Limb Graft Occlusion Research Articles

Bare metal stent application to prevent limb occlusion in iliac arteries with severe tortuosity during an endovascular aneurysm repair: a cohort study.

The risk of limb graft occlusion (LGO) after endovascular aneurysm repair (EVAR) is increased by severe tortuosity of the iliac artery. A bare metal stent (BMS) may protect LGO, according to the hypothesis of this single-center retrospective analysis. All patients undergoing elective EVAR with a bifurcated stent graft between January 2012 and June 2022 were included in this cohort study. Patients demonstrating significant tortuosity at the iliac angle were incorporated into this study and classified into two groups: group A comprised those who received a BMS. In contrast, group B consisted of those who did not receive a BMS. The primary outcomes were the incidence of limb occlusion and technical success during the follow-up period. However, secondary outcomes included perioperative mortality, external iliac angioplasty, and crossed-limb techniques. This study has been reported as being in line with the STROCSS criteria. A total of 157 patients (mean age = 71.6 ± 8 years) with infrarenal abdominal aortic aneurysms were enrolled. In total, 50 individuals were included in group A, while 107 were in group B. Overall technical success was 100%, and only one (2%) patient from group A and 17 (15%) from group B suffered from limb occlusion during follow-up (p < 0.05). At a mean follow-up imaging duration of 28.7 ± 23.6 months (range 1-124), the estimated primary limb patency at 2 years was 98% for the BMS group and 84% for the non-BMS group (p < 0.05). There were no changes in perioperative mortality or crossed-limb procedures between the BMS and non-BMS groups. Nonetheless, there were disparities in external iliac angioplasty between the two groups during the follow-up period (p < 0.05). Deploying a BMS inside the iliac artery to prevent or treat limb occlusion is a safe and effective strategy, with clear prolonged outcomes concerning patency and re-interventions.

The Enzen Trial: Analysis of EVAR Endoprosthesis Zenith and Endurant for Infrarenal Aortoiliac Aneurysms Regarding Outcomes, Endoleaks, and Reinterventions.

The main objective of this paper is to analyze the outcomes regarding endoleaks, reinterventions, and death related to aneurysm complications in patients submitted to endovascular repair (EVAR) for abdominal aortoiliac aneurysm (AAA) using Endurant II (Medtronic) and Zenith Flex (Cook) endografts. This was a prospective, consecutive cohort study of patients with AAA who underwent EVAR between January 2019 and December 2022. Two groups of patients were evaluated: Group Endurant (patients submitted to EVAR with the use of Endurant II) and Group Zenith (patients submitted to EVAR with the use of Zenith Flex). A total of 156 patients were evaluated. Group Zenith (67 patients, 42.9%) and Group Endurant (89 patients, 57.1%). The perioperative mortality was 5.1%, eight patients (six patients Group Zenith, and two patients Group Endurant, p=0.054). There were 28 patients (17.9%) submitted to urgent repair of the aneurysm (expansion or rupture), with no differences among the groups. There were 36 cases (23.1%) of later endoleak, with a higher incidence in Zenith group (23 patients, 34.3%) than Endurant group (13 patients, 14.6%, p=0.002), most of them Type II endoleak (21 patients, 13.4%). There were 12 cases of Type I endoleak, also with a higher prevalence in Zenith group (13.4%) than Endurant group (3.4%, p=0.002). Moreover, regarding limb graft occlusion (LGO), there were nine patients (5.8%), with a higher prevalence in Zenith group (9%) than Endurant group (3.4%, p=0.045). The overall survival in a Kaplan-Meier at 720 days was 82.3% in the Zenith group and 89.1% in the Endurant group, with no statistical significance among the groups (p=0.09). The freedom from reintervention rates in a Kaplan-Meier at 720 days was 82.8% in the Zenith group and 93.2% in the Endurant group (p=0.001). In this present study, Zenith endograft had higher rates of endoleaks, aneurysms related mortality, LGO and reinterventions than patients submitted to Endurant II endografts. The linear regression analysis showed that the presence of endoleaks, type of endograft device (Zenith graft) and limb graft occlusion were related to higher reintervention rates. In this present study, Zenith endograft had higher rates of endoleaks, aneurysms related mortality, limb graft occlusions and reinterventions than patients submitted to Endurant II endografts. The main impact and the innovation that this article provides is an opportunity to evaluate and choose the best endograft suitable for the patient with AAA during EVAR.

Endovascular repair for infra-renal aortic aneurysms with supra-renal fixation endoprosthesis: Results and outcomes.

