Advanta V12 Research Articles

Assessment of Bridging Stents in In Situ Laser Fenestrations of Aortic Endografts With Intravascular Ultrasound

ObjectiveTreatment of complex aortic aneurysms with the in situ laser fenestration (ISLF) technique involves implantation of a balloon expandable stent graft (bSG) in the created fenestration. Adequate expansion of this bSG is of importance both to achieve seal and to ensure target vessel stability. This experimental study assessed the expansion rate of different bSGs in the ISLF setting using intravascular ultrasound (IVUS). MethodsA commercially available aortic endograft was used to test the laser fenestration technique (Zenith Alpha, Cook Medical LLC, Bloomington, IN, USA). The ISLF was stented with the following bSGs: two Gore Viabahn VBX balloon expandable endoprostheses (WL Gore & Associates, Bloomington, IL, USA), three BeGraft Peripheral and three BeGraft Plus (Bentley InnoMed GmbH; Hechingen, Germany), and three Advanta V12 (Atrium, Hudson, NH, USA). The bSGs were expanded in three steps: (1) nominal, (2) rated burst pressure, and (3) dilatation with a non-compliant balloon at 15 atmospheres. After each step, an IVUS assessment of the bSG minimal diameter and the area at the fenestration (FA) and in a fully expanded segment distal to the fenestration (SA) was performed. A mean of the three IVUS measurements was used as the value for comparison. An insufficient bSG expansion was defined as a mean of FA/SA of < 0.8 (i.e., < 80% expansion). ResultsThe VBX was the only bSG that could be expanded to its intended diameter (i.e., at least 80%) at nominal pressure. The BeGraft Peripheral and BeGraft Plus showed the lowest expansion degrees after nominal and rated burst pressure. All bSGs that were tested reached a sufficient expansion degree after the use of a higher pressure balloon. ConclusionIn this ex vivo experiment, a dilatation up to nominal pressure showed satisfactory expansion only for the VBX. The consistency of the results when applied to the different types of stent grafts that were analysed reflects structural stent graft specific issues to consider when choosing the right device in cases of ISLF.

Renal and Visceral Artery Configuration During the First Year of Follow-Up After Fenestrated Aortic Aneurysm Repair Using the Anaconda Stent-graft: A Prospective Longitudinal Multicenter Study With ECG-Gated CTA Scans.

The performance of fenestrated endovascular aortic aneurysm repair (FEVAR) may be compromised by complications related to the dynamic vascular environment. The aim of this study was to analyze the behavior of FEVAR bridging stent configurations during the cardiac cycle and during follow-up to improve our understanding on treatment durability. Twenty-one patients presenting with complex abdominal aortic aneurysms (AAAs; 9 juxtarenal/6 pararenal/3 paravisceral/1 thoracoabdominal aortic aneurysm type IV), treated with a fenestrated Anaconda (Terumo Aortic, Inchinnan, Scotland, UK) with Advanta V12 bridging stents (Getinge, Merrimack, NH, USA), were prospectively enrolled in a multicenter observational cohort study and underwent electrocardiogram (ECG)-gated computed tomographic angiography (CTA) preoperatively, at discharge, 7-week, and 12-month follow-ups. Fenestrated endovascular aortic aneurysm repair stability was assessed considering the following variables: branch angle as the angle between the aorta and the target artery, end-stent angle as the angle between the end of the bridging stent and the native artery downstream from it, curvature and tortuosity index (TI) to describe the bending of the target artery. Body-bridging stent stability was assessed considering bridging stent flare lengths, the distances between the proximal sealing stent-ring and fenestrations and the distance between the fenestration and first apposition in the target artery. Renal branch angles significantly increased after FEVAR toward a perpendicular position (right renal artery from median 60.9°, inter quartile range [IQR]=44.2-84.9° preoperatively to 94.4°, IQR=72.6-99.8°, p=0.001 at 12-month follow-up; left renal artery [LRA], from 63.7°, IQR=55.0-73.0° to 94.3°, IQR=68.2-105.6°, p<0.001), while visceral branch angles did not. The mean dynamic curvature only decreased for the LRA from preoperative (3.0, IQR=2.2-3.8 m-1) to 12-month follow-up (1.9, IQR=1.4-2.6 m-1, p=0.027). The remaining investigated variables did not seem to show any changes over time in this cohort. Fenestrated endovascular aortic aneurysm repair for complex AAAs using the Anaconda fenestrated stent-graft and balloon-expandable Advanta V12 bridging stents demonstrated stable configurations up to 12-month follow-up, except for increasing renal branch angles toward perpendicular orientation to the aorta, yet without apparent clinical consequences in this cohort. This study provides detailed information on the cardiac-pulsatility-induced (dynamic) and longitudinal geometry deformations of the target arteries and bridging stents after fenestrated endovascular aortic aneurysm repair (FEVAR) up to 12-month follow-up. The configuration demonstrated limited dynamic and longitudinal deformations in terms of branch angle, end-stent angle, curvature, and tortuosity index (TI), except for the increasing renal branch angles that go toward a perpendicular orientation to the aorta. Overall, the results suggest that the investigated FEVAR configurations are stable and durable, though careful consideration of increasing renal branch angles and significant geometry alterations is advised.

