Bifurcated Stent Graft Research Articles

Multicentric Use of Commercially Available Infrarenal Endografts During Fenestrated Endovascular Aortic Repair: A Feasibility Study.

This study aimed to assess the feasibility and short-term outcomes of different manufactured proximal and distal stent graft components during fenestrated endovascular aortic repair (FEVAR). A multicenter retrospective review was conducted at 3 aortic centers, involving all consecutive patients who underwent FEVAR utilizing a customized Dacron-based tubular proximal and a distal bifurcated polytetrafluoreten (PTFE)-based commercially available stent grafts. Primary outcomes were 30 day mortality, major adverse events, and technical and clinical success. Secondary outcomes assessed stent graft migration, occurrence of types I/III endoleak, and reintervention. A total of 23 FEVAR cases across all centers were included in this study. Technical success was achieved in all cases, with a median procedure time of 183 (153-244) minutes. There were no major adverse events, except for 1 transient acute renal failure. The median follow-up period was 23 (17-28) months. All target vessels retained patent with the exception of 1 right renal fenestration that showed signs of kinking at the first follow-up, and despite secondary intervention with relining and distal extension, there was an occlusion afterward and 1 hepatic artery with a separate fenestration. This and 1 successful relining of a superior mesenteric artery kink were the only reinterventions in this cohort. One case of persistent type 1b endoleak was reported in a patient with chronic type B aortic dissection, which resolved with distal extension on the external iliac artery 5 months after the index procedure. No deaths occurred throughout the follow-up with, and there were no signs of stent graft migration or type 3 endoleak. The use of commercially available PTFE-based bifurcated stent grafts to extend distally the tubular graft appears to be a feasible approach during FEVAR, with promising short-term outcomes. Further studies are necessary to define the applicability of this solution and evaluate long-term outcomes. This multicentric study on fenestrated endovascular aortic repair (FEVAR) demonstrates the feasibility and good short-term outcomes of utilizing a PTFE-based commercially available stent graft to extend the proximal tubular custom-made fenestrated stent graft. The high technical success rate, absence of major adverse events, and low occurrence of complications such as stent graft migration and endoleaks highlight the potential clinical benefits of this approach with an off-the-shelf distal extension whose delivery system does not cross the fenestrations intraoperatively.

Off-the-Shelf Single-Fenestrated Endograft for Emergent Juxtarenal and Pararenal Abdominal Aortic Aneurysm.

Endovascular solutions to emergent juxtarenal and pararenal abdominal aortic aneurysms (AAAs) are complicated. Endovascular aortic repair (EVAR) with in situ laser fenestration (ISLF) is promising but requires a period of visceral ischemia. With an off-the-shelf, single superior mesenteric artery (SMA)-fenestrated device mesenteric ischemia is avoided and renal ischemia decreased. The aim was to develop an optimized design of such an endograft suitable for >90% of juxtarenal and pararenal AAAs. Single-center analysis on 44 consecutive preoperative CTs for previously elective fenestrated EVARs for juxtarenal and pararenal aneurysms. Anatomical characteristics were analyzed to define: (1) shortest aortic coverage above SMA fenestration to achieve ≥4 cm seal; (2) feasibility of a scallop for the celiac artery; (3) shortest distance between the SMA and lowest renal, to facilitate renal ISLF in a straight endograft; (4) distance from the lowest renal to the aortic bifurcation, to allow an overlapping zone >40 mm with a bifurcated stent graft; (5) aortic diameter in the sealing zone, for optimal proximal stent graft diameter with 10% to 30% oversizing; (6) the final design was then tested on individual level. (1) The stent graft needs to start 40 mm above the SMA fenestration to achieve a 4 cm sealing zone in >90% of cases. (2) A proximal sealing zone of 40 mm without a scallop covers 77% of celiac arteries. With an addition of a 20 mm deep, 20 mm wide scallop at 12:30, the stent graft still covers 27% of celiacs. This suggests that a scallop would not be practically feasible. (3) In >90% of cases, the lowest renal was <31 mm from the SMA, suggesting that the tapering should start 30 mm below the SMA. (4) The distance from the lowest renal to the aortic bifurcation ranged from 82 to 166 mm. This allows for a 20 mm tapering and 50 mm straight part in all cases. (5) The 5th and 95th percentile of the aortic diameter in the sealing zone was 22 and 31 mm, respectively. Thus, 2 different stent graft diameters (28 and 34 mm) would fit >90% of cases. (6) The final design was suitable in 91% cases. Two sizes of a single-fenestrated aortic stent graft without scallop cover >90% of juxtarenal and pararenal anatomies. Emergent juxta- and pararenal aortic aneurysms is a difficult clinical scenario that continuously challenges physicians. An endovascular option is in situ laser fenestrated endografts. One risk with these is the complete visceral ischemia occurring before the fenestrations are completed. An off-the-shelf single-fenestrated stent graft facilitates the treatment by removing the ischemia time for the SMA and reducing the ischemia time for the celiac and renal arteries thus decreasing the risk of visceral ischemia complications.