The main objective of this paper is to evaluate the outcomes regarding endoleaks, reinterventions, and death related to aneurysm complications in patients submitted to endovascular repair (EVAR) for abdominal aortoiliac aneurysm (AAA) using Endurant II (Medtronic) and Zenith Flex (Cook) endografts. This was a prospective, consecutive cohort study of patients with AAA who underwent EVAR with the use of Endurant II stent graft and Zenith Flex endograft. A total of 156 patients submitted to EVAR were evaluated. The perioperative mortality was 5.1%, 8 patients. The median clinical follow-up period was 760 ± 80 days. There were 28 patients (17.9%) submitted to urgent repair of the aneurysm (symptomatic expansion or rupture) and 128 patients (82.1%) submitted to elective repair. There were 36 cases (23.1%) of later endoleak and most of them are Type II endoleaks (21 patients, 13.4%). There were 12 cases of Type I endoleak. Moreover, regarding limb graft occlusion (LGO), there were 9 patients (5.8%). The overall survival rate in Kaplan-Meier analysis at 720 days was 84.8% in the total cohort. The freedom from reintervention rate in Kaplan-Meier analysis at 720 days was 92.7% in the total cohort. The linear regression analysis for survival rates showed that chronic kidney disease (p = .03; hazard ratio (HR) = 2.82, CI = 1.07-4.44) was the only factor related to poorer survival rates in both univariate and multivariate analyses. The linear regression analysis showed that the presence of endoleaks (p < .001, HR = 6.69, CI = 2.26-8.48) and limb graft occlusion (p < .001, HR = 8.02, CI = 1.60-9.99) were related to reintervention in both univariate and multivariate analyses. In this present study, supra-renal fixation endograft devices were safe and efficient in treating AAA, with satisfactory results and no renal compromise. The linear regression analysis showed that the presence of endoleaks and limb graft occlusion were related to higher reintervention rates in both univariate and multivariate analyses.

Cook Zenith Alpha Endograft: A Protocol to Minimise Limb Graft Occlusion

Numerous articles have reported an increased incidence of limb graft occlusion (LGO) with the Cook Zenith Alpha endograft compared with other endografts in endovascular aortic aneurysm repair (EVAR). The present study aimed to assess the rate of LGO after EVAR in particular with the Cook Zenith Alpha device when adhering to a standardised protocol designed to prevent limb related complications. This was a non-sponsored retrospective study performed in two university vascular surgery centres employing the same protocol for limb complication prevention during EVAR from 2016 to 2019. The protocol encompassed: (1) angioplasty of any common or external iliac artery with > 50% stenosis before endograft navigation; (2) proximal sealing zone of limbs at the same level of the flow divider with minimum overlap, which is more restrictive than the Cook Zenith Alpha instructions for use; (3) semi-compliant kissing ballooning of limbs; (4) limb stenting for any residual tortuosity, kinking, or stenosis; and (5) adjunctive common and external iliac stenting for residual stenosis or dissection after EVAR. Patients enrolled in this study were treated with standard aortobi-iliac EVAR. Follow up was performed by clinical visit and duplex ultrasonography at discharge, six months, and yearly thereafter. The primary endpoint was to evaluate the LGO rate with different EVAR devices (Cook Zenith Alpha, Gore C3, and Medtronic Endurant) and to determine potential risk factors for LGO associated with the Zenith Alpha. In the study period, 547 EVARs were considered: 233 (42.6%) Cook Zenith Alpha, 196 (35.8%) Gore Excluder,and 118 (21.6%) Medtronic Endurant. The mean follow up was 44 ± 23 months, and the five year freedom from LGO was 97 ± 3%, without differences between groups (97 ± 2%, 95 ± 3%, and 100% with Cook Zenith Alpha, Medtronic Endurant, and Gore Excluder, respectively; p= .080). In the Zenith Alpha group, intra-operative adjunctive iliac artery angioplasty, iliac artery stenting, or iliac limb stenting was performed in 8%, 3.4%, and 9.7% of cases, respectively. Analysis of potential risk factors for LGO identified external iliac artery distal landing and large main bodies (ZIMB 32 - 36) to be independently associated with LGO during follow up (hazard ratio [HR] 18, 95% confidence interval [CI] 3 - 130, p= .004; and HR 12, 95% CI 1.2 - 130, p= .030, respectively). The present experience with a protocol for limb complication prevention allows achievement of a low rate of LGO at five years with Zenith Alpha endografts similar to other endografts. Specific risk factors for the Cook Zenith Alpha endograft are external iliac artery distal landing and the use of a large main body (ZIMB 32 - 36).

Early Clinical Results From the Japanese Prospective Multicenter Study to Evaluate Zenith Alpha Abdominal Stent Graft for Abdominal Aortic Aneurysm (JUSTICE) Registry Demonstrate Acceptable Limb Patency at 12 Months.

