Multi-branched stent-graft for type III thoracoabdominal aortic aneurysm

Total abdominal debranching hybrid thoracoabdominal aortic aneurysm repair versus chimneys and snorkels

Open thoracoabdominal aortic aneurysm (TAAA) repair remains a surgical challenge. Hybrid and total endovascular repair have emerged as alternatives in treating TAAA. Total endovascular TAAA repair may be best performed with branched/fenestrated stent grafts. However, these technologies are not yet widely available. Thus, currently total endovascular TAAA repair using the chimney/snorkel techniques is considered a viable option in many centers.

In this article, we briefly review 2 readily available techniques with off-the-shelf devices, hybrid procedure using total abdominal debranching, and total endovascular repair using chimney/snorkel procedures. The hybrid TAAA repair avoids thoracotomy but requires laparotomy and carries high morbidity and mortality (eg, operative mortality, 4%-26% and renal failure, 4%-26%), comparable to traditional open repair. The staged hybrid approach has been proposed to minimize the invasiveness of the procedure, whereas the associated risk of interval aortic deaths is not negligible. Total endovascular repair reduces the morbidity and mortality after TAAA repair (eg, operative mortality, 3%-20% and renal failure, 0%-20%). However, it is technically demanding and the risks of future reinterventions—and need for repetitive surveillance—is inevitable (eg, immediate type I endoleak, 7%-16% and 1-year branch patency, 93%-98%). Currently, there are not enough data to determine which less-invasive option for open repair in patients with TAAA is superior. These alternatives should complement each other and be applied to carefully selected populations as a part of the overall toolbox in treating TAAA.

T Branch Repair of Ruptured a Type IV Thoracoabdominal Aortic Aneurysm Complicated by Renal Branch Occlusion

A 60-year male patient presented with a thoracoabdominal aortic aneurysm rupture, which was treated emergently with a modified off-the-shelf t-Branch stent-graft (COOK Medical Inc). The sole renal branch occluded 1 month after TEVAR due to branch compression, and the patient became anuric and temporarily dialysis-dependent. Despite the prolonged renal ischemia time, the occluded renal branch was successfully opened with thrombolysis and reinforced with a bare-metal stent. The patient recovered his renal function and came off dialysis.

Physician-Modified Branched Double-Trunk Stent-Graft (PBDS) for Thoracoabdominal Aortic Aneurysm

PURPOSE

To describe the preliminary experience of using physician-modified, branched, double-trunk stent-grafts (PBDS) for treating thoracoabdominal aortic aneurysms (TAAA).

MATERIALS AND METHODS

Ten (10) patients with TAAA were included in the study from June 2017 to March 2020. The technical success, perioperative complications, re-intervention, and patency of branch arteries were assessed.

RESULTS

The technical success rate was 100%. There were four type III endoleaks (40%) recorded in the perioperative period. The median follow-up was 13.4 months (range, 3-36 months). During follow-up, two renal stent-graft occlusions (2 of 37 visceral arteries reconstructed, 5.4%), one cerebral infarction (1 of 10, 10%) and one paraplegia (1 of 10, 10%) occurred. No aortic-related death was recorded.

CONCLUSION

PBDS is useful in sealing TAAA and preventing visceral branches, providing an option for patients unsuited for open surgical repair. A larger sample size of patients is required to confirm the safety and effectiveness of this technique.

Early Renal Function Alterations in Renal Branches vs. Renal Fenestrations - A Dynamic Scintigraphy Based Prospective Study

OBJECTIVE

The objective of this prospective single centre study was to assess whether branches and fenestrations have different outcomes on renal function in the early phase.

METHODS

From March 2018 to June 2019, 67 patients who underwent elective fenestrated and branched endovascular aneurysm repair (F/BEVAR) procedures were enrolled in this study. The patients were divided into two groups according to the renal bridging component configuration (fenestration vs. branch). All of them underwent dynamic renal scintigraphy with ^99mTc diethylenetriaminepentaacetic acid (DTPA), two weeks pre-operatively, and three months and one year post-operatively. The primary end points were peri-procedural technical success, 30 day major adverse events, differences in glomerular filtration rate (GFR) between the branch and fenestration configurations, and variations between the pre-operative and the post-operative dynamic renal scintigraphy.

