Initial Endovascular Aneurysm Repair Research Articles

Outcomes Following Different Management of Mycotic Infrarenal Abdominal Aortic Aneurysms.

The objective was to present our experience on managing mycotic infrarenal abdominal aortic aneurysm (MIAAA) through a retrospective cohort study. Data of patients with MIAAA managed in our center from July 2016 to October 2022 were retrospectively analyzed. The diagnosis of MIAAA was made based on: (1) preoperative clinical signs of infection; (2) elevated serologic infection parameters; (3) para-aneurysmal infection features on enhanced computed tomography; and (4) positive blood or tissue cultures. All the patients received standard antibiotic therapy. Surgical management including endovascular aneurysm repair (EVAR), initial EVAR followed by open re-operation, and initial open surgical repair (OSR) were conducted according to disease seriosity, physical condition, and patient's will. Infection index and clinical outcome were evaluated during the follow-up time. A total of 23 patients (21 men; averaged=66.3 years, range=49-79 years) were included, with a mean follow-up time of 19.9 months (range=1-75 months). Bacteria culture from blood or tissue specimen was positive in 15 patients (Salmonella, n=8; Escherichia coli, n=3; methicillin-sensitive Staphylococcus aureus [MSSA], n=1; Klebsiella pneumoniae, n=1; Staphylococcus epidermidis, n=1; Mycobacterium tuberculosis, n=1). Seven patients received OSR as the initial surgical intervention, whereas 14 patients chose EVAR instead. The 2 conservatively managed patients (refused surgery) died within 30 days. The 7 patients who received initial OSR survived till now. Among the 14 patients who underwent initial EVAR, infection deteriorated without exception (14/14, 100%). Three of these patients refused re-operation and died within 6 months. Eleven patients received secondary surgical intervention (10 cases of aneurysm and endograft resection, thorough debridement, subclavian to bi-femoral artery bypass, or in situ aorta reconstruction; 1 case of laparoscopic debridement) and 7 survived the follow-up time. The overall mortality rate was 39.1% (9/23). The mortality rates differed greatly following different intervention methods (merely antibiotic management, 100%; initial open operation, 0%; initial EVAR without secondary operation, 100%; initial EVAR plus secondary operation, 36.4%). Open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely EVAR is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary OSR. The management of mycotic or primary-infected aortic aneurysm is challenging; treatment remains controversial. Our center has reviewed our experience over the past 6 years and found that open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely endovascular aneurysm repair (EVAR) is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary open surgical repair.

Open Surgical Conversion After Endovascular Aortic Aneurysm Repair: A Systematic Review and Meta-Analysis.

Endovascular aneurysm repair (EVAR) is a preferred treatment for abdominal aortic aneurysms, though it comes with complications such as endoleaks and graft infections that may necessitate late open conversion (LOC). This systematic review and meta-analysis, drawing on studies from PubMed/MEDLINE, Embase, and the Cochrane Database of Systematic Reviews, aimed to evaluate the incidence, outcomes, and factors leading to LOC after EVAR. The analysis of 11 selected studies revealed a 5.3% incidence of LOC, with a patient cohort predominantly male (79%) and an average age of 73.5 years. The interval between initial EVAR and LOC was 35.1 months on average, with the Excluder device most frequently necessitating LOC. A notable 68% of endovascular salvage attempts before LOC failed. The study highlighted rupture and type I endoleak as the primary reasons for urgent LOC, which exhibited a 10-fold higher mortality rate compared to elective LOC. Elective LOC procedures had a 30-day mortality rate similar to primary elective open aneurysm repairs. These findings underscore the importance of vigilant post-EVAR patient monitoring and suggest that the methodological quality of underlying research should be considered in interpreting these results.

Late surgical conversion after failed endovascular aortic repair: Our single-institutional experience

Objectives: In this study, we report our single-center experience with late surgical conversion (SC) after endovascular aneurysm repair (EVAR) and risk factors for reintervention. Patients and methods: Between January 2007 and December 2017, a total of 98 patients (94 males, 4 females; mean age: 69.1±8.6 years; range, 35 to 86 years) who underwent infrarenal EVAR were retrospectively analyzed. During the study period, additional eight patients who underwent EVAR at an external center were referred to our center. Overall, nine patients underwent late SC. In the late SC group, stent grafts used for EVAR were Endurant™ (n=5), Talent™ (n=2), Powerlink™, and Anaconda™ (n=1). Results: The mean time from initial EVAR to open conversion was 45.3±35.4 months. Four (44.4%) patients presented with more than one different concomitant indications. The most frequent reason for the late SC was type 3 endoleak (n=5, 55.5%). Late SC was performed electively in five (55.5%) patients. Partial stent graft removal was performed in three (33.3%), complete removal in three (33.3%), and complete preservation of the stent graft in three (33.3%) patients. Among 98 patients, the mean aneurysm diameter was significantly higher in those with late complication and undergoing second EVAR (p=0.001). The cut-off value for second EVAR was ≥66 mm with a sensitivity of 88.89% and specificity of 71.91% (p=0.001). Conclusion: The surveillance program after EVAR is of utmost importance to ensure that patients do not need urgent conversion, particularly in patients with an initial aneurysm diameter of ≥66 mm.

