Aortic arch aneurysms: treatment with extraanatomical bypass and endovascular stent-grafting

Endoluminal Repair of a Thoracic Arch Aneurysm Using a Scallop-Edged Stent-Graft

Purpose:

To report a new technique of endoluminal thoracic aortic arch aneurysm repair using a scalloped stent-graft.

Case Report:

A 79-year-old man presented with a 7.5-cm thoracic aneurysm involving the inner curve of the aortic arch. Endoluminal repair was performed with a scalloped stent-graft that allowed perfusion of the brachiocephalic (innominate) artery. Preliminary extra-anatomical left common carotid and subclavian artery bypass grafting had been performed to allow coverage of the origins of these vessels.

Conclusions:

The use of fenestrated endoluminal grafts in the aortic arch can be achieved safely and may increase the treatment options for the high-risk patient.

Development of a Branched Stent-Graft for Endovascular Repair of Aortic Arch Aneurysms

Purpose:

To develop a branched stent-graft for endovascular repair of aortic arch aneurysm.

Methods:

Four different prototypes of a branched aortic stent-graft were inserted into a rubber model of the human aortic arch under fluoroscopic guidance. Each prototype was tested, modified, and tested again through a series of 4 iterations. The first 3 prototypes had multiple short side branches, as docking sites for extensions into the branches of the aortic arch. The last iteration had only 1 short branch for an extension into the distal aorta and 1 long branch for direct perfusion of the innominate artery.

Results:

With every re-design, the prototype aortic stent-graft became shorter, and its insertion site moved to a more proximally located arch artery. Stent-graft insertion, orientation, and extension also became quicker and easier with each change in device design. However, the only system to perform reliably was the last, which was subsequently used to treat a large, symptomatic pseudoaneurysm of the aortic arch in a high-risk patient.

Conclusions:

None of our multibranched systems was simple, safe, or durable enough for insertion into the aortic arch; only an iteration that had a short branch for an extension into the distal aorta and a long branch for direct perfusion of the innominate artery could be deployed without difficulty or delay.

Aortic Arch and Descending Thoracic Aortic Aneurysms: Experience with Stent Grafting for Second-Stage “Elephant Trunk” Repair

Reconstruction of aortic arch and descending thoracic aortic aneurysms (TAAs) is technically challenging and associated with significant morbidity and mortality. We report our experience with extensive TAAs using a two-stage “elephant trunk” repair, with the second stage completed using an endovascular stent graft (ESG). Over 6 years, 111 patients underwent ESG treatment of TAAs at Mount Sinai Medical Center. Twelve of these patients were referred for ESG placement for the second stage of elephant trunk reconstruction because comorbidities placed them at high risk of open surgical repair. Our database was analyzed for technical and clinical success and perioperative complications. The mean follow-up was 11.8 months (range 1–64 months). Twelve patients (five women and seven men) with a mean age of 69 ± 10 years underwent repair of their distal aortic arch and descending TAAs. These aneurysms included nine atherosclerotic aneurysms, one pseudoaneurysm, and two penetrating atherosclerotic ulcers. Three patients were symptomatic. Stent graft repair was technically successful in 91.7% or 11 of 12 patients. Excessive aortic arch tortuosity resulted in failure to deploy a stent graft in one patient. An antegrade approach through the open elephant trunk was used in two patients with severe iliac occlusive disease. Endoleaks (type 2) were identified in two patients with no aneurysm expansion; however, a 14 mm expansion over 1 year occurred in a patient with no identifiable endoleak. One early mortality occurred in a patient with a ruptured 6 cm infrarenal AAA after successful exclusion of the 8 cm TAA. Second-stage elephant trunk reconstruction of an extensive TAA using an ESG is effective in the short term. Its long-term durability remains to be determined.

Total arch repair using supra-aortic debranching technique with banding of the ascending aorta for endovascular stent graft fixation

Endovascular stenting requires a satisfactory landing zone that guarantees fixation and sealing of the proximal part of the endograft. We report total arch repair using supra-aortic debranching technique with banding of the ascending aorta for endovascular graft fixation. An 85-year-old man presented with hoarseness of voice. A fusiform aneurysm with a maximum transverse diameter of 62 mm on the aortic arch was identified by computed tomographic angiography. Supra-aortic arch debranching of the 3 neck vessels using a trifurcated graft and coronary arterial bypass grafting were performed while closely monitoring the regional cerebral oxygen saturation. The ascending aorta was dilated to 41 mm; we successfully reduced this to a mean outer diameter of 36 mm by banding the aorta using an expanded polytetrafluoroethylene surgical membrane. The endovascular procedure was performed 17 days after surgical intervention. The patient was extubated immediately after endovascular stent placement and spent 1 day in intensive care with no signs of transient or permanent neurologic events. A postoperative computed tomographic scan did not reveal any evidence of endoleak. The banding of the ascending aorta for endovascular graft fixation could facilitate endovascular aortic arch repair and provide an alternative treatment for high-risk patients.

