Branched Stent Grafts Research Articles

Multicenter global early feasibility study to evaluate total endovascular arch repair using three-vessel inner branch stent-grafts for aneurysms and dissections

ObjectiveWe evaluated the outcomes of total endovascular aortic arch repair using three-vessel inner branch stent-grafts for aneurysms and chronic dissections. MethodsWe reviewed the clinical data and outcomes of consecutive patients treated by total endovascular aortic arch repair at eight academic centers using three-vessel inner branch stent-grafts (William Cook Europe, Bjaeverskov, Denmark) from 2016 to 2019. All patients received three-vessel designs with two antegrade and one retrograde inner branch, which was used to incorporate the innominate, left common carotid, and left subclavian arteries. The antegrade inner branches were accessed via a carotid or an upper extremity approach. A preloaded catheter was used for access to the retrograde left subclavian artery branch via a transfemoral approach. The endpoints were technical success, mortality, major adverse events, any stroke (minor or major) or transient ischemia attack, secondary interventions, target vessel patency, target vessel instability, aneurysm-related mortality, and patient survival. ResultsA total of 39 patients (31 men [79%]; mean age, 70 ± 7 years) had undergone treatment of 14 degenerative (36%) and 25 chronic (64%) postdissection arch aneurysms. The clinical characteristics included American Society of Anesthesiologists class ≥III in 28 patients (95%) and previous median sternotomy for ascending aortic repair in 28 patients (72%). The technical success rate was 100%. Two patients had died in-hospital or within 30 days (5%), and two patients had experienced a stroke (one minor). The combined mortality and any stroke rate was 8% (n = 3). Major adverse events occurred in 10 patients (26%), including respiratory failure in 4 (10%) and estimated blood loss >1 L, myocardial infarction, and acute kidney injury in 2 patients each (5%). The median follow-up was 3.2 months (interquartile range, 1-14 months). Of the 39 patients, 12 (31%) required secondary interventions to treat vascular access complications in 5, endoleak in 6 (three type II, one type Ic, one type Ia/Ib, one type IIIa), and target vessel stenosis in 1 patient. At 1 year, the primary and secondary patency rates and freedom from target vessel instability were 95% ± 5%, 100%, and 91% ± 5%, respectively. Freedom from aortic-related mortality and patient survival was 94% ± 4% and 90% ± 6%, respectively. ConclusionsThe findings from the present multicenter global experience have demonstrated the technical feasibility and safety of total endovascular aortic arch repair for aneurysms and chronic dissections using three-vessel inner branch stent-grafts. The mortality and stroke rates compare favorably with those after open surgical repair in a higher risk group of patients. However, the rate of secondary interventions was high (31%), emphasizing need for greater experience and longer follow-up.

Perioperative Outcome of Fenestrated and Branched Stent Grafting after Previous Open or Endovascular Abdominal Aortic Repair

To compare the perioperative outcome of patients treated with elective or urgent fenestrated and branched stent grafting (fbEVAR) for pararenal (pAAA) and thoracoabdominal aortic aneurysm (TAAA) after previous open with previous endovascular abdominal aortic repair. Single center retrospective analysis of all patients undergoing fbEVAR after previous open (post-open fbEVAR group) or endovascular abdominal aortic repair (post-endo fbEVAR group) between January 2015 and December 2017. Primary outcomes were technical success and in-hospital all-cause mortality. We identified 42 patients undergoing fbEVAR after previous open or endovascular abdominal aortic repair during this period. Twenty-one patients (post-open fbEVAR group) had previous open abdominal aortic repair, 13 with a bifurcated and 8 with a tube graft. Of these, 2 patients presented with pAAA and 19 with TAAA. Twenty-one patients (post-endo fbEVAR group) had previous EVAR. Thirteen patients presented with pAAA, 3 of them with additional type Ia endoleak, 2 with stent-graft migration and 2 with previously failed fEVAR. Eight presented with TAAA. Median interval between previous repair and fbEVAR was 84 months (IQR 60-156) for the post-open fbEVAR group and 72 months (IQR 36-96) for the post-endo fbEVAR group (P = 0.746). Eighteen patients (86%) had branched stent grafting in the post-open versus 11 (52%) in the post-endo group (P < 0.01). In 2 patients in the post-open group, 3 renal arteries were not catheterized due to severe ostial stenosis, resulting in technical success of 91% in the post-open and 100% in the post-endo fbEVAR group. Four patients (19%) in the post-open fbEVAR group died in hospital, 2 due to cerebral hemorrhage and 2 due to pneumonia, and none in the post-endo fbEVAR group (P = 0.101). There were 5 nonstent-graft-related reinterventions, 2 (10%) in the post-open fbEVAR group and 3 (14%) in the post-endo fbEVAR group (P = 0.844). After 12 months there were 4 events in the post-endo fbEVAR group: one renal artery stent occluded, one renal artery stent required relining because of disconnection and 2 type II endoleaks were embolized with coils. There were no reinterventions in the post-open fbEVAR group during 12 months. Fenestrated and branched repair after previous open or endovascular abdominal aortic repair appears safe with high technical success rate. There is no difference in the technical success and in-hospital all-cause mortality rates between fbEVAR after previous open or endovascular abdominal aortic repair.