Long Term Outcomes of the Advanta V12 Covered Bridging Stent for Fenestrated and Branched Endovascular Aneurysm Repair in 1 675 Target Vessels

Long Term Outcomes of the Advanta V12 Covered Bridging Stent for Fenestrated and Branched Endovascular Aneurysm Repair in 1 675 Target Vessels

Editor's Choice – Long Term Outcomes of the Advanta V12 Covered Bridging Stent for Fenestrated and Branched Endovascular Aneurysm Repair in 1 675 Target Vessels

To report outcomes of the Advanta V12 as a covered bridging stent in fenestrated and branched endovascular aneurysm repair (F/BEVAR). Patients treated with F/BEVAR and followed in a single centre receiving the Advanta V12 as a covered bridging stent between January 2010 and May 2020 were included. A total of 636 patients (543 men) were analysed. A total of 1 675 target vessels (TVs) were bridged with the Advanta V12. Estimated TV patency at one, five, and eight years was 99.1% ± 0.2%, 96.9% ± 0.5% and 96.2% ± 0.7%, respectively. Estimated patency at eight years was 98.1% ± 0.5% for fenestrations and 87.3% ± 2.9% for branches (p < .001). Estimated patency of renal arteries was statistically significantly lower for those targeted with branches compared with fenestrations (p= .001). Multivariable analysis showed that targeting a TV with a branch compared with a fenestration was the only independent risk factor for occlusion during follow up (hazard ratio 6.41, 95% CI 3.4 - 11.9; p < .001). Estimated freedom from endoleak at one, five, and eight years was 99.4% ± 0.2%, 96.4% ± 0.6%, and 95.4% ± 0.8%, respectively. Estimated freedom from target vessel instability (TVI) at one, five, and eight years was 98.5% ± 0.3%, 93.0% ± 0.8%, and 91.3% ± 1%, respectively. Estimated freedom from TVI at eight years was 93.2% ± 0.9% for fenestrations and 82.7% ± 3.5% for branches (p < .001). Estimated freedom from TVI was statistically significantly lower for renal arteries targeted with branches compared with those targeted with fenestrations (p < .001) CONCLUSION: The Advanta V12 shows excellent technical success rates as a covered bridging stent in F/ΒEVAR. Late outcomes remain good with low rates of TV occlusion, endoleak, and re-intervention. Renal arteries targeted with branches demonstrated a higher risk of occlusion and instability compared with those targeted with fenestrations.

In Vitro Radiological Evaluation of Different Types of Chimney Stents Using a Silicon Flow Model with Adjustable Physiological Simulating Conditions

To evaluate invitro the performance of invivo published covered or bare metal chimney stents (ChSs) in combination with the Endurant II abdominal endograft (Medtronic) as the only CE approved main graft (MG) in the treatment of juxtarenal abdominal aortic aneurysms with the chimney endovascular aneurysm repair (chEVAR) technique. Bench top experimental study. A silicon flow model with adjustable physiological simulating conditions and patient based anatomy was used to test nine different MG-ChS combinations: Advanta V12 (Getinge); BeGraft+ (Bentley); VBX (Gore & Associates Inc.); LifeStream (Bard Medical); Dynamic (Biotronik); Absolute Pro (Abbott); double Absolute Pro; Viabahn (Gore) lined with Dynamic; and Viabahn lined with EverFlex (Medtronic). Angiotomography was performed after each implantation. DICOM data were analysed blindly twice per observer by three independent experienced observers. Each blinded evaluation was performed at one month intervals. The main analysed parameters were the area of gutters, MG and ChS maximum compression, and the presence of infolding. Bland-Altman analysis confirmed adequate results correlation (p < .05). Each employed ChS showed significantly different performance favouring the balloon expandable covered stent (BECS). The smallest gutter area was seen in the combination with Advanta V12 (0.26 cm2). MG infolding was observed in all tests. The lowest ChS compression was observed in the combination with BeGraft+ (compression 4.91%, D ratio 0.95). In our model, BECSs showed higher angulations than bare metal stents (BMSs) (p < .001). This invitro study shows the variability of performance with each theoretically possible ChS and explains the divergent ChS outcomes in the published literature. BECS in combination with the Endurant abdominal device confirms their superiority vs. BMS. The presence of MG infolding in each test underlines the need for prolonged kissing ballooning. Angulation evaluation and comparison with other invitro and invivo publications demands the need for further investigation in transversely or upwardly oriented target vessels.

