Impact of bridging stent design and configuration on branch vessel durability after fenestrated endovascular repair of complex aortic aneurysms.

OBJECTIVE: The ideal mating stent for target vessel revascularization in fenestrated endovascular aneurysm repair (FEVAR) of juxtarenal and thoracoabdominal aortic aneurysms remains unknown. The objective of this study was to assess the outcomes associated with use of different stent types and configurations mated with reinforced fenestrations during FEVAR. METHODS: Clinical data from patients undergoing FEVAR for juxtarenal and thoracoabdominal aortic aneurysms in a prospective physician-sponsored investigational device exemption trial were analyzed. Outcomes for two different balloon-expandable covered stents (BECSs) mated with reinforced fenestrations were assessed along with the impact of distal extension with a self-expanding stent (SES). Primary patency, branch-related endoleak, and reintervention rates were determined. Cox proportional hazards model was used for time-to-event analysis. RESULTS: From 2001 to 2016, there were 918 patients who underwent fenestrated or branched endograft repair of complex aortic aneurysms; 1604 renal arteries (RAs), 714 superior mesenteric arteries (SMAs), and 333 celiac arteries (CAs) were mated with reinforced fenestrations using JOMED (n = 2014; Abbott Vascular, Santa Clara, Calif) or iCAST (n = 637; Atrium Medical, Hudson, NH) BECSs. The type of BECS did not affect short-term or long-term patency, branch-related endoleaks, or reintervention rates in the RA, SMA, or CA. Twenty-five percent (402/1604) of RAs, 84% (598/714) of SMAs, and 8% (27/333) of CAs underwent distal SES extension at the index operation. RAs with a distal SES in addition to the BECS had a higher likelihood of an occlusion event (hazard ratio, 2.791; 95% confidence interval, 1.42-5.48; P = .003) and reinterventions (P = .036) compared with those without an SES. Addition of a distal SES to the BECS in the SMA or CA did not have an impact on patency or reintervention rates. CONCLUSIONS: BECS choice does not appear to have an impact on branch durability after FEVAR. Selective distal SES placement in RAs with high-risk anatomy does not appear to significantly protect against an occlusion event or to prevent secondary interventions. Routine addition of a distal SES does not improve SMA fenestration durability.

Incidence and management of iliac artery aneurysms associated with endovascular treatment of juxtarenal and thoracoabdominal aortic aneurysms.

BACKGROUND: This study reports the clinical impact of iliac artery aneurysms (IAAs) in a population of patients with juxtarenal and thoracoabdominal aortic aneurysms being treated with fenestrated or branched aortic endografts. METHODS: Data from 364 patients with IAA (33%) were extracted from the 1118 patients treated for juxtarenal or thoracoabdominal aortic aneurysms with a fenestrated or branched aortic endograft in a physician-sponsored investigational device exemption trial (2001-2016). IAAs were defined as ≥21 mm in diameter, as measured by an imaging core laboratory. Outcomes were assessed by univariate and multivariable analysis. RESULTS: IAAs were unilateral in 219 (60%) and bilateral in 145 (40%) of the 364 patients. Treatment was iliac leg endoprosthesis without coverage of the hypogastric artery (seal distal to the IAA in the common iliac artery), placement of a hypogastric branched endograft in 105 (21%), and hypogastric artery coverage with extension into the external iliac artery in 103 (20%); 67 (13%) were untreated. Procedure duration was longer for those with IAA (5.3 ± 1.79 hours vs 4.6 ± 1.74 hours; P < .001), although hospital stay was not. There was no difference in aneurysm-related mortality and all-cause mortality for patients with unilateral and bilateral IAAs compared with those without an IAA. Treatment of patients with a hypogastric branched endograft had similar all-cause mortality compared with treatment of patients without a hypogastric branched endograft but also with an IAA. Reintervention rates were significantly higher in those with bilateral IAAs compared with no IAA (hazard ratio, 1.886; P < .001). Spinal cord ischemia trended higher in patients with bilateral IAA. CONCLUSIONS: IAA management at the time of fenestrated or branched endovascular aneurysm repair increases procedure time without increasing hospitalization. The reintervention rate and spinal cord ischemia rate are higher in patients with bilateral IAA compared with those with no IAA.

Survival affects decision making for fenestrated and branched endovascular aortic repair.