Endovascular Repair of Aortic Dissection Involving the Left Subclavian Artery by Castor Stent Graft: A Multicentre Prospective Trial

The left subclavian artery (LSA) origin can be intentionally covered by stent grafts, to provide adequate proximal landing zones during thoracic endovascular repair for Stanford type B aortic dissections (TBADs). To preserve the LSA, a novel single branched stent graft, named “Castor” was designed and a clinical trial conducted to investigate its suitability. From April 2013 to March 2015, 73 patients with TBAD were treated by Castor stent grafts at 11 Chinese tertiary hospitals as part of a single arm prospective clinical trial. There were 50 acute (<2 weeks [68.5%]) and 23 chronic aortic dissections (>2 weeks [31.5%]). The technical success rate was 97% (n = 71/73). The two failures were caused by occlusion of the branch section of the stent graft. There were four intra-operative endoleaks (two type Ia, two type B from the LSA). The endoleak rate was 5% (n = 4/73). There was one in hospital death and no major complications. The median follow up time was 61 months (range 48–72 months). The mortality was 5% (n = 4/73) within one year and 7% within six years (n = 5/73). Two deaths were of unknown cause and three were not related to the aorta. Two new entry tears were found on the proximal or distal edge of the stent graft and were retreated endovascularly. Six occlusions of the branch section of the Castor stent graft were found, and the follow up patency rate of the branch section was 93% (n = 63/68). Two intra-operative endoleaks were left during follow up and eventually disappeared according to the latest computed tomography angiograms. For patients with TBADs needing anchoring proximal to the origin of LSA, the Castor single branched stent graft may provide an easily manipulated, safe, and effective endovascular treatment.

Pre-fenestration endovascular repair of aortic diseases in patients with zone 2 segment: A single-center experience

The present study aims to analyze the outcomes of three cases of pre-fenestration and branch stent-graft endovascular repair of aortic disease with zone 2 aortic lesions. From August 2017 to June 2018, three patients with zone 2 aortic lesions underwent thoracic endovascular repair with innominate artery, left common carotid artery, and left subclavian artery recannulation using pre-fenestration and branched stent-grafts to preserve the patency of the aortic arch branches. The technical success rate was 100%. One patient had a proximal type I endoleak with no need for additional treatment. The overall mortality was 0%. All branches were patent. The follow-up period lasted for 2-15 months, with one patient lost to follow-up. There were no conversions to open surgical repair, aortic rupture, paraplegia, or retrograde type A aortic dissection. The use of a pre-fenestration and branch stent-graft for the thoracic endovascular repair of zone 2 aortic lesions is a feasible and effective method for aortic arch branch revascularization. The risk of this surgical procedure is high, requiring significant expertise. The procedure should be conducted only in experienced centers. Durability concerns should be assessed in future studies with long-term follow-up.

Endovascular Repair of Aortic Dissection Involving the Left Subclavian Artery by Castor Stent Graft: A Multicentre Prospective Trial

The left subclavian artery (LSA) origin can be intentionally covered by stent grafts, to provide adequate proximal landing zones during thoracic endovascular repair for Stanford type B aortic dissections (TBADs). To preserve the LSA, a novel single branched stent graft, named "Castor" was designed and a clinical trial conducted to investigate its suitability. From April 2013 to March 2015, 73 patients with TBAD were treated by Castor stent grafts at 11 Chinese tertiary hospitals as part of a single arm prospective clinical trial. There were 50 acute (<2 weeks [68.5%]) and 23 chronic aortic dissections (>2 weeks [31.5%]). The technical success rate was 97% (n=71/73). The two failures were caused by occlusion of the branch section of the stent graft. There were four intra-operative endoleaks (two type Ia, two type B from the LSA). The endoleak rate was 5% (n=4/73). There was one in hospital death and no major complications. The median follow up time was 61 months (range 48-72 months). The mortality was 5% (n=4/73) within one year and 7% within six years (n=5/73). Two deaths were of unknown cause and three were not related to the aorta. Two new entry tears were found on the proximal or distal edge of the stent graft and were retreated endovascularly. Six occlusions of the branch section of the Castor stent graft were found, and the follow up patency rate of the branch section was 93% (n=63/68). Two intra-operative endoleaks were left during follow up and eventually disappeared according to the latest computed tomography angiograms. For patients with TBADs needing anchoring proximal to the origin of LSA, the Castor single branched stent graft may provide an easily manipulated, safe, and effective endovascular treatment.

