Triple-barrel graft as a novel strategy to preserve supra-aortic branches in arch-TEVAR procedures: clinical study and systematic review

Endovascular aortic arch repair with chimney technique for pseudoaneurysm

BACKGROUND

Aortic pseudoaneurysm is a life-threatening clinical condition, and thoracic endovascular aortic repair (TEVAR) has been reported to have a relatively satisfactory effect in aortic pathologies. We summarized our single-centre experience using chimney TEVAR for aortic arch pseudoaneurysms with inadequate landing zones.

METHODS

A retrospective study was conducted from October 2015 to August 2020, 32 patients with aortic arch pseudoaneurysms underwent chimney TEVAR to exclude an aortic lesion and reconstruct the supra-aortic branches, including 3 innominate artery, 12 left common carotid arteries and 29 left subclavian arteries. Follow-up computed tomography was suggested before discharge; at 3, 6, 12 months and yearly thereafter.

RESULTS

The median age of 32 patients was 68.0 years (range, 28-81) with the mean max diameter of aneurysm of 47.9 ± 12.0 mm. Forty-four related supra-aortic branches were well preserved, and the technical success rate was 100%. The Type Ia endoleaks occurred in 3 (9%) patients. Two patients were lost to follow-up and 4 patients died during the follow-up period. The mean follow-up times was 46.5 ± 14.3 months. One patient died due to acute myocardial infarction just 10 days after chimney TEVAR and the other 3 patients passed away at 1.5 months, 20 months, and 31 months with non-aortic reasons. The 4.5-year survival estimate was 84.4%. The primary patency rate of the target supra-arch branch vessels was 97.7% (43/44), and no other aorta-related reinterventions and severe complications occurred.

CONCLUSION

For aortic arch pseudoaneurysms with inadequate landing zones for TEVAR, the chimney technique seems to be feasible, with acceptable mid-term outcomes, and it could serve as an alternative minimally invasive approach to extend the landing zone. Slow flow type Ia endoleak could be treated conservatively after chimney TEVAR. Additional experience is needed, and the long-term durability of chimney TEVAR requires further follow-up.

Tratamiento endovascular con técnica de chimenea para patologías del arco aórtico

Introducción. La patología del arco aórtico se ha tratado principalmente con cirugía por vía abierta, pero con una alta morbimortalidad. Las técnicas endovasculares híbridas y las reconstrucciones en “chimenea” son una técnica válida y segura para disminuir el riesgo y la mortalidad. Métodos. Se presentan dos pacientes con patología del arco aórtico y contraindicación de manejo quirúrgico abierto, atendidos en el Servicio de Cirugía Vascular, Hospital Universitario Clínica de San Rafael, Bogotá, D.C., Colombia. Resultados. Se realizaron dos procedimientos endovasculares del arco aórtico para tratar un aneurisma torácico roto y una úlcera aórtica sintomática, con cubrimiento de los troncos supra aórticos con una endoprótesis y canalización de los vasos supra aórticos con prótesis cubiertas y uso de la “técnica de chimenea”, de manera exitosa. Discusión. La patología del arco aórtico es de alta complejidad y se asocia con una morbimortalidad elevada por lo que, en los últimos 20 años se han desarrollado diferentes técnicas utilizando procedimientos percutáneos. Conclusión. La “técnica de chimenea” se puede realizar de una manera mínimamente invasiva en pacientes con patología del arco aórtico, no candidatos para cirugía abierta, con resultados exitosos.

Outcomes of thoracic endovascular aortic repair with chimney technique for aortic arch diseases

Objective

This study aimed to summarize the long-term experience of using the chimney technique in thoracic endovascular aortic repair (TEVAR) for aortic arch diseases.

Methods

From November 2007 to June 2021, a total of 345 consecutive patients (mean age 56 ± 11.3 years, range 28–83, 302 men) with aortic arch pathologies underwent TEVAR combined with chimney technique (cTEVAR). Their medical data and follow-up results were retrospectively reviewed and analyzed.

Results

Among the 345 patients, 278 (80.6%) received single chimneys, 53 (15.4%) received double chimneys, 7 (2%) received triple chimneys, and 7 (2%) underwent cTEVAR accompanied by other techniques (two with extra-anatomical bypass, two with in situ fenestration, and three with physician modified fenestration). A total of 412 chimney stents were used, including 27 in the innominate artery (IA), 113 in the left common carotid artery, 270 in the left subclavian artery, and two in the aberrant right subclavian artery. Early type IA endoleaks were found in 38 (11%) patients, including 12 with the double or triple chimney technique. Early type II endoleak was found in nine (2.6%) patients. Early re-intervention occurred in two patients with double chimney technique, one for chimney stent migration and the other for compression of chimney stent. The 30-day mortality was 1.2% (4 in 345). During a mean follow-up of 42 ± 22 months (range 1–108 months), major stroke occurred in nine (2.6%) patients, chimney occlusion or stenosis occurred in six (1.7%), and retrograde type A aortic dissection occurred in four (1.2%). Fourteen (4.1%) patients received the secondary intervention. The all-cause mortality was 6.7% (23 in 345). Additionally, the total adverse event rate after cTEVAR was 13.9% (48 in 345).

