) received an aorto-uni-iliac device. All PG-EVAR patients were managed with bifurcated devices, one receiving a single PG, seven double PGS, and three triple PGs. Technical success was 98.8% (100.0% sEVAR and 90.9% PG-EVAR). The 30-day mortality was 47.2% (50.7% sEVAR and 27.3% PG-EVAR), with nine (10.2%) deaths recorded on the table. The mean time of follow-up was 13 ± 9 months. After excluding 30-day deaths, the estimated survival was 75.5% (standard error (SE) 6.9%) at 24 months. The estimated freedom from reintervention was 89.7% (SE 5.7%) at 24 months. Only one endoleak type Ia event was recorded during follow-up. Conclusions: Endurant showed high technical success rates and low rates of endoleak type Ia events and reinterventions, despite the emergent setting of repair. rAAA is still a highly fatal condition within 30 days, with an acceptable mid-term survival of 30-day survivors at 75.5%.

Computational study of fenestration and parallel grafts used in TEVAR of aortic arch aneurysms.

To explore the differences between fenestration technique and parallel grafts technique of thoracic endovascular aortic repair, and evaluate the risk of complications after interventional treatment of aortic arch aneurysms. A three-dimensional aortic model was established from the follow-up imaging data of patient who reconstructed the superior arch vessel by the chimney technique, which was called the chimney model. Based on the chimney model, the geometric of the reconstructed vessel was modified by virtual surgery, and the normal model, fenestration model and periscope model were established. The blood flow waveforms measured by 2D phase contrast magnetic resonance imaging were processed as the boundary conditions of the ascending aorta inlet and the superior arch vessels outlets of the normal model. The pressure waveform of descending aorta was obtained using three-element Windkessel model, and specific pressure boundary conditions were imposed at reconstructed branches for the postoperative models. Through computational fluid dynamics simulations, the hemodynamic parameters of each model were obtained. The reconstructed vessel flow rate of the periscope model and the fenestration model are 33% and 50% of that of the normal model, respectively. The pressure difference between the inner and outer walls of the fenestration stent and periscope stent is 3.15 times and 7.56 times that of the chimney stent. The velocity in the fenestration stent and periscope stent is uneven. The high relative residence time is concentrated in the region around the branch stents, which is prone to thrombosis. The "gutter" part of the chimney model may become larger due to the effect of the stent-graft DF, increasing the risk of endoleak. For patients with incomplete circle of Willis, the periscope technique to reconstruct the supra-arch vessels may affect blood perfusion. It is recommended to use balloon-expandable stent for fenestration stent and periscope stent, and self-expanding stent for chimney stent. For patients with aortic arch aneurysms, the fenestration technique may be superior to the parallel grafts technique.

Salvage of an Incomplete Sandwich With a Covered Celiac Trunk and a "Floating" Superior Mesenteric Artery Stent in a Thoracoabdominal Aortic Aneurysm.

PURPOSE: To report a case of a patient with a large thoracoabdominal aortic aneurysm (TAAA) extent V treated with a custom-made fenestrated and branched endovascular repair (F/B-EVAR) after a failed and incomplete attempt of a Sandwich repair technique. REPORT: An 83-year-old patient was referred to our department after a failed attempt at endovascular repair of type V TAAA with a sandwich technique. The celiac trunk was inadvertently covered with the first endograft and a covered long superior mesenteric artery stent was placed and left facing upward inside the aorta. We performed a staged repair, by first catheterizing and stenting the celiac trunk and bringing it under and inside the main aortic endograft. In interval, a F/B-EVAR was performed using a bimodular custom-made device (CMD) with a proximal 2 branch module for the celiac trunk and superior mesenteric artery and distal module with fenestrations for both renal arteries. The intervention was successful, and the follow-up was uneventful at 6 months. CONCLUSIONS: Re-intervention after failed endovascular attempts of TAAA repair are technically challenging and require advanced endovascular techniques. The ability to construct CMDs allowed to extend repair to our patient which had severe anatomical constraints for other techniques.

Parallel grafts and physician modified endografts for endovascular repair of the aortic arch.