Recent reports of the Zenith Alpha abdominal endovascular graft (Zenith Alpha AAA, Cook, Inc., Bloomington, Indiana) have demonstrated an unexpectedly high incidence of limb graft occlusion (LGO). The purpose of this study was to prospectively evaluate the performance of the Zenith AAA in Japan, with a specific focus on LGO. All endovascular aneurysm repairs (EVARs) for abdominal aortic aneurysms performed using the Zenith Alpha AAA from July 2020 to October 2021 in 23 Japanese hospitals were prospectively evaluated. All computed tomographic images were analyzed in the core laboratory. Late complications were defined as any aneurysm-related events occurring >30 days after EVAR, including aneurysm sac enlargement of >5 mm and any reinterventions performed. Endoleaks without sac enlargement or reintervention were excluded as late complications. During the study period, 147 EVARs were performed using the Zenith Alpha AAA. The mean patient age was 76.5±7.7 years, 84.4% of patients were male, and the mean aneurysm diameter was 52.4±9.2 mm. Instruction-for-use violations were observed in 76 patients (51.7%), primarily associated with a severely angulated proximal neck (>60°). There were six intraoperative complications and 62 additional intraoperative treatments reported, most of which involved preemptive coil embolization of the inferior mesenteric artery (37 cases). Technical success, defined as the absence of type 1 or 3 endoleaks on final angiography, was achieved in 99.3% of patients. At 12 months, there was only one case of type 1/3 endoleak (0.8%) and one aneurysm sac enlargement exceeding 5 mm (0.8%); however, a high incidence of type 2 endoleaks was observed in 35.2% of patients, and aneurysm sac regression exceeding 5 mm was achieved in 30.1% of patients. Nine late complications were observed, and the rate of freedom from late complications at 12 months was 93.5%, encompassing four LGOs and one limb graft stenosis (3.4%). In contrast to recent reports, our Japanese multicenter prospective study demonstrated satisfactory early clinical results, including an acceptable LGO rate, for the low-profile Zenith Alpha AAA. Long-term follow-ups will be performed to confirm the persistence of these outcomes. This study prospectively evaluated the performance of 147 Zenith Alpha AAAs used for endovascular aneurysm repair with core-lab adjudication focusing especially on limb graft occlusion (LGO). At 12 months, aneurysm sac regression exceeding 5 mm was achieved in 30.1% of patients, and there was only one type 1/3 endoleak, one aneurysm sac enlargement (>5 mm), and nine late complications including five LGOs (3.4%), resulting in rate of freedom from late complications at 93.5%. Satisfactory early clinical results, including an acceptable rate of LGO can be achieved, particularly with cautious usage of the Zenith Alpha Spiral-Z Endovascular Leg." 5mm), and nine late complications including five LGOs (3.4%), resulting in rate of freedom from late complications at 93.5%. Satisfactory early clinical results, including an acceptable rate of LGO can be achieved, particularly with cautious usage of the Zenith Alpha Spiral-Z Endovascular Leg.

Early and Midterm Outcomes of Endovascular Aneurysm Repair With Zenith Alpha Abdominal Stent-Graft: Results From a Multicenter Retrospective Tuscany Registry.

Zenith Alpha Abdominal (Cook Medical, Bloomington, IN, USA) is one of the new-generation low-profile stent-grafts with demonstrated satisfactory early and midterm clinical outcomes for endovascular treatment of abdominal aortic aneurysms (AAAs). The aim was to evaluate early and midterm results of this device in the framework of a multicenter regional retrospective registry, with the analysis of morphological factors affecting outcomes, including different limb configurations. Between January 2016 and November 2021, 202 patients with AAA underwent elective endovascular aneurysm repair (EVAR) with implantation of a Zenith Alpha Abdominal in 7 centers. Early (30 day) outcomes in terms of technical and clinical success were assessed. Estimated 5 year outcomes were evaluated in terms of survival, freedom from type I/III endoleak, freedom from surgical conversion, freedom from limb graft occlusion, freedom from any device-related reintervention, and graft infection evaluation by life-table analysis (Kaplan-Meier test). A comparative analysis between different limb configurations (Zenith Spiral Z AAA iliac legs, codes ZISL vs ZSLE) was performed in terms of limb graft occlusion. The 30 day technical and clinical success rates were 97.5% and 99.5%, respectively. Median follow-up period was 25.5 months (interquartile range [IQR]: 12-43.25). The 5 year survival rate was 73.6%. The estimated 5 year outcomes in terms of freedom from type I/III endoleak, freedom from surgical conversion, freedom from limb graft occlusion, freedom from any device-related reintervention, and freedom from graft infection were 88.6% (95% CI [confidence interval]: 83.4%-93.1%), 95.8% (95% CI: 92.7%-97.1%), 93.6% (95% CI: 90.2%-96.8%), 87% (95% CI: 83.3%-91.6%), and 97.7% (95% CI: 95.1%-98.9%), respectively. About limb configuration, no differences were found in terms of 5 year freedom from limb graft occlusion (ZSLE 93.4% [95% CI: 89.8%-95.5%] vs ZISL 94.3% [95% CI: 90.1%-95.9%], p=0.342; log-rank 0.903). Zenith Alpha Abdominal in elective EVAR offered satisfactory early and 5 year outcomes with low complication rates. Limb graft occlusion continued to be an issue. Limb configuration did not affect outcomes. The authors describe satisfactory early and 5 year outcomes of Zenith Alpha Abdominal in elective endovascular aortic repair in the framework of a multicenter regional retrospective registry. At 5 years freedom from type I endoleak was 88.6%, and rate of endograft infections and conversions to open repair were very low. in the present study. Hot topic about about Zenith stent-graft still remains the limb graft occlusion with a 30-day overall rate of 2%, and estimated 5-year freedom from limb graft occlusion of 93.6%. Limb graft configuration did not affect limb graft occlusion rate. A standardized protocol including iliac stenting should be adopted to reduce kimb graft occlusion.

