Secondary Intervention After Endovascular Abdominal Aortic Aneurysm Repair

Outcomes Associated with Type 2 Endoleaks After Infrarenal Endovascular Aneurysm Repair in the Vascular Quality Initiative Linked to Medicare Claims

OBJECTIVE

Type 2 endoleaks (T2EL) are commonly identified after endovascular aneurysm repair (EVAR) and may occur either at the completion of the procedure or during follow-up. However, the impact of T2EL on reintervention and survival remains poorly described. This study aims to evaluate the outcomes associated with T2EL in a real-world cohort using the Vascular Quality Initiative linked Medicare claims (VQI-Medicare) database.

METHODS

We retrospectively reviewed all elective EVARs in the VQI-Medicare (part of the Vascular Implant Surveillance and Interventional Outcomes [VISION] coordinated registry network) database from 2010-2018. Patients with Medicare fee-for-service entitlement at the time of the index procedure and continuous entitlement during follow-up were included. We excluded patients with endoleaks other than T2EL at completion or follow-up, those with missing T2EL status at completion, and subjects with no imaging follow-up. The primary outcomes were aneurysm-related reintervention, freedom from rupture, and overall survival. A time-dependent analysis based on the T2EL status, and Cox proportional hazards multivariable models were used to assess associations between T2EL and the outcomes.

RESULTS

A total of 8,195 patients were included in the final analysis, with 6,653 (81%) in the NO T2EL group and 1,542 (19%) in the T2EL group. Patients in the T2EL group were older (76 vs. 75 years, p=.006) and had lower rates of active smoking (21% vs. 26%, p<.001), COPD (28% vs. 32%, p=.003), congestive heart failure (9% vs. 12%, p=.004) and history of prior vascular intervention. At 5 years, the rate of aneurysm-related reintervention was significantly higher in the T2EL group (30.4% vs. 11%, p<.0001); however, there was no significant difference in freedom from rupture between the groups (95.6% vs. 98.2%, aHR 0.98, 95%CI 0.5-2). Unadjusted overall survival at 5 years was similar between the groups (74% vs. 71%). On multivariate regression analysis, presence of T2EL was not associated with an increased risk of mortality (aHR 0.83, 95% CI 0.69-1.01, p=.057). Subgroup analysis in patients with T2EL showed that reintervention was not significantly associated with overall survival at 5-years (aHR 0.45 95%CI 0.1-1.9, p=.27).

CONCLUSIONS

T2EL occurred in nearly one-fifth of patients after EVAR and was associated with a higher rate of reintervention compared to subjects without T2EL. Yet, reinterventions were not linked to better survival. Thus, the overall benefit of reintervention for isolated T2EL in current practice remains to be defined.

Thromboembolic complications after treatment with the INCRAFT abdominal aortic aneurysm ultra-low-profile stent graft system

OBJECTIVE

Low-profile endografts have reported increased rates of limb graft occlusions. The INCRAFT stent graft system is an ultra-low-profile endograft for the exclusion of infrarenal abdominal aortic aneurysms. Our aim was to report thromboembolic events (TEs) in patients treated with the INCRAFT device and its association with risk factors.

METHODS

A retrospective study was performed of 80 patients treated with the INCRAFT endograft between February 2015 and December 2022 at a single institution. All available imaging studies were reviewed by two reviewers independently. TEs included intraprosthetic thrombus (IPT), limb graft occlusion (LGO), and distal embolization. A regression analysis was performed to evaluate possible risk factors associated with the development of TEs. These included tortuous access vessels, IPT, access vessel diameter, and the ratio between the cross-sectional area of the main body to the bilateral limb grafts.

RESULTS

Limb occlusions occurred in seven patients (9%) and 12 limbs (7.5%), resulting in a primary and secondary patency at 1, 3, and 5 years of 96% and 99%, 94% and 97%, and 89% and 93%, respectively. IPT was found in 36% of patients and affected endograft limbs in 93%. Ten distal occlusions in eight patients (10.0%) were considered to originate from IPT, which led to symptomatic occlusions of below-the-knee vessels in all patients. Freedom from IPT at 1, 3, and 4 years was 80%, 61%, and 43%, respectively. Age ≤70 years and access vessel diameter ≥10 mm were associated with IPT development. IPT was significantly associated with LGO (odds ratio, 77.10; P = .003).

