Comparison of supra-arch in situ fenestration and chimney techniques for aortic dissection involving the left subclavian artery

Comparison of total percutaneous in situ microneedle puncture and chimney technique for left subclavian artery fenestration in thoracic endovascular aortic repair for type B aortic dissection

OBJECTIVE

To compare the outcomes of totally percutaneous in situ microneedle puncture for left subclavian artery (LSA) fenestration (ISMF) and chimney technique in type B aortic dissection (TBAD) during thoracic endovascular aortic repair (TEVAR).

MATERIALS AND METHODS

Data on patients who underwent either chimney-TEVAR (n = 89) or ISMF-TEVAR (n = 113) from October 2018 to April 2022 were analyzed retrospectively. The primary outcomes were mortality and major complications at 30 days and during follow-up.

RESULTS

The technical success rate was 84.3% in the chimney group and 93.8% in the ISMF group (p = 0.027). The incidence of immediate endoleakage was significantly higher in the chimney than ISMF group (15.7% vs 6.2%, respectively; p = 0.027). The 1- and 3-year survival rates in the chimney and ISMF groups were 98.9% ± 1.1% vs 98.1% ± 0.9% and 86.5% ± 6.3% vs 92.6% ± 4.1%, respectively (log-rank p = 0.715). The 3-year rate of cumulative freedom from branch occlusion in the chimney and ISMF group was 95.4% ± 2.3% vs 100%, respectively (log-rank p = 0.023).

CONCLUSION

Both ISMF-TEVAR and chimney-TEVAR achieved satisfactory short- and mid-term outcomes for the preservation of the LSA in patients with TBAD. ISMF-TEVAR appears to offer better clinical outcomes with higher patency and lower reintervention rates. However, ISMF-TEVAR had longer operation times with higher procedure expenses.

CLINICAL RELEVANCE STATEMENT

When LSA revascularization is required during TEVAR, in situ, fenestration, and chimney techniques are all safe and effective methods; in situ, fenestration-TEVAR appears to offer better clinical outcomes, but takes longer and is more complicated.

KEY POINTS

LSA revascularization during TEVAR reduces post-operative complication rates. Both in situ ISMF-TEVAR and chimney-TEVAR are safe and effective techniques for the preservation of the LSA during TEVAR. The chimney technique is associated with a higher incidence of endoleakage and branch occlusion, but ISMF-TEVAR is a more complicated and expensive technique.

Midterm Outcomes of Multicenter Castor Single-Branch Stent Graft Use in the Treatment of Thoracic Aortic Diseases

PURPOSE

The aim of this study was to evaluate the midterm efficacy and safety of a single-branch Castor stent graft in the treatment of thoracic aortic disease.

MATERIALS AND METHODS

Clinical data of 106 patients with thoracic aortic disease treated with Castor single-branch stent graft at 3 centers were collected between May 2018 and June 2023. The indicators included technical success, stent-related complication, reintervention, retrograde dissection, endoleak, distal stent graft-induced entry (dSINE), branch patency, and mortality. The outcomes of the Castor stent graft for multibranch reconstruction above the arch was also analyzed.

RESULTS

The technical success was 98.1% (104/106), while the surgical success was 93.4% (99/106). The reintervention was 2.8% (3/106), consisting of a case of retrograde type A dissection, an endoleak, and a dSINE. The retrograde dissection was 1.9% (2/106), while type I endoleak was 1.9% (2/106). The new dSINE was 2.8% (3/106), and the branch patency rate was 100%. The mortality was 1.9% (2/106). The mean follow-up time was 29.1±17.7 months. The 2-year post-surgery cumulative survival rate was 91.0%±3.1%, while the cumulative branch patency rate was 96.2%±2.2%. In addition, the cumulative freedom from stent-related reintervention rate was 93.2%±2.8%. A comparison showed no significant difference in the stent-related complication, branch patency, endoleak, reintervention, and mortality when the proximal end of the Castor stent graft was anchored to zones 1 or 2 of the aorta.