A Retrospective Evaluation of Intra-Prosthetic Thrombus Formation After Endovascular Aortic Repair in Cook Zenith Alpha and Medtronic Endurant II Patients

To investigate the occurrence of limb graft occlusion (LGO) and intra-prosthetic thrombus (IPT) formation in Zenith Alpha and Endurant II stent graft limbs. A single centre retrospective study was conducted on patients treated with the Zenith Alpha and Endurant II stent grafts between 2017 and 2019. All post-operative computed tomography angiography images were re-investigated for thrombus formation. Demographic, aneurysm, and stent graft data were collected and compared. LGO was defined as complete occlusion or significant stenosis (≥ 50% lumen diameter reduction). Logistic regression on pro-thrombotic risk factors was conducted. Freedom from LGO and overall limb IPT were compared using Kaplan-Meier analyses. Seventy-eight Zenith Alpha and eighty-six Endurant II patients were studied. The median follow up was 33 (IQR 25, 44) months for Zenith Alpha patients and 36 (IQR 22, 46) months for Endurant II patients (p= .53). LGO was seen in 15% (n= 12) of Zenith Alpha patients and 5% (n= 4) of Endurant II patients (p= .032), and freedom from LGO was significantly higher among Endurant II patients (p= .024). The Zenith Alpha stent graft was an independent risk factor for LGO (OR 3.9, 95% CI 1.1 - 13.4; p= .032). Among Zenith Alpha patients, limb flare compression within the main body gate was over represented in LGO patients (p= .011). There was no difference in freedom from overall limb IPT between the stent graft systems. For Endurant II limbs, IPT was significantly less common in the integrated ipsilateral limbs (without ETLW/ETEW stent graft limbs) (p= .044). Main endograft body IPT was correlated with overall limb IPT (p= .035). LGO was significantly more common among Zenith Alpha than Endurant II patients. Zenith Alpha limbs was an independent risk factor for LGO. There was no difference between stent grafts in overall limb IPT formation.

Percutaneous mechanical thrombectomy for limb graft occlusion after endovascular aneurysm repair: Results of a case series.

Limb graft occlusion (LGO) is a recognised complication after endovascular aneurysm repair (EVAR). We present outcomes of a case series of LGO treated by percutaneous mechanical thrombectomy (PMT). Six male patients (mean age 70.5 ± 7.5years) presented with LGO after EVAR (n = 4), fenestrated EVAR with an iliac branch device (n = 1), branched EVAR (n = 1). Median time to occlusion was 28.5(IQR 90) weeks; all occlusions were unilateral. The presenting symptom was intermittent claudication (n = 4), chronic limb-threatening ischaemia (n = 1) or acute limb ischaemia (n = 1). PMT was undertaken using the 10F Rotarex Rotational Excisional Atherectomy System (Becton, Dickinson and Company, Franklin Lakes, USA) with optional stenting/reline of the affected limb. LGO was cleared in all 6 cases by PMT with limb stenting (n = 4)/limb reline (n = 2)/outflow stenting (n = 2). Post-operatively, novel oral anticoagulant therapy supplemented prior antiplatelet therapy in all cases. Length of stay was 2 (IQR 19) days. All cleared limbs remain patent at median 15 (IQR 185) weeks follow-up. This case series indicates that percutaneous mechanical thrombectomy is associated with high technical success rates and subsequent acceptable ensuing short-to-midterm patency. This approach is a valid alternative to surgical interventions in such cases, and represents our primary approach when LGO is encountered after EVAR.

Limb graft occlusion after endovascular aneurysm repair with the Cook Zenith Alpha abdominal graft

ObjectivePrior reports of the low profile Zenith Alpha abdominal graft (Cook Medical Inc, Bloomington, IN) have shown impaired limb graft patency to be the primary causes of reintervention. Special notices from the manufacturer have indicated certain instructions for use (IFU) violations as the main reasons for these complications. In the present study, we assessed the incidence of limb graft occlusion (LGO) and analyzed the effects of the detailed anatomic risk factors for LGO highlighted in the IFU and previously reported studies. MethodsA retrospective study was performed of 241 patients treated with the low profile Zenith Alpha at a single institution from October 1, 2015 to September 30, 2018. All computed tomography angiograms were analyzed using three-dimensional software. Data were extracted from the electronic medical records until the end of the study period (December 31, 2020). The cumulative incidence of LGO and LGO-related reinterventions were assessed. A regression analysis was performed to evaluate the possible risk factors associated with the development of LGO at specified time points. These included aortic and iliac diameters, graft component oversizing, iliac tortuosity and calcification, overlap of graft components, proximal alignment of ipsilateral and contralateral legs, and sealing zone in the external iliac artery. Reader agreement of iliac calcification and tortuosity was assessed in patients with LGO. ResultsA total of 33 limbs (7%) in 27 patients (11%) had become occluded. The cumulative incidence of LGO was 7% (95% confidence interval [CI], 5%-9%) per limb up to 3 years postoperatively. The previously described risk factors for LGO were studied using regression analysis; however, no positive association with LGO was identified. Heavily calcified common iliac arteries (CIAs) and external iliac arteries were protective against LGO compared with noncalcified vessels up to 3 years postoperatively (decreased risk, 17% [95% CI, −27% to −7%]; P = .001; and 15% [95% CI, −26 to −5]; P = .005, respectively). The reader agreement of iliac calcification and tortuosity showed substantial agreement (CIA intrareader kappa = 0.75; CIA interreader kappa = 0.62) and almost perfect agreement (intrareader kappa = 0.85; interreader kappa = 0.84), respectively. ConclusionsThe cumulative incidence of LGO after endovascular aneurysm repair with the Zenith Alpha graft was 7% per limb up to 3 years postoperatively. None of the analyzed risk factors suggested by the IFUs or current literature were positively associated with LGO.