Results of endovascular treatments of Trans-Atlantic Inter-Society Consensus C or D aortoiliac occlusive disease involving the aortic bifurcation.

The current study aims to report midterm results of patients treated with endovascular intervention, kissing stent, or covered endovascular reconstruction of the aortic bifurcation, for Trans-Atlantic Inter-Society Consensus C or D aortoiliac occlusive disease involving the aortic bifurcation. Eighteen patients who have intermittent claudication or chronic limb threatening ischemia with Trans-Atlantic Inter-Society Consensus C or D aortoiliac occlusive disease involving the aortic bifurcation enrolled to the study between January 2018 and January 2021. Kissing stents, Advanta V12 (Atrium, Getinge Group), were used in 13 patients, and the covered endovascular reconstruction of the aortic bifurcation technique was used in 4 patients to reconstruct the aortic bifurcation. The patients were followed for a median of 49 months (min. 2, max.58 months). Patency rates, mortality, morbidities, and reinterventions were recorded. The mean age of the patients was 60.4 ± 10 years. Technical success was achieved in 94.4% of the patients, but one patient had to convert to open surgery. Primary patency rate of the remaining patients was 85.6% at 58 months. Target lesion revascularization rate was 11.7%. One patient had successful reintervention for in stent restenosis, and secondary patency rate was 93.3% at 58 months. Limb salvage rate was 84.6% during the follow-up. Two patients had myocardial infarction (11.1%) and one mortality (5.6%) occurred because of cerebrovascular event in the follow-up. Endovascular techniques can be used safely for reconstruction of the aortic bifurcation in Trans-Atlantic Inter-Society Consensus C or D aortoiliac occlusive disease in selected patients who have high risk for open surgery. Covered endovascular reconstruction of the aortic bifurcation is the only technique that showed patency rates approaching open surgery in treatment of aortoiliac occlusive disease involving the aortic bifurcation to date. Although promising patency results were achieved with kissing-covered stents, long-term patency rates were still lower than those achieved with open surgery. Further randomized controlled studies comparing the long-term results of these techniques are needed.

Three-Dimensional Geometric Analysis of Balloon-Expandable Covered Stents Improves Classification of Complications after Fenestrated Endovascular Aneurysm Repair.

In balloon-expandable covered stent (BECS) associated complications after fenestrated endovascular aneurysm repair (FEVAR), geometric analysis may determine the cause of failure and influence reintervention strategies. This study retrospectively classifies BECS-associated complications based on computed tomographic angiography (CTA) applied geometric analysis. BECS-associated complications of FEVAR-patients treated in two large vascular centers between 2012 and 2021 were included. The post-FEVAR CTA scans of complicated Advanta V12 BECSs were analyzed geometrically and complications were classified according to its location in the BECS. BECS fractures were classified according to an existing classification system. In 279 FEVAR-patients, 34 out of the 683 included Advanta V12 BECS (5%) presented with a complication. Two Advanta V12 complications occurred during the FEVAR procedure and 32 occurred during follow-up of which five post-FEVAR CTA scans were missing or not suitable for analysis. In the remaining 27 BECSs complications were classified as (endoleaks (n = 8), stenoses (n = 4), occlusions (n = 6), fractures (n = 3), and a combination of complications (n = 6)). All BECSs associated complications after FEVAR with available follow up CTA scans could be classified. Geometric analysis of BECS failure post-FEVAR can help to plan the reintervention strategy.

Correction to: Large Diameter Advanta V12 Covered Stent Trial for Coarctation of the Aorta: COARC Study.

Correction to: Large Diameter Advanta V12 Covered Stent Trial for Coarctation of the Aorta: COARC Study.