Multicenter Comparative Analysis of Late Open Conversion in Patients With Adherence and Nonadherence to Instructions for Use Endovascular Aneurysm Repair

Purpose: The widespread adoption of endovascular aneurysm repair (EVAR) as preferred treatment modality for abdominal aortic aneurysm (AAA) has enlarged the number of patients needing open surgical conversion (OSC). The relationship between adherence to Instructions For Use (IFU) and EVAR long-term outcomes remains controversial. The aim of this study is to compare preoperative differences and postoperative outcomes between EVAR patients not adjusted to IFU and adjusted to IFU who underwent OSC. Methods: This multicenter retrospective study reviewed 33 explanted EVARs between January 2003 and December 2019 at 14 Vascular Units. Patients were included if OSC occurred >30 days after implantation and excluded if explantation was performed to treat an endograft infection, aortic dissection, or traumatic transections. Variables analyzed included baseline characteristics, adherence to IFU, implant and explant procedural details, secondary reinterventions, and postoperative outcomes. Results: Fifteen explanted patients (15/33, 45.5%) were identified not accomplished to IFU (out-IFU) at initial EVAR vs 18 explanted patients adjusted (in-IFU). During follow-up, a mean of 1.73±1.2 secondary reinterventions were performed, with more type I endoleaks treated in the subgroup out-IFU: 16.7% vs 6.3% in-IFU patients and more type III endoleaks (8.3% vs 0%). Patients out-IFU had shorter mean interval from implant to explant: 47.60±28.8 months vs 71.17±48. Type II endoleak was the most frequent indication for explantation. Low-flow endoleaks (types II, IV, V) account for 44% of indications for OSC in subgroup of patients in-IFU, compared with 13.3% in patients out-IFU and high-flow endoleaks (types I and III) were the main indication for patients out-IFU (33.3% vs 16.7% in-IFU). Total endograft explantation was performed in 57.5% of cases (19/33) and more suprarenal clamping was required in the subgroup out-IFU. Overall, 30-day mortality rate was 12.1% (4/33): 20% for patients out-IFU and 5.6% in-IFU. Conclusions: In our experience, type II endoleak is the most common indication for conversion and differences have been found between patients treated outside IFU with explantation taking place earlier during follow-up, mainly due to high-flow endoleaks and with higher mortality in comparison with patients adjusted to IFU. Ongoing research is required to delve into these differences.

Incidence and Fate of Refractory Type II Endoleak after EVAR: A Retrospective Experience of Two High-Volume Italian Centers.

Introduction: The aim of the present study is to report the outcome of patients presenting an isolated type II endoleak (TIIEL) requiring reintervention and to identify clinical and anatomical characteristics potentially implicated in refractory TIIEL occurrence and fate. Materials and Methods: A multicenter retrospective study on TIIEL requiring reintervention was conducted between January 2003 and December 2020. Demographic and clinical characteristics, procedural technical aspects, reinterventions, and outcomes were recorded. TIIEL determining sac expansion greater than 10 mm underwent a further endovascular procedure aiming to exclude aneurismal sac. Redo endovascular procedures were performed via endoleak nidus direct embolization and/or aortic side branches occlusion. TIIELs responsible for persisting aneurysmal sac perfusion 6 months after redo endovascular procedures were classified as “refractory” and submitted to open conversion. Results: A total of 102 TIIEL requiring reintervention were included in the final analysis. Eighty-eight (86.27%) patients were male, the mean age was 77.32 ± 8.08 years, and in 72.55% of cases the American Society of Anaesthesiologists (ASA) class was ≥3. The mean aortic diameter was 64.7 ± 14.02 mm, half of treated patients had a patent inferior mesenteric artery (IMA), and 44.11% ≥ 3 couples of patent lumbar arteries (LA). In 49 cases (48.03%) standard endovascular aneurysm repair (EVAR) procedure was completed without adjunctive maneuvers. All enrolled patients were initially submitted to a further endovascular procedure once TIIEL requiring reintervention was diagnosed; 57 patients underwent LAs or IMA embolization (55.87%), 42 transarterial aneurismal sac embolization (41.17%), and three (2.96%) laparoscopic ostial ligations of the inferior mesenteric artery. During a mean follow-up of 15.22 ± 7.57 months (7–48), a redo endovascular approach was able to ensure complete sac exclusion in 52 cases, while 50 patients presented a still evident refractory TIIEL and therefore a surgical conversion or semiconversion was conducted. At the univariate analysis refractory TIIEL patients were significantly different from those who did not develop the complication in terms of preoperative clinical, morphological characteristics, and initial EVAR procedures: coronary artery disease occurrence (p = 0.005, OR: 3.18, CI95%: 1.3–7.2); preoperative abdominal aortic aneurysm (AAA) sac diameter (p = 0.0055); IMA patency (p = 0.016, OR: 2.64, CI95%: 1.18–5.90); three or more patent LAs; isolated standard EVAR without adjunctive procedures (p > 0.0001; OR: 9.48, CI95%: 3.84–23.4). Conclusions: Our experience seems to demonstrate that it is reasonable to try to preoperatively identify those patients who will develop a refractory TIIEL after EVAR and those with a TIIEL requiring reintervention for whom a simple endovascular redo will not be enough, needing surgical conversion.