RESULTS

Overall, 135 kidneys were analysed: 63 in the 32 patients treated with fenestrations, and 72 in the 35 patients treated with branches; the mean GFR on baseline scintigraphy was 58.4 ± 30.9 mL/min in the fenestration group, and 65.1 ± 29.2 mL/min in the branch group. Only kidneys associated with a patent fenestration/branch were included in the split GFR final analysis. The mean total GFR at three month scintigraphy decreased by 6.0 ± 2.9 mL/min in the fenestration group and by 23.4 ± 6.4 mL/min in the branch group. The split GFR decreased by 3.5 ± 0.6 mL/min in the fenestration group, and by 15.4 ± 5.4 mL/min in the branch group. The GFR decrease remained stable at one year.

CONCLUSION

In this study, the use of branches for renal arteries during F/BEVAR resulted in a greater decrease in the GFR than in those patients who were treated with fenestrations alone. The scintigraphic alterations were evident at an early phase.

Current status of endovascular treatment for thoracoabdominal aortic aneurysms

Open surgical repair (OSR) for thoracoabdominal aortic aneurysms (TAAAs) is maximally invasive and associated with high rates of operative mortality and perioperative complications including spinal cord ischemia (SCI), despite improvements in surgical techniques and perioperative care. Elderly patients, patients with a history of aortic surgery, and patients with severe comorbidities are often considered ineligible for this surgery and endovascular treatment may be their only treatment option. Total endovascular aneurysm repair (t-EVAR) without debranching surgery does not require thoracotomy and laparotomy and could improve the outcomes of these patients. t-EVAR includes fenestrated EVAR (f-EVAR), multi-branched EVAR (b-EVAR), and physician-modified fenestration endograft (PMFG). Although these techniques have achieved lower mortality rates than OSR, there are concerns about perioperative complications including limb ischemia, SCI, and long-term outcomes such as endograft migration and endoleaks (ELs). This article provides an overview of available endovascular devices for TAAAs and reviews the short and mid-term results of t-EVAR, as well as alternative options.

Long-term durability of multibranched endovascular repair of thoracoabdominal and pararenal aortic aneurysms

OBJECTIVE

The objective of this study was to assess the durability of multibranched endovascular repair of thoracoabdominal aortic aneurysms (TAAAs) and pararenal aortic aneurysms by examining the rates of late-occurring (beyond 30 days) complications.

METHODS

There were 146 patients who underwent endovascular TAAA repair using a stent graft, with a total of 538 caudally oriented self-expanding branches. Four patients died in the perioperative period and were excluded, leaving 142 patients (mean age, 73 ± 8 years; 35 [24.7%] women). Follow-up included clinical examination and computed tomography angiography at 1 month, 6 months, and 12 months and yearly thereafter.

RESULTS

Mean aneurysm diameter was 67 ± 9 mm. Sixty-seven TAAAs (47.2%) were Crawford type I, II, III, or V; 75 (52.8%) were type IV or pararenal. Three patients (2.1%) died >30 days after operation from perioperative complications. During a mean follow-up of 36 months (±28 months), there were four additional aneurysm-related deaths: one (0.7%) as a result of aneurysm rupture in the presence of untreatable type I endoleak, one (0.7%) after conversion to open repair for stent graft infection, one (0.7%) after occlusion of superior mesenteric artery and celiac branches, and one (0.7%) due to bilateral renal branch occlusion. There was one additional open conversion for stent graft infection (0.7%). Nineteen patients (13.3%) underwent 20 reinterventions for late-occurring complications, including 11 (7.7%) for renal branch occlusion or stenosis, 1 (0.7%) for mesenteric branch stenosis, 4 (2.8%) for graft limb occlusion, 1 (0.7%) for type IB endoleak (distal stent graft migration), and 1 (0.7%) for type III endoleak (fabric erosion); 2 (1.4%) open conversions were performed for stent graft infection. There were no late type IA endoleaks. By Kaplan-Meier analysis, freedom from aneurysm-related death was 91.1% and freedom from aneurysm-related death or reintervention was 76.8% at 5 years. The 5-year overall survival rate of 49.1% reflects the high rate of cardiopulmonary comorbidity. Although renal branch occlusion (23 occlusions of 256 renal branches [8.9%]) was the most common late complication, only five patients required permanent dialysis.