Conclusion

TEVAR with chimney technique provides a minimally invasive alternative with good chimney graft patency and low postoperative mortality during follow-up. However, the double and triple chimney techniques should be used cautiously as they seem to have a higher risk for type IA endoleak and adverse events after the operation.

Outcomes of Great Vessel Debranching to Facilitate Thoracic Endovascular Aortic Repair

OBJECTIVES

With the expanding application of endovascular technology, the need to deploy into zone 0 has been encountered on occasion. This study evaluates the outcomes of great vessel debranching (GVD) as a method of extending the proximal landing zone (PLZ) to facilitate thoracic endovascular aortic repair (TEVAR).

METHODS

A single-center retrospective review of all patients who underwent GVD followed by TEVAR between May 2013 and December 2020 was conducted. The primary outcome was primary patency of all targeted vessels, with all-cause perioperative mortality as a secondary outcome. Kaplan-Meier analysis was used to account for censoring the mortality and primary patency. The extent of hybrid aortic repairs was characterized into type I: GVD + TEVAR without ascending aorta or aortic arch reconstruction; type II: GVD + TEVAR with ascending aorta reconstruction; and type III: GVD + TEVAR with ascending aorta and aortic arch reconstruction with an elephant trunk (surgical or "frozen").

RESULTS

There were 42 patients (23 males [54.8%], mean age of 62.2 ± 11.2 years) who underwent GVD with 122 vessels revascularized (42 innominate, 42 left common carotid [LCCA], and 38 left subclavian [LSA] arteries). The indication for TEVAR was aneurysmal degeneration from aortic dissection in 32 (76.2%) patients, thoracic aneurysm in 9 (21.4%) patients, and perforated aortic ulcer in 1 (2.4%) patient. Median duration between GVD and TEVAR was 82 days. Mean follow-up was 25.7 ± 23.5 months. Type I repair was performed in 4, type II in 16, and type III in 22 patients. Perioperative mortality, stroke, and paraplegia rates were 9.5%, 7.1%, and 2.4%, respectively. Neither the extent of repair (p = 0.80) nor a prior history of aortic repair (p = 0.90) was associated with early mortality. Late deaths (>30 days) occurred in 6 of 38 patients who survived the perioperative period. At 36 months, the survival estimate was 68.6% (95% CI: 45.7% - 83.4%); the overall primary patency of the innominate artery, LCCA, and LSA was 100%, 89.5%, and 94.1%, respectively. The primary assisted patency rate was 100% for all vessels.

CONCLUSIONS

GVD is a safe and effective means of extending the PLZ into zone 0 with outstanding primary patency rates. Further studies are needed to confirm the safety and longer-term durability in these patients.

Aortic arch debranching in hybrid thoracic aortic replacement

OBJECTIVE

To analyze the outcomes of aortic arch debranching in hybrid thoracic aortic replacement.

MATERIAL AND METHODS

There were 107 patients who underwent hybrid thoracic aortic repair with debranching of supra-aortic vessels between 2015 and 2021. Patients underwent total and partial debranching (subtotal debranching and subclavian-carotid anastomosis/bypass). Debranching was performed in patients with type 3 dissection, type B aneurysms, post-traumatic aortic isthmus and arch aneurysms, thoracoabdominal aneurysms type A and DeBakey type 1 dissections.

RESULTS

One patient (0.9%) died from thoracic aorta rupture after retrograde dissection. There was a moderate decrease of blood flow velocity through the left vertebral artery after subtotal debranching without severe hemodynamic disorders. Despite mild surgical trauma, subtotal and especially total debranching are characterized by higher risk of thrombosis of branches with potential fatal outcomes. In young patients requiring subtotal aortic arch debranching, open reconstruction or repair with fenestrated stents is preferred. We recommend a Bavaria type II hybrid procedure for patients with high surgical risk. In our opinion, more physiological hybrid interventions with anatomical arrangement of supra-aortic vessels such as Elephant Trunk and Frozen Elephant Trunk procedures are preferred.

Chimney Graft Technique Combined With Embolization for Treating Ruptured Aortic Arch Lesions

Background: This study aimed to share the experience in applying the chimney graft technique combined with embolization for treating aortic arch rupture under emergency conditions and evaluating early-term results in these patients. Methods: This study retrospectively included patients with ruptured aortic arch lesions who received the chimney graft technique combined with embolization between March 2016 and March 2021. The primary endpoint was a technical success, deemed as successful stent graft deployment to the planned location, patency of the target branch vessel, and absence of significant type I endoleak. The secondary endpoint was clinical success defined with the size of false lumen in follow-up remaining unchanged or decreasing over time, 30-day mortality, complication, and primary patency of chimney graft. Results: This study included 12 patients (age, 61 ± 12 years; male, 83%). Five patients (42%) received single chimney, one patient (8%) received double chimney, and six patients (50%) received triple chimney. Intraoperative type I endoleak occurred in six patients (50%) who underwent endovascular embolization in the primary operation. Post-operative type I endoleak, evaluated by computed tomography angiography examination following the primary operation, occurred in seven patients (58%), including one patient who received endovascular embolization two times. All patients with post-operative type I endoleak were successfully re-treated using coil and Onyx glue within 1 week, and the median length of stay was 22 ± 11 days (range: 7-44 days). Overall technical success was 100%. Eleven patients had completed their follow-up (median, 12 months, range: 1-34 months), and one patient was out of contact. The 30-day mortality was 9% (1/11, post-operative death of a patient with cerebral hemorrhage). No major complications and no chimney compression, migration, occlusion, or stenosis were recorded during follow-up. Seven patients (58%) have ≥6 months of clinical follow-up time with appropriate imaging. In four (57%) of these patients, diameter stabilization was detected, whereas three (43%) experienced significant reduction (≥5 mm). Conclusion: The patients in this study had satisfactory early-term outcomes. The chimney graft technique combined with coil and Onyx glue embolization may be a safe and effective treatment for ruptured aortic arch lesions under emergency conditions.