Outcomes of Late Open Conversion after Endovascular Abdominal Aneurysm Repair.

Objective: To review our experience with a late open conversion as a final option for an endograft infection and aneurysm expansion after endovascular aneurysm repair (EVAR), especially in endoleaks for which radiological intervention is impossible.Materials and Methods: In this retrospective study, 13 late open conversions out of 513 consecutive patients treated by EVAR were analyzed. Indications for an open conversion were aneurysm enlargement, including all endoleaks, endograft migration, and endograft infection. The patients’ data on demographics, operative details, and outcomes were reviewed.Results: Indications for a late open conversion included endoleaks, infection, and migration in 61.5%, 30.8%, and 7.7% of patients, respectively. The median interval from the initial EVAR was 32.4 months. Complete endograft explantation was performed in four patients with an endograft infection. In endoleak cases, the endograft was partially preserved and a neo-neck was used. Sacotomy and branch ligation were performed in one case. One major operative complication was an aortic injury during infrarenal aortic cross-clamping in an endograft migration case. There was no operative mortality.Conclusion: A late open conversion after EVAR is valuable as a final option. The aortic cross-clamp site, especially in endograft migration cases, should be carefully considered. To avoid aneurysm-related events, graft replacement is recommended, if possible.

PC032. Long-term Outcomes and Interventions of Postoperative Type IA Endoleaks After Elective Endovascular Aneurysm Repair

This study evaluated the incidence and long-term outcomes of postoperative type IA endoleak (PT1A) after endovascular aneurysm repair (EVAR). Following Institutional Review Board approval, a retrospective review of consecutive aortoiliac EVARs performed at a single institution between June 2006 and June 2012 was conducted. Patients with an indication of nonruptured infrarenal abdominal aortic aneurysm were included, and those without follow-up were excluded from the study. Patients' demographics, comorbidities, preoperative evaluation, intraoperative details, and postoperative complications were collected. PT1A was identified by postoperative imaging follow-up. PT1A patients were compared with those who had persistent intraoperative type IA endoleak (IT1A) on completion angiography during initial EVAR that had resolved on initial follow-up imaging. There were 627 patients who underwent EVAR at our institution during the designated period, with a final cohort of 389 patients after inclusion and exclusion criteria were applied. Average length of follow-up was 68.8 months (0-194 months). The incidence of PT1A was 8.2 % (n = 32). Compared with the total cohort, those who developed PT1A were statistically more likely to be male (P = .03) and to have a higher all-cause mortality (P < .001) and aorta-related mortality (P = .03). Mean time to presentation was 52.3 months. Of the 32 PT1A patients, 5 (15.6%) presented with aortic rupture, of whom 3 underwent extension cuff placement, 1 had open graft explantation, and 1 declined intervention. Six patients in total (18.7%) declined intervention. Within the 26 PT1A patients who had intervention, 21 (80.7%) showed resolution of PT1A and 5 (19.2%) had recurrence. For patients with recurrent PT1A, three refused further intervention and two had extension cuff placement. Patients with PT1A who had intervention with resolution had significantly increased all-cause mortality compared with the total EVAR cohort (P = .02). Within the PT1A cohort, six (18.7%) had IT1A on completion angiography, with a mean time to presentation of 39 months. Four underwent intervention, all with resolution of the type IA endoleak. IT1A was associated with a significantly decreased median survival (P = .003), but there was no aorta-related mortality. The development of PT1A after elective EVAR is associated with increased aorta-related mortality and presented an average of 52 months postoperatively within our cohort. This underscores the importance of long-term follow-up surveillance. Patients with PT1A who had a successful intervention still demonstrated an increase in all-cause mortality. The incidence of IT1A may decrease median survival but was not associated with aorta-related mortality.

Risk factors and treatment outcomes for stent graft infection after endovascular aortic aneurysm repair

ObjectiveWe aimed to retrospectively analyze incidence, risk factors, and management of postoperative stent graft (SG) infection after endovascular aneurysm repair (EVAR). MethodsWe evaluated patients who underwent EVAR for infrarenal abdominal aortic aneurysm at our institution between July 2006 and December 2014. The primary end point was SG infection. We compared patients' demographics between the infection (group I) and noninfection (group NI) groups and reviewed management and outcomes in group I. A risk factor for SG infection was assessed by multivariable logistic regression. Patients without aortoenteric fistula (AEF) were treated with conservative therapy for SG infection. ResultsA total of 1202 patients underwent EVAR for infrarenal abdominal aortic aneurysm. During a mean follow-up of 43.9 ± 30.4 months, SG infection occurred in 15 cases (incidence, 3.5/1000 person-years). The median time between initial EVAR and detection of infection was 30 months (range, 14 days-86 months). Freedom from SG infection at 1 year, 3 years, and 5 years was 99.5%, 99.2%, and 98.2%, respectively. There were no differences in age, sex, comorbidities, and SG type between the groups. Coil embolization of the hypogastric artery was more frequent in group I (60% vs 31%). During follow-up before infection, type II endoleak (47% vs 24%), sac enlargement (40% vs 16%), and multiple reinterventions (13% vs 2%) were significantly higher in group I; however, after multivariate analysis, only coil embolization of the hypogastric artery (odds ratio, 3.22; 95% confidence interval, 1.12-9.24; P = .029) remained a significant predictor. Among the 15 patients, four had AEF and six bacteriologic species were detected in five patients (33%). Twelve patients (80%) were treated with conservative therapy; three underwent surgical therapy (two patients with SG resection, omentum patching, and extra-anatomic bypass with fistula closure or partial duodenectomy and one patient with graft preservation, irrigation, omentum patching, and aneurysmorrhaphy). In-hospital mortality occurred in three cases; two cases were due to sepsis after conservative therapy, and one case was due to aortic stump rupture after surgical therapy. Excluding in-hospital mortality cases, during a median follow-up of 31 (range, 2-76) months, five patients were lost because of cancer or senility. There was no aneurysm-related death or recurrence of SG infection. ConclusionsConcomitant coil embolization was a risk factor for SG infection. For patients with AEF, surgical therapy remains the first-line treatment of SG infection after EVAR; however, conservative therapy is a viable option for SG infection in patients without AEF, particularly considering patients' comorbidities and limited life expectancy.

