Open Conversion After Endovascular Aneurysm Sealing: Technical Features and Clinical Outcomes in 44 Patients.

PURPOSE: To evaluate the technical features and clinical results after open conversion for complications following endovascular aneurysm sealing (EVAS). MATERIALS AND METHODS: From July 2013 to February 2020, 44 patients (mean age 72±8 years; 36 men) underwent an open conversion due to EVAS complications in a single center. Data were collected on patient characteristics, reasons for conversion, characteristics and duration of the procedure, condition of the polymer, blood loss, time in the intensive care unit (ICU), and intra/postoperative complications. The main outcome measure was mortality at 30 days and in follow-up. Data are presented as the median (IQR) and absolute range. RESULTS: On average, the open conversion took place 3 years after the initial EVAS implantation [median 37 months (IQR 23, 50); range 0-64]. Most patients were converted due migration (82%), aneurysm growth (77%), and/or endoleak (75%), with 21 patients (48%) having all 3 events. Less frequent diagnoses were aneurysm rupture (n=7), aortic infection (n=3), technical failure during implantation (n=2), and graft thrombosis (n=1). The majority of patients (n=26) were asymptomatic and converted electively, but 9 were operated on urgently and 9 emergently (7 late rupture and 2 due to technical failure). The median procedure duration was 178 minutes (IQR 149, 223; range 87-417), the median blood loss was 1100 mL (IQR 600, 2600; range 300-5000). Polymer degradation was mentioned in the operative reports of 18 cases (41%). Patients stayed a median of 3 days (IQR 2, 7; range 1-35) in the ICU, while the median length of stay in the hospital was 14 days (IQR 10, 20; range 0-93). The 30-day mortality was 23% (n=10). During a median follow-up of 3 months (IQR 0, 11; range 0-38), no additional deaths occurred, but 12 patients suffered from an adverse event. There were 3 cases of wound dehiscence after laparotomy, 2 cases of leg ischemia, 2 cases of renal failure, and individual cases of urinary obstruction, urinoma, paralytic ileus, gastrointestinal bleeding, and postoperative delirium. A non-elective setting was associated with a significantly increased mortality of 33% in urgent cases and 56% in emergent cases (p=0.007). Based on these results an algorithm for the management of EVAS complications was developed. CONCLUSION: The significantly increased mortality associated with nonelective conversions highlights the need for active surveillance. The presented algorithm offers a structured tool to avoid emergency conversions.

Improved Remodeling With TEVAR and Distal Bare-Metal Stent in Acute Complicated Type B Dissection.

BACKGROUND: The ASSIST (A multicentre Study in Survivors of type B aortic dissection undergoing Stenting) study compared both 1-year outcomes and evolution of true and false lumen (eg, remodeling) in patients with complicated type B aortic dissection subjected to thoracic endovascular aortic repair (TEVAR) with distal true lumen scaffolding by self-expanding nitinol open stent in comparison with TEVAR alone. METHODS: The ASSIST study was a multicenter prospective single-arm study comparing clinical and imaging data from 39 consecutive patients (59.4 ± 13 years of age) who received TEVAR and the JOTEC E-XL open stent with data from matched control subjects treated with TEVAR alone based on 1:1 propensity score matching. Clinical data were collected by an independent Contract Research Organization (CRO) and computed tomography images were subjected to blinded core-lab analysis. RESULTS: There were no differences in baseline demographics, clinical profiles, morphological data, procedural details, and in-hospital and 1-year outcomes between groups. Differences emerged with regard to evolution of both true lumen distal to stent graft, false lumen over the entire length of dissection, and remodeling (P < .001). At 1 year, TEVAR with the E-XL stent revealed false lumen thrombosis at the level of celiac trunk in 53.8% vs 17.9% with TEVAR alone (P = .004). Kaplan-Meier survival analysis indicated favorable clinical outcomes with the additional E-XL stent. CONCLUSIONS: TEVAR for acute complicated type B aortic dissection proved to be safe and promoted remodeling of the stent grafted thoracic aorta. Additional scaffolding of the true lumen distal to TEVAR with a self-expanding stent supported distal true lumen expansion, false lumen regression, and thrombosis, with evidence of improved distal remodeling at 1 year.