Augmented Reality Improves Learning Curve of Endovascular Navigation

Intra-Operative Positioning System (IOPS) (Centerline Biomedical, Cleveland, OH) is a 3D electromagnetic (EM) endovascular navigation system approved by the US Food and Drug Administration and developed as an adjunct to fluoroscopy. It provides real-time 3D display of sensorized material on an anatomical map on a flat screen. An investigational prototype based on IOPS incorporates the ability to map implanted stent grafts and visualize the stents and anatomy using augmented reality headset. The aim of this study was to compare the completion of bifurcated stent graft gate cannulation performed by participants of varying experience using fluoroscopy or different variations of IOPS. The task was cannulation of the gate of a bifurcated aortic endograft deployed into a 3D printed abdominal aortic aneurysm model connected to flow pump reproducing physiological conditions, performed in a hybrid operating room (GE Allia IGS 7). Each participant performed the tasks with fluoroscopy, EM guidance with flat screen display (EM-FS), and EM guidance with augmented reality headset (EM-AR) (Fig 1), in randomized order. All participants used the same sensorized guidewire and steerable sensorized 6F catheter for the three runs. Participants were classified in three groups of experience. Primary end points included cannulation time and technical success, defined as the advancement of the catheter over the guidewire within the graft main body. Fifteen minutes was the cutoff time for each trial. There were 26 participants including 13 endovascular naïve trainees (group 1), 12 in training surgeons (group 2) and one advanced level vascular surgeon. In group 1, mean cannulation time was lower using EM-AR versus fluoroscopy (4.3 ± 4.4 vs 7.1 ± 4.9 minutes; P = .04), with no difference between EM-FS and fluoroscopy (6.3 ± 4.5 vs 7.1 ± 4.9 minutes; P = .63). In group 1, technical success was 77% with fluoroscopy and 92% with both EM modalities (P = .59). In group 2, there was a trend toward shorter times with EM-FS or EM-AR as compared to fluoroscopy (mean of 2.5 ± 0.9, 4.4 ± 4.0 and 5.2 ± 4.5 minutes, respectively). In group 2, technical success was 92% with fluoroscopy and 100% with IOPS (P > .99). The advanced level vascular surgeon repeated the cannulation task four times for each endovascular approach, with 100% technical success and no difference in mean time (P = .89) (Fig 2). Augmented reality allows for reducing the gate cannulation time as compared to fluoroscopy in participants with no previous experience in endovascular navigation. This auspicious finding suggests that augmented reality can be beneficial for individuals early in their career and can mitigate the learning curve.Fig 2Mean cannulation times of bifurcated stent graft gate cannulation using electromagnetic (EM) guidance with flat screen display or augmented reality compared to fluoroscopy, performed by operators of varying experience.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Type III endoleaks after endovascular aneurysm repair for abdominal aortic aneurysm: a case series