Thoracic aortic parallel stent-graft behaviour when subjected to radial loading

To manage complex aortic arch disease using minimally invasive techniques, interventionalists have reported the use of multiple stent-graft devices deployed in a parallel configuration. The structural device-device and device-artery interactions arising during aortic arch parallel endografting, also known as chimney thoracic endovascular aortic repair (ch-TEVAR), is not well understood. Through the use of a radial force testing system we sought to characterise both the loading and deformation behaviour of parallel endografts in representative ch-TEVAR configurations. Four commercially available devices (Bentley BeGraft, Gore TAG, Gore Viabahn, and Medtronic Valiant) were subjected to uniform radial load individually, and in six combinations, to quantify loading profiles. Image data collected during testing were analysed to evaluate mechanical deformations in terms of gutters, chimney and main endograft compression, as well as graft infolding. Parallel endografting was found to increase radial loads when compared to standard TEVAR. Chronic outward force during ch-TEVAR was dependent on main endograft manufacturer, with TAG combinations leading to consistently higher loads than Valiant, but independent of chimney graft type. Endograft deformations were dependent on chimney graft type, with Viabahn combinations presenting with lower gutter areas and increased lumen compression than BeGraft. Chimney graft deformations were also influenced by deployment arrangement in the case of double ch-TEVAR. This study emphasizes the significant variability in both radial loads and mechanical deformations between clinically relevant ch-TEVAR configurations.

Long-Term Clinical Outcomes of Thoracic Endovascular Aortic Repair for Arch Aneurysms with the Najuta Thoracic Stent-Graft System

Objective: The treatment for arch aneurysms by endovascular repair is often difficult. This study evaluated the long-term outcomes of thoracic endovascular aortic repair for aortic arch aneurysms treated with the Najuta stent-graft system.

Materials and Methods: From January 2009 to December 2019, 37 patients underwent treatment for aortic aneurysms with the Najuta stent graft system at two institutes, including our hospital. We retrospectively analyzed the short- and long-term clinical outcomes.

Results: Of all 37 cases, the technical success rate was 97.3% (36 of 37). The mean proximal neck length was 20.1±5.3 mm. The postoperative results revealed 10 patients with type Ia endoleaks (27.8%), 6 with stroke (16.7%), and one with paraplegia (2.8%). In the chronic phase, the overall survival rates and the rates of freedom from aorta-related events at 7 years were 71.3% and 50.7%, respectively. Between two groups divided based on the proximal neck diameter of 20 mm, the <20-mm group had significantly higher rates of aorta-related events in terms of freedom from aortic events (P=0.046).

Conclusion: The fenestrated stent graft can be a less invasive option for the treatment of high-risk patients with aortic aneurysms.

Long-Term Outcomes after Thoracic Endovascular Aortic Repair Using Chimney Grafts for Aortic Arch Pathologies: 10 Years of Single-Center Experience

BACKGROUND

This study reports the early- and long-term outcomes of the thoracic endovascular aortic repair using the Chimney-Graft technique (ChTEVAR) for the treatment of aortic arch pathologies.

METHODS

From January 2010 to December 2019, patients who underwent aortic ChTEVAR technique in our institution were included. Early, mid, and long-term outcomes in this group of patients were evaluated. Patient follow-up data were obtained by imaging follow-up that are routinely performed after 3-6 months following initial surgery and then at yearly intervals.

RESULTS

Aortic arch repair with a ChTEVAR was performed in 54 patients. The 30-day mortality was 18.5% (n = 10). All-cause 30-day mortality was higher in the subgroup of patients operated urgently (33% vs. 14%) without a significant difference (P = 0.141). Permanent neurological deficit (PND) was observed in 15% (8/54 patients); stroke in 11% (6/54), and paraplegia 4% (2/54). During follow-up the primary and primary-assisted chimney-graft patency was 96.8% and 97.8%, respectively. The multivariate analysis identified the age >70 years and the aortic diameter as independent risk factors for elevated mortality during the follow-up (P = 0.015 and 0.001, respectively). The PND was an independent predictor for 30-day mortality (P = 0.014, hazard ratio 13.5, 95% confidence interval 1.7-106.6).