Influence of the Revised Nellix Instructions for Use on Outcomes After Endovascular Aneurysm Sealing.

PURPOSE: To evaluate the impact of the revised Nellix instructions for use (IFU) from 2016 on clinical outcomes and anatomic applicability by retrospectively applying them to a cohort treated with endovascular aneurysm sealing according to the original IFU 2013. METHODS: A single-center study was conducted of 100 consecutive patients (mean age 72±8 years, range 46-91; 89 men) treated electively with standard bilateral EVAS from July 2013 to August 2015 and followed through December 2017. Procedures previously classified within and outside the original IFU from 2013 (75 and 25, respectively) were reclassified according to the revised IFU 2016 (34 and 66, respectively). Stepwise backward logistic regression analysis was performed to evaluate the prognostic value of specific anatomic features for the development of endoleak and/or migration. RESULTS: The single most important morphologic feature disqualifying patients from being within IFU 2016 was a thrombus ratio >1.4 (36 of 41 reclassified patients). Overall technical success was 98% (100% within vs 97% outside IFU 2016, p=0.323) and 30-day mortality was 3% (0% within vs 5% outside IFU 2016, p=0.251). During a median follow-up of 31 months (range 0-53), overall mortality was 21% (15% within vs 24% outside IFU 2016, p=0.469); aneurysm-related mortality was 8% (3% within vs 11% outside IFU 2016, p=0.533). Twenty-six patients developed an endoleak (6 within vs 20 outside IFU 2016, p=0.172) and 23 had migration (4 within vs 19 outside IFU 2016, p=0.088). Both proximal neck length <10 mm and neck angulation >60° were positive predictors for the development of endoleak and/or migration. A reintervention was performed in 26 patients (7 within vs 19 outside IFU 2016, p=0.376). While a significant difference was found between the within vs outside IFU 2016 groups with regard to freedom from migration (p=0.026) and the composite freedom from endoleak and/or migration (p=0.021), there were no significant differences in survival (p=0.201) or freedom from reintervention (p=0.505), suggesting a limited effectiveness of the new IFU 2016. CONCLUSION: The IFU 2016 reduced the anatomic applicability to 34% from 75% for the original IFU 2013. The lack of significant intergroup differences in terms of survival and reinterventions suggests a limited effectiveness of the new IFU 2016.

Anatomical Applicability of Endovascular Aneurysm Sealing Techniques in a Consecutive Cohort of Fenestrated Endovascular Aneurysm Repairs.

PURPOSE: To determine how many endovascular aneurysm sealing (EVAS) procedures with/without off-label use of chimneys (ChEVAS) could have been performed in a cohort of patients who had undergone fenestrated endovascular aneurysm repair (FEVAR). METHODS: Sixty patients (median age 76.3 years; 54 men) who underwent FEVAR in our institution between 2013 and 2015 were selected for the study. The median aneurysm diameter was 62.0 mm (interquartile range 59.3, 69.0). Preoperative computed tomography angiograms (CTA) were anonymized and sent to 2 physicians with experience of more than 40 ChEVAS interventions. These ChEVAS planners were blinded to the study purpose and asked to agree upon an EVAS/ChEVAS plan. The primary outcome was the percentage of the FEVAR patients in whom an EVAS/ChEVAS was technically possible. The secondary outcomes were a comparison of seal zones, number of target vessels, and device cost. RESULTS: An EVAS-based intervention would have been technically possible in 56 (93.3%) of the FEVAR patients. The median proximal aortic seal zone was significantly more distal in the EVAS/ChEVAS procedures vs the FEVAR cases (zone 8 vs zone 7, p<0.001) and fewer target vessels were involved (median 2 vs 3, p<0.001). The cost of the EVAS/ChEVAS device was 66% of the FEVAR device. Planners would not currently advocate an EVAS-based intervention in 43 (76.8%) of these 56 patients due to concerns regarding the risk of migration associated with the lumen thrombus ratios observed. CONCLUSION: EVAS is technically feasible in the majority of patients undergoing FEVAR in our institution but currently advocated in only 23.2%. The seal zone was more distal, fewer target vessels were involved, and the device cost was lower in the planned EVAS/ChEVAS interventions.

