An international, expert-based, Delphi consensus document on controversial issues in the management of abdominal aortic aneurysms.

OBJECTIVE: As a result of conflicting, inadequate or controversial data in the literature, several issues concerning the management of patients with abdominal aortic aneurysms (AAAs) remain unanswered. The aim of this international, expert-based Delphi consensus document was to provide some guidance for clinicians on these controversial topics. METHODS: A three-round Delphi consensus document was produced with 44 experts on 6 prespecified topics regarding the management of AAAs. All answers were provided anonymously. The response rate for each round was 100%. RESULTS: Most participants (42 of 44 [95.4%]) agreed that a minimum case volume per year is essential (or probably essential) for a center to offer open or endovascular AAA repair (EVAR). Furthermore, 33 of 44 (75.0%) believed that AAA screening programs are (probably) still clinically effective and cost effective. Additionally, most panelists (36 of 44 [81.9%]) voted that surveillance after EVAR should be (or should probably be) lifelong. Finally, 35 of 44 participants (79.7%) thought that women smokers should (or should probably/possibly) be considered for screening at 65 years of age, similar to men. No consensus was achieved regarding lowering the threshold for AAA repair and the need for deep venous thrombosis prophylaxis in patients undergoing EVAR. CONCLUSIONS: This expert-based Delphi consensus document provides guidance for clinicians regarding specific unresolved issues. Consensus could not be achieved on some topics, highlighting the need for further research in those areas.

Elective Surgical Repair of Popliteal Artery Aneurysms with Posterior Approach vs. Endovascular Exclusion: Early and Long Term Outcomes of Multicentre PARADE Study.

OBJECTIVE: The aim of this study was compare elective surgical repair of popliteal artery aneurysms (PAAs) via a posterior approach vs. endovascular exclusion, analysing early and five year outcomes in a multicentre retrospective study. METHODS: Between January 2010 and December 2023, a retrospectively maintained dataset of all consecutive asymptomatic PAAs that underwent open repair with posterior approach or endovascular repair in 37 centres was investigated. An aneurysm length of ≤ 60 mm was considered the only inclusion criterion. A total of 605 patients were included; 440 PAAs (72.7%) were treated via a posterior approach (open group) and the remaining 165 PAAs (27.3%) were treated using covered stents (endo group). Continuous data were expressed as median with interquartile range. Thirty day outcomes were assessed and compared. At follow up, primary outcomes were freedom from re-intervention, secondary patency, and amputation free survival. Secondary outcomes were survival and primary patency. Estimated five year outcomes were compared using log rank test. RESULTS: At 30 days, no differences were found in major morbidity, mortality, graft occlusion, or re-interventions. Three patients (0.7%) in the open group experienced nerve injury. The overall median duration of follow up was 32.1 months. At five year follow up, freedom from re-intervention was higher in the open group (82.2% vs. 68.4%; p = .021). No differences were observed in secondary patency (open group 90.7% vs. endo group 85.2%; p = .25) or amputation free survival (open group 99.0% vs. endo group 98.4%; p = .73). A posterior approach was associated with better survival outcomes (84.4% vs. 79.4%; p = .050), and primary patency (79.8% vs. 63.8%; p = .012). CONCLUSION: Early and long term outcomes following elective repair of PAAs measuring ≤ 60 mm via a posterior approach or endovascular exclusion seem comparable. Nerve injury might be a rare but potential complication for those undergoing open surgery. Endovascular repair is associated with more re-interventions.

Cost Analysis of Target Lesion Revascularisation in Patients With Femoropopliteal In Stent Re-Stenosis or Occlusion: The COSTLY-TLR Study.

OBJECTIVE: To report the cost of target lesion revascularisation procedures (TLR) for femoropopliteal peripheral artery disease (PAD) following stenting, from a healthcare payer's perspective. METHODS: European multicentre study involving consecutive patients requiring femoropopliteal TLR (January 2017 - December 2021). The primary outcome was overall cost (euros) associated with a TLR procedure from presentation to discharge. Exact costs per constituent, clinical characteristics, and early outcomes were reported. RESULTS: This study included 482 TLR procedures (retrospectively, 13 hospitals, six countries): 56% were female, mean age was 75 ± 2 years, 61% were Rutherford class 5 or 6, 67% had Tosaka class 3 disease, and 16% had common femoral or iliac involvement. A total of 52% were hybrid procedures and 6% involved open surgery only. Technical success was 70%, 30 day mortality rate was 1%, and the 30 day major amputation rate was 4%. Most costs were for operating time during the TLR (healthcare professionals' salaries, indirect and estate costs), with a mean of: €21 917 ± €2 110 for all procedures; €23 337 ± €8 920 for open procedures; €12 903 ± €3 108 for endovascular procedures; and €22 806 ± €3 977 for hybrid procedures. In a regression analysis, procedure duration was the main parameter associated with higher overall TLR costs (coefficient, 2.77; standard error, 0.88; p < .001). The mean cost per operating minute of TLR (indirect, estate costs, all salaried staff present included) was €177 and the mean cost per night stay in hospital (outside intensive care unit) was €356. The mean cost per overnight intensive care unit stay (minimum of 8 hours per night) was €1 193. CONCLUSION: The main driver of the considerable peri-procedure costs associated with femoropopliteal TLR was procedure time.