Usage of external shunt in hybrid approach for aortic arch aneurysm to restore cerebral oxygenation

A hybrid approach, combining open and endovascular procedures, may be a less invasive substitute to correct aortic arch pathologies in high-risk patients. We describe an 82-year-old male patient with an atherosclerotic aortic arch aneurysm, which was treated with proximal transposition of all arch branches and endovascular aortic arch repair. During the left common carotid artery reconstruction, oxygen saturation level of the left cerebral hemisphere decreased lower than the safety limit. To re-establish brain perfusion, we installed an external shunt from the right common femoral artery to the left common carotid artery. The oxygen saturation was restored to an acceptably safe level, and the patient tolerated the procedure without any signs of postoperative ischemic stroke.

Hybrid endovascular repair in aortic arch pathologies: a retrospective study

The aortic arch presents specific challenges to endovascular repair. Hybrid repair is increasingly evolving as an alternative option for selected patients, and promising initial results have been reported. The aim of this study was to introduce our experiences and evaluate mid-term results of supra aortic transpositions for extended endovascular repair of aortic arch pathologies. From December 2002 to January 2008, 25 patients with thoracic aortic aneurysms and dissections involving the aortic arch were treated with hybrid endovascular treatment in our center. Of the 25 cases, 14 were atherosclerotic thoracic aortic aneurysms and 11 were thoracic aortic dissection. The hybrid repair method included total-arch transpositions (15 cases) or hemi-arch transpositions (10 cases), and endovascular procedures. All hybrid endovascular procedures were completed successfully. Three early residual type-I endoleaks and one type-II endoleak were observed. Stroke occurred in three patients (8%) during the in-hospital stage. The perioperative mortality rate was 4%; one patients died post-operatively from catheter related complications. The average follow-up period was 15 ± 5.8 months (range, 1–41 months). The overall crude survival rate at 15 months was 92% (23/25). During follow-up, new late endoleaks and stent-raft related complications were not observed. One case (4%) developed a unilateral lower limb deficit at 17 days and was readmitted to hospital. In conclusion, the results are encouraging for endovascular aortic arch repair in combination with supra-aortic transposition in high risk cases. Aortic endografting offers good mid-term results. Mid-term results of the hybrid approach in elderly patients with aortic arch pathologies are satisfying.

Hybrid procedures as a combined endovascular and open approach for pararenal and thoracoabdominal aortic pathologies

OBJECTIVES

to report our experience with hybrid vascular procedures in patients with pararenal and thoracoabdominal aortic pathologies.

METHODS

68 patients were treated for thoracoabdominal aortic pathologies between October 1999 and February 2004; 19 patients (16 men; mean age 68, range 40-79) with high risk for open thoracoabdominal repair were considered to be candidates for combined endovascular and open repair. Aortic pathologies included five thoracoabdominal Crawford I aneurysms, one postdissection expanding aneurysm, three symptomatic plaque ruptures (Crawford IV), five combined thoracic descending and infrarenal aneurysms with a healthy visceral segment, three juxtarenal or para-anastomotic aneurysms, and two patients with simultaneous open aortic arch replacement and a rendezvous maneuver for thoracic endografting. Commercially available endografts were implanted with standardized endovascular techniques after revascularization of visceral and renal arteries.

RESULTS

Technical success was 95%. One patient developed a proximal type I endoleak after chronic expanding type B dissection and currently is waiting conversion. Nine patients underwent elective, five emergency and five urgent (within 24 h) repair. 17 operations were performed simultaneously, and 2 as a staged procedure. Postoperative complications include two retroperitoneal hemorrhages, and one patient required long-term ventilation with preexisting subglottic tracheal stenosis. Thirty-day mortality was 17% (one multiple organ failure, one secondary rupture after open aortic arch repair, one myocardial infarction). Paraplegia or acute renal failure were not observed. Total survival rate was to 83% with a mean follow-up of 30 months.

CONCLUSIONS

Midterm results of combined endovascular and open procedures in the thoracoabdominal aorta are encouraging in selected high risk patients. Staged interventions may reduce morbidity.

Hybrid Technique for Total Arch Repair: Aortic Neck Reshaping for Endovascular-Graft Fixation

PURPOSE

Endovascular repairs of the aortic arch aneurysms require correct placement and an appropriate landing zone for fixation, which are not present in the majority of cases.

DESCRIPTION

We report a less invasive approach in 4 patients presenting an aortic arch aneurysm. We performed a hybrid procedure that is a combination of different techniques: a mid-sternotomy is performed, followed by transposition of the supra-aortic vessels, and neck reshaping with a proximal banding of the aortic arch. In particular, we banded the aorta to facilitate and optimize the endovascular fixation of the graft, reducing postoperative type-1 endoleaks.

EVALUATION

The four procedures were uneventful with 1-day intensive care unit recovery. The postoperative and the 1-year follow-up CT scan did not reveal any endoleaks.

CONCLUSIONS

Hybrid technique, combined with banding of proximal aortic arch and endovascular grafting are an alternative technique to the conventional open aortic repair. A polyester cloth banding of the ascending and proximal aortic arch allow the neck reshaping of the aorta optimizing the fixation of the endovascular stent graft.