Editor's Choice – Late Open Surgical Conversion after Endovascular Abdominal Aortic Aneurysm Repair

Late open surgical conversion following endovascular aneurysm repair (EVAR) may occur more frequently after performing EVAR in anatomy outside the instructions for use (IFU). This study reviews predictors and outcomes of late open surgical conversion for failed EVAR. This retrospective cohort study reviewed all EVARs performed at the Ottawa Hospital between January 1999 and May 2015. Open surgical conversions >1 month post EVAR were identified. Variables analysed included indication for conversion, pre-intervention AAA anatomy, endovascular device and configuration, operative technique, re-interventions, complications, and death. Of 1060 consecutive EVARs performed, 16 required late open surgical conversion. Endografts implanted were Medtronic Talent (n = 8, 50.0%), Medtronic Endurant (n = 3, 18.8%), Cook Zenith (n = 4, 25.0%), and Terumo Anaconda (n = 1, 6.2%). Eleven grafts were bifurcated (68.8%), five were aorto-uni-iliac (31.2%). The median time to open surgical conversion was 3.1 (IQR 1.0-5.2) years. There was no significant difference in pre-EVAR rupture status (1.4% elective, 2.1% ruptured, p=.54). Indications for conversion included: Type 1 endoleak with sac expansion (n=4, 25.0%), Type 2 endoleak with expansion (n=2, 12.5%), migration (n=3, 18.8%), sac expansion without endoleak (n=2, 12.5%), graft infection (n=3, 18.8%), rupture (n=2, 12.5%). Nine patients (56.2%) underwent stent graft explantation with in situ surgical graft reconstruction, seven had endograft preserving open surgical intervention. The 30 day mortality was 18.8% (n=3, all of whom having had endograft preservation). Ten patients (62.5%) suffered major in hospital complications. One patient (6.5%) required post-conversion major surgical re-intervention. IFU adherence during initial EVAR was 43.8%, versus 79.0% (p<.01) among uncomplicated EVARs. Open surgical conversion following EVAR results in significant morbidity and mortality. IFU adherence of EVARs later requiring open surgical conversion is markedly low. More data are required to elucidate the impact of increasing liberalisation of EVAR outside of IFU.

Management of Difficult Access during Endovascular Aneurysm Repair

To describe a large single-institutional experience in managing challenging access situations during endovascular aneurysm repair (EVAR). Data from all patients undergoing EVAR at a tertiary academic medical center between 2009 and 2013 were collected retrospectively, including demographics, size of iliac arteries, type of device used, approach to managing difficult access (DA), and outcomes. The median follow-up was 38months. DA was defined as iliac arteries with a diameter of less than 7mm bilaterally. Fenestrated and snorkel repairs were excluded. Of 400 EVARs performed during the study period, 191 (48%) were done in patients with DA. Of the DA patients, 35 (18.3%) underwent 42 adjuncts before the introduction of the main body device: including 15 dilators, 11 balloon angioplasties, 9 aortouniiliac devices, 3 SoloPath sheaths, 1 retroperitoneal cutdown, and 3 iliac stents. In another 29 patients, iliac stents were used to correct stenoses or kinks in the limbs after EVAR devices were deployed. The average diameter of the iliac artery used to deliver main body component was 4.6mm in the group of patients requiring adjuncts and 5.4mm in the remainder of the patients with small iliac arteries (P=0.008). The median size of the main body device was 28mm. Two cases were aborted due to inability to deliver the device. Other complications included 7 (3.6%) iliac ruptures, 3 (1.6%) instances of limb ischemia, and 5 (2.6%) patients needed early reoperation (within 30days). Two patients (1%) had type I endoleaks at the conclusion of EVAR. During follow-up, 12 (6.3%) patients required EVAR revisions. Seven patients (3.6%) had limb thrombosis which occurred only in patients who did not have adjective procedures during the initial EVAR. Limb thrombosis and rate of revisions in patients with DA were not significantly different from the rates observed in non-DA patients. Perioperative mortality after elective repairs was 1.6% in DA patients and 0% in non-DA patients (P=0.12). EVAR can be successfully performed in patients with bilateral small iliac arteries. Adjunctive procedures might increase the technical success rate of EVAR in these patients and should definitely be considered in patients with iliac arteries less than 5mm in diameter. Next generation and "low-profile" devices might minimize the need for adjunctive procedures and facilitate EVAR in these patients.