Association of Genetic Polymorphisms with Abdominal Aortic Aneurysm in the Processes of Apoptosis, Inflammation, and Cholesterol Metabolism.

Background and Objectives: This study aims to identify the minor allele of the single nucleotide polymorphisms (SNPs) DAB2IP rs7025486, IL6R rs2228145, CDKN2BAS rs10757278, LPA rs3798220, LRP1 rs1466535, and SORT1 rs599839 in order to assess the risk of abdominal aortic aneurysm (AAA) formation and define the linkage among these SNPs. Materials and Methods: A case-control study with AAA patients (AAA group) and non-AAA controls (control group) was carried out in a study population. DNA was isolated from whole blood samples; the SNPs were amplified using PCR and sequenced. Results: In the AAA group of 148 patients, 87.2% of the patients were male, 64.2% had a history of smoking, and 18.2% had relatives with AAA. The mean ± SD of age, BMI, and aneurysmal diameter in the AAA group were 74.8 ± 8.3 years, 27.6 ± 4.6 kg/m2, and 56.2 ± 11.8 mm, respectively. In comparison with 50 non-AAA patients, there was a significantly elevated presence of the SNPs DAB2IP rs7025486[A], CDKN2BAS rs10757278[G], and SORT1 rs599839[G] in the AAA group (p-values 0.040, 0.024, 0.035, respectively), while LPA rs3798220[C] was significantly higher in the control group (p = 0.049). A haplotype investigation showed that the SNPs DAB2IP, CDKN2BAS, and IL6R rs2228145[C] were significantly elevated in the AAA group (p = 0.037, 0.037, and 0.046) with minor allele frequencies (MAF) of 25.5%, 10.6%, and 15.4%, respectively. Only DAB2IP and CDKN2BAS showed significantly higher occurrences of a mutation (p = 0.028 and 0.047). Except for LPA, all SNPs were associated with a large aortic diameter in AAA (p < 0.001). Linkage disequilibrium detection showed that LPA to DAB2IP, to IL6R, to CDKN2BAS, and to LRP1 rs1466535[T] had D' values of 70.9%, 80.4%, 100%, and 100%, respectively. IL6R to LRP1 and to SORT1 had values for the coefficient of determination (r2) of 3.9% and 2.2%, respectively. Conclusions: In the investigated study population, the SNPs CDKN2BAS rs10757278, LPA rs3798220, SORT1 rs599839, DAB2IP rs7025486, and IL6R rs2228145 were associated with the development of abdominal aortic aneurysms. Individuals with risk factors for atherosclerosis and/or a family history of AAA should be evaluated using genetic analysis.

The Effect of EndoAnchors on Aneurysm Sac Regression for Patients Treated With Infrarenal Endovascular Repair With Hostile Neck Anatomies: A Propensity Scored Analysis.