CONCLUSIONS

Total endovascular repair of TAAAs and pararenal aortic aneurysms using axially oriented cuffs is safe, effective, and durable in the long term.

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

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

Contemporary strategies for repair of complex thoracoabdominal aortic aneurysms: real-world experiences and multilayer stents as an alternative

Thoracoabdominal aortic aneurysms (TAAA) present special challenges for repair due to their extent, their distinctive pathology, and the fact that they typically cross the ostia of one or more visceral branch vessels. Historically, the established treatment for TAAA was open surgical repair, with the first procedure reported in 1955. Endovascular repair of TAAA with fenestrated and/ or branched endografts, has been studied since the beginning of the current century as a means of mechanical aneurysm exclusion. More recently, flow modulator stents have been employed with the aim at reducing shear stress on aortic aneurysmal wall. In this review we present technical and main results of these techniques, based on literature review and personal experience.

Multibranched Stent-Grafts for the Treatment of Thoracoabdominal Aortic Aneurysms

Purpose: To evaluate the available literature on endovascular repair of thoracoabdominal (TAAA) and pararenal aortic aneurysms (PRAA) using multibranched stent-grafts. Methods: MEDLINE, EMBASE, and Cochrane databases were searched between January 2001 and June 2015 to identify articles related to the use of multibranched stent-grafts for the treatment of TAAA and PRAA. Articles with <4 cases and those on juxtarenal aortic aneurysms were excluded. Meta-analyses were conducted to evaluate 30-day mortality, all-cause mortality, spinal cord ischemia, renal insufficiency, endoleak, target vessel patency, and reintervention. Of 370 articles screened, only 4 articles encompassing 185 patients (mean age 71.1 years; 137 men) were aligned with the inclusion criteria. There were 23 PRAAs; the mean aneurysm diameter was 64.5 mm. The Crawford TAAA classification was 10 type I, 47 type II, 37 type III, 58 type IV, and 9 type V; there was 1 Stanford type B dissection in association with a large TAAA. Results of the meta-analyses are reported as proportions and 95% confidence interval (CI). Results: Pooled analysis indicated a technical success rate of 98.9%. As study heterogeneity was significant, random effects models were used for meta-analysis. The rate for 30-day mortality was 9% (95% CI 3% to 19%), for all-cause mortality 27% (95% CI 17% to 38%), endoleaks 10% (95% CI 1% to 25%), target vessel patency 98% (95% CI 95% to 99%), SCI 17% (95% CI 1% to 26%), irreversible SCI 6% (95% CI 3% to 10%), renal insufficiency 15% (95% CI 0.8% to 41%), and reinterventions 21% (95% CI 4% to 47%). Conclusion: Use of multibranched stent-grafts in the treatment of TAAAs and PRAAs appears to be feasible and safe based on satisfactory early outcomes in the limited literature available to date. Long-term surveillance and further studies are essential to determine the durability of this technique.

Visceral branch occlusion following aneurysm repair using multibranched thoracoabdominal stent-grafts

PURPOSE

To identify risk factors for late-occurring branch occlusion following multibranched endovascular repair of thoracoabdominal and pararenal aortic aneurysm.