Aortic arch aneurysms are a challenging clinical problem especially in high-risk patients. Open aortic arch replacement, even in the best of centers, carries significant risk of stroke or death in this high-risk population. Many high-risk patients are deemed inoperable and not offered repair. Branched and fenestrated thoracic endografts are currently undergoing clinical trials in the United States but are not yet commercially available. Many elderly and frail patients have significant brachiocephalic occlusive disease or anatomy excluding them for consideration for such clinical trials. These patients also present with acute aortic syndromes requiring urgent or emergent repair and are unable to participate in clinical trials due to the time required to have such devices available. Alternative endovascular therapies, including parallel stent grafts (including Chimneys, Snorkels and Periscopes) and physician modified thoracic endografts, have been used to treat such high-risk patients combined with commercially available thoracic endovascular aneurysm repair (TEVAR) devices. This paper aims to review the techniques and current reported outcomes from parallel stent grafts and physician modified devices used to treat high risk patients undergoing repair for aortic arch pathologies.

Long-term results of total endovascular repair of arch-involving aortic pathologies using parallel grafts for supra-aortic debranching.

OBJECTIVE: We evaluated the long-term morphologic and clinical outcomes after thoracic endovascular aortic repair combined with parallel grafts (PG-TEVAR) for arch-involving aortic pathologies. METHODS: We performed a retrospective analysis of perioperative and follow-up data of patients who had undergone PG-TEVAR at a single vascular surgery center from November 2010 to April 2018. Patients with prior or simultaneous open chest or cervical debranching procedures or arch repair were excluded. The primary endpoint was freedom from overall PG-TEVAR-related reintervention. The secondary endpoints were parallel graft sealing zone failure (presence of gutter-related type I or Ic endoleak), PG failure (occlusion or reintervention), stroke, and 30-day and overall PG-TEVAR-related and all-cause mortality. Kaplan-Meier curves were used to estimate the freedom from reintervention and survival. Receiver operating characteristics curves were used to find the optimal cutoff to prevent type Ia endoleak-related reintervention. RESULTS: A total of 33 patients, including 8 women, with a median age of 74 years (interquartile range, 67-79 years) had undergone PG-TEVAR (chimney, periscope, and sandwich in 20, 15, and 13 patients, respectively) with proximal landing in Ishimaru zone 0, 1, or 2 in 4, 5, and 24 patients, respectively. The aortic pathologies included type B aortic dissection (acute and chronic, eight and six, respectively), degenerative aneurysm (n = 10), type Ia endoleak (n = 3), para-anastomotic/patch aneurysm (n = 4), left subclavian artery aneurysm (n = 1), and traumatic rupture (n = 1). The perioperative stroke rate and 30-day mortality was 6% and 9%, respectively. Direct postoperative computed tomography revealed 28 endoleaks (gutter-related type Ia, 12; gutter-related type Ib, 9; type Ia, 2; type Ic, 2; type III, 1; undetermined, 2) in 27 patients. The technical and clinical success rate was 37% and 30%, respectively. The mean follow-up for survival was 48 ± 31 months. The latest radiologic follow-up demonstrated 12 remaining and 1 new endoleak. The early and overall PG sealing zone failure and PG failure was 73% and 36% and 9% and 18%, respectively. The overall PG-TEVAR-related reintervention rate was 33% (n = 11). The estimated freedom from overall PG-TEVAR-related reintervention was 68% at 60 months. The main graft oversizing and length oversizing rates were not significantly associated statistically with the type Ia endoleak-related reintervention rate. The PG-TEVAR-related and all-cause mortality were 18% and 34%, respectively. CONCLUSIONS: PG-TEVAR for total endovascular repair of arch-involving aortic pathologies resulted in a high rate of type I endoleaks and the need for long-term reintervention. Gutter-related endoleaks might be more frequent than reported and should not be underestimated because they can lead to sac enlargement and reintervention. Frequent radiologic surveillance is mandatory. Further studies comparing PG-TEVAR to other total endovascular alternatives are required to confirm these findings.

Early and Mid-Term Outcomes of Open versus Endovascular Left Subclavian Artery Debranching for Thoracic Aortic Diseases.