CONCLUSION

Castor single-branch stent graft showed favorable early and midterm outcomes in the treatment of thoracic aortic disease. In addition, it was feasible to combine Castor stent graft with other advanced techniques for multibranch aortic arch reconstruction.

CLINICAL IMPACT

The Castor single-branch stent graft was approval by the Chinese Food and Drug Administration in 2017. However, there were few studies on the mid-term outcomes for thoracic aortic disease after launching, which mainly focused on small single-center retrospective study. In the study, we assessed the mid-term outcomes of Castor stent graft through multi-center cases, Castor stent graft combined with other advanced techniques (such as fenestration and hybrid) for multi-branch reconstruction of aortic arch were also conducted. We found Castor single-branch stent graft showed favorable early and mid-term outcomes in the treatment of thoracic aortic disease. Additionally, it was feasible to combine Castor stent graft with other advanced technique for multi-branch aortic arch reconstruction. As an off-the-shelf branched stent graft with a wide range of models, it could be also used in most emergent situation. The Castor stent graft was expected to become more widely used in the future.

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

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

Comparison of Chimney and Fenestrated Techniques for Supra-Aortic Branch Revascularization During Thoracic Endovascular Aortic Repair: A Systematic Review and Meta-Analysis

PURPOSE

To compare the technical and clinical outcomes of fenestrated thoracic endovascular aortic repair (F-TEVAR) and chimney thoracic endovascular aortic repair (CH-EVAR) of aortic disease.

METHODS

PubMed, Embase and Cochrane databases were systematically searched to identify studies on the management of thoracic aortic pathologies using chimney or fenestrated techniques published between 2000 and 2022. Individual studies provided at least one of the following essential outcomes: technical success, immediate and follow-up type I endoleak, 30-day and aorta-related mortality, cerebral events and supra-aortic branch patency.

RESULTS

24 chimney (1106 patients) and 21 fenestrated technique studies (1040 patients) were included. The scope of the study encompassed various thoracic aortic conditions, such as thoracic aortic dissection, thoracic aortic aneurysm, thoracic aortic ulcer, and other thoracic aortic diseases. Technical success was defined as the handling of the principal ailment affecting the aorta, devoid of any instances of complications. The technical success rates were higher in fenestrated group compared with chimney group (98.0% vs. 95.8% p < 0.001), and the rate of type I endoleak either immediately or during follow-up was higher in the chimney technique group (9.3% vs. 1.3% p < 0.001, 4.0% vs. 0.0% p < 0.001). The chimney technique group had higher 30-day mortality and aorta-related mortality than those in the fenestrated technique group (2.1% vs. 0.3% p < 0.001, 0.4% vs. 0.0% p < 0.001). Morbidity rates of cerebral events and supra-aortic branch patency were same in both groups (2.2% vs. 1.1% p = 0.116, 98.2% vs. 99.4% p = 0.094). The chimney technique group had longer operative time (110.0 min vs. 90.8 min p < 0.001). Two groups had same fluoroscopy time (34.0 min vs. 33.4 min p = 0.614).

CONCLUSIONS

The finding suggest that both the chimney and fenestrated techniques are efficacious in supra-aortic branch reconstruction. However, the fenestrated technique exhibits potential superiority as an interventional strategy, as it demonstrates a lower incidence of type 1 Endoleak, 30-day mortality, and aorta-related death following TEVAR.

Technical details of thoracic endovascular aortic repair with fenestrations for thoracic aortic pathologies involving the aortic arch: A Chinese expert consensus

Thoracic aortic pathologies involving the aortic arch are a great challenge for vascular surgeons. Maintaining the patency of supra-aortic branches while excluding the aortic lesion remains difficult. Thoracic EndoVascular Aortic Repair (TEVAR) with fenestrations provides a feasible and effective approach for this type of disease. The devices needed in the procedure are off-the-shelf, with promising results reported in many medical centers. Up until now, there have been no guidelines focusing exclusively on the details of the TEVAR technique with fenestrations. Experts from China have discussed the technical parts of both in situ fenestrations (needle and laser) and fenestrations in vitro (direction inversion strategy and guidewire-assisted strategy), providing a technical reference to standardize the procedure and improve its results.