PURPOSE: To analyze sac evolution patterns in matched patients with hostile neck anatomy (HNA) treated with standard endovascular aneurysm repair (sEVAR) and endosutured aneurysm repair (ESAR). METHODS: Observational retrospective study using prospectively collected data between June 2010 and December 2019. ESAR group data were extracted from the primary arm of the PERU registry with an assigned identifier (NCT04100499) at 8 centers and those from the sEVAR came from 4 centers. Suitability for inclusion required: no proximal endograft adjuncts (besides EndoAnchor use), ≤15 mm neck length and minimum of 12-months follow-up imaging. Bubble-shaped neck (noncylindrical short neck with discontinuous seal) aspect was analyzed. Both groups were analyzed using propensity score matching (PSM) for aortic neck length, width, angulation, and device fixation type. Main outcome assessed was sac evolution patterns (sac expansion and regression were defined as >5mm increase or decrease, of the maximum sac diameter respectively; all AAAs within this ±5 mm range in diameter change were considered stable) and secondary outcomes were type-Ia endoleaks; other endoleaks and mortality. A power analysis calculation >80% was confirmed for sac regression evaluation. RESULTS: After exclusions, PSM resulted in 96 ESAR and 96 sEVAR patients. Mean imaging follow-up (months) was 44.4±21.3 versus 43.0±19.6 (p=0.643), respectively. The overall number of patients achieving sac regression was higher in the ESAR group (n=57, 59.4% vs n=31, 32.3%; p<0.001) and the cumulative sac regression achieved at 5 years was 65% versus 38% (p=0.003) in favor of the ESAR group. There were no statistically significant differences in type-Ia endoleak and/or other endoleaks. Univariate analysis for sac regression patients in the sEVAR and ESAR group individually showed the bubble-shape neck as a predictor of sac regression failure. There were no statistical differences in overall and aneurysm-related mortality. CONCLUSION: Endosutured aneurysm repair provided improved rates of sac regression for patients with AAA and HNA when compared with sEVAR at midterm and up to 5 years, despite similar rates of type-Ia endoleaks, and the need to consider some important limitations. The presence of bubble-shaped neck was a predictor of sac regression failure for both groups equally. CLINICAL IMPACT: The use of EndoAnchors aids and improves EVAR treatment in hostile neck anatomies by an increased rate of sac regression when compared to EVAR treatment alone in up to 5 year analysis. Moreover, a trend to reduced number of type Ia endoleaks is also achieved, although not significant in the present study. This data, adds to current and growing evidence on the usefulness of EndoAnchors for AAA endovascular treatment.

Long-term Results of Thoracic Endovascular Aortic Repair Using a Low-Profile Stent-Graft.

PURPOSE: To evaluate the long-term results associated with the Zenith Alpha thoracic stent-graft, which was designed to address challenging access vessel anatomy. MATERIALS AND METHODS: A retrospective analysis was conducted of 44 consecutive patients (mean age 72.5±8.3 years; 25 men) treated in a single center between August 2010 and October 2014 with a minimum follow-up of 5 years in survivors. The Zenith Alpha thoracic stent-graft was used to treat thoracic aortic aneurysms (n=37), thoracoabdominal aortic aneurysm (n=5), or penetrating aortic ulcer (n=2). Ten patients (23%) were American Society of Anesthesiologists class IV, and 9 (20%) had nonelective procedures. Access vessel anatomy was demanding (mean minimum diameter 5.4 mm, tortuosity index 1.3). The primary endpoint at 5 years was ongoing clinical success (freedom from aneurysm-/procedure-related death, secondary intervention, type I or III endoleak, infection, thrombosis, aneurysm expansion, rupture, or conversion). Secondary endpoints were freedom from all-cause mortality, device migration, stent fractures, fabric erosions, endoleaks, neurological events, and access vessel complications. RESULTS: The ongoing clinical success was 84% (37 of 44 patients) owing to 4 aneurysm-related deaths (9%), 3 type I or III endoleaks (1 in a deceased patient), and 1 aneurysm expansion without detectable endoleak. There were 3 access vessel complications (7%), and no postoperative neurological events. Migration was observed in 2 cases (5%). There were no stent fractures or fabric tears. CONCLUSION: Despite the alterations in stent-graft design and material to reduce profile, the Zenith Alpha thoracic stent-graft showed favorable long-term results even in multimorbid patients with demanding iliac anatomy.

Performance of the Gore VBX Balloon Expandable Endoprosthesis as Bridging Stent-Graft in Branched Endovascular Aortic Repair for Thoracoabdominal Aneurysms.

PURPOSE: Bridging stent stability is crucial for efficacy and safety of branched aortic endovascular repair (bEVAR) of thoracoabdominal aortic aneurysms (TAAAs). In this study, we assess the performance of the new Viabahn Balloon-Expandable endoprosthesis (VBX) in bEVAR. Based on our learning curve we give recommendations for a safe and effective use of the device. MATERIALS AND METHODS: We prospectively collected the data of patients with TAAAs undergoing bEVAR between December 2017 and December 2019. All patients with implantation of at least 1 VBX stent-graft as bridging stent were included in our single-center analysis. Demographic, comorbidity, and computed tomography angiography (CTA) data of 112 patients were retrospectively evaluated. Primary endpoint was a composite of branch-related technical success and freedom from target vessel instability. Secondary endpoints were clinical and ongoing clinical success. RESULTS: Primary endpoint: technical success was achieved in all patients (100%) with a freedom from target vessel instability of 96.3% after a median follow-up of 18 months. Overall mortality was 13.4% (n=15) and 13 patients underwent secondary interventions, 12 of them are still alive and 1 suffered from aneurysm sac expansion, consequently an ongoing clinical success of 75.9% was reached. After modification of the implantation technique during the course of the study by selecting longer stent lengths after accurate estimation of vessel curvature and expected adaptation of the flexible endoskeleton to the specific anatomical conditions, no type Ic endoleaks were observed in the last 70 cases. CONCLUSIONS: The VBX stent-graft can be safely used as bridging stent for branched thoracoabdominal repair. However, learning curve should be considered to avoid type Ic endoleak and edge stenosis. Based on this experience longer landing zones and 2-step deployment of VBX are useful for successful bridging also of challenging target vessels.