Endovascular Aneurysm Sealing (EVAS) and Chimney EVAS in the Treatment of Failed Endovascular Aneurysm Repairs.

PURPOSE: To assess the technical success and clinical outcome of reinterventions using the Nellix Endovascular Aneurysm Sealing (EVAS) System to treat complications after endovascular aneurysm repair (EVAR). METHODS: Fifteen consecutive patients (mean age 79 years; 14 men) with prior EVAR were treated with EVAS between March 2014 and December 2015 at 2 institutions. The failed prior EVARs included 13 bifurcated endografts, 1 bifurcated graft plus fenestrated cuff, and 1 tube endograft. Endoleaks were the predominant indications: type Ia in 10 and type III in 5 (3 type IIIa and 2 type IIIb). All patients presented with progressive aortic aneurysms (median 7.85-cm diameter; range 6.5-11). Eight patients were treated on an urgent or emergency basis (6 symptomatic aneurysms and 2 contained ruptures). All patients underwent Nellix relining of the failed stent-graft; 10 had chimney (Ch) procedures in combination with EVAS (chEVAS) because the proximal landing zones were inadequate. RESULTS: Technical success was 100%. All endoleaks were successfully sealed, and no additional intervention was required. No further endoleak after EVAS or chEVAS was recorded. Endobag protrusion occurred in 1 case without sequelae. One elderly patient with ruptured aneurysm died from multiple organ failure 2 months postoperatively. One renal artery guidewire injury led to nephrectomy because of active bleeding. No reinterventions, aneurysm-related mortalities, graft thrombosis, endoleaks, or chimney graft occlusions were observed during a median follow-up of 8 months (range 3-24). CONCLUSION: The present preliminary experience demonstrates that the use of EVAS/chEVAS is feasible for treatment of failed EVAR. This technique may be used as bailout or an alternative treatment when other established methods are infeasible or not available.

Treating iliac aneurysm using the Nellix Endovascular Sac Sealing System.

As endovascular treatment of abdominal aortic aneurysms has become established, there has been growing focus on treatment of the aneurysmal iliac artery. Isolated, large iliac aneurysms >30 mm pose a risk of rupture, but, in addition, 20% to 30% of abdominal aortic aneurysms are associated with iliac aneurysmal dilatation, which can compromise long-term outcomes. Endovascular solutions are evolving and until recently have utilized standard stent graft technology. The endovascular aortic sealing system was introduced as a new, effective method for the treatment of infrarenal aortic aneurysms. In this article, we present our recent extended use of the Nellix system, with or without a combination of adjuvant endovascular techniques, in the treatment of 84 common iliac artery aneurysms. The results support the use of endovascular aortic sealing system in endovascular therapy for aneurysmal iliac pathologies. Different endovascular sealing techniques for the treatment of common iliac artery aneurysms, re-interventions, and extended follow-up are also discussed.

Initial Experience in the Treatment of Extensive Iliac Artery Aneurysms With the Nellix Aneurysm Sealing System.