Type 1A Endoleak after TEVAR in the Aortic Arch: A Review of the Literature

Aortic arch repair is a challenging intervention. Open surgical repair is still considered the gold standard, but in high-risk patients, it is not always a reasonable option, making endovascular approaches an enticing, when not the only available, alternative for treatment. The strategies more commonly adopted are surgical supra-aortic trunk (SAT) rerouting followed by deployment of a standard thoracic endoprosthesis, chimney techniques, custom-made scalloped, fenestrated, and branched devices, and in situ or physician-modified fenestrations. If we excluded techniques involving SAT rerouting where the arch anatomy is surgically modified in order to make deployment in the aortic arch of a standard thoracic endoprosthesis possible, in the other techniques, one or more SATs are incorporated in the thoracic endoprosthesis. In these cases, no matter what solution is adopted, because of the morphology of the aorta at this level, achieving an ideal sealing is extremely difficult, and endovascular treatments of the arch are burdened by an increased risk of type IA endoleaks. PubMed, EMBASE, and Cochrane Library were searched. We identified 1277 records. After reading titles, abstracts, and full texts, we excluded 1231 records. Exclusion criteria were low-quality evidence, abstracts, case reports, conference presentations, reviews, editorials, and expert opinions. A total of 48 studies were included, for a total of 3114 patients. A type IA endoleak occurred in 248 patients (7.7%) with a mean incidence of 18.8% in chimney procedures, 4.8% and 3%, respectively, in fenestrated and branched devices, and 2.2% in in situ fenestration. We excluded from our analysis scalloped technology that is used when the target vessel originates from a healthy landing zone and represents a different anatomical setting. Type IA endoleaks are a concern with all types of endovascular aortic arch repair, and they can compromise the outcomes of the procedure. The rate of type IA endoleaks appears to be significantly higher in chimney procedures. In order to maximize sealing, whenever possible, endovascular repair of the arch should be achieved with custom-made fenestrated devices. However, chimney configurations are still a valuable solution particularly in the emergency setting, although in such a procedure, to guarantee accurate postoperative management and follow-up, an imaging protocol could be useful.

Physician-Modified Endovascular Grafts for Zone-2 Thoracic Endovascular Aortic Repair

OBJECTIVE

 This study aims to describe our technique and early experience with physician-modified endovascular grafts (PMEGs) for aortic arch diseases in zone 2. We used a total endovascular technique based on a single fenestrated endograft to preserve left subclavian artery (LSA) patency.

METHODS

 From December 2019 to August 2020, six consecutive patients with a variety of thoracic aortic diseases were treated with handmade fenestrated thoracic aortic grafts: four aortic dissections, one penetrating aortic ulcer, and one intramural hematoma. The planning, endograft modification, surgical technique, and follow-up of the patients were described. We evaluated immediate technical success and after 30 days, the LSA patency, Type-1 endoleak, and postoperative complications.

RESULTS

 Thoracic endovascular aortic repair (TEVAR) was performed for zone 2 in all cases. Immediate technical success, defined as successful alignment of the LSA with a covered stent and no Type-1 endoleak, was achieved in all cases. Patients had a 30-day follow-up computed tomography, which demonstrated LSA patency and no Type-I endoleaks. To date, no strokes, left arm ischemia, paraplegia, or conversions to open surgery have been reported; one patient operated for acute Type B dissection died during the early follow-up.

CONCLUSION

 TEVAR for zone 2 with a PMEG to maintain LSA patency achieved technical success and early durability. It is expected that with longer follow-up and a larger number of cases, these results will be confirmed.