Outcome of endovascular treatment of internal iliac artery aneurysms: a single center retrospective review

PurposeTo evaluate the technical feasibility and clinical outcomes of endovascular treatment for internal iliac artery (IIA) aneurysms.Material and methodsThis was a retrospective analysis of 25 patients with 32 IIA aneurysms (mean diameter: 39.1 ± 12.6 mm) who underwent endovascular treatment over a 10-year period, and were available for follow-up. Univariate analysis was used to determine the association between variables (including aortoiliac involvement and technique) and outcome.ResultsThe IIA inflow was covered with an iliac stent graft (N = 29) or embolized with a plug (N = 3). The IIA outflow was embolized in all but one case in which there was thrombotic occlusion of outflow branches. Outflow embolization using plugs or coils was performed in the distal IIA or anterior/posterior trunks in 9 cases and distal IIA branches in 22 cases. During a mean follow-up period of 39.9 months, 31.2% of aneurysms demonstrated endoleak and 12.5% demonstrated enlargement. Univariate analysis revealed that endoleak was associated with technical failure (p = 0.01) and that endoleak rate was higher in patients who underwent distal IIA branch embolization (p = 0.03). No variable was associated with sac expansion. Major complication occurred in one patient who died from aneurysm rupture. Minor complications were reported in six patients who developed femoral pseudoaneurysm (N = 2, 8%), buttock claudication (N = 3, 12%), and limb graft occlusion (N = 1, 4%).ConclusionEndovascular treatment of IIA aneurysms effectively prevents sac expansion. Endoleak was more frequently observed in cases of technical failure and those in which distal IIA branches were embolized.Level of EvidenceLevel 3b, retrospective cohort study.

Geometrical Changes of the Aorta as Predictors for Thromboembolic Events After EVAR With the Anaconda Stent-Graft

Purpose: Thromboembolic events (TE), including limb graft occlusion (LGO) and distal limb embolization (DLE), are common complications after endovascular aneurysm repair (EVAR). The aim of this study was to find predictors for TE in patients treated with the Anaconda stent-graft for infrarenal aneurysms. Materials and Methods: Geometrical and anatomical variables were retrospectively analyzed in a consecutive Anaconda cohort. Pre- and postoperative CT scans were used to derive geometrical parameters length, curvature, torsion, and tortuosity index (TI) from the center lumen lines (CLLs). Limb characteristics, pre-to-post EVAR and mid-term-follow-up changes in the parameters were evaluated for their predictive value for TE. Results: Eighty-four patients (mean age 74±8.3 years, 74 men) were enrolled. The risk of TE was lowered with pre-to-post implant decreasing TI (steps of 0.05: OR: 1.30, 95% CI: 1.01-1.66, p=0.04), pre-to-post implant decreasing mean curvature (OR: 1.08, 95% CI: 1.01-1.16, p=0.03), and a larger degree of circumferential common iliac artery (CIA) calcification (OR: 0.98, 95% CI: 0.97-1.00, p=0.03). The only LGO predictor was the caudal relocation of maximal curvature after EVAR (OR: 1.01, 95% CI: 1.00-1.01, p=0.04). Preventors of DLE were CIA diameter (OR: 0.87, 95% CI: 0.76-0.99, p=0.04), circumferential CIA calcification (OR: 0.97, 95% CI: 0.95-1.00, p=0.03), mean and maximal curvature of the preoperative aortoiliac trajectory (OR: 0.86, 95% CI: 0.79-0.94, p<0.01 and OR: 0.97, 95% CI: 0.95-1.00, p=0.03, respectively) and pre-to-postoperative decrease in mean curvature (OR: 1.11, 95% CI: 1.02-1.21, p=0.02). Midterm TE predictors were length (OR: 0.95, 95% CI: 0.89-1.01, p=0.08) and torsion maximum location (OR: 1.01, 95% CI: 0.99-1.01, p=0.10). Conclusion: The present study confirms that treatment of infrarenal AAA with an Anaconda stent-graft is related to a relatively high TE rate which decreases with a pre-to-postoperative reduction in curvature and TI, and a larger degree of circumferential CIA calcification. In other words, more aortoiliac straightening and more circumferential CIA calcification may prevent TE development after EVAR with this stent-graft.