In Vitro Geometry Analysis of Fenestrations in Endovascular Aneurysm Repair

Purpose: Changes in the flared end of balloon-expandable covered stent (BECS) may precede BECS-associated complications but are not regularly assessed with computed tomographic angiography (CTA) after fenestrated endovascular aneurysm repair (FEVAR). Validation of the flare geometric analysis (FGA) and assessment of intraobserver and interobserver variability are investigated in this study. Methods: Two series of 3 BeGraft BECSs (Bentley InnoMed GmbH, Hechingen, Germany) and 1 series of 3 Advanta V12 BECSs (Getinge AB, Göteborg, Sweden) were deployed in 3 side branches (45°, 60°, and 90° aortic branch angles) of an aorta phantom model. A standard post-FEVAR CTA scan was acquired. Computed tomographic angiography–derived measurements consisted of centerline reconstructions and placement of 3-dimensional coordinate markers by 2 observers in a vascular workstation. Flare geometric analysis calculates 3 BECS parameters: the circumferential flare-to-fenestration distance (FFD), which is the distance from the proximal end of the flare to fenestration, and diameters at the proximal end of the flare (Dflare) and at the fenestration (Dfenestration). Computed tomographic angiography–derived measurements were validated against microscopy measurements. Bland-Altman plots were used to determine the intraobserver and interobserver variability of the BECS parameters and intraclass correlation coefficient (ICC). Results: For each BECS, the FFD at 4 equidistant quadrants of the circumference, Dflare, and Dfenestration were calculated. The mean difference and repeatability coefficient (RC) of the validation were 0.8 (2.1) mm for FFD, 0.4 (1.0) mm for Dflare, and −0.2 (1.2) mm for Dfenestration. The mean intraobserver and interobserver difference (RC) was 0.5 (1.6) mm and 0.7 (2.6) mm for FFD, 0.1 (0.6) mm and 0.1 (0.7) mm for Dflare, and −0.1 (0.8) mm and −0.8 (1.0) mm for Dfenestration. The mean ICC of intraobserver variability was 0.86 for FFD, 0.94 for Dflare, and 0.78 for Dfenestration. The mean ICC of interobserver variability was 0.77 for FFD, 0.92 for Dflare, and 0.48 for Dfenestration. Conclusion: This study showed that FGA of the flared ends of BECS can be performed with high accuracy in a phantom model, with good intraobserver and interobserver variability. Flare geometric analysis can be used to determine flare geometry of the BECS on standard post-FEVAR CTA scans.

Large Diameter Advanta V12 Covered Stent Trial for Coarctation of the Aorta: COARC Study.

Covered stent implantation for treatment of coarctation of the aorta (CoA) is effective and can prevent aortic wall injury. Prospective studies with long-term follow-up, including imaging, are lacking. We report the acute and long-term outcomes for use of the Large Diameter Advanta V12 covered stent for treatment of native and recurrent CoA. A prospective, multicenter, nonrandomized study was performed including 70 patients (43 male), median age 17 years, median weight 57.4 kg with CoA who underwent implantation of the Large Diameter Advanta V12 covered stent. Annual follow-up for 5 years included Doppler echocardiography to calculate diastolic velocity: systolic velocity ratio. CoA diameter increased from 5.6±3.6 to 14.9±3.9 mm (P<0.0001) and the pressure gradient decreased from 35.8±16.2 to 5.6±7.9 mm Hg (P<0.0001). Preimplantation diastolic velocity:systolic velocity of 0.6±0.16 dropped to 0.34±0.13 (P<0.0001) and was maintained at 5 years. Computed tomography angiograms at 12 months postimplantation demonstrated the stent:transverse arch diameter to be similar, 0.91±0.09 to postprocedure 0.86±0.14. Major adverse vascular events at 30 days and 12 months were 1.4% and 4.3%, respectively. Significant adverse events included three patients who required stent implantation to treat infolding. There were no mortalities. The Large Diameter Advanta V12 covered stent is safe and effective for the treatment of CoA with an immediate and sustained reduction of the pressure gradient over 12 months and 5 years as assessed by preimplantation and postimplantation Doppler echocardiography and 12-month computed tomography angiography. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00978952. URL: http://www.anzctr.org.au; Unique identifier: ACTRN12612000013864.