Treatment of iliac atherosclerotic lesions using the balloon-expandable dynamic bare metal stent: One-year outcomes of the BIODYNAMIC single-center retrospective analysis.

OBJECTIVES: Endovascular therapy using balloon expandable stents has become the treatment standard for most iliac atherosclerotic lesions. We aimed to assess the safety and performance of the Dynamic stainless-steel balloon-expanding stent system in this location. METHODS: BIODYNAMIC is a retrospective single center study including consecutive patients with iliac lesions treated with the Dynamic stent system. Not included were implantations inside an endograft. The primary endpoint was freedom from major adverse limb events (MALE) at 12 months, defined as index limb amputation or target lesion revascularization (TLR). Secondary endpoints were procedure success, ankle brachial index (ABI) and Rutherford class change, mortality and freedom from TLR after 12 months. RESULTS: Within two years, 182 patients with 234 lesions in the common iliac artery were enrolled. Rutherford class 5 and 6 were present in 11.5% of patients, average stent diameter was 8.0 ± 0.5 mm and stented length 40.0 ± 15.3 mm. The primary endpoint was reached in 96.2% (225/234) of the cases, with six TLR (2.6%) and three target limb amputations (1.3%). Procedure success was obtained in all but three patients (98.4%). In paired analysis, ABI improved by 0.25 ± 0.21 from baseline to 0.90 ± 0.16 post-procedure and Rutherford class improved by -1.75 ± 1.53. There were four non-device-related deaths (2.2%). Freedom from TLR was 97%, 95.3%, 94% and 92.7% at 24, 36, 48 and 60 months, respectively. CONCLUSION: The Dynamic balloon-expandable stent system proved to be safe and effective in a population with common iliac artery lesions.

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

OBJECTIVE: Until 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. METHODS: Retrospective 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. RESULTS: Between 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%. CONCLUSIONS: The used BSGs demonstrated promising preliminary results in F/BEVAR. Further evaluation is mandatory to determine durability of the VBX.

Comparative in vitro activity of bacteriophage endolysin HY-133 against Staphylococcus aureus attached to vascular graft surface.

Novel strategies are needed for combating Staphylococcus aureus biofilm in vascular graft infections. We investigated the in vitro activity of bacteriophage endolysin HY-133, daptomycin and rifampin against S. aureus attached to vascular graft surface. Daptomycin showed rapid bactericidal effect on surface-associated S. aureus, while the activity of HY-133 on graft surface-adherent cells was moderate and rifampin did not achieve bactericidal effect. Even in the highest concentrations, all antimicrobials used failed in a complete eradication of the surface-adherent bacteria.

Comparison of the Biomechanical Properties of the Advanta V12/iCast and Viabahn Stent-Grafts as Bridging Devices in Fenestrated Endografts: An In Vitro Study.

Purpose: To compare experimentally the biomechanical properties of the Viabahn Balloon-Expandable Stent Graft (VBX) with the widely used Advanta V12/iCast in the role of bridging stent-grafts for fenestrated endovascular aortic repair. Materials and Methods: Test sheets made of polyester having 2 rows of 5 fenestrations in 6-mm and 8-mm diameters were used to simulate a commercially made fenestrated aortic endograft. In total, 40 stent-grafts measuring 6×39 mm and 8×39 mm (10 of each size for each stent-graft) were implanted in fenestration sheets immersed in a 37°C water bath. After flaring, all stent-grafts were evaluated using microscopy and radiography. Biomechanical evaluation included pullout and the shear stress force testing; results are reported in Newtons (N) as the median (minimum-maximum). Results: After flaring, no damage or fracture to the stent-graft structures were detected. Pullout forces for the 6-mm stent-grafts were 27.1 N (20.0-28.9) for the VBX and 16.6 N (14.7-19.2) for the Advanta (p=0.008). Pullout forces for the 8-mm stent-grafts were 20.1 N (14.8-21.5) for the VBX and 15.8 N (12.4-17.5) for the Advanta (p=0.095). The shear stress forces necessary to dislocate the device at 150% stent diameter displacement was 12.5 N (VBX) vs 14.7 N (Advanta) for the 6-mm devices and 23.3 N (VBX) vs 20.2 N (Advanta) for the 8-mm stents (p>0.99 and p=0.222, respectively). Conclusion: In vitro tests simulating external pull and shear forces on bridging stent-grafts implanted in fenestrations showed that the VBX had resistance to dislocation equivalent to a well-known control device.