Limb Graft Occlusion Following Endovascular Aneurysm Repair for Infrarenal Abdominal Aortic Aneurysm with the Zenith Alpha, Excluder, and Endurant Devices: a Multicentre Cohort Study

Limb graft occlusion (LGO) is a serious complication after endovascular aneurysm repair (EVAR) and while device development enables treatment of increasingly complex aortic anatomy, little is known about how endograft type affects the risk of occlusion. This observational study aimed to explore the incidence of LGO after EVAR for three major endograft systems. All patients with standard EVAR as the primary intervention for infrarenal abdominal aortic aneurysm (AAA), between January 2012 and December 2018, at five Swedish vascular surgery centres, were included in this multicentre retrospective cohort study. LGO was defined as a total limb occlusion regardless of symptoms, or a treated significant stenosis. A nested case control (NCC) design with incidence density sampling of 1:3 was used for analysis of potential per-operative and morphological risk factors. Conditional logistic regression was used to estimate multivariable odds ratios (OR) with 95% confidence intervals (CI) RESULTS: A total of 924 patients were included. The majority were male (84%), the mean age was 76 years (± 7.5 SD), and median AAA diameter was 59 mm (IQR 55, 67). Patients were treated with Zenith Alpha (n= 315, ZISL limbs), Excluder (n= 152, PLC/PXC limbs), and Endurant (n= 457, ETLW/ ETEW limbs). During median follow up of 37 months (IQR 21, 62), 55 occlusions occurred (5.9%); 39 with Zenith Alpha (12.4%), one with Excluder (0.7%), and 15 with Endurant (3.3%). In the NCC analysis, the Zenith Alpha device (OR 5.31, 95% CI 1.97 - 14.3), external iliac artery (EIA) landing (OR 5.91, 95% CI 1.30 - 26.7), and EIA diameter < 10 mm (OR 4.99, 95% CI 1.46 - 16.9) were associated with an increased risk of LGO. Endograft device type is an independent risk factor for LGO after EVAR. Specifically, the Zenith Alpha demonstrated an increased risk of LGO compared with the Endurant and Excluder devices. In addition, a narrow EIA and landing zone in EIA are also risk factors for LGO.

Outcomes of Endovascular Aneurysm Repair Using the Anaconda Stent-Graft

Purpose: To report outcomes of elective endovascular aneurysm repair (EVAR) using the Anaconda stent-graft in a tertiary vascular center. Materials and Methods: A retrospective study was conducted of 271 patients (mean age 71.5 years; 260 men) who underwent elective EVAR for abdominal aortic aneurysm using the Anaconda stent-graft from January 2006 to January 2017. Median aneurysm diameter was 58 mm (range 50–90). All patients were anatomically suitable for EVAR according to the 2003 version of the instructions for use. Follow-up included computed tomography angiography at 1, 6, and 12 months and yearly thereafter for the first 4 years and then every 2 years. Primary outcomes included technical success and 30-day aneurysm-related mortality and complications; secondary outcomes were overall and aneurysm-related mortality and aneurysm-related morbidity in follow-up. Results: The Anaconda stent-graft was implanted successfully in all patients. Primary and secondary technical success rates were 99.6% and 100%, respectively. Three patients (1.1%) died within 30 days of causes unrelated to the aneurysm, while 15 patients (5.5%) suffered perioperative complications. Median follow-up was 72 months (range 14–141). The overall type I endoleak rate was 4.7% (11 proximal, 2 distal). Late aneurysm-related complications were observed in 48 patients (17.3%); aneurysm-related mortality was 1.4% (n=4). Non-aneurysm-related mortality was 21.0% (n=57). Freedom from reintervention was 95.2% at 1 year, 98% at 2 years, and 90% at 6 years. There was no significant difference in the overall limb graft occlusion rate between the second- and third-generation devices. Conclusion: Results in our cohort study demonstrate that the Anaconda stent-graft has satisfactory early and late results with low aneurysm-related mortality.

Endograft Device type is a Significant Risk Factor for Limb Graft Occlusion After Endovascular Aortic Repair of Infrarenal Abdominal Aortic Aneurysm

Introduction: Limb graft occlusion (LGO) is an uncommon yet serious complication after EndoVascular Aortic Repair (EVAR). It is reportedly influenced by several patient-specific anatomical variables. In a rapidly developing field of new vascular devices and an overall tendency toward endovascular treatment of complex aortic cases, minimising complications becomes increasingly important. Albeit worldwide clinical usage, there is still a lack of long-term follow-up data for many “second generation” endograft types. Our objective was to identify factors associated with LGO after EVAR. Methods: Between 2013-2018, all patients undergoing standard EVAR for infrarenal aortic aneurysms at two high-volume Vascular referral centers were included in this study. Cases treated with fenestrated or branched endografts were excluded. Patients were identified through a national registry for Vascular Surgery and all pertinent data was retrospectively collected from patient electronic medical records. LGO was defined as a symptomatic total limb occlusion requiring intervention. Results: Mean age at primary intervention for the 639 patients included was 75.3 years and 85.5% were men. Three graft manufacturers were predominantly used; Medtronic Endurant (n=274), Cook Zenith (n=243) and Gore Excluder (n=122). All grafts were bifurcated and the majority were deployed in an elective setting (77.5%). Median follow-up time for respective groups was 52, 21 and 25 months. A total of 29 patients presented with LGO (4.5%); 8 patients treated with Medtronic (2.9%), 19 with Cook (7.8%) and 2 with Gore (1.6%). Cox proportional hazard regression models were used to estimate multivariable hazard ratios (HR) with 95% confidence intervals (95% CI) of LGO during follow up. The multivariable HR of LGO was increased more than 6-fold in the Cook Zenith group, compared with Medtronic Endurant (HR, 6.14; 95% CI, 2.29 - 16.44), and Gore (HR 7.10; 95% CI, 1.55 - 32.57) respectively. There was no significant difference in rate of LGO when comparing Gore with Medtronic (HR, 0.87; 95% CI, 0.18-4.26). The observed point estimates in univariable models did not differ from those observed after adjustment for potential confounders in multivariable models. We observed no difference in rate of all cause mortality between the three groups. Conclusion: In this study, endograft device type was identified as an independent risk factor for LGO after EVAR. Specifically, limbs in the Cook Zenith endografts were observed to occlude at a 6 times higher rate compared with the Medtronic Endurant or Gore Excluder devices. [Rate of Limb Graft Occlusion] Disclosure: Nothing to disclose