OBJECTIVE: Repair options for complex abdominal and thoracoabdominal aortic aneurysms (TAAAs) are evolving with increased experience and availability of less invasive endovascular techniques. Identifying risk factors for mortality after fenestrated and branched endovascular aortic repair (F/B-EVAR) could improve patient selection and facilitate decision making regarding who may benefit from prophylactic F/B-EVAR. METHODS: We evaluated 1091 patients in a prospective investigational device exemption trial who underwent F/B-EVAR from August 2001 to June 2015 for complex aortic aneurysms (CAAs). Multivariable analysis of risk factors for death was performed using a nonproportional hazards model and a nonparametric analysis using random survival forest technology. RESULTS: Operative mortality after F/B-EVAR was low (3.7%), with high CAA-related survival at 30 day and 5 years (96.8% and 94.0%, respectively). All-cause 5-year survival, however, was 46.2% and older age, heart failure, chronic obstructive pulmonary disease, renal disease, anemia, and coagulation disorders were risk factors. Risk was highest for those undergoing type I/II TAAA repairs and those with larger aneurysms. CONCLUSIONS: Patients with multiple comorbidities and those undergoing type I or II TAAA repair are at greatest risk of mortality; however, in this high-risk population, F/B-EVAR offers greater survival compared with that reported for the natural history of untreated aneurysms. Operative and early mortality is lower than the best-reported open repair outcomes, even in this high-risk population, suggesting a potential benefit in extending the use of F/B-EVAR to low-to-average risk CAA patients.

Management of failed endovascular aortic aneurysm repair with explantation or fenestrated-branched endovascular aortic aneurysm repair.

OBJECTIVE: The incidence of failed endovascular aneurysm repair (EVAR) is increasing, and understanding the different methods of management and repair is paramount. The objective of this study was to evaluate the clinical management and rescue of failed EVAR by either explantation or fenestrated-branched EVAR (F/B-EVAR). METHODS: A retrospective analysis (1999-2016) of 247 patients who underwent either explantation (n = 162) or F/B-EVAR (n = 85) for failed EVAR was performed. F/B-EVAR was performed under a physician-sponsored investigational device exemption. Demographics of the patients, clinical presentation and failure etiology, perioperative management, rate of reinterventions, morbidity, and mortality were analyzed. Those undergoing surgical explantation were compared with those undergoing F/B-EVAR conversion. Statistical analysis included multivariable logistic regressions, Fisher exact test, and χ2 test. RESULTS: The majority of patients were male (n = 216 [87%]), with a mean age of 75 years (range, 50-93 years). The mean time from primary EVAR was higher in F/B-EVAR (46 ± 7 months vs 69 ± 41 months; P < .001). Graft manufacturer did not differ between those requiring explantation and those having endovascular rescue (P = .170). All emergencies (n = 24 [10%]) and infections (n = 28 [11%]) were treated with open conversion. Endoleak was the most common reason for failure in both explantation and F/B-EVAR groups (75% vs 64%, respectively; P = .052). Type I endoleak was the most common endoleak reported in both groups, occurring more frequently in F/B-EVAR (64% vs 40%; P < .001); type II endoleak was more common in those undergoing open repair (28% vs 2%; P < .001). Graft migration (12% vs 26%; P = .005) and neck degeneration/disease progression (14% vs 59%; P < .001) were more prevalent in F/B-EVAR, but aneurysm enlargement was more common in explantation (68% vs 33%; P < .001). Thirty-day reintervention rates did not differ between F/B-EVAR and explantation (odds ratio, 0.6258; 95% confidence interval, 0.2-1.86; P = .4115); however, 30-day mortality was lower in the F/B-EVAR group (5% vs 10%; P = .0192). Similarly, aneurysm-related mortality was also lower in the F/B-EVAR group (hazard ratio, 0.0683; 95% confidence interval, 0.01-0.44; P = .0048). A subset analysis excluding emergencies and infections did not alter the lack of difference in terms of freedom from reinterventions (P = .1175), 30-day mortality (P = .6329), or aneurysm-related mortality (P = .7849). CONCLUSIONS: Explantation and F/B-EVAR are necessary options in treating patients with failed EVAR, and both techniques have competitive results. Different modes of failure may point to a preferred method of treatment; consequently, rescue of failed EVAR should be individualized according to each patient's presentation and resources available.

Durable outcomes of thoracic endovascular aortic repair with Zenith TX1 and TX2 devices.