PURPOSE: To assess the feasibility and effectiveness of the Nellix prosthesis in the treatment of common iliac artery aneurysms. METHODS: Between May 2013 and June 2015, 230 patients underwent implantation of the Nellix device at 2 institutions. Fifty of these patients (mean age 76 years; 35 men) were identified as having 60 common iliac artery aneurysms (CIAAs) with a median diameter of 4 cm (range 3.5-7). The majority of patients had aortoiliac aneurysms (5, 70%), 10 (20%) had isolated CIAAs, and 5 (10%) had iliac anastomotic aneurysms after aortoiliac bypass. In 20 patients, the iliac aneurysm was the indication for the intervention; in the other 30 patients, the endovascular iliac repair was an adjunct procedure to endovascular aneurysm sealing (EVAS). An iliac branch device (IBD) was used when feasible to preserve flow to the internal iliac artery. RESULTS: Seventeen (34%) patients underwent elective implantation of the Nellix graft in combination with an IBD, 33 (66%) patients underwent Nellix sealing of the CIAA using 1 (n=5), 2 (n=22), or 3 Nellix grafts (2 bilateral grafts and 1 graft as an extension to the external iliac artery in 6 patients). The technical success rate was 100%, and no graft-related complications were reported postoperatively. No buttock claudication, reinterventions, graft thrombosis, or endoleaks were observed during a mean follow-up of 12 months. CONCLUSION: Our initial experience demonstrates that Nellix grafts are feasible and safe for the treatment of extensive iliac artery aneurysms. The long-term durability of these grafts should be validated in larger patient cohorts before this promising alternative endovascular technique can gain widespread acceptance.

Early experience with the new endovascular aneurysm sealing system Nellix: First clinical results after 50 implantations.

OBJECTIVE: In the present study, 50 EVAS procedures were evaluated in regard to primary (survival and technical success) and secondary (device-related complications) events of interest. METHODS: The single center study was conducted from July 2013 to August 2014 with prospective collection of the clinical data. The clinical results were controlled by CT angiography and contrast-enhanced ultrasound. RESULTS: The technical success was 98% and the 30-day mortality 4%. One (2%) patient died from multisystem organ failure and another patient from an intracranial bleeding, respectively. One patient (2%) suffered from a device-related aneurysm rupture. During early follow-up, one (2%) patient developed an endoleak type II, while three (6%) patients suffered from a partial endograft limb thrombosis. Overall, a secondary intervention was necessary in six (12%) patients. CONCLUSIONS: With the Nellix EVAS system, a high primary technical success of 98% was achieved; one (2%) patient developed an endoleak type II which did not require secondary intervention. Those promising results are contrasted by a substantial rate of endograft limb thromboses (8%) and one (2%) intraoperative aneurysm rupture. Further studies are needed to assess the durability of the Nellix stentgraft and the occurrence of device-related complications.

Clinical outcomes in hybrid repair procedures for pathologies involving the aortic arch.

OBJECTIVE: Fifty patients with complex aortic disease, who received hybrid treatment of the aortic arch with supra-aortic debranching and endovascular stent-graft repair, were evaluated in regard to events of primary (survival and technical success) and secondary (procedure-related complications) interest. METHODS: The single-center study was conducted over an eight-year period from December 2004 to December 2012. Treated medical conditions included 23 aortic aneurysms (46%), 21 aortic dissections (42%), and six penetrating aortic ulcers (12%). Procedures were divided into groups of elective, urgent, and emergent. RESULTS: Twenty-eight (56%) patients were operated electively, 15 (30%) urgently, and seven (14%) emergently. Sternotomy, cardiopulmonary bypass, and deep hypothermic circulatory arrest were required in 12 (24%) patients. The primary technical success rate was 86% and raised to 92% (n=46) of secondary technical success rate after therapy of three type I endoleaks. The 30-day mortality added up to 16.0%, and the mean time of survival was 49.3 months. In a total of eight (16%) patients, an endoleak occurred (five endoleaks type I, three endoleaks type II), while nine (18%) of patients suffered a perioperative stroke. CONCLUSIONS: In severely ill patients with complex aortic diseases, hybrid therapy may offer a promising alternative to conventional open repair.