One-Year Results of ZBIS Iliac Branch Device With an Off-Label Connection Limb

Purpose: The purpose of this article is to study 1-year results of Zenith branch iliac endovascular graft (ZBIS) with the off-label use of a 13 mm spiral Z limb to connect to the aortic main body. Materials and Methods: A retrospective review from 2015 to 2019 of all iliac branch devices (IBDs) was performed at 1 institution that were connected to an aortic main body with a 13 mm spiral Z limb and had at least 1-year follow-up with computed tomography (CT). Primary endpoints are freedom from ZBIS separation from the connection limb, endoleak (EL), or reintervention at 1 year. Secondary endpoints are primary and secondary ZBIS patency, presence of any EL, and aortic reinterventions. Results: Of 149 IBDs implanted in this period, 45 ZBIS in 35 patients were connected with a 13 mm limb and had a 1-year CT; 97% of patients had common iliac artery (CIA) aneurysms, 7% of patients had hypogastric artery (HA) aneurysms, and 30% of patients had bilateral ZBIS implantation. Technical success was 98%. In 84% of cases, the Advanta V12 was used as the HA mating stent; 56% of patients had an EL, mostly type II, which resolved spontaneously in 70% at 1 year, and 9% of ZBIS required reinterventions at 1 year (2 for thrombosis, 2 for type Ic EL from HA mating stent). One-year ZBIS primary patency and secondary patency were 96% and 100%, respectively. No EL was noted to be related to the 13 mm connection limb. No migration or separation of the devices occurred. Conclusions: The use of 13 mm spiral Z limb to connect a ZBIS with the main body in our series yields a high technical success rate and good 12-month outcomes without device separation or migration.

Mechanical Behaviour of Fenestrations in Current Aortic Endografts

The aim of this study was to assess the mechanical characteristics of current commercially available fenestrated endografts (FE). The performance of the fenestrations according to the design were compared as the relationship between a bridging covered stent graft (CSG) and the fenestration. A total of 21 Zenith (Cook Medical, Bloomington, IN, USA) and 17 Anaconda (Terumo Company, Inchinnan, UK) fenestrations were studied. Radial extension tests were performed, inserting two half cylinders spaced up to 2 mm in a 7 mm diameter fenestration from each device. Branch pull out force was measured to test the stability of the assembly with a calibrated 8 mm branch and two CSGs: Advanta V12 (Atrium Medical; Hudson, NH, USA) and BeGraft Peripheral Stent Graft (Bentley InnoMed GmbH, Hechingen, Germany). A branch was inserted in both the 7 mm diameter fenestrations and in a control 7 mm fenestration. Fatigue tests were performed on the devices to assess long term outcomes of the endograft. Over a 2 mm vertical displacement, the resulting loading curves look similar for both devices. The force value level was 33.4 ± 6.9 N for the Cook fenestration and 54.45 ± 18 N for the Anaconda fenestration (p= .001). With respect to an 8 mm calibrated branch, the required extraction strength from the fenestration was statistically significantly greater with the Anaconda device (9.5 ± 4.7 N vs. 4.49 ± 0.28 N; p= .001). The required strength to extract the V12 CSG from a control cylindered shape was statistically significantly higher than for the BeGraft CSG (6.75 ± 2.86 N vs. 1.83 ± 0.67 N; p= .003). The surface area of the fenestration of the Cook device was increased with cycling (7 200 cycles) compared with the Anaconda device (15.5% vs. 6.5% hole surface area increase). The mechanical performance of the fenestration can be fine tuned by considering its design. A CSG optimising the performance of the fenestration and the CGS-fenestration interface could reduce the risk of leakage in clinical practice.

Iatrogenic Giant Inferior Vena Cava

A 70 year old female patient with heart failure and severe pulmonary hypertension had an elevated cardiac output and high oxygen content in the inferior vena cava (IVC) during cardiac catheterisation. (A) Computed tomography angiography showed a large arteriovenous fistula (arrowhead) between the left common iliac vessels and an enlarged contrast enhanced IVC (asterisk), most likely caused by overlooked vessel trauma during a posterior L5–S1 spinal fusion procedure performed a decade previously. (B) The iliac artery defect was closed using an Advanta V12 9 × 32 mm covered stent (Getinge, Gothenburg, Sweden; arrow). The patient’s cardiovascular condition improved significantly.Image 1

Outcomes of Advanta V12 Covered Stents After Fenestrated Endovascular Aneurysm Repair