CONCLUSIONS

The ChTEVAR has noninferior results to other open and endovascular aortic arch repair methods with an acceptable long-term survival especially in elective procedures.

Various Endoluminal Approaches Available for Treating Pathologies of the Aortic Arch

Open surgical repair of the aortic arch for degenerative aortic disease in an unfit patient is associated with significant morbidity and mortality. Endoluminal techniques have advanced over the last decade. Contemporary endovascular options including a hybrid approach (supra-aortic debranching and aortic stent graft), inner branched endograft, chimney stents, and scallop or fenestrated endografts are being used frequently as an alternative to open surgical arch repair. Understanding of the available endoluminal technology along with careful planning and effective teamwork is required to minimise complications associated with the endoluminal techniques, particularly neurological ones. Custom made techniques are superior to chimney or parallel technology in terms of their complications and durability. Integration of the protective devices such as embolic protection filters into stent design may reduce the risk of poor neurological sequelae. Long-term data are needed to assess the durability of these devices.

Endovascular aortic repairs combined with looping-chimney technique for repairing aortic arch lesions and reconstructing left common carotid artery

Background

The aim of this retrospective study was to evaluate the feasibility and efficacy of thoracic endovascular aortic repairs (TEVAR) combined with looping chimney technique (LCT) for repairing aortic arch lesions and reconstructing left common carotid artery.

Methods

Total of 14 patients (mean age 52.86±14.46 years; range, 27–79; 10 men, 4 women) were included in the study from December 2016 to December 2018. Aortic arch pathologies of all patients with insufficient proximal landing zone (PLZ) were repaired by TEVAR under local anesthesia, before TEVAR, the left common carotid artery (LCCA) was protected by the guiding sheath from the retrograde brachial access, after aortic stent graft deployed, chimney graft was implanted to restore LCCA by LCT if necessary. All patients underwent computed tomography angiograph (CTA) 2 weeks, 3 months, 6 months and 1 year after surgery.

Results

Pathology results of 14 patients included: type B aortic dissection (n=8), penetrating aortic ulcers (n=1), retrograde type A aortic dissection (n=1), thoracic aortic aneurysm (TAA) (n=2), and thoracic aortic pseudoaneurysm (n=2). In all patients, aortic arch lesions were repaired by TEVAR; while LCCA were successfully reconstructed by the LCT. In one case, the innominate artery (IA) was simultaneously reconstructed through the same percutaneous right brachial artery (RBA) access. Coiling eliminated type Ia endoleak in 3 patients, and type II endoleak vanished by plugging left subclavian artery (LSA) in 2 patients. In four patients, the chimney stent (CG) of LCCA was partially compressed and then another bare stent was implanted to restore patency rate. The mean follow-up duration was 9.77±6.64 months (range, 0–24) and no combinations were observed in 13 patients; except in one patient who died of cerebral hemorrhage due to abnormal coagulation function.

Conclusions

TEVAR combined with LCT has shown to be suitable surgical approach for aortic arch lesions. Either covered intentionally or inadvertently, the LCCA could be safely and effectively reconstructed via percutaneous RBA access. Short-term follow-up demonstrated satisfactory morbidity and mortality in high-risk patients; however, longer follow-up is required to assess the effectiveness and durability of this innovative endovascular procedure.

Long-Term Outcome of Chimney Technique Using a Balloon-Expandable Bare-Metal Stent to Preserve Supra-Arch Branches in Type B Aortic Dissection

PURPOSE

This study was performed to investigate the long-term effect of chimney technique using balloon-expandable bare-metal stents (BMSs) to preserve the supra-arch branches in type B aortic dissection (TBAD).

METHODS

Fifty patients with TBAD treated by thoracic endovascular aortic repair with the chimney technique (chTEVAR) using balloon-expandable BMSs from July 2009 to December 2013 were retrospectively assessed. Follow-up computed tomography angiography was performed to assess the postoperative outcomes. The primary end point was a persistent type Ia endoleak (ELIa). The secondary endpoints were chimney stent (CS)-based complications (stenosis, occlusion, fracture, or transposition), all-cause mortality, reintervention, and stroke.

RESULTS

Fifty supra-arch branches (left common carotid artery, n = 11; left subclavian artery, n = 39) were preserved via the chimney technique with 50 balloon-expandable BMSs. The technical success rate was 100%. An immediate ELIa was discovered in 9 (18%) patients. The median survival duration during follow-up was 77.3 months. Five (10%) patients had a persistent ELIa; 3 of these patients had an immediate ELIa. Asymptomatic CS-based complications were found in 3 (6%) patients. The all-cause mortality rate was 8% (4/50); 2 deaths were aortic-related deaths. Five (10%) patients underwent a reintervention. During the estimated 36-month survival period, the survival rate, the rate of freedom from persistent ELIa, and the rate of freedom from reintervention were 93.87%, 89.48%, and 95.56%, respectively.

CONCLUSIONS

The long-term outcomes showed that chTEVAR using balloon-expandable BMSs was safe and feasible for preservation of the supra-arch branches. Evaluation of more patients with a longer follow-up period is needed.