Anatomical feasibility of a new off-the-shelf inner branch stent graft (E-nside) for endovascular treatment of thoraco-abdominal aneurysms.

The aim of this study was to evaluate the proportion of thoraco-abdominal aortic aneurysms (TAAAs) that could theoretically be treated with the JOTEC® E-nside® Thoracoabdominal Branch Endoprosthesis off-the-shelf multibranched endograft. Preoperative computed tomography scans of patients with atherosclerotic TAAA treated between 2007 and 2019 were reviewed, and the anatomical feasibility of the E-nside graft was verified by a retrospective study (clinicaltrials.gov: NCT03959670) based on the investigational manufacturer instructions for use. The anatomical factors determining overall feasibility were divided into vascular access (AC) feasibility, aortic (AO) feasibility and visceral vessels (VV) feasibility. Two hundred sixty-eight patients with thoraco-abdominal aneurysms were analysed: the overall treatment feasibility was 43%. AC feasibility was 78%, AO feasibility 60% and VV feasibility 79%. An iliac diameter <8.5 mm excluded 21% of the patients. Aortic feasibility was limited by infrarenal aortic diameter (16%) and size of aortic lumen at the level of visceral vessels (14%). Visceral vessels feasibility was mainly limited by inadequate number (8%) or diameter (12%) of target vessels. Height and orientation of target vessels were adequate in 97% of the cases. Overall feasibility was negatively influenced by female gender (Odds ratio: 3.89; 95% confidence interval 2.03-7.44; P < 0.001): the limiting factors in this subgroup being iliac diameter, infrarenal aortic diameter and visceral vessels diameter. The E-nside off-the-shelf stent graft can be theoretically employed in almost half of the cases from an all-comers cohort of patients with TAAA. Improvement of device profile and creation of a dedicated infrarenal component are warranted to increase overall feasibility. Female gender significantly affects the overall feasibility. NCT03959670.

Improved stability of steerable sheath access by femoro-femoral crossover wire in branched stent graft repair of complex thoraco-abdominal aortic aneurysms.

PurposeThe purpose of this study was to describe a technique to catheterize antegrade branches of a branched aortic endograft by using a steerable sheath stabilized by a through-and-through wire via a femoral access.TechniqueAfter implantation of a branched endovascular graft, a steerable 8.5 F sheath is advanced from the femoral access. After placing the sheath proximal to the branches, a 0.014″ through-and-through wire is established to the contralateral femoral access which is held under slight traction after the curved tip of the sheath is brought into the 180° position. Then catheterization, wire exchange and deployment of the bridging stent is done in standard fashion.ConclusionThe use of a through-and-through wire with a steerable sheath for retrograde femoral access adds stability and precision to this technique. It has the potential to reduce the risk of preoperative stroke in complex aortic endovascular repair by avoiding upper extremity access.

Invited commentary

Any stent graft intended for use in the aortic arch has to accommodate variation in the shape, size, position, and orientation of the ascending thoracic aorta, the descending thoracic aorta, and the supra-aortic trunks. In theory, each variable adds an entire dimension to a complex matrix of possible stent graft designs. In practice, it is often possible to mix and match relatively simple modular components during in situ stent graft assembly to achieve a form of intraoperative customization. This modular approach has proved to be successful in the thoracoabdominal aorta, in which (for more than a decade) a single “off-the-shelf” branched stent graft (t-Branch; Cook Medical, Bloomington, Ind) has been combined with a variety of branches, proximal extensions, and distal extensions in elective and urgent circumstances.