PURPOSE: To compare open versus endovascular left subclavian artery debranching for thoracic endovascular aortic repair of thoracic aortic pathologies. METHODS: This is a retrospective study of patients receiving left subclavian artery debranching in our institution from October 2009 to January 2020. The primary outcome was freedom from aortic reintervention. Secondary outcomes were type I endoleaks, left subclavian artery (LSA) debranching failure, stroke, technical or clinical success, procedure-related reintervention, as well as 30-day or overall all-cause and aorta-related mortality. RESULTS: Forty-eight patients received parallel graft-based (n = 24, ENDO; median age 75 years [70-80 years]) or open (n = 24, OPEN; median age 71 years [59-75 years]) debranching for type B aortic dissection (n = 25), degenerative aneurysm (n = 12), type IA endoleak (n = 6), suture-associated (n = 3) or ostial LSA aneurysm (n = 1), or penetrating aortic ulcer (n = 1). The median follow-up was 36 months (13-61 months). After 16 months, aortic reintervention-free survival in groups OPEN and ENDO was 91% (95% confidence interval [CI]: 79 to 100%) and 86% (73 to 100%) (p = 0.71), respectively. After 36 months, all-cause survival in groups OPEN and ENDO was 74% (95% CI: 55 to 99%) and 79% (95% CI: 64 to 97%) (p = 0.74), respectively; freedom from aorta-related mortality was 81% (95% CI: 62 to 100%) and 91% (95% CI: 80 to 100%) (p = 0.78), respectively. Group OPEN presented less type I endoleaks (OPEN/ENDO = 3/19, p <0.001) and higher technical (OPEN/ENDO = 81/36%, p = 0.003) and clinical success rates (OPEN/ENDO = 67/36%, p = 0.047). No statistical differences were found for other outcomes. CONCLUSION: Both strategies achieved comparable reintervention and mortality rates, but open debranching should be preferred due to its higher technical and clinical success and less type I endoleaks.

Use of Stainless-Steel, Balloon-Expandable Chimney Grafts Is Durable Though Caution Is Required When Lining Angulated Renal Arteries.

PURPOSE: To analyze the overall performance of flexible nitinol stents used to line chimney grafts (CGs) during chimney endovascular aneurysm repair (chEVAR) of pararenal pathologies. MATERIALS AND METHODS: A retrospective review was conducted of all 116 elective patients (mean age 74.3±7.2 years; 103 men) who underwent chEVAR with balloon-expandable Advanta V12/iCAST CGs in combination with the Endurant stent-graft between January 2009 and December 2017 at a single center. CG lining with a nitinol stent was electively performed in 43 target vessels of 32 patients. The Kaplan-Meier method was used to estimate the primary outcomes of CG patency and freedom from reintervention (FFR) at the patient level and according to the use of a stent to line the CG. Estimates are reported with the 95% confidence interval (CI). Adjusted odds ratios (ORs) were calculated to identify any confounding effect between the presence/absence of a stent lining or according to the number of CGs. RESULTS: The mean radiological follow-up was 27.3 months (range 22.1-32.6). During this time, 8 CGs (4.7%) became occluded, 6 of them were lined with stents. Restoration of patency was possible in 3 of the 4 occluded stents that were associated with symptoms. First-year primary patency estimates were 96.9% (95% CI 92.5% to 100%) for the unlined group vs 77.1% (95% CI 58% to 95.3%; p=0.001) for the lined group, while FFR was 87.6% (95% CI 79.9% to 95.2%) vs 83.4% (95% CI 68.1% to 98.6%; p=0.82), respectively. Lining represented an independent risk factor for CG occlusion (OR 9.9, p=0.006). CONCLUSION: CG lining performed mainly in angulated renal arteries during chEVAR was significantly associated with CG occlusion. These findings highlight the importance of not having the distal part of the CG impinge on the angulated segment of the target vessel.

Endovascular Hybrid Repair of True Ascending Aortic Aneurysms Using Double Graft Wrapping to Prepare a Landing Zone for Ascending Aortic Stent-Graft Placement: A Cohort Study.