Thoracic endovascular aortic repair in penetrating aortic ulcer combined with isolated left vertebral artery: A case report

RATIONALE

Penetrating aorta ulcer (PAU) with isolated left vertebral artery (ILVA) is a rare condition, accounting for no more than 1% of all kinds of aorta diseases. And traditional treatment was open surgery with total arch replacement by elephant trunk. Here, we report a case of PAU combined with ILVA managed by thoracic endovascular aortic repair (TEVAR) technique.

PATIENT CONCERNS

A 65-year-old male with chronic hypertension and Nicotine abuse underwent intermittent back pain for 2 years and aggravated a bit for 1 week.

DIAGNOSES

Preoperative computed tomography angiogram (CTA) indicated PAU combined with ILVA.

INTERVENTIONS

TEVAR was performed for PAU following with retrograde in situ fenestration and chimney technique for revascularization of ILVA and left subclavian artery (LSA), respectively.

OUTCOMES

The operation was successfully and the patient was discharged from hospital after 1 week of treatment. Postoperatively, the images of CTA illustrated the patency of aorta, ILVA, and LSA without obvious endoleak. Besides, no ischemia attack or other relative syndromes were detected at 6-months follow-up.

LESSONS

This case demonstrates that TEVAR is an alternative to elephant trunk especially for PAU with ILVA. And it also showed the precise exposure of ILVA and necessity to reconstruct ILVA during TEVAR operation in order to reduce the occurrence of ischemia attack.

A Shorter Aortic Arch Sealing Ring (< 10 mm) Distal to the Most Distal Chimney Seems to Be an Additional Important Factor Contributing to a Gutter Endoleak in Aortic Arch TEVAR

BACKGROUND

The aim of the present study was to define the possible anatomical and technical parameter that might predict the occurrence of gutter endoleak or type Ia endoleak (EL Ia) in patients treated with the chimney graft (CG) technique for the brachiocephalic trunk (BCT) and left common carotid artery (LCCA) due to aortic arch pathologies.

METHODS

We reviewed our institutional endovascular aortic database of patients, who between 2010 and 2018 had undergone thoracic endovascular aortic repair (TEVAR) with chimney graft technique (ChTEVAR) as a debranching method of the supraaortic arteries.

RESULTS

ChTEVAR was performed in 45 patients of whom a chimney in both the LCCA and the BCT was used in 32 patients, only in the LCCA in twelve patients, and only in the BCT in one patient. Eight patients (17.8%) had an EL Ia (based on postoperative computed tomography angiography). No late EL Ia was detected during the follow-up period. All patients with a postoperative EL Ia received 2 CGs with one each for the BCT, and LCCA had either no or a sealing ring distal to the most distal chimney of less than 10 mm versus patients with a longer sealing zone (P = 0.043). Patients with an endoleak did not differ from those without endoleak with respect to stent-graft oversizing, the diameter of the proximal and distal landing zones, or the aortic diameter directly proximal to the pathology.

CONCLUSIONS

A sealing ring distal to the most distal chimney of more than 10 mm seems to be associated with a reduced risk of an EL Ia. The relatively few patients and the single-center nature require larger studies to verify the present results.

FEATURES OF DEBRANCHING TECHNIQUE FOR AORTIC DISSECTIONS AND ANEURYSMS IN THORATIC AND THORACO-ABDOMINAL AORTAS

This article describes a hybrid surgical technique for high-risk patients with thoraco-abdominal aortic dissections and aneurysms. The technical aspects of the first stage of surgical treatment - visceral and brachiocephalic debranching are described in detail. 17 surgical interventions for chronic dissection and aneurysm in the thoracic and thoracoabdominal aortas were performed at the Vishnevsky National Medical Research Center of Surgery of Ministry of Health of the Russian Federation in the period from 2014 to 2019. In two cases, we observed postoperative pancreatitis after surgical treatment of the abdominal aorta branches, which we managed using conservative therapy. After open surgery, all patients were discharged in a satisfactory condition. The selected technique made it possible to prepare patients for the following stage of treatment - endografting of the aorta - without developing serious complications.

Antegrade thoracic endovascular aneurysm repair via the ascending aorta

PURPOSE

We performed antegrade thoracic endovascular aneurysm repair via the ascending aorta in selected high-risk patients scheduled for open surgery, in whom an iliofemoral or abdominal aortic approach was not feasible. We present our initial experience with this approach.

METHODS

Of 16 consecutive patients who underwent antegrade endovascular aneurysm repair via the ascending aorta at our institution, 3 had an emergency intervention for rupture and 3 had an urgent intervention for impending rupture or complicated aortic dissection. The procedure was scheduled in 10 patients. The median patient age was 77 years. In 13 patients, one or more concomitant procedures were performed. In 6 patients, vascular access for endovascular aneurysm repair was obtained via a branch of the replacement graft. In 10 patients, direct cannulation of the ascending aorta was carried out using 2 pursestring sutures.

RESULTS

The initial success rate was 100%. Early mortality occurred in 2 (12.5%) patients because of multiple organ failure in one and heart failure in the other. No patient required a second intervention during follow-up. The mean duration of follow-up was 19 months.