Background: Owing to the increased number of endovascular aneurysm repairs (EVAR) for abdominal aortic aneurysms (AAA), the number of patients requiring reinterventions for type III endoleaks is also growing.Objective: To analyze our experience in treatment of type IIIa and IIIb endoleaks after EVAR.Methods: Of 457 patients treated by EVAR between 2010 and 2019, type IIIa and IIIb endoleaks were detected in 5 (1.1%) patients: 4 men and 1 woman. Their mean age was 67.2 years.Results: Type IIIa and IIIb endoleaks were found in an average of 77.4 months after EVAR. The incidence of type III endoleaks was 1.1%. Type IIIb and IIIa endoleaks were observed in 1 and 4 cases, respectively. In one case, type IIIa endoleak resulted in a ruptured AAA. The main treatment methods were relining (n = 1), stent graft implantation (n = 4), implantation of a bifurcated stent graft into a stent graft. No intraoperative complications or perioperative mortality were reported. 100% of the interventions were successful. In the long-term follow-up period, 2 patients had reinterventions. One patient required an intervention for type IIIa endoleak on the contralateral side, and the other patient was diagnosed with type Ia endoleak after type IIIb endoleak treatment. In the long-term follow-up period, no ruptured aneurysms or deaths were reported.Conclusion: Type III endoleaks are associated with a risk of AAA rupture and require treatment. Endovascular treatment of endoleaks demonstrated good immediate results; however, due to the high risk of endoleaks requiring reintervention, further long-term follow-up is needed. Received 18 November 2022. Revised 15 December 2022. Accepted 19 December 2022. Informed consent: The patient’s informed consent to use the records for medical purposes is obtained. Funding: The study did not have sponsorship. Conflict of interest: The authors declare no conflict of interest. Contribution of the authors: The authors contributed equally to this article.

Floating Thrombus after Endovascular Aneurysm Repair with a Bifurcated Stent Graft

Floating Thrombus after Endovascular Aneurysm Repair with a Bifurcated Stent Graft

A 12-year experience of endovascular repair for ruptured abdominal aortic aneurysms in all patients

ObjectiveEndovascular aneurysm repair (EVAR) has been increasingly performed for ruptured abdominal aortic aneurysms (rAAAs). However, multiple randomized trials have failed to demonstrate a survival benefit compared with open aortic surgery. During a 12-year period, 100% of patients without a history of aneurysm surgery had undergone EVAR for a rAAA at Örebro University Hospital, with no emergent open aortic surgery performed. In the present study, we evaluated the mortality and technical success during this “EVAR-only” period. MethodsA single-center, retrospective observational study was conducted. We identified all patients who had presented to Örebro University Hospital with a rAAA between October 2009 and September 2021. Patients with isolated iliac artery, thoracic, and thoracoabdominal aortic ruptures were not included. Patients who had received previous aortic interventions (open or endovascular) and patients who had received palliative treatment instead of surgical intervention were also excluded. The patient characteristics, perioperative and postoperative data, and mortality rate were investigated. ResultsEVAR had been performed in 100 patients. Preoperative hemodynamic instability had been present in 54 patients (54%), and 18 (18%) had undergone aortic balloon occlusion. The aneurysm location was infrarenal in 89 patients (89%). Bifurcated stent grafts had been used in 97 patients (97%), and adjunct endovascular techniques had been used for 27 patients (27%). Of 98 patients, EVAR had been performed with the patient under local anesthesia for 62 patients (63%). Peri- and postoperative complications at 30 days had occurred in 20 of 100 patients (20%) and 22 of 79 patients (28%), respectively. The overall mortality at 30 days was 27% (27 of 100 patients), and the mortality for those with an isolated infrarenal rAAA was 24% (21 of 89 patients). The overall mortality at 1 year was 39% (39 of 100 patients) and for those with an isolated infrarenal rAAA was 37% (33 of 89 patients). The presence of preoperative hemodynamic instability and the use of ABO were statistically significantly and independently associated with increased 30-day mortality on multivariate logistic regression analysis. ConclusionsAll 100 patients who had undergone surgery for a rAAA had been treated using EVAR and endovascular adjuncts, with a relatively low mortality rate, thus continuing the “EVAR-only” approach. A low proportion of rAAA patients were considered surgically unsuitable. These findings support the applicability of EVAR for the treatment of all rAAAs at suitable centers.

Tailored Endovascular Reconstruction of Infrarenal Aorta and Aortic Bifurcation With Covered Reconstruction of Aortic Bifurcation and Unimodular Stent Graft for Obstructive Arterial Disease

The covered reconstruction of aortic bifurcation (CERAB) technique is a feasible approach for extensive aortoiliac obstructive disease. Some limitations were observed in the wide aortic lumen, with a maximum diameter at the proximal landing zone >16 mm. In these cases, unimodular stent graft deployment (AFX Unibody) might overcome these limitations to obtain anatomic reconstruction of the aortic bifurcation. This study evaluated the outcomes of endovascular recanalizations on aortoiliac obstructions using the CERAB technique and unimodular stent grafts.

