The Initial Experience on Branched and Fenestrated Endografts in the Aortic Arch. A Systematic Review

Total aortic arch repair with double-fenestrated physician-modified endografts, at least 3-year follow-up

OBJECTIVE

This study aims to report the efficacy and safety of double-fenestrated physician-modified endovascular grafts (PMEGs) for total aortic arch repair with at least 3 years of follow-up.

METHODS

All consecutive patients with a pathological aortic arch who underwent aortic arch repair combined with a homemade double-fenestrated stent graft from 2017 to 2020 were reviewed.

RESULTS

74 patients were treated for pathological arch conditions with a double-fenestrated PMEG. Of these, 81% were male, the mean age was 69.9 years, and 59% were classified as American Society of Anesthesiology 3 or 4. Thirty-five percent were treated for a postdissection aneurysm, 36% for a degenerative aneurysm, and 14% for acute type B dissection. Fifteen percent had supra-aortic trunk dissection. Fenestration on the subclavian artery was performed in 96%; if not, a carotid-subclavian bypass was carried out. Technical success was 100%. The proximal landing zone is consistently in zone 0. Early outcomes revealed a 3% occurrence of type 1 endoleak, which was successfully treated by prompt reintervention. One retrograde dissection occurred, and one patient died from hemorrhage on an iliac conduit. A 5% stroke rate was reported. During long-term follow-up (mean time 40.7 months), one type 1 endoleak appeared and was successfully treated; no type 2 or type 3 endoleak requiring intervention occurred. No stent fractures or migrations were reported. Four percent of patients required reintervention, but no surgical conversion to open surgical repair was needed on the aortic arch. No patient died from a cause related to the main procedure.

CONCLUSIONS

Total aortic arch repair with double-fenestrated PMEGs is associated with acceptable early and midterm major morbidity and mortality. It is suitable for the main aortic pathologies. Moreover, it is easily available for emergency situations.

Current techniques of repair of aortic arch pathologies and the role of the aortic team

The treatment of aortic arch pathologies is becoming progressively more complex and multidisciplinary. Despite progresses in open surgical techniques, the high rate of surgical morbidity and mortality, especially in frail and elderly patients, has led to the development of alternative treatment options to conventional open surgery such as hybrid and endovascular procedures. Our purpose is to summarize the advantages and disadvantages of the different approaches and investigate the role of a dedicated aortic team in the choice of the most appropriate treatment for each patient.

Anatomical Feasibility of the "Canaud Technique" for Physician-Modified Thoracic Endovascular Grafts for the Treatment of Aortic Arch Disease

PURPOSE

Thoracic endovascular aortic repair (TEVAR), originally conceived for deployment distal to the left subclavian artery (LSA), has been recently extended to more proximal landing zones. Among total endovascular solutions, the "Canaud technique" for Physician-Modified Thoracic Endovascular Grafts (C-PMEGs) has gained acceptance with good early results. The aim of this study is to report the proportion of patients with zone 0, 1, and 2 aortic arch lesions that could theoretically be treated with a C-PMEG.

MATERIALS AND METHODS

Computed tomography angiography (CTA) of all consecutive patient candidates to open, hybrid, or endovascular arch repair from January 2009 to July 2023 at our Institution were analyzed. The assessment of feasibility of C-PEMG was conducted following previously extensively described anatomical criteria.

RESULTS

During the study period, 209 consecutive patients were candidates for an open, hybrid, or endovascular aortic arch repair. Of them, 164 patients had a preoperative CTA scan eligible for analysis. One hundred twenty-six patients were male (76.8 %), with a mean age of 67 ± 10.8 years. Ninety-four patients (57.3%) were affected by atherosclerotic aneurysms, 48 post-dissecting aneurysms (29.3%) and 22 penetrating aortic ulcers (PAUs) (13.4%). Twenty patients (12.2%) were suitable for double-fenestrated C-PMEG, and 34 patients (20.7%) for single-fenestrated C-PMEG, totaling 32.9% of the entire cohort. The combination of supra-aortic trunks (SAT) bypass or the use of covered stent in IA or left common carotid artery (LCCA) as adjunctive maneuvers, would extend the C-PMEGs feasibility to 69 patients (42.1%). The use of an iliac graft conduit in 3 (1.8%) patients with inadequate ileo-femoral accesses would increase the C-PMEG suitability to 72 patients (43.9%). The main reason for exclusion was excessive ascending aortic diameter in 78 patients (47.6%).