CONCLUSION

The antegrade approach is a useful alternative in patients with no access suitable for endovascular aneurysm repair and who are not appropriate candidates for open conventional thoracic aortic surgery. This approach is applicable to selected 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.

Emergency Endovascular Management of a Symptomatic Pseudoaneurysm of the Left Subclavian Artery Ostium Using a Combination of an Abdominal Aortic Stent-Graft Extension Cuff and a Periscope Stent Graft

A pseudoaneurysm located at the subclavian artery ostium is an infrequent but life-threatening pathology that usually requires major thoracic surgery with a high risk of mortality and morbidity. Endovascular therapy applied to the aortic arch branches is a recent alternative technique, which is still in its early stages because dedicated endovascular devices for the aortic arch are lacking. In this article, we present the emergency endovascular management of a symptomatic pseudoaneurysm of the left subclavian artery ostium which was presumably secondary to an atherosclerotic plaque rupture. Endovascular exclusion required a combination of an abdominal aortic stent-graft extension cuff, which was placed via a retroperitoneal iliac access, and a subclavian artery periscope stent graft.

Application of triple-chimney technique using C-TAG and Viabahn or Excluder iliac extension in TEVAR treatment of aortic arch dilation diseases

Background

To report the experience of a single centre regarding the application of the triple-chimney technique using C-TAG with Viabahn or Excluder iliac extension devices for the endovascular management of aortic arch dilation diseases.

Methods

From July 2016 to August 2017, 7 patients (5 men; mean age 56.1±10.8 years) with aortic arch dilation diseases were treated with the triple-chimney technique. All patients were followed up at 1, 3, and 6 months and every 6 months thereafter.

Results

Six innominate arteries were deployed with Excluder iliac extensions and one with a Viabahn cover-stent. All the left common carotid arteries and left subclavian arteries were placed with Viabahn. Reverse chimney technique was applied in four patients. Three (42.0%) type I endoleaks were found on the final angiogram. Two were apparently reduced, and one disappeared after balloon dilation. The mean follow-up time was 15.7 months (9-20 months). All the type I endoleak was found disappeared within 3 months. One patient died of myocardial infarction at 6 months after discharge. No other complications such as stent-graft migration, occlusion, type II endoleak or neurological stroke occurred.

Conclusions

The use of C-TAG coupled with Viabahn or Excluder iliac extension is feasible and effective for the treatment of aortic arch dilatation diseases. However, more patients and longer follow-up time are required to verify its long-term safety and efficacy.

Endovascular management of acute aortic dissection

Acute dissection of the thoracic aorta is a potentially life-threatening condition which requires collaborative treatment from multiple specialties for optimal patient outcomes. Dissections involving the ascending aorta and aortic arch have traditionally been managed entirely by surgery, while dissections beyond the arch vessels have most commonly been relegated to medical management. This algorithm has been undergoing a paradigm shift over the past two decades due to improvements in stent graft technology, better understanding of the hemodynamic interactions of the true and false lumen and their influence on organ and limb perfusion, and improvements in medical management and long term surveillance for dissection-related complications. This manuscript includes a brief discussion of the pathogenesis and etiology of dissection, followed by an in-depth review of the medical and endovascular techniques utilized to treat patients afflicted by this condition.

Two-Vessel Branched Stent Graft for Severely Angulated Aortic Arch Aneurysm in a Jehovah's Witness

Aneurysmal disease involving the origins of supra aortic vessels often requires complex open and/or endovascular repair that is not only associated with significant risk of mortality and morbidity but also often with perioperative blood loss requiring transfusion. We report a successful repair of a large thoracic aortic aneurysm (TAA) involving the aortic arch with a custom-made Bolton Relay 2-vessel branched thoracic aortic endograft in a 42-year-old Jehovah's Witness who would otherwise be very unlikely to survive an open repair. Branched thoracic aortic endografting offers a potentially safe, minimally invasive, and effective alternative for TAA disease involving the supra-aortic arteries, especially in patients who are at high risk of open surgery.

Single-center mid-term experience with chimney-graft technique for the preservation of flow to the supra-aortic branches

Objectives

To investigate the feasibility and the mid-term outcomes of the chimney-graft technique for the revascularization of supra-aortic branches in patients with thoracic aortic pathologies involving the aortic arch.

Methods

A retrospective analysis of a prospectively maintained database between January 2010 and July 2016 was performed. Primary endpoints were 30-day and overall mortality. Secondary endpoints were technical success, target vessel patency, stroke/transitory ischemic attack and type I/III endoleak rate.

Results

A total of 30 patients (80% male, median age 70.0 years) were treated using the chimney-graft technique for the supra-aortic branches. The indication was a degenerative aneurysm in nine patients (32%) and a type B Stanford aortic dissection and a penetrating aortic ulcer in the descending aorta in seven patients (23%), respectively. In six patients (20.0%), the indication was an type Ia endoleak after previous endovascular thoracic repair, whereas a pseudoaneurysm after previous open repair of the descending aorta was the indication in one patient (3%). Twenty-three patients (77%) were treated electively, five (17%) emergently and two (7%) urgently because of free rupture. Technical success was achieved in 90% of patients. The 30-day/in-hospital mortality was 17% (5/30). A retrograde dissection was presented in five patients. Four patients experienced a cerebrovascular event. Eight patients had type Ia endoleak and 10 had type II. During the median follow-up of 16 months (range: 0–56), four further patients died: one in respiratory insufficiency, one due to a ruptured abdominal aortic aneurysm, one in meningitis and the last one for unknown reason. The chimney-graft patency was 100%. According to the Kaplan–Meier curve, the estimated survival at one year was 66 ± 9%.