OBJECTIVE: Long-term data regarding the safety and durability of thoracic endovascular aortic repair (TEVAR) are limited. The study objective was to evaluate the long-term outcomes of TEVAR in high-risk patients with descending thoracic aortic pathology. METHODS: High-risk patients were treated with thoracic endografts (2001-2011) under a prospective, physician-sponsored, investigational device exemption trial. Three-dimensional reconstructions and measurements were performed on computed tomography scans acquired before discharge, at 1, 6, and 12 months, and then yearly thereafter. RESULTS: The study included 200 patients, of whom 171 were treated for thoracic aneurysm, 28 for chronic dissection, and 1 for aortobronchial fistula. Patients were monitored for an average of 4.8 ± 3.3 years, and 93 (46.5%) were monitored for >5 years. Operative mortality was 6.5%. Survival at 30 days and at 1, 5, and 9 years was 94.0%, 85.8%, 55.6%, and 31.4%, and freedom from aneurysm-related death was 94.0%, 92.4%, 91.7%, 91.7%, respectively. Sixty-one endoleaks occurred in 54 patients (28%). Sixty-seven reinterventions were performed in 50 patients. Overall freedom from reintervention at 30 days, 1, 5, and 9 years was 87.9%, 82.9%, 75.5%, and 64.0%, respectively. Forty-seven reinterventions (70%) were thoracic aneurysm-related, 35 (74%) of which were endovascular procedures. Thirty of these were to correct endoleaks at a median of 1.4 years (interquartile range, 0.2-5.0 years). CONCLUSIONS: TEVAR is durable and associated with high long-term aneurysm-related survival. Long-term imaging follow-up remains critical to identify endoleaks or rare device durability issues, most of which can be monitored or managed with endovascular therapies.

Durability of iliac artery preservation associated with endovascular repair of infrarenal aortoiliac aneurysms.

OBJECTIVE: This study evaluated and compared the long-term clinical outcomes of endovascular repair of infrarenal aortoiliac aneurysms (EVAR) vs EVAR with preservation of antegrade internal iliac artery (IIA) perfusion using iliac branched devices (EVAR-IBDs). METHODS: From October 1998 to August 2015, patients with infrarenal aortoiliac aneurysmal (AIA) disease at high risk for conventional open surgery were enrolled in a prospective physician-sponsored investigational device exemption trial. Clinical data of 75 patients treated with EVAR-IBD and 255 with standard EVAR were analyzed. Technical success, perioperative outcomes, mortality, device patency, endoleak rates, and reinterventions during a follow-up of 10 years were analyzed. RESULTS: There were 87 IBDs deployed in 75 patients. Technical success rate was 97%. Mortality at 30 days was 1.3%. Freedom from aneurysm-related mortality at 3, 5, and 10 years was 99%. Freedom from a type I or III endoleak at 3, 5, and 10 years was 99%. Freedom from secondary reinterventions at 3, 5, and 10 years was 86%, 81%, and 81%, respectively. Primary patency of the IBDs at 3, 5, and 10 years was 94%, 94%, and 77%, respectively. Twenty-four percent of patients underwent EVAR for concomitant AIA disease (EVAR-AIA), and 78% were managed by staged IIA embolization before EVAR. No statistically significant difference in freedom from aneurysm-related mortality, limb occlusions, or endoleak rates was identified in patients with EVAR-AIA vs EVAR-IBD (P > .05). There were significantly more secondary reinterventions in the EVAR-AIA group compared with the EVAR-IBD group (hazard ratio, 0.476, 95% confidence interval, 0.226-1.001; P = .045). CONCLUSIONS: EVAR of infrarenal AIAs with preservation of antegrade flow to the IIA using IBDs is feasible with long-term sustained durability. Serious considerations should be given to the use of IBDs in patients with infrarenal AIAs meeting appropriate anatomic criteria.

Preoperative Hypoalbuminemia is a Risk Factor for Early and Late Mortality in Patients Undergoing Endovascular Juxtarenal and Thoracoabdominal Aortic Aneurysm Repair.