Purpose: Fenestrated endovascular aneurysm repair (FEVAR) is a well-established endovascular treatment option for pararenal abdominal aortic aneurysms in which balloon-expandable covered stents (BECS) are used to bridge the fenestration to the target vessels. This study presents midterm clinical outcomes and patency rates of the Advanta V12 BECS used as a bridging stent. Methods: All patients treated with FEVAR with at least 1 Advanta V12 BECS were included from 2 large-volume vascular centers between January 2012 and December 2015. Primary endpoints were freedom from all-cause reintervention, and freedom from BECS-associated complications and reintervention. BECS-associated complications included significant stenosis, occlusion, type 3 endoleak, or stent fracture. Secondary endpoints included all-cause mortality in-hospital and during follow-up. Results: This retrospective study included 194 FEVAR patients with a mean age of 72.2±8.0 years. A total of 457 visceral arteries were stented with an Advanta V12 BECS. Median (interquartile range) follow-up time was 24.6 (1.6, 49.9) months. The FEVAR procedure was technically successful in 93% of the patients. Five patients (3%) died in-hospital. Patient survival was 77% (95% CI 69% to 84%) at 3 years. Freedom from all-cause reintervention was 70% (95% CI 61% to 78%) at 3 years, and 33% of all-cause reinterventions were BECS associated. Complications were seen in 24 of 457 Advanta V12 BECSs: type 3 endoleak in 8 BECSs, significant stenosis in 4 BECSs, occlusion in 6 BECSs, and stent fractures in 3 BECSs. A combination of complications occurred in 3 BECSs: type 3 endoleak and stenosis, stent fracture and stenosis, and stent fracture and occlusion. The freedom from BECS-associated complications for Advanta V12 BECSs was 98% (95% CI 96% to 99%) at 1 year and 92% (95% CI 88% to 95%) at 3 years. The freedom from BECS-associated reinterventions was 98% (95% CI 95% to 100%) at 1 year and 94% (95% CI 91% to 97%) at 3 years. Conclusion: The Advanta V12 BECS used as bridging stent in FEVAR showed low complication and reintervention rates at 3 years. A substantial number of FEVAR patients required a reintervention, but most were not BECS related.

Midterm results after covered stenting of the superior mesenteric artery

ObjectiveDespite the continuing controversy of covered stents (CS) vs bare metal stents, the use of CS in mesenteric occlusive disease (MOD) has been recommended by expert centers. The aim of this study was to report midterm results with CS of the superior mesenteric artery. MethodsBetween January 2014 and October 2019, patients with MOD with a severe atheromatous stenosis or occlusion of the superior mesenteric artery treated by mesenteric CS were included. Clinical presentation included both acute mesenteric ischemia (AMI), chronic mesenteric ischemia, and asymptomatic patients planned for major surgery. Demographics, procedure details, and follow-up data were prospectively collected and retrospectively reviewed. Study end points included primary patency, primary assisted patency, and secondary patency. ResultsDuring the study period, 86 patients (mean age, 70 ± 9 years; 57% males) were included. Clinical presentation was AMI (n = 42 [49%]), chronic mesenteric ischemia (n = 31 [36%]), and asymptomatic (n = 13 [15%]). The technical success rate was 97%. A total of 96 stents were implanted, including 86 proximal CS (Advanta V12, n = 73; Lifestream, n = 13). The mean length and mean diameter of the CS were 31.5 ± 6.3 mm and 6.9 ± 0.5 mm, respectively. Additional distal bare metal stents were used in 10 patients (12%) to overcome a kinking (n = 9) or a dissection (n = 1) downstream of the CS. All postoperative deaths occurred in patients with AMI (n = 11, 13%). During a median follow-up of 15.6 months (95% confidence interval [CI], 15.6 ± 3.6 months), 12 patients (14%) underwent reinterventions for either stent misplacement (n = 3), stent recoil (n = 3), stent thrombosis (n = 2), de novo stenosis at the distal edge of the CS (n = 2), or gastric ischemia (n = 1). At 1 year, overall the primary patency, primary assisted patency, and secondary patency rates were 83% (95% CI, 83% ± 9%), 99% (95% CI, 99% ± 3%), and 99% (95% CI, 99% ± 3%), respectively. At 2 years, the overall primary patency, primary assisted patency, and secondary patency rates were 76% (95% CI, 76% ± 13%), 95% (95% CI, 95% ± 8%) and 95% (95% CI, 95% ± 8%), respectively. ConclusionsMesenteric CS provide very satisfactory midterm results in patients with MOD, with an excellent primary assisted patency rate at 2 years, at the price of a significant reintervention rate.

Fatigue Resistance of the Advanta V12/iCast and Viabahn Balloon-Expandable Stent-Graft as Bridging Stents in Experimental Fenestrated Endografting