Multicenter Global Early Feasibility Study to Evaluate Total Endovascular Arch Repair Using Three-vessel Inner Branch Stent-grafts for Aneurysms and Dissections

To evaluate the outcomes of endovascular repair using three-vessel inner branch aortic arch stent-grafts for aneurysms and chronic dissections. We reviewed the clinical data and outcomes of consecutive patients treated by total endovascular aortic arch repair at eight academic centers using three-vessel inner branch stent grafts (William Cook Europe, Bjaeverskov, Denmark) between 2016 and 2019. All patients received patient-specific stent designs with two antegrade and one retrograde inner branch, which was used to incorporate the innominate, left common carotid, and left subclavian arteries. The antegrade inner branches were accessed via axillary or carotid artery access. A preloaded catheter was used for access to the retrograde left subclavian artery branch via femoral approach (Fig). End points were technical success, mortality, major adverse events, any stroke (minor or major) or transient ischemia attack, secondary interventions, target vessel patency, target vessel instability, aneurysm-related mortality and patient survival. There were 39 patients (31 male patients [79%], mean age 70 ± 7 years) treated for 14 (36%) degenerative and 25 (64%) chronic postdissection arch aneurysms. Clinical characteristics included American Society of Anesthesiologists classification of >3 in 37 patients (95%) and prior median sternotomy for ascending aortic repair in 33 patients (85%). Technical success rate was 100%. There were two in-hospital or 30-day deaths (5%) and two strokes (one minor). Combined mortality/any stroke rate was 8% (n = 3). Major adverse events occurred in 10 patients (26%), including respiratory failure in 4 patients (10%) and estimated blood loss of >1 L, myocardial infarction and acute kidney injury in two patients each (5%). Mean follow-up was 8 ± 10 months. Twelve patients (31%) required secondary interventions to treat vascular access complications in five patients, endoleak in six patients (three type II, one type IC, one type IB, one type IIIA) and target vessel stenosis in one patient. At 1 year, primary and secondary patency rates and freedom from target vessel instability were 95% ± 5%,100%, and 92% ± 5%, respectively. Freedom from aortic-related mortality and patient survival were 94% ± 4% and 90% ± 6%, respectively. This multicenter global experience demonstrates the technical feasibility and safety of total endovascular aortic arch repair for aneurysms and chronic dissections using three-vessel inner branch stent grafts. Mortality and stroke rates compare favorably to reported outcomes of total open surgical arch replacement, particularly among higher risk patients who had prior median sternotomies and ascending aortic repairs. A limitation remains the high rate of secondary reinterventions (31%), emphasizing need for larger experience and longer follow-up.

Early and midterm outcomes of in situ laser fenestration during thoracic endovascular aortic repair for acute and subacute aortic arch diseases and analysis of its complications

ObjectiveAn analysis was conducted of early and midterm outcomes of a large series of patients treated with in situ laser fenestration (ISLF) during thoracic endovascular aortic repair (TEVAR) of acute and subacute complex aortic arch diseases, such as Stanford type A aortic dissection (TAAD), type B aortic dissection (TBAD) requiring proximal sealing at zone 2 or more proximal, thoracic aortic aneurysm or pseudoaneurysm, and penetrating aortic ulcer. We present the perioperative and follow-up outcomes and discuss the rate of complications. MethodsThis is a retrospective review of prospectively collected data from January 2017 to March 2019 of patients treated with TEVAR and ISLF of aortic arch branches at a large tertiary academic institution in an urban city in China. Preoperative, intraoperative, and follow-up clinical and radiographic data are analyzed and discussed. ResultsA total of 148 patients presented with symptomatic and acute or subacute TAAD, TBAD, thoracic aortic aneurysm, or penetrating aortic ulcer for a total of 183 arch vessels. There were 105 men and 43 women, 21 to 79 years of age (mean, 54.9 ± 12.9 years). Time from symptom onset to time of surgery was an average of 7 ± 3 days. Survivor follow-up duration ranged from 5 to 24 months (mean, 15 ± 5 months). Single-vessel fenestration was carried out in 124 cases, two-vessel fenestration in 13 cases, and three-vessel fenestration in 11 cases. There were four cases with technical failure to laser fenestration, with a technical success rate of 97.3%. Postoperatively, there were seven cases of endoleak (4.7%; one type IB distal from the left subclavian artery branch stent graft, three type IIIC at the fenestration site, and three type II), three retrograde dissections (2.0%), and five strokes (3.4%); death occurred in three patients with 30-day mortality of 2.9%, and two deaths occurred during follow-up for 3.4% mortality at an average 15 months of follow-up. There was no branch stent graft occlusion or spinal ischemia postoperatively or during follow-up. The distribution of arch diseases varied significantly according to the number of vessels that were laser fenestrated; TAAD was more likely to receive multivessel laser fenestrations, and TBAD was more likely to receive single-vessel fenestration (P < .001). The rate of complications was distributed differently between the three ISLF groups, with more complications occurring in multivessel fenestrations. However, a statistical weakening was observed when frequency of complications between the three groups was stratified by type of arch disease. The complication rate varied significantly between the different arch diseases, higher in TAAD than in TBAD (P = .008). ConclusionsISLF during TEVAR for treatment of acute and subacute complex aortic arch diseases in the proximal aortic arch is safe and effective on the basis of these early to midterm follow-up data of a large cohort. However, care should be taken in intervening on TAAD using TEVAR with adjunctive multivessel laser fenestration. Continued investigation of TEVAR and adjunctive ISLF is needed to elucidate the long-term outcomes of this minimally invasive treatment for complex aortic arch disease in an urgent setting.