BACKGROUND: Advances in endovascular aneurysm repair now allow surgeons to treat high-risk patients with complex aortic aneurysms. Stringent selection criteria for repair exist from an anatomic and technical perspective; however, there is a paucity of literature examining frailty in patients being evaluated for fenestrated and branched endovascular aortic repair (FEVAR). As a marker of frailty well supported in the literature, we hypothesized that preoperative hypoalbuminemia would increase risk for short-term mortality after endovascular juxtarenal and thoracoabdominal aortic aneurysm repair. METHODS: One thousand eighty nine consecutive patients with juxtarenal and thoracoabdominal aortic aneurysms considered high risk for open surgery from a single institution who underwent FEVAR from 2001 to 2014 were included in the study. Risk factors for all-cause mortality were identified via a Cox regression model on time to death. RESULTS: The patients with severe hypoalbuminemia (albumin <2.4 g/dL) had significantly increased 30-day mortality (P = 0.025, odds ratio [OR]: 4.967 (95% CI: 1.385-17.814, normal versus severe) and 2-year mortality P = 0.006, OR: 2.4, 95% CI: 1.05-5.73, normal versus severe), as well as increased 30-day complication rates P = 0.026, OR: 1.91, 95% CI: 0.9-4.17, normal versus severe). A univariate analysis for 30-day mortality revealed no significant difference in median age: 75.1 vs. 72.5 years (alive at 30 days (Q1, Q3: 69.8, 80.1) versus expired (Q1, Q3: 69.3, 77.8), P = 0.24. CONCLUSIONS: Patients with hypoalbuminemia have significantly increased mortality risk. Albumin level is regulated by nutritional intake and inflammation due to chronic disease, which make it a useful part of a preoperative frailty assessment. Further studies are needed to identify whether optimizing nutrition status will affect albumin levels or decrease mortality.

Impact of alterations in target vessel curvature on branch durability after endovascular repair of thoracoabdominal aortic aneurysms.

OBJECTIVE: The aim of this study was to evaluate curvature and its effect on the durability of visceral and renal branches in patients undergoing endovascular repair of thoracoabdominal aortic aneurysms (TAAAs) with fenestrated/branched endovascular aneurysm repair (F/B-EVAR). METHODS: Quantitative branch vessel curvature assessment on branches arising from reinforced fenestrations was performed for 168 patients undergoing F/B-EVAR for type II and type III TAAAs. Preoperative and postoperative centerline coordinates were obtained using iNtuition (TeraRecon, Foster City, Calif) and exported into MATLAB (The MathWorks, Inc, Natick, Mass) based on thin-slice computed tomography imaging. Spline interpolation was applied to the centerline coordinates and resampled at 100 equally spaced points, and curvature calculations (κ, mm(-1)) were applied. Global and maximal curvatures for each of the target vessels were measured and categorized by severity. Categories for curvature were 0 to 0.05 mm(-1) (low), 0.05 to 0.1 mm(-1) (medium), 0.1 to 0.15 mm(-1) (high), and >0.15 mm(-1) (extreme) for global curvature and 0 to 0.2 mm(-1), 0.2 to 0.4 mm(-1), 0.4 to 0.6 mm(-1), and >0.6 mm(-1), respectively, for maximum curvature. Curvature variances were assessed for an association with vessel patency and need for reintervention. RESULTS: There were 558 vessels that underwent analysis based on repairs involving 650 vessels, whereby 92 vessels were excluded as they were treated with an external helical branch (58 celiac arteries and 34 superior mesenteric arteries). There was a significant difference found before and after F/B-EVAR for the global celiac artery curvature (median difference, -0.01; P < .001), global left renal artery curvature (median, -0.01; P = .014), maximum left renal artery curvature (median, 0.05; P < .001), and maximum right renal artery curvature (median, 0.03; P = .009). Maximum artery curvature was found to have shifted distally in all vessels postoperatively; 37 adverse events (AEs) were observed in 30 patients (6 branched occlusions and 31 reinterventions [24 type III endoleaks, 5 vessel stenoses, and 2 vessel occlusions]). The majority of AEs (>70%) occurred within the range of low to medium curvature. Univariate analysis found gender to be a dependent variable associated with high (maximum) preoperative curvature (odds ratio, 0.395; P = .02). The use of self-expanding stents (vs balloon-expandable stents alone) in vessels with high preoperative curvature (>0.6 mm(-1)) was significant in the right renal artery (P = .044). CONCLUSIONS: This study did not show a significant relationship between the severity of artery curvature or changes in curvature and AEs found for visceral or renal branches after F/B-EVAR for extensive TAAA. Surprisingly, the majority of AEs occurred in low- and medium-curved vessels. This study is limited in that it does not take into account other factors that may affect AEs, like motion, which would be valuable in future studies.