Multiple concomitant arterial aneurysms in Behçet's disease.

Behçet's disease (BD) is a rare form of systemic vasculitis that affects small to large vessels. It is characterized by mucocutaneous, pulmonary, cardiovascular, gastrointestinal, and neurological manifestations. Large vessel involvement may occur in a third of cases. Veins are usually more affected than arteries. Furthermore aneurysms are the most frequent arterial complication. A 41-year-old man presented with multiple arterial aneurysms. He had previous medical history of a right popliteal aneurysm treated with a reversed femoro-popliteal venous bypass, long-term steroids and immunosuppressive treatment. On admission, diagnostic computed tomography angiography revealed multiple aneurysms, including an 87mm aneurysm of the femoro-popliteal bypass and an abdominal aortic and left common iliac artery aneurysm. He received an intensification of medical treatment with methylprednisolone and infliximab intravenous infusion. Aorto iliac artery aneurysms were treated by infrarenal bifurcated stent graft implantation. The aneurysm of the venous femoro-popliteal bypass was treated by explantation and prosthetic repair. One month later, he presented with acute right limb ischemia related to occlusion of the right limb of the stent graft despite anticoagulation which was treated by mechanical thrombectomy. Vascular BD can worsen the vascular outcome after surgery. Except in an urgent context, BD must be controlled before surgery. This case report illustrates the importance of combined medical and surgical management, with first BD activity control with corticosteroids and immunosuppressive treatment, then surgical or endovascular treatment.

Intraoperative cone beam computed tomography to improve outcomes after infrarenal endovascular aortic repair

ObjectiveWe evaluated whether a combination of intraoperative contrast-enhanced cone beam computed tomography (ceCBCT) and postoperative contrast-enhanced ultrasound (CEUS) after infrarenal endovascular abdominal aortic aneurysm repair (EVAR) could reduce late stent graft–related complications and, consequently, reintervention. MethodsAll consecutive patients who had received infrarenal bifurcated stent grafts in our hybrid room (IGS 730; GE Healthcare, Île-de-France, France) during two discrete periods were included in the present study. From November 2012 to September 2013, two-dimensional completion angiography was performed after each EVAR, followed by computed tomography angiography (CTA) before discharge (group 1). From October 2013 to January 2015, intraoperative ceCBCT was performed, followed by CEUS within the first postoperative days (group 2). Comparative analyses of the outcomes were performed. The primary endpoint was late stent graft–related complications, a composite factor incorporating aneurysm-related death, type I or III endoleaks, kink or occlusion of the iliac limb, and aortic sac enlargement after the first 30 postoperative days. The secondary endpoint was all stent graft–related reinterventions. All-cause and aneurysm-related deaths were also recorded. ResultsOverall, 100 consecutive patients (50 each in groups 1 and 2) were enrolled, with a median follow-up of 60 months (interquartile range, 41-69 months). At 60 months after the index procedure, the freedom from late stent graft–related complications in each group was 61.6% (95% confidence interval [CI], 47.0%-80.6%) for group 1 and 81.7% (95% CI, 70.1%-95.2%) for group 2 (P = .033). The use of intraoperative ceCBCT was independently associated with a reduced rate of late stent graft–related complications on multivariate analysis (hazard ratio, 0.39; 95% CI, 0.16-0.95; P = .038) but did not appear to significantly protect against stent graft–related reinterventions (hazard ratio, 0.53; 95% CI, 0.20-1.39; P = .198) or all-cause death (P = .47). ConclusionsTo the best of our knowledge, the present study is the first to report the influence of routine ceCBCT on late outcomes after EVAR. The use of ceCBCT shows the potential for reducing late stent graft–related complications associated.