Conclusions

The chimney-graft technique, despite a technically demanding strategy, is a useful tool as bailout procedure in our armamentarium for high-risk patients, unsuitable for open or hybrid repair.

Aortic Dissection: Novel Surgical Hybrid Procedures

The management of patients with aortic dissection is challenging and its treatment is an area of development and innovation. Conventional surgical techniques are associated with significant risks in terms of mortality and morbidity in such high-risk patients. As a result of cumulative advances in technology, classical surgical techniques have been improved and enhanced by the newer endovascular approaches, leading to novel surgical hybrid procedures. Impressive early results have been seen with frozen elephant techniques, revascularisation of the supra-aortic branches and branched/fenestrated thoracic endovascular aortic repair-alone procedures. This review describes the techniques involved in the latest hybrid procedures for aortic dissection and their outcomes.

Thoracic Endovascular Aortic Repair With Single/Double Chimney Technique for Aortic Arch Pathologies

Purpose: To summarize a single-center experience using the single/double chimney technique in association with thoracic endovascular aortic repairs (TEVAR) for aortic arch pathologies. Methods: From November 2007 to March 2016, 122 patients (mean age 50.4±12.7 years, range 29–80; 92 men) with aortic arch pathologies underwent TEVAR combined with single (n=101) or double (n=21) chimney grafts to reconstruct the supra-aortic branches: 21 innominate arteries, 114 left common carotid arteries, and 8 left subclavian arteries (LSA). Pathologies included type B aortic dissection (n=47), aortic arch dissection (n=49), retrograde type A aortic dissection (n=8), thoracic aortic aneurysm (n=7), penetrating aortic arch ulcer (n=9), and post-TEVAR type I endoleak (n=2). Follow-up examinations included computed tomography at 0.5, 3, 6, and 12 months and yearly thereafter. Results: The aortic stent-grafts were deployed in zone 0 (n=21), zone 1 (n=93), and zone 2 (n=8). One (0.8%) of the 122 patients died at 4 days due to a perforated peptic ulcer. Type Ia endoleaks were found intraoperatively in 13 (10.7%) patients, including 3 with the double chimney technique. Type II endoleaks occurred in 6 (4.9%) patients; 3 were treated with duct occluders in the LSA. Postoperative chimney graft migration occurred in 1 (0.8%) patient with double chimneys; additional stent-grafts were deployed in both chimneys. Median follow-up was 32.3 months, during which 1 (0.8%) patient died after a stroke at 3 months. Chimney stent-graft patency was observed in the remaining 120 patients. Two (1.7%) secondary TEVARs were performed for distal aortic dissection. Nine asymptomatic type Ia endoleaks and 1 type II endoleak persisted in follow-up; a type II endoleak in 1 patient with Marfan syndrome sealed in 52 months. Conclusion: TEVAR with the chimney technique provides a safe, minimally invasive alternative with good chimney graft patency and low postoperative mortality during midterm follow-up. The double chimney technique should be used judiciously owing to its potential complications.

Fenestrated and Branched Aortic Grafts

BACKGROUND

Abdominal and thoracic aortic aneurysms are diagnosed in 40 and 10 to 15 out of 100 000 persons per year, respectively. Fenestrated (fEVAR) and branched (bEVAR) stent grafts have been developed for abdominal juxtarenal and thoracoabdominal aneurysms. We discuss the patency and complication rates of fEVAR and bEVAR procedures and compare them with the outcome of open surgery.

METHODS

This review is based on pertinent publications from 2011 to 2014 that were retrieved by a selective literature search. The clinical outcomes of case series involving a total of more than 1500 patients are presented. The discussion takes account of recommendations contained in the literature and the authors' own experience.

RESULTS

Open surgery and aortic stent grafting have not been compared in any randomized trial to date. We identified 7 clinical series that included a total of 1270 fEVAR patients and 5 with a total of 408 bEVAR patients. The perioperative mortality after fEVAR procedures was 0-4%. Spinal cord ischemia arose in 1% of cases. The stent patency rate in visceral vessels ranged from 93 to 98%. bEVAR procedures were associated with both higher mortality (4-7%) and more common spinal cord ischemia (4-13%). 5-8% of all patients needed dialysis perioperatively, and the stent patency rate in visceral vessels was 94-97%. Preoperative renal insufficiency was a risk factor for peri-interventional death. Impaired renal function after fEVAR/bEVAR procedures was mainly associated with intermittent lower limb ischemia.

CONCLUSION

The results of fEVAR/bEVAR procedures in the last 5 years are similar to those of open surgery. The high postoperative rate of spinal cord ischemia remains a serious problem in the endovascular treatment of thoracoabdominal aortic aneurysms. The decision to implant a stent graft by an endovascular approach or to treat surgically should be made on a case-to-case basis in an interdisciplinary vascular conference.