METHOD

Out of 120 patients who underwent multibranched endovascular aneurysm repair between September 2005 and May 2013, 100 (78 men; mean age 72.4 ± 7.4 years) met the criteria for inclusion in the current retrospective analysis. Demographic data were gleaned from a prospectively maintained database. Mean aneurysm diameter was 66.7 ± 11.7 mm. Multiplanar reconstructions of postoperative computed tomographic angiography were used to measure 6 parameters of renal branch morphology.

RESULTS

All 100 patients had undergone successful placement of multibranched aortic stent-grafts with a total of 95 celiac branches, 100 superior mesenteric artery (SMA) branches, and 187 renal branches. During a mean follow-up of 25.6 months, there were no stent fractures or stent separations, no SMA occlusions, and only 2 (2.1%) celiac artery occlusions, neither of which required reintervention. In contrast, there were 18 (9.6%) renal branch occlusions in 16 patients, all men (p=0.02). Patients with renal branch occlusions were significantly more likely to have a history of myocardial infarction (p=0.004). The mean renal artery length was significantly greater in the occlusion group compared to the non-occlusion group (47.5 ± 13.6 vs. 39.4 ± 14.2, p=0.03). No other aspect of branch morphology was significantly different between the occlusion and non-occlusion groups.

CONCLUSION

Renal branch occlusion was by far the commonest late failure mode after multibranched endovascular aneurysm repair. The current study provides no basis for a change in patient selection or stent-graft design, only a change in the components used to construct renal branches. It is too early to tell the effect this will have.

Current results of endovascular repair of thoraco-abdominal aneurysms†

OBJECTIVES

Fenestrated and branch endografts represent a totally endovascular solution for high-risk patients with atherosclerotic thoraco-abdominal aortic aneurysms (TAAAs). This study reports the early outcome of endovascular TAAA repair.

METHODS

Interrogation of a prospective database of consecutive patients who underwent endovascular repair (EVAR) for TAAA between June 2007 and October 2012.

RESULTS

Sixty-two high-risk patients (55 men; median age 72, range 54-84 years) underwent fenestrated (n = 39) or branch (n = 23) EVAR for non-ruptured TAAA [extent I-III (n = 26) and IV (n = 36)]. Twenty patients had undergone 22 previous aortic procedures. A total of 221 target vessels (coeliac 50, superior mesenteric 61, renal 106, left subclavian 1 and hypogastric 3) were preserved with scallops (n = 17), fenestrations (n = 140) or branches (n = 62) and 201 of these vessels were stent-grafted (coeliac 34, superior mesenteric 58, renal 105, left subclavian 1 and hypogastric 3). The 30-day mortality was 1.6% (n = 1) and one further patient died on postoperative day 62 from respiratory complications. Spinal cord injury (SCI) developed in 5 (8%) patients (3 women and 2 men). Two patients required temporary renal replacement therapy and a further two commenced planned postoperative dialysis.

CONCLUSIONS

In high-risk patients with TAAA, fenestrated and branch EVAR is associated with low early mortality and requirement for renal support, but the risk of SCI is not insignificant despite the use of cerebrospinal fluid drainage and blood pressure manipulation. Our current practice is to stage the repair of extent I-III aneurysms and this has significantly reduced the incidence of SCI.

Endovascular treatment of thoracoabdominal aortic aneurysm: a case report

Introduction

Thoracoabdominal aortic aneurysms usually present in elderly patients with serious renal, pulmonary, cerebral, or cardiac comorbidities that pose a great challenge to the attending surgeon. Endovascular techniques for the treatment of thoracoabdominal aneurysms are not yet widely used due to limitations associated with them, such as spinal and visceral ischemia.

Case presentation

An 87-year-old Caucasian man with a symptomatic Crawford type I thoracoabdominal aortic aneurysm was treated successfully with a long tube stent graft using endovascular techniques and without any complication in follow-up examinations. The stent was placed distal to the left subclavian artery, and proximal to the celiac axis.

Conclusion

The use of endovascular stents for long segment thoracoabdominal aortic aneurysms needs to undergo clinical investigation to determine whether this procedure decreases morbidity and mortality rates.