CONCLUSIONS

The use of C-PMEG was shown to be theoretically feasible in a percentage of patients ranging from 32.9 to 43.9% affected by aortic arch aneurysms, dissections, and PAU. The main reason for exclusion was the dimension of the ascending aorta. The C-PMEG technique is a viable option in aortic arch lesions endovascular treatment. An off-the-shelf device with similar characteristics could also be used in emergency, avoiding the limitations of physician modifications (such as time for back-table procedure, sterility, off-label use).

CLINICAL IMPACT

Thoracic endovascular aortic repair (TEVAR) has been extended to more proximal landing zones for the treatment of aortic arch aneurysm, dissections, penetrating aortic ulcers. Among total endovascular solutions, the "Canaud technique" for Physician-Modified Thoracic Endovascular Grafts (C-PMEGs) has gained acceptance with good early results. The anatomical feasibility in 164 consecutive patients was 69 patients (42.1%), with the combination of supra-aortic trunks (SAT) bypass or the use of covered stent in IA or left common carotid artery (LCCA) as adjunctive maneuvers, showing that the C-PMEG technique is a viable option in aortic arch lesions endovascular treatment.

Effects of Long Term Fatigue Cycling on In Situ Fenestrations of Polyethylene Terephthalate and Expanded Polytetrafluorethylene Thoracic Aortic Stent grafts: An Experimental Study

OBJECTIVE

In this study, the long term durability of fenestrations after in situ fenestration (ISF) of five commercial thoracic aortic stent grafts was evaluated in an in vitro experiment after a simulated 10 year period.

METHODS

Five different thoracic aortic stent grafts (Relay, Valiant, Hercules, TAG, and Ankura, with a diameter of 34 mm) received both needle and laser ISF in vitro. A Viabahn (11 × 50 mm) was released in each fenestration as a bridging stent graft. Long term fatigue tests (simulating 10 years) of each of the fenestrated stent grafts were then conducted in a flow fatigue test system. The area, shape, margin, and the long and short axis of all the fenestrations were evaluated with light microscopy before and after the fatigue test. The leakage from the fenestration junction before and after the long term fatigue was also measured.

RESULTS

The experimental results showed no obvious difference between needle and laser fenestrations. The long axes of all the fenestrations remained unchanged, while the short axes increased after the fatigue test, which was significant in Relay, Valiant, and Hercules polyethylene terephthalate stent grafts. The shape scores of fenestrations improved after the fatigue test in Valiant and Hercules, remained unchanged in Relay and Ankura, and worsened in the TAG. After the fatigue cycling, the average leakage from the fenestration junction decreased in all the stent grafts, and the Ankura had the maximum decline rate.

CONCLUSION

The ISF technique was durable over a simulated 10 year period. The fenestrations were positively remodelled to be more circular, and the leakage from the junction decreased after long term fatigue testing.

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.

Outcomes of Fenestrated and Branched Endografts for Partial and Total Endovascular Repair of the Aortic Arch - A Systematic Review and Meta-Analysis

OBJECTIVE

Fenestrated and branched thoracic endovascular aortic repair (F/B-TEVAR) of the aortic arch is a viable approach in patients unsuitable for open repair. The aim was to summarise the published results of manufactured F/B-TEVAR devices for partial and total repair of the aortic arch, and to compare fenestrated with branched configurations.

DATA SOURCES

PubMed, Scopus and The Cochrane Library were searched for articles (2018 - 2021) about patients with elective, urgent, or emergency aortic requiring a proximal landing zone in the aortic arch (zone 0 - 1 - 2) and treated by F/B-TEVAR.

REVIEW METHODS

The systematic review and meta-analysis were performed according to the PRISMA guidelines. Open repair, supra-aortic trunk (SAT) debranching + standard TEVAR, and in situ physician modified and parallel grafts were excluded. Primary outcomes were technical success and 30 day mortality rate. Secondary outcomes were 30 day major adverse events, and overall survival and procedure related endpoints during follow up.