Incidence, etiology, and management of type III endoleak after endovascular aortic repair

ObjectiveThe objective of this study was to retrospectively assess the incidence, etiology, and management of type III endoleaks in a large cohort of patients treated with endovascular aneurysm repair (EVAR) in two European university centers. MethodsFrom 1995 until 2014, 965 EVAR procedures were performed with use of first- and second-generation (n = 79) or third-generation (n = 886) endografts. Radiologic follow-up was performed with computed tomography and abdominal plain film examinations in accordance with the European Collaborators on Stent/graft Techniques for aortic Aneurysm Repair (EUROSTAR) scheme. The potential relationship between the type of endograft and the incidence of type III endoleak and the time interval between initial EVAR and diagnosis of type III endoleak were calculated. ResultsTwenty patients (2.1%) were identified with 25 type III endoleaks (n = 10/79 [12.7%] for first- and second-generation endografts and n = 10/886 [1.2%] for third-generation endografts; P < .001). Disconnection was found in 14 of 25 endoleaks (56%) and a fabric defect in 11 of 25 (44%) endoleaks, both without any difference between first- and second- vs third-generation endografts (P = .216). The time interval between initial EVAR and type III endoleak was 3.87 and 5.92 years, respectively, for first- or second-generation and third-generation endografts (P = .148). Twenty-five type III endoleaks were treated using endovascular techniques (n = 22 [88%]) or by open surgical conversion (n = 3 [12%]). ConclusionsType III endoleak rarely (2.1%) occurs after EVAR, with a higher incidence in first- and second-generation endografts. In the majority of cases, the underlying mechanism is disconnection of the stent graft components. Type III endoleaks may occur early or late after initial EVAR and can, in most cases, be managed endovascularly, although type III endoleak may recur.

Aortic Curvature Is a Predictor of Late Type Ia Endoleak and Migration After Endovascular Aneurysm Repair

Purpose: To evaluate the association between aortic curvature and other preoperative anatomical characteristics and late (>1 year) type Ia endoleak and endograft migration in endovascular aneurysm repair (EVAR) patients. Methods: Eight high-volume EVAR centers contributed 116 EVAR patients (mean age 81±7 years; 103 men) to the study: 36 patients (mean age 82±7 years; 31 men) with endograft migration and/or type Ia endoleak diagnosed >1 year after the initial EVAR and 80 controls without early or late complications. Aortic curvature was calculated from the preoperative computed tomography scan as the maximum and average curvature over 5 predefined aortic segments: the entire infrarenal aortic neck, aneurysm sac, and the suprarenal, juxtarenal, and infrarenal aorta. Other morphological characteristics included neck length, neck diameter, mural neck calcification and thrombus, suprarenal and infrarenal angulation, and largest aneurysm sac diameter. Independent risk factors were identified using backward stepwise logistic regression. Relevant cutoff values for each of the variables in the final regression model were determined with the receiver operator characteristic curve. Results: Logistic regression identified maximum curvature over the length of the aneurysm sac (>47 m−1; p=0.023), largest aneurysm sac diameter (>56 mm; p=0.028), and mural neck thrombus (>11° circumference; p<0.001) as independent predictors of late migration and type Ia endoleak. Conclusion: Aortic curvature is a predictor for late type Ia endoleak and endograft migration after EVAR. These findings suggest that aortic curvature is a better parameter than angulation to predict post-EVAR failure and should be included as a hostile neck parameter.

Predictors of early aortic neck dilatation after endovascular aneurysm repair with EndoAnchors

ObjectiveDilatation of the aorta within the proximal neck after endovascular aneurysm repair (EVAR) can be associated with late endoleaks and migration. This study was designed to identify predictors of early neck dilation in patients undergoing EVAR with Heli-FX EndoAnchors (Medtronic, Santa Rosa, Calif) measured perioperatively to 1 year at different longitudinal levels of neck length. MethodsThe study group of Aneurysm Treatment Using the Heli-FX Aortic Securement System (ANCHOR) comprises 257 consecutive patients prospectively enrolled between April 2012 and September 2014 undergoing EVAR with Heli-FX EndoAnchor implantation at 38 investigational sites. Only patients undergoing EndoAnchor implantation at the time of the initial EVAR were included (primary treatment arm). Aortic diameter was measured at the suprarenal level and at three levels within the proximal neck. Neck dilatation was assessed in 209 patients with adequate computed tomography imaging at baseline and 1 month and in 62 patients at 1 month and 1 year (mean, 11.9 ± 4.0 months). Multivariable analyses were performed to identify independent predictors of perioperative (baseline to 1 month) and early postoperative (1 month to 1 year) aortic dilation at each level; analyses included 6 candidate variables, 6 clinical, and 14 anatomic run in eight models (one at each of the four aortic levels for both time frames). ResultsThe mean aortic neck dilation at 1 month was 0.2 ± 1.7 mm, 0.7 ± 2.2 mm, and 0.9 ± 3.6 mm at 0 mm, 5 mm, and 10 mm below the lowest renal artery, and 0.0 ± 1.5 mm at the suprarenal level. From 1 month to 1 year, neck dilatation was 0.5 ± 1.6 mm, 0.4 ± 1.5 mm, 0.2 ± 1.8 mm, and −0.3 ± 1.1 mm at the same four levels, respectively. Dilatation of ≥3 mm at level 5 mm distal to the lowest renal artery was observed in 26 patients (12.5%) from preoperative to 1 month and in 5 patients (8.1%) between 1 month and 1 year. Multivariable regression identified several variables predictive of perioperative (preoperative to 1 month) neck dilatation: baseline neck diameter, mural calcium (protective), and endografts with a suprarenal stent. Neck dilatation between 1 month and 1 year was associated with baseline neck diameter, neck length (protective), neck angulation, device oversizing, number of EndoAnchors implanted (protective), and endografts with a suprarenal stent. ConclusionsAortic diameter and graft oversizing appear to be independent risk factors for early aortic neck dilatation. EndoAnchors have a protective effect on neck dilatation at their usual level of deployment.

