Coupling bifurcated stent-grafts to overcome anatomic limitations of endovascular repair of abdominal aortic aneurysms.

To evaluate the effectiveness of the coupling stent-graft technique and outcomes on contrast-enhanced computed tomography (CT). All patients who underwent endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAAs) between 2007 and 2010 at a single institution were retrospectively analyzed. Of the 161 cases, 19 patients who had coupling stent-grafting because of AAA proximal neck angulation greater than 60°, conical neck, or iliac tortuosity were included. Patient age ranged from 62 to 87 years (mean, 73.3 y). Mean follow-up was 18.7 months (range, 1-36 mo). The coupling stent-graft technique was defined by the use of suprarenal fixation device main bodies (Zenith or Talent) with one or more EXCLUDER limbs to adapt tortuous and angulated iliac arteries. Pretreatment contrast-enhanced CT was analyzed based on three-dimensional and multiplanar reformatted images. Follow-up contrast-enhanced CT was also analyzed. Mean aneurysm diameter was 68.9 mm ± 14.0, neck length was 32.7 mm ± 15.1, and neck angulation was 68.9° ± 11.5. Conical neck shapes were present in four patients (21.1%) and ruptured AAAs were present in two (10.5%). Among 38 iliac arteries, the mean iliac artery tortuosity index was 1.52 ± 0.27 and iliac angle was 106.8° ± 18.1. Three patients (15.8%) underwent repeat intervention: placement of a balloon-expandable stent in the proximal neck for type I endoleak (n = 1), endovascular embolization for proximal type I endoleak (n = 1), and percutaneous approach following endovascular embolization for type II endoleak (n = 1). No type III endoleak, limb occlusion, limb kinking, or stent-graft migration developed. The coupling stent-graft technique is technically feasible, with acceptable midterm outcomes in EVAR of AAA in patients with unfavorable neck and iliac anatomies.

Lee M ，Lee DY ，Kim MD ，Lee MS ，Park SI ，Won JY ，Choi D ，Ko YG ... -  《-》

The Relationship between Temporal Changes in Proximal Neck Angulation and Stent-Graft Migration after Endovascular Abdominal Aortic Aneurysm Repair.

In recent years, endovascular abdominal aortic aneurysm repair (EVAR) for treating abdominal aortic aneurysms (AAA) has become quite prevalent in Japan. Though little information is available about temporal changes in proximal neck angulation due to the difficulties encountered in measuring the angle. Therefore, we examined temporal changes in proximal neck angulation and its relationship to stent-graft migration after EVAR. Between June 2007 and March 2010, 159 patients underwent EVAR for treatment of fusiform AAAs at our hospital. This study focuses on the 80 patients among this group whose treatment sites and subsequent stent grafts were examined by contrast computed tomographic angiography before surgery, directly after surgery (within 4 days), as well as 1 year and 2 years thereafter. We created curved planar reconstruction (CPR) images and measured the length of migration and neck angle using our method. At 2 years after EVAR, the average length of proximal landing zone was 21.4 ± 9.2 mm. The average length of stent migration after 2 years was 1.41 ± 2.68 mm. The average neck angle was 33.9° preoperatively and 29.9° directly after surgery yielding a significant difference. However, 1 and 2 years after surgery the average neck angle was 28.2° and 28.4°, respectively. The number of patients experiencing a change >6° in the angle of the proximal neck between the preoperative condition and that directly after surgery was 16 (34.8%) with the use of Zenith stent grafts (n = 46) and 14 (41.2%) with the use of Excluder stent grafts (n = 34). There was no correlation between the proximal neck angle and migration of the proximal stent graft. In addition, there was no correlation between the changes in proximal neck angle and the secondary intervention rate and the occurrence of endoleak. There was a significant change in the neck angle between the preoperative condition and the immediate postoperative condition. However, there was no clear relationship found between the angle of the neck and the proximal stent-graft migration. Postoperative changes in the proximal neck angle just after EVAR and subsequent temporal changes during a 2-year follow-up period do not appear to predict stent-graft migration, secondary intervention rates, or the occurrence of endoleak.

Tokunaga S ，Ihara T ，Banno H ，Kodama A ，Sugimoto M ，Komori K ... -  《-》

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 ± 18.9 mm, 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 ± 11.1 mm, 32.8 ± 6.6 mm, 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 (>60 mm in diameter), dilated or aneurysmal CIA (>18 mm 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.

Wang Y ，Li C ，Xin H ，Li J ，Wang H ... -  《-》

Anatomic feasibility of endovascular treatment of abdominal aortic aneurysms in emergency in the era of the chimney technique: impact on an emergency endovascular kit.