Great Vessel Management for Endovascular Exclusion of Aortic Arch Aneurysms and Dissections

OBJECTIVES

To evaluate a recent approach for the endovascular repair of thoracic aortic aneurysms and dissections involving the aortic arch in high risk patients (HRP).

METHODS

Amongst 102 thoracic aortic aneurysms and dissections, we treated 25 patients for aortic arch endovascular exclusion after transposition of the great vessels, of which 14 (56%) had thoracic aortic arch aneurysms and 11 type A and B chronic aortic dissections. Total transpositions were done in 15 cases (60%) and hemi-arch transpositions in 10. We then used Talent, Excluder and Zenith endografts in 12, seven and six cases, respectively.

RESULTS

Surgical transpositions were complicated by one minor stroke, which worsened to a major stroke (4%) after endovascular exclusion. After endovascular exclusions, two patients (8%) died from catheterization related complications. One patient had a delayed minor stroke (4%). The successful exclusion rate was 92%. During follow-up (15+/-5.8 months), one patient (4%) developed unilateral limb palsy, successfully treated by CSF drainage. The late exclusion rate remained 92%. No stent-related complications were seen.

CONCLUSIONS

Transposition of supra-aortic vessels allows the endovascular exclusion of the aortic arch in HRP. Aortic endografting after surgical transposition proved to be feasible and offers good mid-term results. Specialized surgical centers with both endovascular and surgical expertise are required to treat these patients.

Great Vessel Transposition for Antegrade Delivery of the TAG Endoprosthesis in the Proximal Aortic Arch

PURPOSE

To report a technique for antegrade delivery of the TAG stent-graft during repair of lesions in the proximal aortic arch.

TECHNIQUE

Via an 8-cm median sternotomy, a bifurcated graft, usually 14 or 16 mm in diameter, is anastomosed to the ascending aorta with 4-0 Prolene suture; a 10-mm straight graft is cut obliquely and anastomosed to the heel of the bifurcated graft for delivery of the endograft antegrade across the aortic arch. The great vessels in turn are clamped, transected at the arch, and sutured to the bypass graft. A 9-F sheath is secured in the conduit, and a 250-cm angled hydrophilic guidewire is passed to the desired iliac artery and exteriorized through the femoral sheath. The conduit is clamped, and the TAG's delivery sheath is substituted for the 9-F sheath. A marker is placed on the conduit to assure that the stent-graft is deployed just beyond the limb origins of the bifurcated graft. The conduit is introduced across the aortic arch, followed by the endograft, which is positioned at the marker as the sheath is withdrawn into the conduit. After completion angiography, the delivery sheath is removed, and the conduit is transected and oversewn. Heparinization is reversed, and the incision is closed, with one mediastinal drainage tube in place.

CONCLUSIONS

This technique allows precise delivery of the endoluminal graft at the proximal aortic arch, thus avoiding problems with retrograde delivery.

An experimental study of a new pull-through technique for aortic arch aneurysm in a porcine model

A new pull-through technique for placement of the aortic arch stent-graft was developed. Self-expandable curved stents (Matsui-Kitamura stents) were used on 4 pigs. With use of the endoscopic system, the sheath insertion was performed at the ascending aorta. By this pull-through method from the ascending aorta to the femoral artery, the stent was deployed into the aortic arch. All stents were successfully deployed into the correct position, and they fitted into the curvature of the aortic arch wall. By this method, stent-grafting for aortic arch aneurysm is expected to be performed with more accuracy and safety.

The proximal landing zone in endovascular repair of the thoracic aorta

In this study we evaluated the relationship between the site of the proximal landing zone during endovascular repair of thoracic aortic pathology and treatment outcomes. We reviewed all cases of endovascular repair of thoracic aortic lesions at our institution in the past 42 months. Thirty-seven Talent thoracic endografts were used to treat 20 thoracic aneurysms, 8 intramural hematomas, 6 aortic dissections, and 3 post-traumatic aneurysms. The proximal edge of the covered endograft was situated proximal to the left common carotid artery (zone 1) in 3 patients, between the left common carotid and subclavian arteries (zone 2) in 4 patients, <2 cm distal to the left subclavian artery (zone 3) in 9 patients, and >2 cm distal to the left subclavian (zone 4) in 21 patients. Five patients had extraanatomic bypass to revascularize one or more covered aortic branches. For zones 1, 2, 3, and 4 the endoleak rates were 100%, 0%, 11%, and 0%, respectively; the secondary procedure rates were 33%, 0%, 11%, and 5% respectively; and the treatment failure rates were 67%, 0%, 11%, and 0%, respectively (p < 0.05, for endoleak rates, using Fisher's exact test to compare zone 1 to zones 2, 3, and 4 individually, and as a group). All three endovascular failures were due to proximal type 1 endoleaks. In conclusion, despite the use of great-vessel ligation and extraanatomic bypass to extend the proximal landing zone into the aortic arch, we have been unable to reliably exclude thoracic aortic pathology through use of endografts when the proximal landing zone is proximal to the left common carotid artery.