Midterm Outcomes of an Adjustable Puncture Device for In Situ Fenestration During Thoracic Endovascular Aortic Repair

OBJECTIVE

To evaluate the midterm outcomes of in situ fenestration (ISF) with an adjustable puncture device for aortic arch branch preservation during thoracic endovascular aortic repair (TEVAR).

METHODS

From October 2016 to April 2019, patients with complicated type B aortic dissection, thoracic aortic aneurysm > 5.5 cm in diameter, or aortic penetrating ulcer with a base > 20 mm or depth > 15 mm, who received TEVAR requiring a proximal sealing beyond zone 3 and underwent ISF using an adjustable puncture device, were included. After the procedure, patients were monitored at one, three, six, and 12 months, and annually thereafter. Peri-operative and follow up data were collected and analysed.

RESULTS

Fifty of 51 patients (98%) received successful ISFs. One, two, or three aortic arch branches were preserved in 44, six, and one patient, respectively. Intra-operatively, eight type Ia endoleaks and one type II endoleak were found on angiography. One patient died of cerebral hernia three days post-procedure from a severe stroke; one patient suffered from transient paraplegia but recovered in two weeks; one patient had a non-disabling stroke. The median follow up was 31 months (22.5 - 36.5 months). At six month follow up, all nine unmanaged endoleaks had disappeared. One new type Ia endoleak was identified in a patient at the one month follow up which resolved spontaneously one year later. All revascularised arteries were patent at the last follow up. No fractures, migrations, or bridging stent kinks were found.

CONCLUSION

In this largest mechanical based ISF study to date, an adjustable puncture device was shown to facilitate the procedure of ISF during endovascular repair of aortic diseases involving the aortic arch, with high success. The midterm outcome demonstrates the efficacy and safety of the device in assisting with preservation of aortic arch branches.

Endovascular In Situ Fenestration Technique of Aortic Arch Pathology: A Systematic Review and Meta-Analysis

BACKGROUND

The aim of this study was to evaluate the safety, applicability and outcomes of the endovascular in situ fenestration (ISF) technique for patients with aortic arch pathologies by performing a systematic review.

METHODS

We conducted a systematic search using the PubMed, Embase, and Cochrane databases to identify English language articles between January 2004 and March 2019 on the management of aortic arch pathologies using an in situ fenestration technique. Two independent observers selected studies for inclusion in the study, assessed the methodological quality of the included studies, and extracted the data. The studies included all investigated the clinical outcomes and postprocedural complications of using ISF techniques.

RESULTS

Seven studies reported on a total of 117 aortic arch pathologies patients. Including 52 dissection patients, 47 aneurysm patients, 18 intramural hematomas and penetrating ulcers patients. Needle fenestration and laser fenestration were performed in 62 and 45 patients respectively, and the rest 10 patients received radiofrequency fenestration. The follow-up period ranged from 1 to 55 months. The pooled technical success rates were 94% (95% confidence interval [CI]: 79-98%). The stroke rate was 6% (95% CI: 3-13%). The 30-day MAE was 11% (95% CI: 6-18%).

CONCLUSION

The results of the study showed that using the in-situ fenestration technique for treating patients with aortic arch pathologies produced encouraging mid-outcomes. Long-term outcomes remain undefined.

Aneurysms and dissections - What is new in the literature of 2019/2020 - a European Society of Vascular Medicine annual review

More than 6,000 publications were found in PubMed concerning aneurysms and dissections, including those Epub ahead of print in 2019, printed in 2020. Among those publications 327 were selected and considered of particular interest.