Despite promising results, endovascular aortic repair (EVAR) of ruptured/painful abdominal aortic aneurysms (RPAAA) continues to have limited use due to anatomic constraints linked to RPAAA morphology. Currently, EVAR for RPAAA is reserved for patients presenting with a long infrarenal aortic neck, because commercially available fenestrated stent grafts are not available in an emergency setting. Recently, the chimney technique (ChT) has been utilized to treat infrarenal abdominal aortic aneurysms (AAA) with short necks, but this technique requires specific materials. The aim of this study was to determine the rate of RPAAA eligible for EVAR since the advent of the ChT and to ascertain the standard materials needed in this context. We carried out a retrospective study of patients operated on for RPAAA (<24 hours after admission) at our center between 2006 and 2011. Patients' computed tomography (CT) scans were analyzed by two independent operators using 3-dimensional reconstruction software with a centerline of flow. To perform standard EVAR, the anatomic criteria used were those provided by the manufacturer (proximal neck diameter 18-32 mm with length >15 mm, angulation <60°, iliac diameter >7 mm). ChT anatomic feasibility criteria were: (1) a healthy aortic area >15 mm between the renal arteries and celiac trunk; (2) caudal orientation of renal arteries; and (3) a healthy descending thoracic aorta. Patients were classified according to the feasibility or nonfeasibility of standard EVAR and ChT. In total, over the period of study, 55 patients were operated on for RPAAA. In 5 patients (9%), CT scan quality was unsatisfactory and thus 50 patients (mean age 76 years, 75% men) were analyzed. Among them, 35 (70%) had a ruptured aneurysm and 17 (34%) were unstable. Anatomically, 22 (44%) patients were eligible for standard EVAR. Taking the ChT into consideration, an additional 11 (22%) patients were eligible for EVAR. Among these EVAR-eligible patients, mean proximal neck diameter was 23 ± 3 mm and stent grafts with 24-, 28-, and 32-mm diameters could fit in 33% (11 of 33), 51% (17 of 33), and 12% (4 of 33) of the cases, respectively. These results enabled us to determine the material that should be made available in the emergency setting in centers treating RPAAA. Among the 17 patients who were not eligible for EVAR, an iliac pathology (calcifications, stenosis) and a very hostile proximal neck (angulation, thrombus), respectively, were involved in 88% (15 of 17) and 12% (2 of 17) of the cases. The ChT increases EVAR feasibility by 50% in RPAAA. Taking into consideration our results, we recommend continued availability of emergency kits, including suitable aortouni-iliac stent grafts and basic material for performing ChT to allow surgeons to provide EVAR to the greatest number of RPAAA cases.

Brossier J ，Coscas R ，Capdevila C ，Kitzis M ，Coggia M ，Goeau-Brissonniere O ... -  《-》

Initial single-center experience with the Ovation stent-graft system in the treatment of abdominal aortic aneurysms: application to challenging iliac access anatomies.

To present our preliminary results with the Ovation(™) abdominal stent-graft system in abdominal aortic aneurysms (AAA) with narrow (≤7 mm) or angulated iliac vessels. From April 2012 to January 2014, 42 patients (97% men; mean age, 71 years; range, 55-89 years) with AAAs of 55.5 mm (50-79 mm) were treated with the Ovation device. Primary end points included technical success and freedom from early secondary interventions, any type of endoleak, and aneurysm-related death. Limb occlusion was studied with respect to iliac access diameter and angulation. Iliac angulation between 90° and 120° or <90° was considered moderate or severe, respectively. The postoperative follow-up was 7.8 ± 4.6 months (mean ± standard deviation). Infrarenal neck angulation was 26° ± 26°. AAA neck length and diameter were 27.3 ± 10.5 and 24.1 ± 3.2 mm, respectively. Forty-five percent of patients had at least 1 vessel of ≤7-mm diameter, and almost half of patients (24 of 44) had at least 1 iliac artery of moderate or severe angulation. Technical and treatment success were 100% and 95%, respectively. No stent-graft migration or type I, III, or IV endoleaks occurred. Type II endoleaks were identified in 5 patients, leading to sac enlargement in 2 and necessitating an embolization attempt that was unsuccessful in 1 case. No limb occlusion occurred, irrespective of the iliac diameter or angulation. Our 1-year results of the Ovation stent-graft system demonstrate excellent safety and effectiveness. The easy navigation through highly angulated and stenosed iliac vessels ensures high technical success in cases of challenging iliac anatomy. Follow-up is ongoing.

Trellopoulos G ，Georgakarakos E ，Pelekas D ，Papachristodoulou A ，Kalaitzi A ，Asteri T ... -  《-》