Technical Feasibility of Arch Branched Endograft Repair in Type A Aortic Dissection with Prior Ascending Aortic Replacement

Introduction - Ascending aortic replacement is a common emergency procedure for treatment of acute type A dissection. Secondary open or endovascular intervention for residual arch pathologies is however difficult due to adhesions, short prosthetic grafts, and distorted anatomy. Aortic arch branched stent graft has emerged as a potential solution for these patients. The aim of this study is to evaluate the technical feasibility of two current aortic arch branch stent grafts in patients who had prior ascending aortic replacement. Methods - All patients who had a prosthetic ascending aortic replacement for acute type A dissection in a single institution between January 2013 and December 2017 were included. Contrast CT images on follow up were analyzed on a 3D workstation. Morphologic parameters were measured individually including: (i) Ascending aorta: diameter, greater and lesser curvature length from the coronary origin, angulation of residual ascending aorta and prosthetic graft. (ii) aortic arch: width and height of the arch, tortuosity index. (iii) supra-aortic branches: diameter, separation, sealing length, dissection, and take-off clock positions. Each patient’s CT scan was individually evaluated for anatomical suitability for the Zenith arch branched device (Cook Medical) and Relay double-branch device (Bolton Medical) according to set selection criteria. Adverse anatomical factors were further identified including prosthetic aortic valve replacement, insufficient proximal landing length, incompatible landing zone diameter, severe angulation of prosthetic ascending aorta, hostile arch branches sealing zone, and insufficient innominate artery (IA) sealing zone. Results - CT images from 56 subjects (45 males, mean age 57±10.8 years) were reviewed. 45 patients had ascending aortic replacement alone, 7 had a Bentall procedure, and 4 underwent David procedure. Based on our evaluation results, 23 patients (41.1%) were good candidates for an endovascular arch branched device. It should be mentioned that two patients were suitable for Relay double-branch device but not for Zenith branched device because the former displays more accommodating for larger proximal landing diameter (<43mm) than the latter (<38mm). Eleven patients (19.6%) were deemed feasible, but prudent pre-operative planning is required due to complicated anatomy. The other 22 patients (39.3%) were unsuitable due to one or more exclusive criteria. Short prosthetic grafts (8), extreme graft angulations (11) and dissected supra-aortic branches (15) were the main reasons for exclusion. Conclusion - Endovascular repair is technically feasible in patients with prior ascending aortic replacement for type A dissection. Incompatible prosthetic ascending aorta and dissecting arch branches are the most common exclusive risk factors.

Outcome After Endovascular Repair of Ruptured Thoracic Aortic Aneurysm: A National Multicenter Study