Endovascular Repair of Penetrating Aortic Ulcers: Indications and Single-Center Mid-Term Results

Although endovascular repair is used to treat penetrating aortic ulcers (PAUs), the indications for endovascular repair in PAUs remain controversial. The current study evaluated the mid-term results of endovascular repair for PAUs and further explored the endovascular indications for PAUs. We retrospectively reviewed the clinical data of patients who were diagnosed with PAUs and underwent endovascular repair in our department from October 2018 to August 2020. Endovascular indication included persistent or recurring symptoms, a maximum diameter of the PAU of greater than 20 mm, a maximum depth of the PAU of greater than 10 mm, an increase in the diameter of the aorta at the ulcer of greater than 10 mm annually, and multiple ulcers at the same or adjacent level of the aorta. Patient characteristics, anatomical parameters of the PAU, characteristics of endovascular repair and follow-up data were analyzed. 15 patients were included in the study. 3 patients had PAUs in the aortic arch, 6 PAUs were in the descending thoracic aorta, 4 PAUs were in the abdominal aorta, and 2 PAUs were in the descending thoracic and abdominal aortas. The average age was 70.60±8.27 years. Eight patients were symptomatic. The average depth of the PAUs was 7.32±2.74 mm, and the average diameter was 15.03±6.10 mm. The average operation time was 95.60±33.11 min. Postoperative hospital stay was 3.33±0.61 days. A left subclavian artery chimney stent was implanted in 3 aortic arch cases and 1 occluded case without adverse symptoms during the follow-up period. A bifurcated stent graft was placed in 3 abdominal aorta cases and exhibited good patency during the follow-up period. The duration of follow-up ranged from 3 to 24 months. The follow-up results showed that all PAUs were treated satisfactorily by endovascular repair, and no endoleaks or stent graft-related complications occurred. Endovascular repair is a safe and effective treatment for PAUs, and it may be safely performed in elderly patients and patients with comorbidities. The endovascular indications for PAUs must be further studied and optimized.

Pott’s Disease

A 64 year old man with a recent diagnosis of spinal tuberculosis was admitted to the emergency department after routine computed tomography angiography (CTA) for a mycotic infrarenal aneurysm. He had been on oral tuberculostatic therapy for two days. (A) The CTA revealed a large 75 mm aneurysm with psoas muscle infiltration (arrow). The aneurysm was urgently excluded with a bifurcated stent graft (Endurant II; Medtronic, Santa Rosa, CA, USA) under local anaesthesia. (B) Three weeks later his lumbar spine was reconstructed in a two step operation shown in the abdominal Xray.Image 1

The Reversed STABILISE Technique

A 64 year old man presented with acute abdominal and chest pain. (A) Computed tomography angiography showed an 84 mm infrarenal aortic aneurysm with retrograde aortic dissection arising from the aneurysm (blue arrow, entry tear) to the middle of the thoracic aorta (red arrows, dissection limits). Owing to persistent abdominal pain, he underwent endovascular aortic repair using an infrarenal bifurcated stent graft (WL Gore, Flagstaff, AZ, USA), followed by bare stenting of the upper abdominal and descending aorta (Cook Medical, Bloomington, IN, USA). Both grafts were expanded as per the STABILISE technique, allowing complete exclusion of the aneurysm and dissection (B).

Unibody design for aortic disease with a narrow aortic bifurcation: tips and tricks for success.

BackgroundSurgical management of patients with abdominal aortic diseases associated with distal narrowing is a challenging situation.ObjectivesTo evaluate outcomes of unibody bifurcated endovascular stent graft repair.MethodsThis is a retrospective, observational, multi-institutional database study of a cohort of consecutive cases, approved by the local Ethics Committee. Records were reviewed of patients diagnosed from 2010 to 2020 with “shaggy” aorta, saccular aneurysm, penetrating aortic ulcer, and isolated aortic dissection located in the infrarenal abdominal aorta. All patients were treated with a unibody bifurcated stent graft. Main outcomes were technical success, procedure complications, long-term patency, and mortality in the follow-up period up to 5 years. Data on demographics, comorbidities, surgical management, and outcomes were analyzed.ResultsTwenty-three patients were treated with unibody bifurcated stent graft repair, including 7 cases of “shaggy” aorta, 3 isolated dissections of the abdominal aorta, 4 penetrating aortic ulcers, and 9 saccular aneurysms. Immediate technical success was achieved in 100% of cases. At follow-up, all stent grafts remained patent and there were no limb occlusions. The patients were symptom-free and reported no complications related to the procedure. There were 5 deaths during the follow-up period (median= 4 years), but none were related to the procedure and there were no aorta-related deaths.ConclusionsThe present study shows that unibody bifurcated stent grafting is safe and effective in this group of patients with narrow distal abdominal aorta and complex aortic pathology. The results were similar for both infrarenal aortic aneurysms and aorto-iliac atherosclerotic disease.