Recent advances in thoraco-abdominal aortic aneurysm repair

Thoraco-abdominal aortic aneurysm repair remains a formidable challenge to vascular surgeons. The traditional repair of thoraco-laparotomy with aortic cross-clamping is associated with a high morbidity and mortality despite significant advances in perioperative critical care, anaesthetic and surgical techniques. The advent of the endovascular revolution has shown a marked paradigm in the approach to all aneurysm repairs. As a logical progression from the open repair, the St Mary's visceral hybrid repair combines traditional open techniques (retrograde visceral and renal revascularisation via mid-line laparotomy) with endovascular stent grafting, thereby avoiding the need for thoracotomy and aortic cross-clamping. In specialist centres, the results have been encouraging and easily comparable to the open repair. The technique has been used in several centres around the world and represents a robust, transferrable method of repairing thoraco-abdominal aortic aneurysms. Stent-grafting technologies have reached a point of sophistication that wholly endovascular methods of repairing thoraco-abdominal aortic aneurysms are being performed in several centres around the world. Although these stent grafts have to be customised to the individual patient and are only suitable for certain types of aneurysmal anatomies, they represent the future of thoraco-abdominal aortic aneurysm repair. We review the history of thoraco-abdominal aortic aneurysm repair, the exciting advances in their treatment and discuss our approach to the management of thoraco-abdominal aortic aneurysms in the 21st century.

Novel approach to a type I endoleak following a hybrid repair of an arch aortic aneurysm

Hybrid surgical and endovascular approaches such as open visceral vessel debranching and subsequent endovascular exclusion of thoracic abdominal aortic aneurysms (TAAA) represents a significant development in treatment of TAAAs. As compared to traditional endovascular aneurysm repair, hybrid repairs commonly have a higher rate of endoleak and other endograft-related complications. In this report, we present a 71 year-old man with significant comorbidities including chronic obstructive pulmonary disease, hypertension and prostate cancer. The patient after undergoing debranching of the thoracic arch followed by endograft repair of an arch aneurysm developed a proximal type I and type II endoleak fed by the previously ligated left subclavian artery. Despite coiling of the left subclavian artery and proximal extension of the endograft, a type I endoleak persisted. Several months after the left subclavian artery was coiled, a catheter was advanced through the coils and beyond the site of ligation directly into the aneurysmal sac. Once in the aneurysmal sac, multiple coils were deployed resulting in successful treatment of the type I endoleak. This report highlights the unique challenges in treating proximal descending thoracic aneurysms and represents the first report of the treatment of a type I endoleak with reaccess through a previously coiled vessel for deployment of embolics directly into the aneurysmal sac.

Collective Experience with Hybrid Procedures for Suprarenal and Thoracoabdominal Aneurysms

Not every patient is fit for open thoracoabdominal aortic aneurysm (TAAA) repair, nor is every TAAA or juxtarenal abdominal aortic aneurysm suitable for branched or fenestrated endovascular exclusion. The hybrid procedure consists of debranching of the renal and visceral arteries followed by endovascular exclusion of the aneurysm and might be an alternative in these patients.

Between May 2004 and March 2006, 16 patients were treated with a hybrid procedure. The indications were recurrent suprarenal or thoracoabdominal aneurysms after previous abdominal and/or thoracic aortic surgery ( n = 8), type I to III TAAAs ( n = 3), proximal type I endoleak after endovascular repair ( n = 2), penetrating ulcer of the juxtarenal aorta ( n = 1), visceral patch aneurysm after type IV open repair ( n = 1), and primary suprarenal aneurysm ( n = 1). Eight (50%) of 16 patients were judged to be unfit for open TAAA repair.

The hospital mortality rate was 31% (5 of 16). Four of five deceased patients were unfit for thoracophrenic laparotomy. Two patients died from cardiac complications and three from visceral ischemia. No spinal cord ischemia was detected, and temporary renal failure occurred in four patients (25%). The mean follow-up was 13 months (range 6–28 months). During follow-up, no additional grafts occluded and no patients died.