One-Year Results From the SURPASS Observational Registry of the CTAG Stent-Graft With the Active Control System.

Purpose: To report the outcomes from the observational SURPASS registry, which was created to assess the performance of the Conformable TAG (CTAG) stent-graft with the Active Control System (ACS) in patients undergoing thoracic endovascular aortic repair (TEVAR) in a real-world setting. Materials and Methods: The SURPASS registry (ClinicalTrials.gov; identifier NCT03286400) was an observational, prospective, single-arm, post-market, international study that enrolled patients undergoing TEVAR using the CTAG with ACS for both acute and chronic thoracic aortic disease between October 2017 and July 2018. The CTAG with ACS features 2-stage deployment of the stent-graft and an optional angulation mechanism that modifies only the proximal end of the stent-graft. During the observation period, 127 patients (mean age 67.1±12.1 years, range 27-86; 92 men) were enrolled and treated for an array of aortic pathologies, including chronic and acute lesions and 4 ruptured descending thoracic aneurysms. The primary outcome of this study was technical success; secondary outcomes were clinical success and major adverse events at 30 days and 12 months. The numbers of 2-stage device deployments and applications of the angulation mechanism were recorded, along with the reasons for use. Results: Technical success of the TEVAR was 97.6% owing to unintentional partial coverage of supra-aortic branches in 3 cases (the vessels were patent on imaging). The stent-graft was repositioned at its intermediate diameter in 79 patients (62.2%), and the angulation feature was applied in 64 cases (50.4%), mainly to improve proximal wall apposition and orthogonality in the aorta. The desired effect was achieved in 60 cases (93.8%). There was no device compression, bird-beak configuration, fracture, or graft occlusion. The 30-day and 12-month clinical success rates were 97.6% and 92.9%, respectively. There were 3 aorta-related deaths at 30 days and a further 3 at 12 months. Fatalities were due to a retrograde type A dissection (0.8%), paraplegia, bowel ischemia, sepsis in the setting of a mycotic aneurysm, aneurysm rupture post aortoesophageal fistula, and multiorgan dysfunction syndrome. Three endoleaks (2 type Ia and 1 type III) required reintervention. Conclusion: In the SURPASS registry, the use of the CTAG device with ACS showed promising outcomes despite the challenging pathologies. The new delivery system enables a controlled staged delivery with in situ adjustments during positioning, facilitating the treatment of complex aortic disease.

Multicenter experience with endovascular treatment of aortic coarctation in adults.

OBJECTIVE: The objective of this study was to evaluate outcomes of endovascular treatment of aortic coarctation in adults. METHODS: Clinical data and imaging studies of 93 consecutive patients treated at nine institutions from 1999 to 2015 were reviewed. We included newly diagnosed aortic coarctation (NCO), recurrent coarctation, and aneurysmal/pseudoaneurysmal degeneration (ANE) after prior open surgical repair (OSR) of coarctation. Primary end points were morbidity and mortality. Secondary end points were stent patency and freedom from reintervention. RESULTS: There were 54 (58%) male and 39 (42%) female patients with a mean age of 44 ± 17 years. Thirty-two patients had NCO (mean age, 48 ± 16 years) and 61 had endovascular reinterventions after prior OSR during childhood (mean, 30 ± 17 years after initial repair), including 50 patients (54%) with recurrent coarctation and 11 (12%) with ANE. Clinical presentation included asymptomatic in 31 patients (33%), difficult to control hypertension in 42 (45%), and lower extremity claudication in 20 (22%). Endovascular treatment was performed using balloon-expandable covered stents in 47 (51%) patients, stent grafts in 36 (39%) patients, balloon-expandable uncovered stents in 9 (10%) patients, and primary angioplasty in 1 (1%) patient. Mean lesion length and diameter were 64.5 ± 50.6 mm and 19.5 ± 6.7 mm, respectively. Mean systolic pressure gradient decreased from 24.0 ± 17.5 mm Hg to 4.4 ± 7.4 mm Hg after treatment (P < .001). Complications occurred in nine (10%) patients, including aortic dissections in three (3%) patients and intraoperative ruptures in two patients; type IA endoleak, renal embolus, spinal headache, and access site hemorrhage occurred in one patient each. The aortic dissections and ruptures were treated successfully by deploying an additional covered stent proximal to the site of dissection or rupture. Two patients died within 30 days of the index procedure. After a mean follow-up of 3.2 ± 3.1 years, nearly all patients (98%) were clinically improved and all stents were patent. Reintervention was needed in 10 (11%) patients. Freedom from reintervention at 5 years was 85%. Two additional patients died during follow-up of coarctation-related causes, including rupture of an infected graft and visceral ischemia. Patient survival at 5 years was 89%. CONCLUSIONS: Endovascular repair is effective with an acceptable safety profile in the treatment of NCO and postsurgical complications of coarctation after initial OSR. Aortic rupture is an infrequent (2%) but devastating complication with high mortality. Balloon-expandable covered stents are preferred for NCO, whereas stent grafts are used for ANE. The rate of reinterventions is acceptable, with high procedural and long-term clinical success.