Endovascular Aneurysm Repair with Bifurcated Stent Grafts in Patients with Narrow Versus Regular Aortic Bifurcation: Systematic Review and Meta-analysis of Comparative Studies

Narrow aortic bifurcation (NAB) is considered as a risk factor for endograft limb thrombosis. The purpose of the study was to investigate the effect of narrow aortic bifurcation on outcomes of elective endovascular aneurysm repair (EVAR). A systematic review that conformed to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed. We searched electronic bibliographic databases using a combination of controlled vocabulary (thesaurus) and free-text terms to identify relevant studies comparing outcomes of EVAR in patients with NAB versus those with regular aortic bifurcation. Pooled estimates of dichotomous outcomes were calculated using odds ratio (OR) and those of continuous outcomes using mean difference and 95% confidence interval (CI). To account for expected heterogeneity, the random-effects model was applied for statistical analysis. Six observational studies were included, reporting a total of 2,673 patients (412 with NAR and 2,261 with friendly anatomy). Perioperative mortality was similar between the groups (OR 1.14, 95% CI 0.30-4.34, P=0.85, I2=0%). Limb stenosis and kinking requiring additional intraoperative procedures was significantly more common among patients with NAB (OR 3.02, 95% CI 2.16-4.22, P<0.00001, I2=0%). Nevertheless, 30-day reintervention rate was similar between the groups, as was the rate of limb occlusion during follow-up. Available evidence suggests that at the expense of significantly more intraoperative additional procedures, EVAR with bifurcated devices can be safely performed in patients with NAB.

Treatment Results of Endovascular Aneurysm Repair Using the Parallel Stent-Graft Double D Technique for Distal Saccular Abdominal Aortic Aneurysms and Common Iliac Aneurysms

Endovascular aneurysm repair (EVAR) using a bifurcated stent graft may involve technical challenges when aortic disease (aneurysm or dissection) consists of a length <70mm between the inferior renal artery and aortic bifurcation or narrow aortic bifurcation that is common in asymmetric distal abdominal aortic aneurysms (AAAs) or iliac artery aneurysms (IAAs). We use EVAR with the double D technique (DDT-EVAR) for such cases, which involves straight type of stent grafts with same diameter in left and right that are deployed parallel to an aortic cuff that has been previously placed. In addition, DDT-EVAR can preserve the inferior mesenteric artery (IMA) for IAA. DDT-EVAR was performed for 21 of 910 (2%) cases from April 2007 to April 2019 at our institution. The median patient age was 74years (range, 52-85). Nineteen patients (90%) were men. Six patients (all saccular; 1 rupture) had AAAs, 12 had IAAs, and 3 had chronic type B aortic dissociation (TBAD) for re-entry closure. AAA and IAA had diameters of 45mm (range, 34-71) and 34mm (range, 25-58), respectively. An aortic cuff was used for 19 (90%) cases. Endurant II (Medtronic, Santa Rosa, CA) was used for 12 cases. The Excluder (W.L. Gore & Associates, Inc, Flagstaff, AZ) was used for 7 cases. Endurant II was used for 20 cases, and the VBX (W.L. Gore & Associates, Inc) was used for 1 case as stent-graft limbs. The procedural success rate was 100%. The median operative time was 146min (range, 88-324). IMA planned for preservation was successful for all 12 cases. Type I and type III endoleaks were not observed. With TBAD, flow to the false lumen decreased or disappeared, and no complications during the hospital stay were associated with the procedure. For 2 patients whose procedure involved Endurant II stent-graft limb, limb occlusions were observed postoperatively, and reintervention was required. No other patients required additional treatment at a median follow-up of 18months (range, 4-50). DDT-EVAR is a safe and straightforward technique for the treatment of distal AAA, common iliac artery aneurysm, and TBAD. It may help preserve the IMA and internal iliac artery, even when it is impossible to preserve them with a bifurcated stent graft.