Purpose: To describe a hybrid procedure that avoids cardiopulmonary bypass to treat patients with true ascending aortic aneurysms without a suitable proximal landing zone for endovascular repair. Material and Methods: Thirteen consecutive patients (mean age 75.9±6.5 years; 8 women) with true ascending aortic aneurysms were treated with the endovascular hybrid repair of true aortic aneurysms (EHTA) approach, which consists of a conventional sternotomy with double wrapping of the ascending aorta followed by staged stent-graft placement. Via sternotomy, a polypropylene mesh trimmed to downsize the aneurysm is placed around the dilated ascending aorta and sutured to the adventitia. A similarly trimmed polytetrafluoroethylene graft is placed loosely around the first wrap to avoid adhesions and secure the proximal landing zone. There is no need for cardiopulmonary bypass. A few days later, a standard thoracic stent-graft is deployed via either a transaxillary or transfemoral access; chimney or bypass grafts are used as needed to revascularize the supra-aortic vessels. Results: The ascending aortic diameter was reduced from a mean 5.7 cm (range 4.8-6.5) to 3.9 cm (range 3.2-4.3) after wrapping. The mean interval between surgery and stent-graft placement was 5 days. In this interval, 2 patients with significant reduction in the diameter of the ascending aorta elected to forego placement of a stent-graft. Of the 11 patients who underwent the full hybrid EHTA procedure, the ascending aortic stent-graft was combined with a chimney graft in the innominate artery in 4 cases. In 1 patient, a supra-aortic debranching procedure using a bifurcated Dacron graft to the innominate and left common carotid arteries was performed after wrapping with the polypropylene mesh. There was no mortality or neurological complication. A sternal wound infection required a prolonged hospital stay. At a mean follow-up of 13.8 months (range 3-24), there has been no death, type I endoleak, or sign of aneurysm enlargement on imaging. Conclusion: This technique permits complete endovascular exclusion of an ascending aortic aneurysm in a less invasive approach than standard open repair. Although this is only a small cohort of patients without long-term follow-up, it seems that this hybrid procedure is associated with low morbidity and mortality. It offers a beating-heart approach to treat true ascending aortic aneurysms in selected high-risk patients.

Chimney parallel grafts and thoracic endovascular aortic repair for blunt traumatic thoracic aortic injuries: A systematic review.

BACKGROUND: Whilst the management of blunt traumatic thoracic aortic injury has seen a paradigm shift to an 'endovascular first' approach, the limitations of thoracic endovascular aortic repair remain. An inadequate proximal landing zone limits the use of thoracic aortic stent grafts and in an emergent polytrauma setting, aortic arch debranching via open surgery may not be practical or feasible. A wholly endovascular approach to debranching utilising 'off-the-shelf' stents and parallel graft techniques may represent a possible solution. Hence, we sought to perform a systematic review investigating the use of chimney graft techniques alongside thoracic aortic stenting in blunt traumatic thoracic aortic injury. METHODS: We performed the systematic review in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Searches were performed on Medline (PubMed), Web of Science and Scopus to identify articles describing the use of chimney grafts in traumatic aortic transection (PROSPERO: CRD42017082549). RESULTS: The systematic search revealed 172 papers, of which 88 duplicates were removed resulting in 84 papers to screen. Based on title, abstract and full text review, six articles were included for final analysis. There were nine patients in total with an average age of 41 (three females, five males, one unspecified), all with significant polytrauma, secondary to the mechanism of injury. A variety of stents were used between centres, with techniques showing a predominance to stenting of the left subclavian artery (77%, n = 7). The technical success rate was 82%, with two (18%) cases of type 1 endoleaks, of which one resolved spontaneously. CONCLUSIONS: Despite the encouraging results, this by no means provides for a firm conclusion given the small sample size. Patients should still be judiciously selected on a case-by-case basis when employing the chimney graft technique. Larger cohort studies are needed to establish these findings.

Simplified hybrid repair with true lumen recycling for retrograde renovisceral perfusion in a complex chronic aortic dissection.

A 59-year-old man was referred with complicated chronic type B aortic dissection. Despite the false lumen's being dominant in terms of caliber and limb perfusion, visceral arteries originated in a 9-mm true lumen. A staged approach was performed: open aortobi-iliac bypass with preservation of both lumens to the infrarenal aorta, with reinforcement of the aorta and anastomosis with Dacron (wrap technique); exclusion of the dissection by endografting all of the false lumen with three successive thoracic endoprostheses; and maintenance of true lumen perfusion using two periscopes with self-expanding nitinol stents. The patient remains asymptomatic after 1 year of follow-up.

Use of the Nellix Endovascular Aneurysm Sealing System in Combination With Parallel Grafts for the Treatment of a Symptomatic Type V Thoracoabdominal Aortic Aneurysm.