Suitability of EVAR with Hostile Neck

AbstractBackground: Endovascular treatment of abdominal aortic aneurysms (EVAR) is now considered first line of treatment for abdominal aortic aneurysm (AAA) mainly due to the lower morbidity and mortality, hostile neck is a major obstacle in treating such patients, however many endovascular methods are available to overcome such obstacle, EVAR out of IFU is considered one of the lines of management. Further evaluation is needed.Aim of Study: Aim of this study was to evaluate the effectiveness of endovascular treatment of AAA with hostile neck anatomy, with commenting on the perioperative compli-cations, mortality and morbidity.Material and Methods: This study was done retrospectively over a period of 18 months including 10 patients who had endovascular treatment of abdominal aortic aneurysms with hostile neck anatomy.Results: 10 patients were included in this study primary technical success was achieved in 90% of cases while the last case needed aortic cuff as an adjunctive procedure. One case required re-intervention within 30 days post-operative due to limb graft occlusion, managed by femoro-femoral bypass. At one year follow up mortality was 10%.Conclusion: EVAR for AAA patients with HNA is feasible; patients with single feature of HNA showed the best outcome, while patients with more than one feature required the usage of adjunctive techniques for proximal sealing and were more liable to develop post-operative complications.

Real-Life Experience with Ovation Stent Graft: Lesson Learned from the First One Hundred Fifty Treated Patients

The objective of the study was to report immediate and midterm results of an unselected population of patients treated for abdominal aortic aneurysms (AAAs) by endovascular aneurysm repair (EVAR) using the Ovation stent graft. A double-center retrospective study was conducted on a prospectively collected database between 2012 and 2015. One hundred fifty-six elective patients were included. The outcome measures considered for analysis were primary technical success, 30-day and midterm reinterventions, and all-cause and AAA-related mortality rates. The presence of an aortic neck ≤10 mm, and of a noncylindrical aortic neck, as well as a narrowed aortic bifurcation was defined as an aortic bifurcation average diameter (ABaverage) ≤ 18mm or an ABarea ≤ 20mm2, and an external iliac artery diameter ≤5mm was considered as independent factors potentially influencing the outcome. Male patients totaled 128 (82.1%), and mean age was 74.83±6.76years (range: 56-91). Mean aortic diameter was 57.15±8.77mm, mean diameter at inferior renal artery level + 13 was 24.44±3.31mm, and mean aortic neck length was 18.77±8.45mm. Fifty-four patients (34.6%) had an aortic neck ≤10mm, and cylindrical aortic neck shape was presentin34 patients (21.8%). Regarding the aortic bifurcation (AB), 31 patients (19.9%) presented ABaverage ≤ 18mm, and 35 (22.4%) an ABarea ≤ 20mm2. Technical success was achieved in all cases. At 30-day follow-up, 2 type I endoleaks (1.3%) were detected. One patient was successfully treated endovascularly by proximal aortic cuff implantation, while the other patient refused further treatment. Three-month unscheduled computed tomographic angiography shows endoleak resolution and complete aneurysm seal. One patient suffered from a limb graft occlusion, managed by medical treatment. At a mean follow-up time of 20.4±8.8 (1-60) months, 6 reinterventions were reported, including 2 embolizations for type II endoleak and 4 for iliac and femoral vessel occlusive disease. Log-rank test on preoperative anatomical features showedno significant differences in terms of freedom from reinterventions, and P values were 0.653 for aortic neck length ≤10mm, 0.309 for noncylindrical aortic neck length shape, 0.520 for ABaverage ≤ 18mm, 0.604 for ABarea ≤ 20mm2, and 0.421 for external iliac artery diameter ≤5mm. Our initial experience suggests that in an unselected patient population undergoing AAA repair, EVAR by Ovation stent graft can be performed safely with satisfactory immediate and midterm outcomes.

Limb graft occlusion following endovascular aortic repair: Incidence, causes, treatment and prevention in a study cohort.