Late Open Surgical Conversion After Endovascular Abdominal Aortic Aneurysm Repair: A Review of 15 Years of Experience

Late open conversion following endovascular aneurysm repair (EVAR) represents a failure of therapy, used to treat complications refractory to secondary endovascular intervention. With liberalization of EVAR and expansion to populations outside of instructions for use (IFU), it is imperative to better understand predictors and to prevent this outcome. The objective of this study was to understand the patterns of presentation, graft-specific differences, outcomes of interventions, and relationship to IFU adherence among patients who underwent late open conversion of EVAR. Records of 1038 consecutive patients who underwent EVAR at The Ottawa Hospital between October 2000 and May 2015 were reviewed from a prospective database. Patients requiring conversion to open repair >1 month after implantation were identified. Patients who underwent fenestrated, branched, or thoracic endovascular repair were excluded. Variables analyzed included date of interventions, adherence to IFU, graft type, interval to open conversion surgery, reason for removal, operative technique, length of stay, hospital complications, and death. A total of 16 patients underwent EVAR that required subsequent late conversion to open repair. Initial grafts implanted included Medtronic (Santa Rosa, Calif) Talent (eight patients, 50.0%), Medtronic Endurant (three patients, 18.8%), Cook (Bloomington, Ind) Zenith (four patients, 25.0%), and Terumo (Somerset, NJ) Anaconda (one patient, 6.2%). Average time to intervention was 3.3 ± 2.5 years, and this interval decreased during the study period (4.6 ± 3.0 years for EVARs before 2007 vs 2.89 ± 1.37 years for EVARs after 2009). Indications for conversion were graft infection in four patients (25%), aneurysm rupture in two patients (12.5%), endograft migration in three patients (18.8%), sac expansion secondary to type Ia endoleak in three patients (18.8%), sac expansion secondary to type II endoleak in two patients (12.5%), and sac expansion without detectable endoleak in two patients (12.5%). Nine patients (56.2%) underwent open conversion by stent graft explantation with in situ graft reconstruction; the remaining seven patients were treated with open cerclage of the aneurysm sac around the device. The 30-day mortality was 18.8%. Major in-hospital complications occurred in 10 patients (62.5%). An additional two patients (12.5%) required postconversion surgical reintervention. During initial EVAR, operators were adherent to device IFU in seven cases (43.8%), which is markedly lower than IFU adherence rates of 88.0% among uncomplicated EVARs in our database. Conversion to open repair following EVAR is associated with significant morbidity and mortality. The rate of operator adherence to IFU at time of initial EVAR in this cohort of open conversions is markedly low in comparison to the overall EVAR cohort. The decreasing interval to open conversion is concerning and may be a reflection of increasing liberalization of EVAR to populations outside of IFU.

Treatment of Type IIIb Endoleaks After EVAR Using the Nellix EndoVascular Aneurysm Sealing System

Purpose: To describe the successful endovascular treatment of 2 patients with type IIIb endoleak using the Nellix EndoVascular Aneurysm Sealing (EVAS) System. Case Report: Two men aged 75 and 83 years presented with type IIIb endoleak several years (8 and 3, respectively) after initial endovascular aneurysm repair. Dual Nellix endoprosthesis were deployed in the stent-grafts, and the endobags were filled with polymer to seal the defect and eliminate the endoleak. The perioperative periods were uneventful. At up to 6-month follow-up, no endoleaks were detected, aneurysm diameters were unchanged, and the endografts were patent. One patient died 7 months after revision due to a metastatic malignancy. Conclusion: The Nellix EVAS System may prove useful for the treatment of type IIIb endoleak.