Treatment Results of Endovascular Aneurysm Repair Using the Parallel Stent Graft Double D Technique for Distal Aortic and Common Iliac Aneurysms

Endovascular aneurysm repair (EVAR) using a bifurcated stent graft may involve technical challenges when asymmetric distal abdominal aortic aneurysms (AAAs) and iliac artery aneurysms (IAAs) are encountered, especially with inferior renal artery aortic bifurcation <70 mm or narrow aortic bifurcation. We use EVAR with the double D technique (DDT-EVAR) for such cases. This involves a stent graft limb with the same diameter as the left and right diameters that is deployed parallel to an aortic cuff that has been previously placed (Fig).

Unibody Endograft Using AFX 2 for Less Invasive and Faster Endovascular Aortic Repair: Protocol for a Multicenter Nonrandomized Study.

BackgroundSince the introduction of endovascular aortic repair (EVAR) for treatment of abdominal aortic aneurysms (AAAs), progressive improvements in results have been achieved. However, conventional bifurcated stent grafts have been proven to have a nonnegligible risk of failure and secondary intervention, principally due to the lack of adequate proximal sealing. The unique AFX 2 Endovascular AAA System (Endologix, Irvine, CA) unibody device, which provides different sealing and fixation features compared with conventional devices, seems to overcome these limitations.ObjectiveThe aim of this study is to evaluate intraoperative, perioperative, and postoperative results in patients treated with the AFX 2 Endovascular AAA System endografts for elective AAA repair in a large cohort of consecutive patients.MethodsAll eligible EVAR patients will be included in this observational, multicenter, prospective, nonrandomized study. The number of patients to be enrolled is 500.ResultsThe primary endpoint of the study is to evaluate the technical and clinical success of EVAR with unibody endografts in short- (90-day), mid- (1-year), and long-term (5-year) follow-up periods. The following secondary endpoints will also be addressed: operative time, intraoperative radiation exposure, contrast medium usage, AAA sac shrinkage at 12-month and 5-year follow-up, and any potential role of patients’ baseline characteristics and device configuration on primary endpoint. The actual start date of the investigation was November 2019. The final patient is expected to be treated by the end of December 2020, and the estimated study completion date is December 2025.ConclusionsThis study will provide verified real-world data on AAAs treated by AFX 2 endografts and followed for a long-term interval.International Registered Report Identifier (IRRID)PRR1-10.2196/16959

Initial Experience and Potential Advantages of AFX2 Bifurcated Endograft System: Comparative Case Series.

PurposeThe AFX2 endograft is a unibody, bifurcated stent graft that can be used to lower complications in certain patients. In this study, we retrospectively reviewed consecutive cases in which the AFX2 system was used to overcome the challenges of narrow distal aorta, as well as to reduce procedure time and contrast medium dose. Furthermore, we compared the results with matched patients treated using the Endurant II endograft system.Materials and MethodsThis was a retrospective observational study of nine patients with abdominal aortic aneurysm (AAA) who underwent endovascular aneurysm repair (EVAR) using the AFX2 device between June 2017 and April 2018 at Seoul National University Hospital. The patients had narrow distal aorta (n=3), reversed tapered neck (n=1), iliac artery aneurysm (n=2), chronic kidney disease patients (n=2), and impending rupture (n=1). Seven matched patients were treated using the Endurant II graft.ResultsIn the AFX2 group, the mean procedure time was 87.2 minutes, mean blood loss volume was 157.7 mL, and mean volume of contrast medium used was 48.3 mL. In the Endurant II group, the mean procedure time was 140.0 minutes, mean blood loss volume was 175.0 mL, and mean volume of contrast medium used was 119.3 mL.ConclusionOur preliminary experiences with selected AAA patients treated using the AFX2 endovascular repair system showed good outcomes compared with similar patients treated using the Endurant II system. Therefore, the AFX2 may be a good option to perform EVAR in patients of advanced age who have chronic kidney failure or narrow distal aorta.