Purpose: Bridging stents undergo millions of cycles during respiratory movements of the kidneys throughout the patient’s life. Thus, understanding the response of fabric and endoskeleton of the stent to cyclic loading over the time is crucial. In this study, we compare the fatigue resistance of the Viabahn Balloon-Expandable stent-graft (VBX) with the widely used Advanta V12/iCast under prolonged stress induction. Materials and Methods: A polyester test sheet with 10 fenestrations was used simulating a fenestrated endograft. Five 6×59 mm VBX stent-grafts and five 6×58 mm Advanta stent-grafts were implanted into 6×6 mm fenestrations. The stents were flared with a 10×20 mm PTA (percutaneous transluminal angioplasty) catheter and connected with a fatigue stress machine. All stent-grafts were evaluated by microscopy and radiography at baseline and after regular intervals until 50,000,000 cycles were applied, simulating a life span of approximately 75 months. Freedom from fracture (FF), freedom from initial polytertafluoroethylene (PTFE) changes (FIC), and from PTFE breakpoint (FBP, all-layer defect) were calculated. Results: Digital radiographic images did not show any stent fracture in both groups after 50,000,000 cycles. The VBX stent-graft was free from any all-layer defects at the conclusion of 50,000,00 cycles resulting in a significant higher FBP compared with Advanta V12 (50,000,000 vs 33,400,000; p<0.01). All-layer defects were observed only in the Advanta group. Two of 5 Advanta stents showed early penetration of the nitinol ring causing a defect of PTFE. Regarding FIC, there was no significant difference between the stents (3,400,000 in VBX vs 3,200,000 in Advanta). Conclusions: In fatigue tests simulating respiration movements, VBX and Advanta V12 performed equally well in terms of fracture resistance and freedom from initial PTFE changes. VBX maintained freedom from PTFE breakpoint throughout the full 50,000,000 cycles. All-layers defects were detected only in Advanta and were mainly caused by penetration of the nitinol ring through the PTFE.

Changes in Target Vessel Anatomy Following Fenestrated Endovascular Aneurysm Repair: Midterm Results

Purpose: To analyze the changes in target vessel (TV) anatomy after fenestrated endovascular aneurysm repair (fEVAR) during midterm follow-up. Materials and Methods: A retrospective single-center study analyzed 56 patients (mean age 71±7 years; 49 men) who underwent fEVAR using custom-made stent-grafts (22 Zenith and 34 Anaconda) between June 2010 and July 2016. Advanta V12 (V12; 74, 53%) and BeGraft (BeG; 66, 47%) stent-grafts were used to bridge to the 140 TVs. Measurements of the TV deviation at the aortic origin, the vessel shift distal to the bridging stent-graft (BSG), and the outer and inner BSG curve lengths were performed after 3-dimensional reconstruction of the serial computed tomography angiography scans. The results of the measurements for the main devices, the TVs, and the bridging stent-grafts were compared using univariable and multivariable analysis. Results: Of the 140 BSGs examined (74 V12s and 66 BeGs), 393 measurements (38 celiac trunks, 102 superior mesenteric arteries, 121 left renal arteries, and 132 right renal arteries) were analyzed. The outer/inner BSG curve length ratio was larger after implantation of Zenith devices compared with Anaconda (p<0.001). The vessel shift distal to the BSG was significantly associated with the interaction of the TV and type of BSG only in the univariable analysis (p=0.001). There were no significant changes of the TV deviation at the aortic origin. Only the outer BSG curve length was significantly associated with TV complications (p=0.033). Median follow-up was 24 months (range 2–61). The BSG curve length ratio showed a significant increase over time (p<0.001) but did not differ between the BeG and V12 (p=0.381). Conclusion: No difference was found between the V12 and the BeG stent-grafts regarding anatomical TV changes during midterm follow-up after fEVAR. Both stent-grafts adapt to the TV anatomy over time, and moderate anatomical changes seem to be tolerated without increasing the risk for TV complications. The type of main device also influences the TV anatomy.

Gutter Characteristics and Stent Compression of Self-Expanding vs Balloon-Expandable Chimney Grafts in Juxtarenal Aneurysm Models

Purpose: To assess in silicone juxtarenal aneurysm models the gutter characteristics and compression of different types of chimney graft (CG) configurations. Materials and Methods: Fifty-seven combinations of Excluder C3 or Conformable Excluder stent-grafts (23, 26, and 28.5 mm) were deployed in 2 silicone juxtarenal aneurysm models with 3 types of CGs: Viabahn self-expanding (VSE; 6 and 13 mm) or Viabahn balloon-expandable (VBX; 6, 10, and 12 mm) stent-grafts and Advanta V12 balloon-expandable stent-grafts (ABX; 6 and 12 mm). Setups were divided into 4 groups on the basis of increasing CG and main graft (MG) diameters. Two independent observers assessed gutter size and type as well as CG compression on computed tomography scans using postprocessing software. Results: In the smaller diameter combinations (6-mm CG and 23-, 26-, and 28.5-mm MGs), both VSE (p=0.006 to 0.050) and ABX (p=0.045 to 0.050) showed lower gutter areas and volumes compared with VBX. In turn, the VBX showed a nonsignificant tendency to decreased compression, especially compared to ABX. Use of the Excluder C3 showed a 6-fold increase in type A1 gutters (related to type Ia endoleak) as compared to the Conformable Excluder (p=0.018). Balloon-expandable stent-grafts (both ABX and VBX) showed a 3-fold increase in type A1 gutters in comparison with self-expanding stent-grafts (p=0.008). Conclusion: The current study suggests that use of the Conformable Excluder in combination with VSE chimney grafts is superior to the other tested CG/MG combinations in terms of gutter size, gutter type, and CG compression.