In Vitro Evaluation of the Gore Viabahn Balloon-Expandable Stent-Graft for Fenestrated Endovascular Aortic Repair.

PURPOSE: To evaluate the safety and integrity of a new stent-graft as a potential bridging device in fenestrated stent-grafts using an in vitro fenestrated model. MATERIALS AND METHODS: Polyester test sheets with ten 6-mm- or 8-mm-diameter fenestrations were used to simulate a fenestrated main body endoprosthesis. In total, 50 Viabahn balloon-expandable (VBX) stent-grafts of varying lengths (29 and 39 mm) and diameters (6, 7, and 8 mm) were implanted in the fitting fenestrations. After release, the 6- and 7-mm-diameter stent-grafts were flared with a 10×20-mm angioplasty balloon; a 12×20-mm balloon was used in the 8-mm-diameter devices. Safety of the devices was defined as absence of fractures detected on radiography or computed tomography (CT), as well as material failure detected by microscopy and water permeability testing. The forces (in Newtons, N) needed for perpendicular dislocation (pullout force) and axial dislocation (shear stress force) were also evaluated. RESULTS: Forty VBX stent-grafts were subjected to digital radiographic imaging and multiplanar CT. None showed any stent fracture. Subsequent microscopy indicated no damage to the fabric or separation of the graft after flaring. Ten VBX stent-grafts underwent water permeability testing after flaring; no water passed through the graft wall during a 10-minute period under an intraluminal pressure at 120 mm Hg. Testing of 25 VBX stent-grafts revealed initial pullout forces between 11.3 and 31 N. Shear stress tests showed that the average force needed to dislocate the stent-grafts by 50% of their diameter ranged between 5.75 and 6.91 N (mean 6.1±0.5 N) for the 6-mm stents and between 3.31 and 5.4 N (mean 4.4±0.8) for the 8-mm stents. CONCLUSION: This preliminary study demonstrated the applicability of the VBX as a bridging stent-graft in a simulated fenestration model. A comparison with other stent-grafts and clinical assessment are required.

Performance of BeGraft and BeGraft+ Stent-Grafts as Bridging Devices for Fenestrated Endovascular Aneurysm Repair: An In Vitro Study.

Purpose: To investigate 2 generations of balloon-expandable covered stents as potential bridging devices using an in vitro model of stent-graft fenestrations. Materials and Methods: Twenty BeGraft and 20 BeGraft+ cobalt-chromium stents covered in expanded polytetrafluoroethylene (ePTFE) in 6- and 8-mm diameters were tested in sheets mimicking stent-graft fenestrations. Microscopy and radiography were employed to evaluate stent morphology after flaring. In vitro bench tests measured maximum pullout (perpendicular displacement) and the shear stress (axial displacement) forces needed to dislocate the stents. Results: No alteration of ePTFE coverage was detected in the flared stents. Digital radiography and computed tomography showed marked alteration of the stent geometry, which was more pronounced in the BeGraft group. No fractures were detected. Median (minimum-maximum) pullout forces for the 6-mm stent-grafts were 17.1 N (15.8-19.6) for the BeGraft device and 30.4 N (20.2-31.9) for the BeGraft+ device (p=0.006). Median (minimum-maximum) pullout forces for the 8-mm stent-grafts were 11.3 N (11-12.1) for the BeGraft device and 21.8 N (18.2-25.5) for the BeGraft+ device (p<0.001). The shear stress test showed median forces of 10.5 vs 15.28 N at 150% of the stent diameter for the 6-mm BeGraft and BeGraft+ stent-grafts, respectively, and 15.23 vs 20.72 N at 150% stent diameter for the 8-mm models (p=0.016 and 0.017, respectively). Conclusion: Flaring changed the stent geometry but did not provoke stent fractures. The BeGraft+ is superior to the BeGraft in terms of pullout and shear stress forces, demonstrating greater resilience.

In Vitro Evaluation of Balloon-Expandable Chimney Grafts in the Renal Arteries Combined With the Endurant Endograft.