Endovascular Repair of Aortoiliac or Common Iliac Artery Aneurysm Using the Lifetech Iliac Bifurcation Stent Graft System: A Prospective Multicenter Clinical Study

Sacrifice of the internal iliac artery (IIA) may result in ischemic manifestations after aortoiliac aneurysm (AIA) or common iliac artery aneurysm (CIAA) endovascular repair. This study sought to evaluate the safety and efficacy of a new Iliac Bifurcation Stent Graft (IBSG; Lifetech Scientific, Shenzhen, China) system for revascularization of the IIA. Patients who underwent implantation of the IBSG at 8 centers in China from September 2015 to June 2018 were enrolled. Clinical and computed tomography angiography follow-up assessments were conducted at 30 and 180days postoperatively. The primary end point was the IIA patency rate of the IBSG device at 180days postoperatively. Secondary end points comprised the postoperative technical success rate and clinical success rate at 30 and 180days. Descriptive statistics and the Clopper-Pearson exact method were used to analyze the data. Seventy-three patients (mean age, 69.6years; 91.8% men) were eligible for this trial, and 59 patients were eligible for primary effectiveness end-point analysis. AIA was present in 55 patients (75.34%) and CIAA in 18 patients (24.66%). The iliac artery aneurysms were unilateral in 69 patients (94.52%) and bilateral in 4 patients (5.48%). Overall technical success was 89.04% (65 of 73 patients). IIA patency at 180days was 96.61% (57 of 59 patients). Sexual dysfunction occurred in 1 patient (1.69%), and 2 patients (3.39%) experienced buttock claudication. There was no mortality, type III endoleak, stent migration, kinking, or fracture during the procedure and follow-up. The IBSG implantation system is a safe and effective technique for IIA preservation during AIA or CIAA endovascular repair. The high technical success rate, IIA patency rate, and low complication rate are promising. Follow-up will be continued for 5years to confirm the durability of the device.

Predisposing Factors for Migration of the Iliac Limb and Reintervention after Endovascular Abdominal Aortic Aneurysm Repair

Migration of the iliac limb after endovascular abdominal aortic aneurysm repair (EVAR) can result in type 1b and 3 endoleaks, which are relatively common causes of reintervention after EVAR. The aim of the present study was to investigate the factors influencing migration of the iliac limb and methods of treatment. From April 2012 to September 2017, 4 patients experienced migration of the iliac limb, requiring additional iliac stent graft implantation intraoperatively or at follow-up at our institute. Patient 1 was a 74-year-old man in whom preoperative computed tomography angiography (CTA) revealed a large aneurysm. The patient underwent EVAR with a bifurcated stent graft, and the left iliac stent graft migrated into the aneurysm sac. Patient 2 was a 53-year-old man in whom CTA revealed a large abdominal aortic aneurysm (AAA) involving the bilateral common iliac artery (CIA), with occlusion of the left hypogastric artery. An iliac stent graft was deployed to the right CIA to preserve the hypogastric artery. CTA, at 5 years of follow-up, showed migration of the right iliac limb and impending rupture. Patient 3 was a 61-year-old man with a ruptured AAA, and CTA revealed a large AAA and dilated CIA. The patient underwent EVAR with a bifurcated stent graft. Three years after EVAR, CTA showed that the right iliac limb migrated and kinked, with rupture of the stent graft. Patient 4 was an 80-year-old man with a ruptured AAA and aortocaval fistula. CTA revealed a large aneurysm involving the bilateral CIA. The patient underwent urgent EVAR with a bifurcated stent graft, and a cuff was deployed to seal the landing zone of the left CIA to preserve the hypogastric artery. Type 3 endoleak occurred because of the migration and detachment of the left iliac limb. All 4 patients underwent additional iliac stent graft implantation to connect or reline the iliac limb. The mean diameter of the aneurysms was 85.3±18.9mm, and 2 patients were diagnosed with ruptured AAAs. The mean diameter, length, and proportional engagement rate of the CIA that experienced migration of the iliac limb were 25.50±11.1mm, 32.8±6.6mm, and 72.75%±17.88%, respectively. Oversizing of the iliac stent graft was 10-20% in 2 patients and was less than 10% in the other 2 patients. The migrated iliac limbs were bell-bottom stent grafts. All patients underwent additional iliac stent graft implantation successfully, and there were no deaths or complications perioperatively. The patients were followed up from 7 months to 3 years and remained in good condition. Migration of the iliac limb after EVAR was influenced by a complex combination of several factors including a large aneurysm (>60mm in diameter), dilated or aneurysmal CIA (>18mm in diameter), short length of fixation (<70%), lower degree of iliac limb oversizing (<10-20%), and bell-bottom of the iliac limb. Patients with these factors require more vigorous surveillance after EVAR. The implantation of an additional stent graft is effective and is the most common reintervention procedure.