Failure mode analysis of the Endologix endograft.

Type III (T-III) endoleaks following endovascular aneurysm repair (EVAR) remain a major concern. Our center experienced a recent concentration of T-III endoleaks requiring elective and emergency treatment and prompted our review of all EVAR implants over a 40-month period from April 2011 until August 2014. This report represents a single center experience with T-III endoleak management with analysis of factors leading to the T-III-related failure of EVAR. A retrospective review of all the operative reports, medical records, and computed tomography scans were reviewed from practice surveillance. Using Society for Vascular Surgery aneurysm reporting standards, we analyzed the morphology of the aneurysms before and after EVAR implant using computed tomography. Index procedure and frequency of reinterventions required to maintain aneurysm freedom from rupture were compared across all devices using SAS v 9.4 (SAS Institute, Inc, Cary, NC). Major adverse events (MAEs) requiring secondary interventions for aneurysm treatment beyond primary implant were analyzed for methods of failure. Aneurysm morphology of patients requiring EVAR was compared across all endograft devices used for repair. For purposes of MAE analysis, patients receiving Endologix (ELX) endograft were combined into group 1; Gore, Cook, and Medtronic endograft patients were placed into group 2. Overall, technical success and discharge survival were achieved in 97.3% and 98% of patients regardless of device usage. There was no significant device related difference identified between patient survival or freedom from intervention. MAEs involving aneurysm treatment were over seven-fold more frequent with ELX (group 1) vs non-ELX (group 2) endografts (P < .01). Group 1 patients with aneurysm diameters larger than 65 mm were associated with a highly significant value for development of a T-III endoleak (odds ratio, 11.16; 95% confidence interval, 2.17, 57.27; P = .0038). While EVAR technical success and survival were similar across all devices, ELX devices exhibited an unusually high incidence of T-III endoleaks when implanted in abdominal aortic aneurysms with a diameter of more than 65 mm. Frequent reinterventions were required for Endologix devices for prevention of aneurysm rupture due to T-III endoleaks.

Lemmon GW ，Motaganahalli RL ，Chang T ，Slaven J ，Aumiller B ，Kim BJ ，Dalsing MC ... -  《-》

Fourteen-year outcomes of abdominal aortic endovascular repair with the Zenith stent graft.

Long-term results of abdominal aortic aneurysm (AAA) endovascular repair are affected by graft design renewals that tend to improve the performance of older generation prostheses but usually reset the follow-up times to zero. The present study investigated the long-term outcomes of endovascular AAA repair (EVAR) using the Zenith graft, still in use without major modification, in a single center experience. Between 2000 and 2011, 610 patients underwent elective EVAR using the Zenith endograft (Cook Inc, Bloomington, Ind) and represent the study group. Primary outcomes were overall survival, freedom from AAA rupture, and freedom from AAA-related death. Secondary outcomes included freedom from late (>30 days) reintervention, freedom from late (>30 days) conversion to open repair, freedom from aneurysm sac enlargement >5.0 mm and freedom from EVAR failure, defined as a composite of AAA-related death, AAA rupture, AAA growth >5 mm, and any reintervention. Mean age was 73.2 years. Mean aneurysm diameter was 55.3 mm. There were five perioperative deaths (0.8%) and three intraoperative conversions. At a mean follow-up of 99.2 (range, 0-175) months, seven AAA ruptures occurred, all fatal except one. Overall survival was 92.8% ± 1.1% at 1 year, 70.1% ± 1.9% at 5 years, 37.8% ± 2.9% at 10 years, and 24 ± 4% at 14 years. Freedom from AAA-rupture was 99.8% ± 0.02 at 1 year (one case), 99.4% ± 0.04 at 5 years (three cases), and 98.1% ± 0.07 at 10 and 14 years. Freedom from late reintervention and conversion was 98% ± 0.6 at 1 year, 87.7% ± 1.5 at 5 years, 75.7% ± 3.2 at 10 years, and 69.9% ± 5.2 at 14 years. Freedom from aneurysm sac growth >5.0 mm was 99.8% at 1 year, 96.6% ± 0.7 at 5 years, 81.0% ± 3.4 at 10 years, and 74.1% ± 5.8% at 14 years. EVAR failure occurred in 132 (21.6%) patients at 14 years. At multivariate analysis, independent predictors of EVAR failure resulted type I and III endoleak (hazard ratio [HR], 6.7; 95% confidence interval [CI], 4.6- 9.7; P < .001], type II endoleak (HR, 2.3; 95% CI, 1.6-3.4; P < .001), and American Society of Anesthesiologists grade 4 (HR, 1.6; 95% CI, 1.0-2.6; P = .034). EVAR with Zenith graft represents a safe and durable repair. Risk of rupture and aneurysm-related death is low, whereas overall long-term survival remains poor. Novel endograft models should be tested and evaluated considering that one-fourth of the operated patients will still be alive after 14 years.

Verzini F ，Romano L ，Parlani G ，Isernia G ，Simonte G ，Loschi D ，Lenti M ，Cao P ... -  《-》

Results of standard suprarenal fixation endografts for abdominal aortic aneurysms with neck length ≤10 mm in high-risk patients unfit for open repair and fenestrated endograft.