RESULTS

Of 458 articles screened, 18 articles involving 571 patients were selected. Indications for intervention were chronic dissections (50.1%), degenerative aneurysms (39.6%), penetrating aortic ulcers (7.4%), and pseudoaneurysms (2%). F-TEVAR, B-TEVAR, and F+B-TEVAR were used in 38.4%, 54.1%, and 7.5% of patients, respectively. Overall, technical success was 95.9% (95% confidence interval [CI] 0.93 - 0.97; I2 = 0%; p for heterogeneity (Het) = .77) and the 30 day mortality rate was 6.7% (95% CI 0.05 - 0.09; I2 = 0%; p Het = .66). No statistical differences were found comparing fenestrated with branched endografts, except for a higher rate of type I - III endoleaks in F-TEVAR (9.8% vs. 2.6%; p = .034). The overall survival rate and freedom from aortic related death at the one year follow up ranged between 82 - 96.4% and 94 - 94.7%, respectively. Thirteen and five studies were considered at moderate and high risk of bias, respectively.

CONCLUSION

F/B-TEVAR for the treatment of the aortic arch, according to experience in dedicated centres, now enjoys a satisfactory level of technical success together with a progressively reduced early mortality rate. There are several limitations, and further studies are needed to reach clearer conclusions.

Hybrid Treatment of Complex Diseases of the Aortic Arch and Descending Thoracic Aorta by Frozen Elephant Trunk Technique

The surgical management of acute and chronic complex diseases involving the aortic arch and the descending thoracic aorta remains challenging. Hybrid procedures associating total open arch replacement and stent-grafting of the proximal descending aorta were developed to allow a potential single-stage treatment, promote remodeling of the downstream aorta, and facilitate a potential second-stage thoracic endovascular aortic repair by providing an ideal landing zone. While these approaches initially used various homemade combinations of available conventional prostheses and stent-grafts, the so-called frozen elephant trunk technique emerged with the development of several custom-made hybrid prostheses. The aim of this study was to review the contemporary outcomes of this technique in the management of complex aortic diseases, with a special focus on procedural planning, organ protection and monitoring, refinements in surgical techniques, and long-term follow-up.

Safety and Efficacy of Inner Branched Stent-Graft in the Treatment of Aortic Arch Disease: A Systematic Review

OBJECTIVE

To provide a descriptive overview on the contemporary outcomes of thoracic endovascular arch repair with inner branched endoprosthesis (bTEVAR) for the treatment of aortic arch pathologies.

METHODS

A comprehensive literature search was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Pre-defined search terms were used to interrogate PubMed and OVID Medline databases from January 1999 to July 2022. Patient characteristics, indication for treatment, procedural data, mortality rates, postoperative complications, and reintervention rate during follow-up were evaluated.

RESULTS

Nineteen articles were included, encompassing a total of 618 patients who received bTEVAR, most of which were double-branched (63.9%, n=395). The main indication for treatment was aneurysm secondary to chronic aortic dissection (38.8%, n=240/618) with a mean maximum diameter of 58.3±11.4 mm. Pooled mean technical success rate was 97.4±4.4% (95% confidence interval [CI]=95.1%-99.5%); 2 and 3 patients required conversion to chimney technique and open repair, respectively. Among the pooled rates of early complications, postoperative stroke was the highest (10.5%; 95% CI=6.8%-14.3%). Thirty-day and in-hospital mortality rate was 5.5% (95% CI=2.6%-9.7%). Forty patients (6.5%; 95% CI=2.5%-9.5%) required early reintervention. During a mean follow-up of 20.7±13.5 months, the mortality rate was 18.2% (n=108/593; 95% CI=8.6%-20.6%) where 12 (11.1%) were aortic-related. Pooled late reintervention rate was 9.6% (95% CI=4.8%-14.3%). Comparison of demographics and outcomes found no significant difference between single and double bTEVAR.

CONCLUSION

Branched thoracic endovascular aortic repair is a promising approach for aortic arch pathologies with a high technical success rate despite a steep learning curve. However, contemporary outcomes reflect that postoperative stroke remains the predominant concern. Further experience and long-term follow-up are required to sufficiently elucidate the safety and durability of bTEVAR in the management of aortic pathologies for high-risk patients.

CLINICAL IMPACT

This systematic review summarized the contemporary outcomes of thoracic endovascular aortic repair with different inner branched stent-grafts for the management of aortic arch pathologies. Pooled results from nineteen studies with 618 patients demonstrated a high technical success rate and an acceptable mortality rate. However, postoperative stroke remains the major concern. Long-term follow-up is needed to evaluate its durability.