Purpose: To compare balloon-expandable covered stents (BECS) available for use as renal chimney grafts to the Advanta V12 approved for use with the Endurant endograft. Materials and Methods: A silicone model was manufactured based on preoperative computed tomography angiography (CTA) scans of a patient with a 7-cm juxtarenal aneurysm treated with an Endurant bifurcated endograft and an Advanta V12 covered stent for the 6-mm-diameter right renal artery. The model was placed in a flow box filled with a 37°C blood-mimicking solution equipped with a pulsatile pumping system (140/60 mm Hg). The tested BECS were the Advanta V12, the VBX, and the BeGraft+. A 36-mm-diameter Endurant II endograft with a 16-mm-diameter contralateral limb and a 6×59-mm BECS chimney graft were used in 9 consecutive tests (3 for each combination). After each implantation, the model was placed in the CT scanner, and 2 radiologists blinded to the test device independently measured the gutter areas and the patent chimney graft lumen at the level of the Endurant's suprarenal stent, at the level of the chimney's maximum curvature, and 10 mm inside the renal artery. The intraclass correlation coefficients (ICC) were calculated to assess interreader reliability. Results: The mean gutter areas were 19.3±7, 20.2±8, and 22.3±8 mm2 for the Advanta, VBX, and BeGraft+, respectively (all p>0.05). At the level of the aortic endograft's suprarenal stent struts, the mean diameter of the Advanta V12, VBX, and BeGraft+ were 4.46±0.3, 4.12±0.4, and 4.12±0.3 mm, respectively (all p>0.05). At the level of the maximum chimney graft angulation, the mean diameters were 3.77±0.3, 4.16±0.1, and 3.74±0.3 mm, respectively (all p>0.05). In the right renal artery, the mean diameters were 3.91±0.2, 4.05±0.9, and 4.3±0.4 mm, respectively (all p>0.05). The ICCs varied between 0.7 and 0.9, indicating good agreement between readers. Conclusion: These in vitro findings showed comparable results between the Advanta V12 and the available BECS used in conjunction with the Endurant endograft according to the instructions for use. Further clinical evaluation is needed to confirm these results.

Outcomes of Surgical Explantation of Infected Aortic Grafts After Endovascular and Open Abdominal Aneurysm Repair.

OBJECTIVES: Infection of the vascular graft represents one of the most threatening complications after aortic repair. It is rare and associated with high morbidity and mortality rates. The aim of this study was to present short-term outcomes after surgical treatment of infected aortic grafts after endovascular and open repair of abdominal aortic aneurysms (AAAs). METHODS: Data of all patients affected by aortic graft infection after aneurysm repair who underwent an explantation of a conventional or endovascular aortic graft between January 2008 and December 2016 were retrospectively reviewed. All patients underwent in situ reconstruction using a rifampicin soaked synthetic graft. The primary endpoint of this study was 30 day mortality; secondary endpoints were major post-operative complications. RESULTS: Twenty-six patients were included in the cohort, 16 with an infected endograft (iEVAR) and 10 patients with an infected conventional graft (iOAR). Thirty-day mortality was 23.1% overall, 37.5% for iEVAR and 0% (p = .027) for iOAR. Post-operative major complications occurred in eight (50%) patients from the iEVAR group and in four (40%) patients from the iOAR group (p = .619). The supravisceral clamping rate was higher in patients with infected iEVAR (93.8 vs. 20%, p = .001), furthermore a greater incidence of post-operative acute kidney injury was observed (50 vs. 0%, p = .009). CONCLUSIONS: Explantation of the graft and in situ reconstruction for aortic graft infection is accepted as the therapy of choice. However, re-operation for iEVAR is related to significantly higher mortality and morbidity rates. The need for suprarenal aortic clamping seems to be a possible explanation for worse outcomes in iEVAR.

Impact of aortic stent-graft oversizing on outcomes of the chimney endovascular technique based on a new analysis of the PERICLES Registry.