PURPOSE: To report endovascular treatment of a symptomatic type V thoracoabdominal aortic aneurysm (TAAA) using the combined techniques of endovascular aneurysm sealing and parallel stent-grafts. CASE REPORT: A 70-year-old man was referred with a symptomatic type V TAAA. The Nellix EndoVascular Aneurysm Sealing (EVAS) System was used in combination with 2 chimney grafts for the celiac artery (CA) and the superior mesenteric artery (SMA); one periscope graft perfused the right renal artery. Completion angiography showed exclusion of the aneurysm and patency of all 3 parallel grafts but occlusion of the left renal artery (LRA) due to unintentional coverage of its ostium by the Nellix endobags. Antegrade catheterization of the LRA failed, requiring implantation of an aortorenal vein bypass. The postoperative course was complicated by acute kidney injury. Imaging at 6 months showed sustained exclusion of the aneurysm, patency of the CA and SMA parallel grafts and left aortorenal bypass but occlusion of the right renal artery periscope graft. Serum creatinine at 6 months was 1.5 mg/dL. CONCLUSION: The combination of EVAS with parallel grafts for preservation of the visceral vessels may be a feasible technique to treat selected TAAAs in the acute setting when other options are not applicable.

Use of the Octopus Endograft Technique to Reconstruct Renovisceral Arteries Arising From the False Lumen of a Rapidly Expanding Type B Aortic Dissection After Endovascular Repair.

PURPOSE: To describe the use and 6-month outcomes of the octopus endograft technique to reconstruct renovisceral arteries arising from the false lumen (FL) of a type B aortic dissection after thoracic endovascular aortic repair (TEVAR). CASE REPORT: A 46-year-old man post TEVAR for type B aortic dissection was admitted with persistent back pain and a rapidly expanding residual dissection. The celiac and left renal arteries arose from the FL and the superior mesenteric artery from both lumens, with the FL as its main supply. A 20% oversized Endurant stent-graft was deployed with the short limb just above the beginning of the dissection flap and the long limb in the aortic true lumen. A 120-mm-long Endurant extended limb was delivered antegradely via a conduit and deployed into the FL, with a 3-cm overlap with the short limb of the Endurant main body. The 3 renovisceral arteries were reconstructed by lining each with a series of Viabahn or Fluency stent-grafts whose proximal ends were subsequently placed parallel in the FL Endurant extended limb and dilated with kissing balloons. Imaging at 6 months showed an excluded FL, without stenosis or occlusion in the stent-graft or the renovisceral arteries. CONCLUSION: This case illustrates the successful use of the octopus endograft technique to reconstruct renovisceral arteries arising from a rapidly expanding FL in a post-TEVAR type B aortic dissection; the technique might be applicable in carefully selected patients.

Current evidence regarding chimney graft occlusions in the endovascular treatment of pararenal aortic pathologies: a systematic review with pooled data analysis.

PURPOSE: To review the literature on pararenal endovascular aneurysm repair (EVAR) to determine the frequency and clinical relevance of chimney graft occlusions. METHODS: A comprehensive search of the English-language literature abstracted in the Medline and the Cochrane Library databases was performed to identify case series involving pararenal aortic pathologies (degenerative aneurysms, penetrating atherosclerotic ulcers, type Ia endoleaks, and para-anastomotic aneurysms) treated with EVAR and chimney grafts; thoracoabdominal, iliac, or aortic arch chimney graft placements were excluded, as were case reports in which the total number of chimney grafts implanted at the reporting center could not be determined. The literature search identified 83 studies regarding chimneys/snorkels for pararenal pathologies published between January 2007 and March 2014. Of these, 7 studies met the inclusion criteria and were included in the analysis. RESULTS: There were 15 (4.5%) occlusions in the overall 334 renovisceral vessels in which chimney grafts were deployed. The mean time to chimney graft occlusion was 3.5 months (range 1-270 days) over a mean follow-up of 1.4 months (range 9-24). The target arteries were the renal artery (n=12) and the superior mesenteric artery (SMA; n=3). Seven patients were asymptomatic, and no description was given in 5 cases. In the other 3 patients, the symptoms were acute renal failure, intestinal ischemia, and malignant hypertension. The treatment strategy included open conversion and iliorenal bypass (n=1), exploratory laparotomy to revascularize the SMA (n=1), hemodialysis (n=1), placement of bare metal stents (n=4), conservative treatment (n=2), and unknown (n=6). One (6.7%) patient died (an occluded SMA). Two patients with renal chimney occlusion suffered from temporary renal function deterioration. CONCLUSION: The present analysis identified a low rate of chimney graft occlusions, which appear to occur generally a few months after placement. Involvement of the renal artery had no severe clinical consequences, while occlusion of the SMA can be associated with life-threatening complications. More detailed information regarding occluded chimney grafts will be needed in future publications to help identify the causes.