A technical review of bail-out procedures to place Najuta stent-graft into the ascending aorta

BACKGROUND

The Najuta stent-graft (Kawasumi Laboratories Inc., Tokyo, Japan) is usually easily advanced to the correct deployment position in the ascending aorta thanks to the pre-curved delivery J-sheath with all fenestrations automatically oriented towards the supra-aortic vessels. Aortic arch anatomy and delivery system stiffness could however represent limitations for proper endograft advancement, especially when the aortic arch bends sharply. The aim of this technical note is to report a series of bail-out procedures that could be useful to overcome the difficulties encountered during the Najuta stent-graft advancement up to the ascending aorta.

MAIN BODY

The insertion, positioning and deployment of a Najuta stent-graft requires a through-and-through guidewire technique using a .035″ 400 cm hydrophilic nitinol guidewire (Radifocus™ Guidewire M Non-Vascular, Terumo Corporation, Tokyo, Japan) with right brachial and both femoral accesses. When standard maneuver to put the endograft tip into the aortic arch, some bail-out procedures can be applied to obtain proper positioning. Five techniques are described into the text: positioning of a coaxial extra-stiff guidewire; positioning of a long introducer sheath down to the aortic root from the right brachial access; inflation of a balloon inside the ostia of the supra-aortic vessels; inflation of a balloon inside the aortic arch (coaxial to the device); and transapical access technique. This is a troubleshooting guide for allowing physicians to overcome various difficulties with the Najuta endograft as well as for other similar devices.

SHORT CONCLUSION

Technical issues in advancing the delivery system of Najuta stent-graft could occur. Therefore, the rescue procedures described in this technical note could be useful to guarantee the correct positioning and deployment of the stent-graft.

Analysis of Postoperative Remodeling Characteristics after Modular Inner Branched Stent-Graft Treatment of Aortic Arch Pathologies Using Computational Fluid Dynamics

The modular inner branched stent-graft (MIBSG), a novel interventional therapy, has demonstrated good effects in the endovascular treatment of aortic arch pathologies, especially those involving the supra-aortic branches. Nevertheless, the long-term efficacy of the MIBSG and in-depth quantitative evaluation of postoperative outcomes remain to be examined. Moreover, the regularity of postoperative vascular remodeling induced by MIBSG implantation has yet to be explored. To address these questions, we constructed four models (normal, preoperative, 1 week postoperative, and 6 months postoperative) based on a single patient case to perform computational fluid dynamics simulations. The morphological and hemodynamic characteristics, including the velocity profile, flow rate distribution, and hemodynamic parameter distribution (wall shear stress and its derivative parameters), were investigated. After MIBSG implantation, the morphology of the supra-aortic branches changed significantly, and the branch point moved forward to the proximal ascending aorta. Moreover, the curvature radius of the aortic arch axis continued to change. These changes in morphology altered the characteristics of the flow field and wall shear stress distribution. As a result, the local forces exerted on the vessel wall by the blood led to vessel remodeling. This study provides insight into the vascular remodeling process after MIBSG implantation, which occurs as a result of the interplay between vascular morphological characteristics and blood flow characteristics.

Outcomes of thoracic endovascular aortic repair with fenestrated surgeon-modified stent-graft for type B aortic dissections involving the aortic arch

Objectives

This retrospective analysis aimed to evaluate the early and midterm outcomes of thoracic endovascular aortic repair (TEVAR) with fenestrated surgeon-modified stent-graft (f-SMSG) for type B aortic dissections (TBAD) involving the aortic arch.

Methods

From March 2016 to April 2021, 47 consecutive patients were treated using TEVAR with f-SMSG. All patients were diagnosed with TBAD involving the aortic arch.

Results

In total, 47 patients with TBAD involving the aortic arch were treated with f-SMSGs. There were 21 zone 1 and 26 zone 2 TEVAR, and 65 arteries were revascularized successfully with fenestrations. Technical success was achieved in 46 patients (97.88%). The 30-day estimated survival (± SE) and reintervention was 93.6 ± 1.0% (95% Confidence Interval [CI], 92.6-94.6%) and 91.5 ± 1.2% (95% CI, 90.3-92.7%), respectively. During a median follow-up of 51 months (range, 16-71 months), 1 patient died of rupture of aortic dissection (AD) and 3 patients died of non-aortic-related reasons. Reintervention was performed for four patients, including two patients of type IA entry flow and two patients of type IB entry flow. No occlusion of the supra-aortic trunk was observed. The estimated survival and reintervention (± SE) at 4 years was 88.7 ± 1.4% (95% CI, 87.3-90.1%) and 84.8 ± 1.5% (95% CI, 83.3-86.3%), respectively.