Late Rupture of Abdominal Aortic Aneurysm After Previous Endovascular Repair

Purpose: To report a systematic literature review of late rupture of abdominal aortic aneurysm (AAA) after endovascular aneurysm repair (EVAR) and the results of a pooled analysis of causes, treatment, and outcomes. Methods: Electronic information sources and bibliographic reference lists were interrogated using a combination of free text and controlled vocabulary searches; 11 articles were ultimately identified that fulfilled the inclusion criteria. The articles reported a total of 190 patients who were included in the qualitative and quantitative synthesis. Mortality within 30 days or during the admission with aneurysm rupture was a primary endpoint; major perioperative morbidity was a secondary endpoint. A meta-analysis was performed for 30-day/in-hospital mortality using the random effects model. Results: A total of 152 ruptures occurred after 16,974 EVAR procedures reported by 8 of the case series, giving an incidence of 0.9% [95% confidence interval (CI) 0.77 to 1.05]. The mean time to rupture was 37 months. Twenty-nine percent (95% CI 20 to 39) of the patients had at least one previous secondary endovascular intervention following the initial EVAR, and 37% (95% CI 30 to 45) were not compliant with surveillance. Type I and III endoleaks were the predominant causes of rupture. Open surgical treatment was undertaken in 61% (95% CI 53 to 68) of the patients who underwent treatment. The pooled estimate for perioperative mortality was 32% (95% CI 24 to 41). A significantly lower mortality was found with endovascular treatment than open surgical management (p=0.027). Conclusion: Graft-related endoleaks appear to be the predominant causes of late aneurysm rupture. Quality of and compliance with post-EVAR surveillance are important factors in late rupture; a large proportion of late ruptures are amenable to endovascular treatment.

Results of transcaval embolization for sac expansion from type II endoleaks after endovascular aneurysm repair

Management of type II endoleaks after endovascular aneurysm repair can be problematic. This study reports our experience with a relatively novel strategy to treat this complication, transcaval coil embolization (TCCE) of the aneurysm sac. We reviewed 29 consecutive patients undergoing TCCE from 2010 to 2013. Demographics, operative details, and outcomes were assessed. Since 2006, 29 TCCEs have been performed at our institution in 26 patients for sac expansion from type II endoleaks. Patients were male (83%) and former or current smokers (88%), with an average age of 78 ± 7.1 years. TCCE was performed a mean of 4.2 ± 4 years after initial endovascular aneurysm repair. Endoleaks resulted in a mean sac growth of 1.2 ± 1 cm in diameter and 37% ± 32% by volume. Forty-six percent had prior procedures (5 translumbar, 3 transarterial, 3 transcaval, 1 aortic cuff, and 1 iliac limb extension). Two patients had no flow identified in the aneurysm sac after puncture was successful, and one was found to have a hygroma rather than arterial flow. An additional two patients had ultimate embolization from sac access between the endograft iliac limb and arterial wall after transcaval puncture failed, for a 90% procedural success (83% for transcaval technical success). Mean fluoroscopy time was 27 ± 13 minutes with 29 ± 21 mL of contrast material used and a median of 10 coils per case. Additional adjuncts included thrombin injection (17%), intravascular ultrasound (14%), sac pressure measurements (28%), and on-table integrated computed tomography (17%). Median length of stay was 1 day (range, 0-5 days). There were no procedural adverse events. Reintervention was required in five cases (three repeated TCCEs, two graft relinings). One-year freedom from reintervention was 95%. At a mean 16.5 months of follow-up, 70% experienced no further endoleak and had stable or decreasing sac diameters. There have been no ruptures during follow-up. In this series, TCCE for treatment of aneurysm enlargement due to type II endoleaks was safe and relatively effective despite prior failed interventions in nearly half of the cases. TCCE is a useful alternative in cases in which the anatomy makes other approaches difficult or impossible.

Analysis of EndoAnchors for endovascular aneurysm repair by indications for use

The proximal aortic neck remains one of the challenges of endovascular aneurysm repair (EVAR), and the risk of type Ia endoleak and endograft migration is increased in patients with short, large-diameter, or highly angulated necks. EndoAnchors have been used as an adjunct to EVAR in such patients, and the aim of this study was to assess their benefit analyzed by indication for use. During a 2-year period, 319 patients were enrolled at 43 sites in the Aneurysm Treatment Using the Heli-FX Aortic Securement System Global Registry (ANCHOR) study. This prospective, multinational, real-world analysis of EndoAnchors comprised two groups of patients, those undergoing first-time EVAR (primary arm, 242) and those with proximal neck complications remote from the time of an initial endograft implantation (revision arm, 77). The primary arm was further subdivided into patients undergoing prophylactic EndoAnchor use for hostile proximal neck anatomy (178), with a type Ia endoleak evident during initial endograft deployment (60), and in conjunction with extender cuffs after unsatisfactory endograft deployment distally in the neck (four). The revision arm was subdivided into patients presenting with a type Ia endoleak alone (45), endograft migration alone (11), and migration with endoleak (21). Technical success was site reported as satisfactory deployment of the desired number of EndoAnchors without fracture or loss of integrity. Procedural success was defined as technical success without type Ia endoleak at completion arteriography. Core laboratory analysis was performed on 249 baseline and 192 follow-up computed tomographic studies, 66 of which were available within the 1-year window. Technical and procedural success rates were highest in the prophylactically treated subset (172 of 178; 96.6%). Whereas the technical success of EndoAnchor deployment was also high in the other subsets, residual type Ia endoleaks were more frequent at completion angiography when the indication for EndoAnchor use was type Ia endoleak, both in the primary arm (17 of 60; 28%) and in the revision arm (9 of 45; 20%). During a median imaging follow-up of 7 months, 183 of 202 patients (90.1%) remained free of type Ia endoleaks. Primary prophylactic patients were free from type Ia endoleak in 110 of 114 cases (96.5%). The most challenging subset was revision patients treated for type Ia endoleak; type Ia endoleaks were evident during follow-up in 10 of 29 of the cases (34%). Sac regression >5 mm in patients with 1-year imaging was observed in 26 of 66 patients (39%) and was highest in the primary prophylaxis subset (20 of 43; 47%). EndoAnchor implantation can be a useful adjunct to EVAR as prophylaxis against proximal attachment site complications in patients with hostile aortic neck anatomy, as treatment for early and late type Ia endoleaks, or, in conjunction with aortic extension cuffs, for endograft migration. Whereas the most challenging patients are those who present with type Ia endoleaks remote from initial EVAR, EndoAnchors are still effective in treating the majority of these cases.