Introduction - Ruptured descending thoracic aortic aneurysm (rDTAA) is an acute condition with high mortality requiring urgent treatment. The purpose of this multicenter study was to analyze the outcome of thoracic endovascular aortic repair (TEVAR) in patients with rDTAA. Methods - This is a nationwide retrospective study including all patients who underwent TEVAR for rDTAA at six major vascular university centers in Sweden between January 2000 and December 2015. Data from local hospital records and the Swedish vascular registry at the participating centres were reviewed. Outcome measures were analysed using Kaplan-Meier estimator and multivariable Cox-regression. Results - There were 140 patients (mean age 74.1±SD 8.8 [range: 34-91] years; 56% men), with rDTAA. The mean descending aortic aneurysm size was 64.8±19 mm. Hemothorax was present in 64% (89/139) of patients at admission. The median stent graft length was 218 mm (range: 30-800 mm) and the median number of stentgrafts used was 2.0 (range: 1-6). In 53 patients (37.9%), the left subclavian artery was covered to extend the proximal landing zone. Twenty-five patients (17.9%) required proximal revascularization; chimney left carotid artery (n=14), chimney left subclavian artery (n=7), carotid-carotid-subclavian bypass (n=2), and left carotid-subclavian bypass (n=2). The celiac trunc was covered in 15 cases (10.7%) to achieve adequate distal landing zone. A chimney was placed in the SMA in six cases (4.3%) and in the celiac trunc in one case (0.7%). In two patients a multi branched stent graft was used. In total, 61/136 patients (45%) had a major complication within 30-day post TEVAR. Stroke (n=20; 14.7 %) was the most common complication followed by paraplegia (n=13; 9.6%) and major bleeding (n=13; 9.6 %). There were no association between stent graft length or subclavian coverage and paraplegia (OR 1.00, 95% CI 0.998-1.01; P=0.32, and OR 0.56, 95% CI 0.14-2.31; P=0.42; respectively) or subclavian coverage and stroke (OR 1.40, 95% CI 0.46-4.31; P=0.56). Reinterventions were required in 27/137 patients (19.7%). Postoperative bleeding was the only major complication associated with reintervention (OR 3.39, 95% CI 1.05-11.0; P=0.042). Median follow-up time was 18.5 months (range: 0-132 months). The Kaplan-Meier estimated survival was 79.1% at 1 month, 70.8% at 3 months, 64.5% at 1 year, 45.0% at 3 years, and 30.9% at 5 years. Age (HR 1.04; 95 % CI 1.00-1.07; P=0.044), previous stroke (HR 2.31; 95 % CI 1.17-4.55; P=0.016), previous aortic surgery (HR 2.17; 95 % CI 1.18-3.99; P=0.012) as well as postoperative major bleeding (HR 4.29; 95 % CI 2.14-8.60; P=0.001), postoperative stroke (HR 2.73; 95 % CI 1.43-5.22; P=0.002), and renal failure (HR 7.82; 95 % CI 2.53-24.19; P=0.001) were all associated with mortality. Conclusion - This nationwide multicenter study of patients with rDTAA undergoing TEVAR showed acceptable short-term survival but the long-term survival is rather poor. The postoperative complication rate is high and reinterventions are required in one fifth of patients. Patient selection and optimization are of utmost importance to improve outcome.

Endovascular Treatment of Isolated Common Iliac Artery Aneurysms Using Iliac Branch Stent-grafts Without Aortic Component: A National Multicenter Registry

Endovascular Treatment of Isolated Common Iliac Artery Aneurysms Using Iliac Branch Stent-grafts Without Aortic Component: A National Multicenter Registry

Haemodynamics of Different Configurations of a Left Subclavian Artery Stent Graft for Thoracic Endovascular Aortic Repair

Branched stent grafts represent a viable option for left subclavian artery (LSA) revascularisation in patients treated by thoracic endovascular aortic repair (TEVAR) for Zone 2 lesions. This study investigated the haemodynamic performance of different LSA branched stent graft configurations as potential determinants of thrombotic and stroke risks. A three dimensional aortic arch geometry extracted from post-operative computed tomography images of a TEVAR patient using a single LSA branched aortic endograft was modified in silico to obtain ten potential LSA branched stent graft configurations: five down facing (0-5 - 10mm aortic protrusion with 10-12mm internal diameter), four curved (30-60° with antegrade/retrograde orientation), and one LSA orifice misalignment. The 0mm down facing stent graft was considered base configuration. Computational fluid dynamic analyses were performed to identify differences in pressure, energy, and wall shear stress (WSS) based parameters. Total pressure drop and energy loss variations among configurations were not greater than 5mmHg (6% of mean arterial pressure) and 5.7mW (0.7% of cardiac power), respectively. Protrusions up to 5mm created clinically insignificant flow disturbances. However, stent graft protrusions further into the aortic lumen created more complex haemodynamics, characterised by larger energy loss and more prominent flow recirculation. Protrusion greater than 5mm into the lumen was associated with larger areas of elevated maximum WSS (>20Pa) along the outer surface of the branched stent graft. Arterial haemodynamic characteristics are affected by LSA branched stent graft configurations, with pressure drops and energy losses likely to be clinically insignificant. The length of the stent graft protrusion into the aortic lumen generated the largest haemodynamic variations in the aortic system. Protrusions up to 5mm have smaller risk of potential thrombus generation. Conversely, larger protrusions into the aortic lumen showed more disturbed haemodynamics, suggesting a greater risk of potential thrombus formation, which may be clinically important over time.