Conclusion

Thoracic endovascular aortic repair with f-SMSG is an alternative treatment option for TBAD involving the aortic arch in high-volume centers.

Protocol for Guo's aortIc Arch recoNstrucTion: a prospective, multicentre and single-arm study to evaluate the safety and efficacy of the WeFlow-Arch modular inner branch stent-graft system for aortic arch lesions (GIANT study)

INTRODUCTION

Endovascular repair of the entire aortic arch provides treatment opportunities for patients with aortic arch lesions who are intolerant to open surgery. However, the complex anatomical configuration, high-speed blood flow and long access from the femoral artery increase the difficulty of endovascular aortic arch repair. On the basis of our earlier studies, a new modular inner branch stent-graft system was developed specifically for lesions located in the aortic arch and part of the ascending aorta. This study aims to evaluate the safety and efficacy of the novel modular branch stent-graft system in patients with aortic arch lesions who are unsuitable for open aortic arch replacement.

METHODS AND ANALYSIS

This prospective, multicentre, single-arm, clinical trial will enrol 80 patients with aortic arch lesions requiring intervention, namely, true aortic arch aneurysms, pseudo-aortic arch aneurysms and penetrating ulcers involving the aortic arch. Clinical information and CT angiography (CTA) images will be collected and analysed to investigate the safety and efficacy of the novel modular branch stent-graft system. Patients will be followed up for 5 years. The primary outcome will be all-cause mortality and severe stroke within 12 months after the procedure. In addition, this trial will evaluate mid-term to long-term clinical and imaging outcomes through the annual clinical and CTA follow-up for 2-5 years postoperatively.

ETHICS AND DISSEMINATION

We have registered the study on a registry website (https://clinicaltrials.gov/ct2/home). The study findings will be disseminated through peer-reviewed journals, physician newsletters, conferences and the mass media.

TRIAL REGISTRATION NUMBER

NCT04765592.

A review: Single and multi-branch devices for the treatment of aortic arch pathologies with proximal sealing in Ishimaru Zone 0

Recently published experience has shown that endovascular management of the aortic arch, including sealing in the proximal zones, can be a viable option for patients considered unfit for conventional open repair. Endograft designs vary and include single or multibranch devices, with or without the addition of surgical debranching. Initial reports show that both techniques can be performed with high technical success and acceptable perioperative morbidity and mortality rates in high volume centers. Single branch devices, available off-the-shelf, may provide a treatment option for emergent presentations where patients cannot wait for the design and manufacture of a customized endograft. Double or triple branched endografts are now increasingly implanted in high-volume aortic centers. The purpose of this review is to describe the single and multibranched endovascular devices currently available for aortic arch repair, their associated published outcomes, and to discuss their relative advantages and disadvantages.

Use of a Steerable Sheath for Completely Femoral Access in Branched Endovascular Aortic Repair Compared to Upper Extremity Access

PURPOSE

To compare bridging stent graft (BSG) implantation in downward oriented branches in branched endovascular aortic repair (bEVAR), using a commercially available steerable sheath from an exclusively femoral access (TFA) with traditional upper extremity access (UEA).

METHODS

In a retrospective cohort study, 7 patients with 19 branches in the TFA cohort received BSG insertion using the Medtronic Heli FX steerable sheath from a femoral access, and 10 patients with 32 branches in the UEA cohort from a brachial approach. Technical success, total intervention time, fluoroscopy time, branch cannulation time, and complication rate were recorded.

RESULTS

Technical success was 19/19 branches in the TFA and 31/32 in the UEA cohort. The mean branch cannulation time was considerably shorter in the TFA group (17 vs. 29 min, p = 0.003), and total intervention time tended to be shorter (169 vs. 217 min, p = 0.176).

CONCLUSION

Using a commercially available steerable sheath allowed successful cannulation of all branches in this cohort and was associated with significantly shorter branch cannulation times. Potentially, this technique can lower the stroke and brachial puncture site complication risk as well as reduce total intervention time and radiation dose.

LEVEL OF EVIDENCE

2b, retrospective cohort study.