Our experience with graft stents in the treatment of diseases of the main arteries of the brain

Objective – to study the efficacy and safety of stent grafts in the treatment of diseases of the cerebral arteries.Materials and methods. It was analysed results of treatment of 6 patients (3 men and 3 women) with disease of the main arteries of the brain, where stent graft was used. The youngest patient was 35 years old, the oldest was 60. Results were evaluated by data of somatic and neurological examination, selective cerebral angiography, computer and magnetic resonance imaging. Surgery performed within 1 to 3 months from the onset of the disease. On a modified Rankin scale four patients have 0 point, two have 1 point. All patients received double disaggregant therapy, clopidogrel 75 mg, and aspirin 100 mg per day before the intervention. Sensitivity to clopidogrel was determined by the method of light transmission aggregate. All interventions were performed under general anesthesia; the duration of the intervention ranged from 25 to 90 minutes, average mean was 45 minutes. Used for stent surgery Atrium Advanta V12 and Graftmaster.Results. In four cases, stent implantation had no technical difficulties. In two cases, technical difficulties arose due to the structural features of the stent system, in particular, the rigid system distal to the stent itself, which limits the stent navigation in curved areas. In one case, due to the use of rigid delivery system and implantation of the stent by the method of retrograde opening from the guide catheter was able to implant at the level of the aneurysm. In one case, the stent was implanted without covering the distal part of the artery, after stent implantation a stasis of contrast fluid in the aneurysm cavity was noted. Control angiography after 6 months to demonstrate total exclusion of an aneurysm from the bloodstream. Using the features of the stent, it was possible to separate the arteriovenous complicity between the vertebral artery and the paravertebral venous plexus with complete reconstruction of the artery. There were no intraoperative and postoperative complications. Duration of stay of patients in hospital 3–5 days. In all cases, reconstruction of the artery was achieved with the exception of an aneurysm from the bloodstream or disconnection of the arteriovenous shunt.Conclusions. The preliminary accumulated results of the use of stent grafts in the aneurysms of the extracranial carotid section indicate that this technique has advantages over “conservative surgical treatment” by reducing surgical trauma, no risk of damage to the cranial nerves, shorter stay time. In case of erosive bleeding and arteriovenous joints, the use of stent graft should be considered as a method of choice.

Outcomes of bridging stent grafts in fenestrated and branched endovascular aortic repair

ObjectiveUntil today, no dedicated bridging stent graft (BSG) has been available for use in fenestrated and branched endovascular aneurysm repair (F/BEVAR). The purpose of this study was to evaluate the clinical performance of the well-known Advanta/iCast V12 (Getinge Maquet, Rastatt, Germany) and the new Viabahn VBX (W. L. Gore & Associates, Flagstaff, Ariz) balloon-expandable stent graft in F/BEVAR. MethodsRetrospective analysis of prospectively collected data was performed. Inclusion criteria were treatment with fenestrated or branched endografts for complex aortic diseases, implantation of at least one VBX stent graft as a BSG in one of the target vessels, and clinical or radiologic follow-up of 6 months. The primary end point of the study was technical success of all BSGs, defined as placement of the BSG in the desired position with absence of endoleak on final angiography. Secondary end points were freedom from perioperative major adverse events and freedom from reinterventions and mortality at 6 months. Procedural and postoperative data were analyzed. ResultsBetween December 2017 and July 2018, there were 50 patients (40 male; mean age, 71 years) included. A total of 145 VBX stent grafts were implanted, followed by 57 Advanta V12, 29 Viabahn, and 28 bare-metal stents. There were 126 branches (celiac trunk, 27; superior mesenteric artery, 25; renal arteries, 74) sealed exclusively with VBX. Technical success rate was 98.6%. There were six device-related reinterventions due to type IC endoleaks (n = 4), target vessel stenosis distal to the BSG, and stent graft occlusion in a left renal artery in one case. The perioperative and aneurysm-related mortality was 0%; the 6-month all-cause mortality was 2%. ConclusionsThe used BSGs demonstrated promising preliminary results in F/BEVAR. Further evaluation is mandatory to determine durability of the VBX.