Juxtarenal endovascular therapy with fenestrated and branched stent grafts after previous infrarenal repair

BackgroundThe treatment strategy for proximal aortic disease or type I endoleak after previous infrarenal repair has traditionally been open surgery. As endovascular treatment options with fenestrated and branched stent grafts increasingly rival open surgery for juxtarenal and pararenal aortic aneurysms, secondary proximal repair may similarly be performed endovascularly. Fenestrated stent grafts are individually tailored to each patient, whereas a more readily available “off-the-shelf” branched stent graft is often suitable in more urgent settings. MethodsAll patients who had been reoperated on with a proximal fenestrated or branched cuff after previous infrarenal endovascular or open repair from two tertiary referral centers between 2002 and 2015 were included in the analysis. Patients were retrospectively enrolled in a digital database. Data were collected from chart review and digital imaging. ResultsThere were 43 patients, 37 (86%) male and six (14%) female, who were treated. The indications for proximal endovascular repair were type I endoleak (58%), proximal aneurysm formation (30%), and stent graft migration (12%). Median follow-up time was 33 months (range, 3-120 months); 34 patients (79%) received a fenestrated cuff, and branched stent grafts were used in 8 (19%) cases. The majority of grafts had three (47%) or four (49%) fenestrations or branches. Technical success was accomplished in 93% of cases. In two cases, the celiac trunk occluded; in one case, the hepatic artery was overstented, and a renal artery could not be cannulated in one case. Median hospital stay was 5 days (range, 2-57 days). The 30-day mortality was 0%, and 1-year mortality was 5%. One patient died of an aneurysm-related cause during the study period. ConclusionsAn endovascular approach with fenestrated or branched stent grafts for treatment of proximal endoleak, proximal aneurysm formation, or pseudoaneurysms after previous infrarenal repair seems to be a valid alternative to open surgery.

Histologic Analysis with the Newly Designed Exoskeleton Seal® Stent-Graft in the Porcine Abdominal Aorta.

To investigate the technical feasibility of a novel exoskeleton Seal® stent-graft and analyze early histologic changes in the porcine abdominal aorta. Six pigs received an abdominal stent-graft (Group I), and six received an iliac branch stent-graft (Group II). Groups were subdivided as follows: Group Ia, which received three bifurcated main-body stent-grafts; Group Ib, which received three bifurcated main-body stent-grafts with both iliac graft-stents; Group IIa, which received three simple uni-iliac tapered stent-grafts; and Group IIb, which received three uni-iliac tapered tapered stent-grafts with right straight limb and left branched limb. Statistical analyses were performed with the Wilcoxon signed-rank test and mixed-model regression analysis. The primary technical success rate (< 24h) was 83% because of two acute thromboses in the lumen of the stented abdominal aorta immediately after stent-graft placement. At 4weeks, late thrombosis occurred in two pigs. Higher mean neointimal hyperplasia areas (23.5% vs. 16.2%; P = .047), neointimal hyperplasia thicknesses (545.5μm vs. 422.2μm; P = .001), and degrees of collagen deposition (2.71 vs. 2.33; P = .002) were observed at the bare-metal stent-graft compared with the proximal exoskeleton portion of the stent-graft, with no significant differences between the patent and occluded groups or among the four types of stent-grafts. The exoskeleton stent-graft demonstrates 66% of patency rate during 1-month follow-up due to four cases of thromboses; however, the endothelialization on the junction of proximal graft showed no significant differences between the patent and occluded groups. Further studies should investigate long-term outcomes with prolonged neointimal hyperplasia.

A Single Center Experience of In Situ Needle Fenestration of Supra-aortic Branches During Thoracic Endovascular Aortic Repair

To report the early results and technical details of in situ needle fenestration during thoracic endovascular aortic repair (TEVAR). Thirty-seven patients with thoracic aortic disease who underwent TEVAR with in situ needle fenestration in our department between February 2016 and April 2017 were included in this study. Their demographic information, clinical manifestations, periprocedural outcomes, and follow-up results were analyzed. In total, 96.4% of attempted fenestrations were successful (53/55). Fenestration of the left subclavian artery (LSA) was performed in 26 patients, fenestration of either the LSA or brachiocephalic trunk (BCT) plus the left common carotid artery (LCCA) was performed in six patients, and fenestration of the three supra-aortic branches was performed in five patients. In the three-fenestration group with five patients, the procedure was under the protection of a cardiopulmonary bypass. External iliac artery rupture occurred in one case. Cerebrovascular events occurred in three cases, and myocardial infarction occurred in one. One case had a branch stent graft stuck in the brachial artery. During a median follow-up of 21months, two patients developed retrograde type A dissection, and one was subsequently treated with a stent graft and BCT fenestration. One case presented with numbness in the fingertips of the left hand, and computed tomography angiography (CTA) indicated stenosis of the branch stent in the LSA. CTA examination revealed no endoleaks or expansion of the aortic aneurysms in any of the patients. In situ needle fenestration of endografts in the aortic arch is technically feasible, yielding acceptable short-term results in a selected patient cohort. Further studies are needed to determine mid- and long-term outcomes before more widespread adoption.