The aim of this study was to evaluate long-term outcomes of endovascular aneurysm repair (EVAR) using a standard suprarenal fixation endograft in abdominal aortic aneurysms (AAAs) with infrarenal neck length ≤10 mm (short-neck AAA [SN-AAA]). From 2005 to 2010, data of high-risk patients with SN-AAA, unfit for open repair (OR) and fenestrated EVAR, were prospectively collected. Follow-up was performed by duplex ultrasound and contrast-enhanced ultrasound or computed tomography angiography at 1 month, 6 months, and 12 months and yearly thereafter. The primary end point was AAA-related mortality. Secondary end points were proximal type I endoleak, freedom from reintervention, and AAA shrinkage (>5 mm). Sixty patients (mean age, 74.9 ± 6.2 years; American Society of Anesthesiologists class 3 [85%] and class 4 [15%]) were enrolled. The mean aneurysm diameter and neck length and diameter were 60.4 ± 12.2 mm, 8.4 ± 1.6 mm, and 23.5 ± 3 mm, respectively. Four (7%) patients were symptomatic and 15 (25%) had rapid AAA enlargement (>5 mm/6 months). Cook Zenith Flex (Cook Medical, Bloomington, Ind) endografts (32) and Medtronic Endurant (Medtronic, Santa Rosa, Calif) endografts (28) were implanted. The mean follow-up was 51 ± 18 months. Survival at 5 years was 70%. There were three (5%) type I endoleaks. One was sealed by endovascular reintervention, and two (3%) underwent conversion to OR for AAA rupture at 8 and 36 months. Both patients died (2/60; 3% AAA-related mortality). Reinterventions were necessary for another five (8%) patients, and they were not proximal neck related. Freedom from reintervention at 5 years was 90%. In 49 (82%) cases, there was AAA shrinkage; the AAA diameter remained stable in nine (15%) and increased in two (3%) cases. Severe proximal angle (α neck angle ≥60 degrees) was associated with type I endoleak (P = .010) and reinterventions (P = .010). The neck length <7 mm (P = .030) was associated with reinterventions (P = .017). Suprarenal fixation EVAR in SN-AAA with a straight, not wide neck and 7- to 10-mm aortic neck length can be considered safe and effective in patients who are unfit for OR and fenestrated EVAR. For these cases, long-term data showed acceptable results in preventing aneurysm rupture and related mortality.

Gallitto E ，Gargiulo M ，Freyrie A ，Bianchini Massoni C ，Pini R ，Mascoli C ，Faggioli G ，Stella A ... -  《-》

Natural history of gutter-related type Ia endoleaks after snorkel/chimney endovascular aneurysm repair.

Alternative endovascular strategies using parallel or snorkel/chimney (chimney endovascular aneurysm repair [ch-EVAR]) techniques have been developed to address the lack of widespread availability and manufacturing limitations with branched/fenestrated aortic devices for the treatment of complex abdominal aortic aneurysms. Despite high technical success and midterm patency of snorkel stent configurations, concerns remain regarding the perceived increased incidence of early gutter-related type Ia endoleaks. We aimed to evaluate the incidence and natural history of gutter-related type Ia endoleaks following ch-EVAR. Review of medical records and available imaging studies, including completion angiography and serial computed tomographic angiography, was performed for all patients undergoing ch-EVAR at our institution between September 2009 and January 2015. Only procedures involving ≥1 renal artery with or without visceral snorkel stents were included. Primary outcomes of the study were presence and persistence or resolution of early gutter-related type Ia endoleak. Secondary outcomes included aneurysm sac shrinkage and need for secondary intervention related to the presence of type Ia gutter endoleak. Sixty patients (mean age, 75.8 ± 7.6 years; male, 70.0%) underwent ch-EVAR with a total of 111 snorkel stents (97 renal [33 bilateral renal], 12 superior mesenteric artery, 2 celiac). A mean of 1.9 ± 0.6 snorkel stents were placed per patient. Early gutter-related type Ia endoleaks were noted on 30.0% (n = 18) of initial postoperative imaging studies. Follow-up imaging revealed spontaneous resolution of these gutter endoleaks in 44.3%, 65.2%, and 88.4% of patients at 6, 12, and 18 months postprocedure, respectively. Long-term anticoagulation, degree of oversizing, stent type and diameter, and other clinical/anatomic variables were not significantly associated with presence of gutter endoleaks. Two patients (3.3%) required secondary intervention related to persistent gutter endoleak. At a mean radiologic follow-up of 20.9 months, no difference in mean aneurysm sac size change was observed between those with or without early type Ia gutter endoleak (-6.1 ± 10.0 mm vs -4.9 ± 11.5 mm; P = .23). Gutter-related type Ia endoleaks represent a relatively frequent early occurrence after ch-EVAR, but appears to resolve spontaneously in the majority of cases during early to midterm follow-up. Given that few ch-EVAR patients require reintervention related to gutter endoleaks and the presence of such endoleak did not correlate to increased risk for aneurysm sac growth, its natural history may be more benign than originally expected.

Ullery BW ，Tran K ，Itoga NK ，Dalman RL ，Lee JT ... -  《-》

Type II endoleaks after endovascular repair of abdominal aortic aneurysms: fate of the aneurysm sac and neck changes during long-term follow-up.

Nolz R ，Teufelsbauer H ，Asenbaum U ，Beitzke D ，Funovics M ，Wibmer A ，Plank C ，Prusa AM ，Lammer J ，Schoder M ... -  《-》