Endovascular management of chronic post-dissection aneurysms of the aortic arch

This article reviews endovascular management of chronic post-dissection aneurysms of the aortic arch. Therapeutic strategies intended for this complex aortic condition are evolving rapidly to allow the treatment of various hostile aortic anatomy and frail patients. Principles, technical considerations, devices and outcomes of each technique are reviewed and summarized. Hybrid repair offer similar early mortality and stroke rates compared to open conventional surgery. Arch chimney and other parallel graft techniques present poor long term outcome, and should be limited to emergency situations where no other option is available. Fenestrated stent-grafting is subjected to many technical challenges in aortic arch due to difficulties in stent-graft orientation and fenestration positioning. In situ fenestration is an off-label technique that should only be used as an emergency bailout maneuver, considering that temporary coverage of supra aortic trunk vessel and its long-term durability raise concern. Finally, in experienced hands and appropriate anatomic conditions, arch branched graft technology has shown itself to be a safe and effective alternative to open conventional surgery. No randomized controlled trials have yet compared total endovascular aortic arch repair with hybrid techniques and open arch repair. The management of chronic post-dissection aneurysms of the aortic arch is challenging, decision-making and interventions should continue to be performed in high-volume centers with a dedicated aortic team with an expertise in both open and endovascular repairs.

Endovascular treatment for aortic arch pathologies: chimney, on-the-table fenestration, and in-situ fenestration techniques

Background

Revascularization of the supra-aortic major branches in thoracic endovascular aortic repair (TEVAR) is challenging owing to the complex anatomic configuration of aortic arch pathologies. This study aims to evaluate the feasibility, effectiveness, and safety of three major techniques—chimney, fenestrated, and in-situ fenestration—for patients with aortic arch pathologies.

Methods

A retrospective analysis was performed involving 234 patients with aortic arch lesions, who underwent TEVAR with adaptations in technique (chimney, fenestrated, or in-situ fenestration) between January 2016 and December 2017.

Results

One hundred and twenty-six patients underwent the chimney technique (98 single chimneys, 24 double chimneys, and four triple chimneys); one hundred and two patients (102/234) were treated with on-the-table fenestration technique (92 single fenestrations, nine double fenestrations, and one double fenestration plus innominate artery chimney); and the remaining six patients underwent in-situ needle fenestration technique. Overall, indications included aortic dissections (99/234), aortic arch aneurysms (60/234), penetrating aortic ulcers (72/234), and re-interventions (3/234). The technical success rates were 99.6%. There were five cases of early all-cause mortality. The patency rates of overall branches were 99.6%. There were 15 cases with type Ia endoleak—14 in the chimney group (11.1%) and one in the on-the-table fenestration group (1%). Five patients underwent re-interventions. The median follow-up time for all patients was 28 (range, 16–41) months.

Conclusions

Our experience suggests that chimney, on-the-table fenestration, and in-situ needle fenestration techniques are feasible, effective, and safe treatment options for aortic arch pathologies with encouraging mid-term results. Long-term durability concerns require further evaluation.

Hemodynamic consequences of TEVAR with in situ double fenestrations of left carotid artery and left subclavian artery

The aortic major branches after thoracic endovascular aortic repair (TEVAR) could be preserved by in situ fenestration (ISF). This study aims to explore the hemodynamic consequences of ISF-TEVAR with double fenestrations. Two patients with aortic dissection and aneurysm, respectively, were treated by ISF-TEVAR and both the left carotid artery (LCA) and left subclavian artery (LSA) were reconstructed by fenestration technique. The blood was considered a non-Newtonian fluid and the Windkessel model was adopted at the aortic outlets. Simulations were performed in two postoperative models to analyze the effects of the double fenestration stents on the hemodynamics. The postoperative wall pressure of the LCA and LSA is relatively low and the pressure difference between the inner and outer walls of the protruding segment of the LSA stent is found. Acceleration occurs when blood flows around the fenestration stents and the shear-thinning rheological behavior is observed at the aortic arch. Moreover, regions susceptible to thrombosis are identified and the surface exposed to high relative residence time is located at the aortic arch after the LSA stent. The presence of the double fenestration stents has a profound impact on the postoperative hemodynamics, and the aortic arch and rebuilt branches should be closely watched during follow-up.