Hybrid procedures are technically feasible but have substantial mortality (31%), especially in patients unfit for open repair (80%). They might be indicated when urgent TAAA surgery is required or when vascular anatomy is unfavorable for fenestrated endografts in patients with extensive previous open aortic surgery.

Hybrid procedures for thoracoabdominal aortic aneurysms and chronic aortic dissections - a single center experience in 28 patients

OBJECTIVE

We report our 6-year experience with the visceral hybrid procedure for high-risk patients with thoracoabdominal aortic aneurysms (TAAA) and chronic expanding aortic dissections (CEAD).

METHODS

Hybrid procedure includes debranching of the visceral and renal arteries followed by endovascular exclusion of the aneurysm. A series of 28 patients (20 male, mean age 66 years) were treated between January 2001 and July 2007. Sixteen patients had TAAAs type I-III, one type IV, four thoracoabdominal placque ruptures, and seven patients CEAD. Patients were treated for asymptomatic, symptomatic, and ruptured aortic pathologies in 20, and 4 patients, respectively. Two patients had Marfan's syndrome; 61% had previous infrarenal aortic surgery. The infrarenal aorta was the distal landing zone in 70%. In elective cases, simultaneous approach (n = 9, group I) and staged approach (n = 11, group II) were performed. Mean follow-up is 22 months (range 0.1-78).

RESULTS

Primary technical success was achieved in 89%. All stent grafts were implanted in the entire thoracoabdominal aorta. Additionally, three patients had previous complete arch vessel revascularization. Left subclavian artery was intentionally covered in three patients (11%). Thirty-day mortality rate was 14.3% (4/28). One patient had a rupture before the staged endovascular procedure and died. Overall survival rate at 3 years was 70%, in group I 80%, and in group II 60% (P = .234). Type I endoleak rate was 8%. Permanent paraplegia rate was 11%. Three patients required long-term dialysis (11%). Peripheral graft occlusion rate was 11% at 30 days. Gut infarction with consecutive bowel resection occurred in two patients. There was no significant difference between group I and II regarding paraplegia and complications.

CONCLUSIONS

Early results of visceral hybrid repair for high-risk patients with complex and extended TAAAs and CEADs are encouraging in a selected group of high risk patients in whom open repair is hazardous and branched endografts are not yet optional.

Endovascular Repair of Thoracoabdominal Aneurysms

Background— Morbidity and mortality after conventional repair of thoracoabdominal aneurysms remain high. Alternative techniques have been proposed and are the subject of this report.

Methods and Results— Endovascular grafts that have a means of incorporating the visceral vessels into the aortic repair were divided into devices with fenestrations and those with formal branches. Hybrid procedures whereby an extra-anatomic bypass procedure is used to provide inflow to the renal and mesenteric arteries followed by aortic relining with stent grafts were reviewed and tabulated. A description of the techniques and review of the current results are provided. Only 4 series with >10 cases of hybrid procedures have been published. The experience with such a procedure suggests feasibility, but most reports describe a persistently high risk of mortality (up to 25%). Larger series of fenestrated stent grafts to treat juxtarenal aneurysms have been published, and intermediate-term results confirm the safety and efficacy of the procedure. A larger multicenter trial is under way. Other pure endovascular methods have been used to treat thoracoabdominal aneurysms with both reinforced fenestrations and directional branches. Without counting small series (<10 cases), 2 series exist with ≈100 cases that noted perioperative mortality rates between 3% and 6%, without evidence of late ruptures.

Conclusions— Endovascular repair of thoracoabdominal aneurysms is feasible and is associated with relatively low perioperative mortality. Several methods of visceral vessel incorporation have been described. Because of persistently high mortality, hybrid procedures will likely be relegated to nonsurgical and nonendovascular patients with sizable aneurysms. Endografts with branches continue to evolve and will be assessed in the context of clinical trials.