OBJECTIVE: Chimney endovascular aortic aneurysm repair is gaining ever greater acceptance. However, persistent gutters leading to type IA endoleaks represent an unsolved issue. The aim of the current study was to analyze the impact of abdominal endograft oversizing to the occurrence of this phenomenon. METHODS: The PERformance of the snorkel/chImney endovascular teChnique in the treatment of compLex aortic PathologiesES registry includes the largest experience with chimney endovascular aortic aneurysm repair from 13 vascular centers in Europe and the U.S. Prospectively collected data from centers with standard use of the Endurant stent-graft and balloon-expandable covered stents as chimney grafts only were included in the present analysis. The parameter which varied was the degree of oversizing of the aortic stent-graft classifying the cohort in two groups, group A (20% and less oversizing) and group B (>20% of oversizing). The primary endpoint was the incidence of persistent type IA endoleak needed reintervention. Secondary endpoints were all-cause mortality and freedom from reintervention. RESULTS: Group A included 21 patients while group B 144. The mean preoperative pathology's neck length and diameter was 5.8 mm (±4.4) versus 4.9 mm (±3.8) and 27.6 mm (±4.7) versus 24.9 mm (±3.7) for group A and group B, respectively. The mean length of the new sealing zone after chimney graft placement was similar for both groups (group A versus group B; 17.9 mm versus 18.3 mm, respectively, P = .21). The percentage of oversizing of the aortic stent-graft ranged between 13.8 and 20% versus 22.2 and 30%, for group A and group B, respectively. Patients of group A had more type 1A endoleaks, (14.3%) versus patients of group B (2.1%) based on the first follow-up imaging, P = .02. The incidence of persistent type IA endoleaks needing a reintervention was 14.3 and 1.4% for the group A and group B, respectively, P = .01. The mean volume of contrast medium used was greater in group A versus group B with 239 ml versus150 ml, P = .05. Additionally, 14.3% of patients of group A experienced acute renal failure compared to those in group B which was 1.0%, P = .01. CONCLUSIONS: Oversizing of ideally 30% of the Endurant stent-graft is associated with significant lower incidence of type IA endoleaks requiring reintervention for patients treated by chimney endovascular aortic aneurysm repair.

Durability of a low-profile stent graft for thoracic endovascular aneurysm repair.

OBJECTIVE: The introduction of lower profile endografts expanded the application of aortic endovascular repair. However, evidence about their durability is still scarce. The objective of this study was to assess longer term durability of the Zenith Alpha Thoracic Stent Graft (Cook Inc, Bloomington, Ind) after thoracic endovascular aortic repair. METHODS: Prospectively collected data of all patients treated for thoracic aortic aneurysms or penetrating aortic ulcers and having computed tomography angiography-based follow-up of ≥12 months were retrospectively analyzed. The primary end point was ongoing clinical success. Among the secondary end points, stent graft migration and fracture were analyzed. RESULTS: Between August 2010 and October 2015, 70 consecutive patients were treated in a single center with the Zenith Alpha stent graft. With computed tomography angiography-based follow-up of 22.3 ± 15.9 months, ongoing clinical success was 87.1%. There were three cases of type IA endoleak (4.3%), two cases of type IB endoleak (2.9%), and one case of aneurysm sac enlargement (1.4%). Five patients died postoperatively (7.1%). No type III or type IV endoleak was detected; there was one case of distal stent graft migration and no stent fracture. Reintervention was necessary in one case (1.4%) of a combined type IA and type II endoleak. There were no conversions to open repair and no ruptures or intraoperative deaths. All-cause mortality was 17.1% at 76 months. CONCLUSIONS: The Zenith Alpha Thoracic Stent Graft appears to maintain favorable results in a longer time frame with a low incidence of aneurysm sac growth and migration. Results from multicenter prospective trials are needed to validate these data.

Postmarket Clinical Experience with the INCRAFT AAA Stent Graft System for Challenging Access Routes.

BACKGROUND: The INCRAFT system is a new device that has become available in Europe in September 2014 after the announcement of the 2-year results of the INNOVATION trial. However, no data in the "real-world" practice exist. Herein, we report our early series of consecutive patients treated with the INCRAFT after its launch on the market. METHODS: Prospectively collected data of patients enrolled in the INNOVATION trial (group IT) and consecutive patients from CE Mark approval to April 2015 (group CM) were retrospectively evaluated and compared. Main outcomes were any device- or procedure-related major adverse event (MAE) within 30 days and survival and reinterventions during follow-up. RESULTS: Seventeen patients were included in group IT (median follow-up [95% CI]; 60.4 months [55-63]), and 24 patients were in group CM (12.5 [6.6-13.5]). The patients' comorbidities were comparable between the groups. The average diameter of aortic bifurcation and the bilateral external iliac arteries was significantly smaller in group CM. Adjunctive interventions for iliac artery disease were performed in 8 patients (33%) in group CM, whereas no adjunctive was required in group IT. MAEs within 30 days were not significantly different between 2 groups. Survival and reintervention rates were also equivalent after a median follow-up of 13 months. CONCLUSIONS: Compared to our patients recruited for the INNOVATION trial, the patients after CE Mark approval had significantly more challenging access routes reflecting the difficulties of "real-world" conditions. Despite frequent adjunctive procedures in group CM, the early performance of the endograft was encouraging so far. Long-term surveillance of those patients remains mandatory.