Use of the Octopus Technique for Endovascular Treatment of Complex Aortic Lesions

PurposeTo evaluate feasibility and effectiveness using the octopus endograft technique to treat complex aortic aneurysms (CAAs). Materials and MethodsEndovascular repair of CAAs, including thoracoabdominal aneurysms (TAAAs) and dissections involving major side branches, was performed at a single center from June 2014 to June 2017. Patients included 9 men and 2 women (mean age, 60.5 y; range, 40–89 y) were included. The octopus technique was applied using standard aortic grafts with branch stent grafts to preserve the renovisceral arteries. ResultsAortic pathologies comprised 3 mycotic aneurysms, 2 chronic dissections with acute rupture, 1 progressively enlarging chronic type B dissection, 1 acutely ruptured TAAA, and 4 unruptured TAAAs. Mean procedural and fluoroscopic times were 562 min (range, 324–840 min) and 183 min (range, 73–338 min), respectively. Three patients died within 1 month. Mean duration of follow-up was 26.3 months (range, 8–42 months) for remaining patients. Technical success rate of target vessel stent placement was 89.7% (35/39). Major complication rate was 45.5% (5/11), including 3 deaths, 1 permanent paraplegia, and 1 temporary paraplegia that resolved in 2 months. All 3 mycotic aneurysms with mean duration of follow-up of 29 months (range, 8–42 months) were excluded successfully without endoleak. ConclusionsThe octopus technique is feasible for treatment of CAAs requiring urgent management or with difficult anatomy without the use of available custom-made or off-the-shelf branched devices. The procedure carries substantial morbidity and mortality and requires further investigation for its long-term durability.

ITalian RegIstry of doUble inner branch stent graft for arch PatHology (the TRIUmPH Registry)

ObjectiveThe objective of this study was to assess early and midterm results after endovascular aortic arch repair using a double inner branch stent graft (DIBSG) in patients with aortic arch aneurysm or dissection unfit for open surgery. MethodsBetween 2012 and 2018, there were 24 patients with aortic arch disease who were treated with a single model of a DIBSG (Terumo Aortic, Glasgow, United Kingdom) in nine Italian cardiovascular centers. We investigated technical success, mortality, occurrence of major complications, and need for reintervention in a multicenter, nonrandomized, retrospective fashion. ResultsThe in-hospital mortality rate was 16.7%. Cerebrovascular events occurred in 25% of patients and major strokes in 12.5%. Two patients experienced a retrograde dissection (8.3%), whereas none reported any type I or type III endoleak. During a mean follow-up of 18 months (range, 1-60 months), one patient died of a nonaortic cause and one reported a nonarch-related major stroke. No late secondary intervention was needed during the follow-up. Excluding from the analysis the first six patients treated until 2014 as part of the learning curve, in-hospital mortality, major stroke, and retrograde dissection rates were 11.1%, 11.1%, and 5.6%, respectively. ConclusionsEndovascular aortic arch repair using this model of DIBSG is feasible, and results are acceptable for a new technique in a high-risk subset of patients. Operative mortality suffers the effect of a learning curve, whereas midterm aorta-related survival is promising. Endovascular repair of aortic arch disease with a DIBSG should always be considered to give high-risk patients a chance of repair. Large-scale studies are needed to assess the long-term durability of this technique.

Predictive Numerical Simulations of Double Branch Stent-Graft Deployment in an Aortic Arch Aneurysm

Total endovascular repair of the aortic arch represents a promising option for patients ineligible to open surgery. Custom-made design of stent-grafts (SG), such as the Terumo Aortic® RelayBranch device (DB), requires complex preoperative measures. Accurate SG deployment is required to avoid intraoperative or postoperative complications, which is extremely challenging in the aortic arch. In that context, our aim is to develop a computational tool able to predict SG deployment in such highly complex situations. A patient-specific case is performed with complete deployment of the DB and its bridging stents in an aneurysmal aortic arch. Deviations of our simulation predictions from actual stent positions are estimated based on post-operative scan and a sensitivity analysis is performed to assess the effects of material parameters. Results show a very good agreement between simulations and post-operative scan, with especially a torsion effect, which is successfully reproduced by our simulation. Relative diameter, transverse and longitudinal deviations are of 3.2 ± 4.0%, 2.6 ± 2.9mm and 5.2 ± 3.5mm respectively. Our numerical simulations show their ability to successfully predict the DB deployment in complex anatomy. The results emphasize the potential of computational simulations to assist practitioners in planning and performing complex and secure interventions.