Late rescue of proximal endograft failure using fenestrated and branched devices

Endovascular aneurysm repair (EVAR) will fail over time in a percentage of patients. Mechanical failure of the device, progression of aortic disease, or interface complications between the device and the native vasculature may contribute. Our aim was to evaluate the role of fenestrated and branched endografts as treatment options for failed devices. Between January 2001 and June 2013, 970 patients were enrolled into a physician-sponsored investigational device exemption (PSIDE) study and treated with a fenestrated/branched endograft. All patients treated for nonurgent proximal neck failure of an infrarenal endoprosthesis previously implanted during EVAR comprised the study group. Patients treated for a primary aneurysm within the PSIDE were evaluated as a comparison group to identify preoperative risk factors for failure. A retrospective review was undertaken to determine the details of the initial EVAR, whereas the prospective PSIDE database was used to assess outcomes of secondary treatment. Three-dimensional imaging techniques were used to define all morphologic measurements. Statistical analysis included comparisons between categoric variables with the χ(2) test and between continuous variables with the Wilcoxon rank sum test between patients with late failures and those with native aortic repair. Kaplan-Meier curves were used to analyze overall survival. Of 970 patients enrolled in the PSIDE, 54 (5.6%) had late failure of a prior endograft. Fenestrated/branched devices were used to address the failure in each patient. The etiology of failure was related to a proximal neck issue in all patients: type Ia endoleak in 38, stent migration in 18, neck degeneration in 28, or some combination of these factors. The endovascular rescue procedure took place a mean of 61 months after the primary procedure. The mean aneurysm diameter at reintervention was 67 mm. Patients requiring a secondary fenestrated procedure were younger at the time of their primary intervention (P = .039) and were more likely to have a history of chronic renal insufficiency (P = .05) compared with other patients in the PSIDE. Technical success rate in the study group was 85% (44 of 52). Successful stenting was achieved in 71 of 77 (92%) target vessels. Thirty-day mortality was 3.8% (two of 52). Fluoroscopy dose and operating time were longer in the rescue group (P = .07) than in the control group (P = .008). Secondary interventions were required in 36.5% (19 of 52) of patients. Our series demonstrates the risk for late failure after EVAR is greater in patients who are younger and have chronic renal impairment at the time of implantation. Branched and fenestrated repair after failed EVAR is more complex than repair in the native aorta. More research is needed to identify patients at higher risk of failure after EVAR to prevent the need for rescue in the future.

Late graft explants in endovascular aneurysm repair

With more than a decade of use of endovascular aneurysm repair (EVAR), we expect to see a rise in the number of failing endografts. We review a single-center experience with EVAR explants to identify patterns of presentation and understand operative outcomes that may alter clinical management. A retrospective analysis of EVARs requiring late explants, >1 month after implant, was performed. Patient demographics, type of graft, duration of implant, reason for removal, operative technique, length of stay, complications, and in-hospital and late mortality were reviewed. During 1999 to 2012, 100 patients (91% men) required EVAR explant, of which 61 were placed at another institution. The average age was 75 years (range, 50-93 years). The median length of time since implantation was 41 months (range, 1-144 months). Explanted grafts included 25 AneuRx (Medtronic, Minneapolis, Minn), 25 Excluder (W. L. Gore & Associates, Flagstaff, Ariz), 17 Zenith (Cook Medical, Bloomington, Ind), 15 Talent (Medtronic), 10 Ancure (Guidant, Indianapolis, Ind), 4 Powerlink (Endologix, Irvine, Calif), 1 Endurant (Medtronic), 1 Quantum LP (Cordis, Miami Lakes, Fla), 1 Aorta Uni Iliac Rupture Graft (Cook Medical, Bloomington, Ind), and 1 homemade tube graft. Overall 30-day mortality was 17%, with an elective case mortality of 9.9%, nonelective case mortality of 37%, and 56% mortality for ruptures. Endoleak was the most common indication for explant, with one or more endoleaks present in 82% (type I, 40%; II, 30%; III, 22%; endotension, 6%; multiple, 16%). Other reasons for explant included infection (13%), acute thrombosis (4%), and claudication (1%). In the first 12 months, 23 patients required explants, with type I endoleak (48%) and infection (35%) the most frequent indication. Conversely, 22 patients required explants after 5 years, with type I (36%) and type III (32%) endoleak responsible for most indications. The rate of EVAR late explants has increased during the past decade at our institution. Survival is higher when the explant is done electively compared with emergent repair. Difficulty in obtaining a seal at the initial EVAR often leads to failure ≤1 year, whereas progression of aneurysmal disease is the primary reason for failure >5 years.