Chimney Grafts in Aortic Stent Grafting: Hazardous or Useful Technique? Systematic Review of Current Data

BACKGROUND

The chimney graft (CG) technique was introduced to rescue accidentally covered aortic branches during aortic endovascular repair. It extends the sealing zone. There is concern about "gutter" type I endoleak (EL-I) and about the durability of CGs. The aim of the present report was to analyze the rapidly increasing existing data.

METHODS

A search was performed (PRISMA criteria) for all studies of visceral and thoracic/arch chimney grafts. Technical and clinical details and outcome were assessed.

RESULTS

The present review includes 831 patients who underwent EVAR/TEVAR (endovascular aneurysm repair/thoracic endovascular aneurysm repair) with one or more chimney, periscope, or sandwich grafts. For aortic visceral vessels 517 patients received 911 visceral CGs and 314 patients received 364 arch CGs. Most procedures (81% visceral and 69% arch CGs) were elective. Thirty day mortality was 4% for both groups. The rate of early EL-I was 13% (visceral CGs) and 11% (arch CGs). Most EL-I were handled conservatively (observation: 70% for visceral CG and 45% for arch CG). Early CG patency was high (97-99%) and remained high during follow up (median 17 months). Late (after 30 days) EL-I was reported in nine visceral (2%) and 12 arch (4%) CG cases. Few other late complications were reported, but those losing a kidney at the initial repair seemed to have a high risk of requiring permanent hemodialysis.

CONCLUSION

Increasing amounts of data support the benefit of visceral and arch chimney graft techniques. In particular, the low early mortality and complication rates and high long-term patency seem advantageous; however, the majority of cases have been treated electively, and there is a high risk of bias in all studies. Mid- to long-term data suggest few late complications, except in cases where one renal artery was sacrificed. The CG technique is valuable for complex urgent patients and needs further documentation for other patient groups.

TEVAR: Endovascular Repair of the Thoracic Aorta

The development of thoracic endovascular aortic repair (TEVAR) has allowed a minimally invasive approach for management of an array of thoracic aortic pathologies. Initially developed specifically for exclusion of thoracic aortic aneurysms, TEVAR is now used as an alternative to open surgery for a variety of disease pathologies due to the lower morbidity of this approach. Advances in endograft technology continue to broaden the applications of this technique.

["Debranching" -- a new surgical option for the aortic arch and thoracoabdominal aorta hybrid interventions]

INTRODUCTION

Endovascular techniques in vascular surgery are frequently applied to treat aortic diseases. These minimally invasive procedures changed aortic interventions remarkably. We have to be familiar with new terminology and methods.

METHOD

New and old surgical procedures gained new role in preparation of endograft implantations. Transforming anatomy of aortic branches - "debranching" - is aimed to create a sufficient fixation of the endografts at safe "landing zones".

CONCLUSIONS

Knowing the option of hybrid procedures is a fundamental requirement for the vascular surgeon. Equally important is to know the biomechanical characteristics of the available endografts, the possible complications during and after implantation and the treatment options. We have to be aware of the limitations of these new methods and the role of traditional open surgery in the new era. Our intention in this paper is to summarize methods of debranching.

Chimney technique for aortic arch pathologies: an 11-year single-center experience

PURPOSE

To report our single-center experience with the chimney technique for aortic arch pathologies and the mid- to long-term results in these patients.

METHODS

From June 2002 to May 2013, 26 patients (18 men; mean age 71.2 years, 53-86) underwent thoracic endovascular aortic repair (TEVAR) combined with chimney technique. Indications for treatment were: a proximal landing zone <15 mm long distal to the left subclavian artery (LSA), thoracic aortic aneurysm (n=13), complicated type B aortic dissection (n=10), type I endoleak after previous TEVAR (n=2), and penetrating aortic ulcer (n=1). Treatment was performed in the emergency setting in 7 cases. The 28 chimney stent-grafts (double chimneys in 2 patients) were deployed in the innominate artery (n=7), left common carotid artery (n=10), and LSA (n=11). All patients underwent computed tomography before discharge, at 1, 6, and 12 months, and yearly thereafter.

RESULTS

Technical success was 100%. One (3.8%) perioperative death was due to a cerebral hemorrhage. No major stroke was registered, but 3 (11.5%) minor strokes occurred (all resolved). Paraparesis developed in 2 (7.7%) patients. Median follow-up was 36.8 months (range 1-131), during which an additional 4 (15.4%) patients died, but only 1 death was aneurysm-related. Chimney graft patency was 89.3% (25/28); an asymptomatic fracture was found in a patent chimney stent-graft at the 18-month follow-up. The type I endoleak rate was 23% (n=6); 3 endoleaks associated with aneurysm sac enlargement were treated.

CONCLUSION

The chimney technique for aortic arch pathologies is safe and feasible and may be an option in patients considered at high risk for surgery or who are ineligible for conventional TEVAR, especially in the emergency setting. Concern persists regarding type I endoleak, and long-term follow-up remains mandatory.