The present study investigated the incidence, causes, treatment and prevention of limb graft occlusion following endovascular aortic repair (EVAR). A total of 66 cases of abdominal aortic aneurysm receiving EVAR at our department from January 2005 to December 2013 were enrolled. After EVAR, patients received routine antiplatelet therapy of 75 mg PLAVIX for 6 months and then 100 mg Aspirin for another 6 months by oral administration. According to previous clinical experiences, antiplatelet therapy is able to effectively reduce the incidence of iliac occlusion after EVAR. A total of 61 bifurcated grafts and 5 aortauniilac grafts (127 limbs in total) were used. Physical examination, ankle-brachial-index and computer tomographic angiography were performed at 10 days, at 3, 6 and 12 months and annually thereafter. It was found that 7 limbs in 7 patients (10.6% of patients, 5.5% of limbs) were occluded between 20 days and 12 months (average, 7.8±5.3 months) after EVAR. Acute and severe ischemia was found in 2 cases, claudication was in found 3 cases, asthenia in both legs was found in 1 case and 1 case was asymptomatic. Femoral-femoral bypass, femoral-femoral bypass and stenting, aorto-iliac/femoral bypass, thrombectomy and conservative treatment were performed in 1 patient each and thrombectomy together with stenting was performed in 2 cases. Limb graft occlusion was not rare after EVAR. Treatment of this complication included surgery and endovascular therapy such as bypass, thrombectomy and thrombolysis. In conclusion, aggressive pre-emptive treatment including angioplasty and stenting prevented occlusion in certain cases.

Application and effect observation of hybrid aortic stent grafts for endovascular repair in the treatment of complicated infrarenal abdominal aortic aneurysm

To evaluate the effectiveness of the hybrid graft technique for complicated infrarenal abdominal aortic aneurysms (AAAs). The clinical data of 183 patients who underwent endovascular aneurysm repair (EVAR) for AAA with challenging anatomy at Zhongshan Hospital Affiliated to Shanghai Fudan University from 2010 to 2015 were retrospectively analyzed. Endografts were divided into two groups: Hybrid Group (28 cases) used more than one type of stent graft, and Standard Group (110 cases) used only one stent graft type. Patients were recommended to undergo CT angiography at 1, 3, 6, 12 month after the procedure. Clinical data were analyzed with a focus on postoperative hospital stay, endoleak, limb occlusion, complications of approach, complications of system, converted to open operation and secondary intervention. Technical success was achieved in all patients in both groups. Compared with hybrid group and standard group, there was no difference in postoperative hospital stay ((5.35±2.99) and (5.92±3.70) days, t=0.753, P>0.05). During the follow up, there was no difference in endoleak (10.7% and 18.2%), limb graft occlusion (3.6% and 10.9%), complications of approach (0 and 1.8%), complications of system (7.1% and 0.9%), converted to open operation (0 and 0.9%) between two groups (χ(2)=0.896, 1.408, 0.517, 4.078, 0.256, all P>0.05). However, there was statistically significant difference in secondary intervention between two groups (3.6% and 19.1%, 2=4.011, P<0.05). The use of hybrid stent graft in patients with unfavorable neck and iliac artery anatomy AAA is feasible, and it could improve the postoperative outcomes such as secondary intervention rate.

A modified technique for Gore Excluder limb deployment in difficult iliac anatomy during endovascular abdominal aortic aneurysm repair

Complex iliac anatomy including extreme tortuosity constitutes a relative contraindication for endovascular abdominal aortic aneurysm repair with additional risk of limb-graft occlusion. The Gore Excluder limb-graft is a flexible stent-graft, which adapts easily to iliac tortuosity. Nevertheless, the presence of the stiff guide wire does not always allow for an ideal apposition of the stent graft to the angulated common iliac artery vessel wall. We describe herein a modified technique for Gore Excluder limb-graft deployment with partial removal of the stiff wire in cases with difficult tortuous or narrow iliac arteries during endovascular abdominal aortic aneurysm repair.

Early experience with ovation endograft system in abdominal aortic disease

ObjectiveWe describe our initial experience with the use of the TriVascular Ovation endograft system for the treatment of abdominal aortic aneurysms (AAA).MethodsWe retrospectively reviewed data from patients treated for AAA using the Ovation endograft at two institutions from January 2011 to September 2012. Main outcomes included primary success, survival, complications, and device-related events. The mean follow-up period was 10 months (range 1–22 months).ResultsThirty-seven patients (male: 95%, mean age: 76 yr) were treated for AAA (mean diameter: 54 mm) with the Ovation endograft. Local or regional anesthesia was used in 86.5% of cases. Percutaneous access was utilized in 73% of cases. Primary success was 89.2% (33/37). Four adjunctive procedures were required including two distal extensions (type 1b endoleak and iliac limb disconnection resulting in type III endoleak) and two bypass surgeries (limb graft occlusion and gate cannulation failure). No deaths or major complications were reported during the procedure or in follow-up. No type I, III, or IV endoleak, AAA enlargement, AAA rupture, stent fracture, migration, or endovascular or surgical reintervention were reported during the follow-up period. Type II endoleak was observed in two patients. Asymptomatic narrowing of both iliac limbs was observed in one patient at 6 months.ConclusionsOur initial experience with the Ovation endograft demonstrated encouraging results in patients with AAA.