CONCLUSIONS

Thromboembolic events are frequent after treatment with the INCRAFT endograft with a LGO rate of 9% per patient and IPT found in 36% of patients. IPT was more common in patients ≤70 years and was a significant risk factor for LGO.

Statistical analysis plan for the ARtificially Intelligent image fusion system versus standard treatment to guide endovascular Aortic aneurysm repair (ARIA): a multi-centre randomised controlled trial

BACKGROUND

Aortic aneurysms, a significant cause of mortality, particularly in individuals aged 55 years and older, have witnessed a transformative shift in treatment strategies with the advent of endovascular surgery. Cydar-EV is an innovative image fusion technology that can augment preoperative planning and surgical guidance of endovascular aneurysm repair (EVAR). The ARIA trial aims to evaluate the efficacy of using Cydar-EV with EVAR procedures to reduce operating time while enhancing procedural precision, patient outcomes, and cost-effectiveness. This paper describes the statistical analysis plan for the study.

METHODS/DESIGN

The ARIA trial, a phase III, multi-centre, open-label, two-armed, parallel groups randomised controlled surgical trial, seeks to recruit 340 patients diagnosed with abdominal or thoraco-abdominal aortic aneurysms. Participants are randomly assigned to receive either standard endovascular repair or an endovascular repair assisted by Cydar-EV for planning and surgical guidance. Primary and secondary outcomes are assessed at baseline, 4-12 weeks, and 52 weeks. The primary outcome measure is procedure duration at baseline, while additional secondary outcomes are recorded at various time points and include indicators for technical effectiveness, patient outcomes, procedure efficiency, and cost-effectiveness. We plan to analyse the patient outcome data according to the treatment they received regardless of initial allocation. The statistical analysis plan outlines methods for handling missing data, covariates for adjusted analyses, and planned sensitivity analyses to ensure robust evaluation of treatment effects.

TRIAL REGISTRATION

The trial was registered with the ISRCTN register on 03/12/2021, number ISRCTN13832085.

The ARIA trial protocol: a randomised controlled trial to assess the clinical, technical, and cost-effectiveness of a cloud-based, ARtificially Intelligent image fusion system in comparison to standard treatment to guide endovascular Aortic aneurysm repair

BACKGROUND

Endovascular repair of aortic aneurysmal disease is established due to perceived advantages in patient survival, reduced postoperative complications, and shorter hospital lengths of stay. High spatial and contrast resolution 3D CT angiography images are used to plan the procedures and inform device selection and manufacture, but in standard care, the surgery is performed using image-guidance from 2D X-ray fluoroscopy with injection of nephrotoxic contrast material to visualise the blood vessels. This study aims to assess the benefit to patients, practitioners, and the health service of a novel image fusion medical device (Cydar EV), which allows this high-resolution 3D information to be available to operators at the time of surgery.

METHODS

The trial is a multi-centre, open label, two-armed randomised controlled clinical trial of 340 patient, randomised 1:1 to either standard treatment in endovascular aneurysm repair or treatment using Cydar EV, a CE-marked medical device comprising of cloud computing, augmented intelligence, and computer vision. The primary outcome is procedural time, with secondary outcomes of procedural efficiency, technical effectiveness, patient outcomes, and cost-effectiveness. Patients with a clinical diagnosis of AAA or TAAA suitable for endovascular repair and able to provide written informed consent will be invited to participate.

DISCUSSION

This trial is the first randomised controlled trial evaluating advanced image fusion technology in endovascular aortic surgery and is well placed to evaluate the effect of this technology on patient outcomes and cost to the NHS.

TRIAL REGISTRATION

ISRCTN13832085. Dec. 3, 2021.

Safety of preoperative branch embolization in patients undergoing evar

The purpose of this systematic review is to evaluate the safety of pre-endovascular abdominal aortic aneurysm repair (EVAR) embolization of aortic side branches - the inferior mesenteric artery and lumbar arteries. Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were followed. A search of MEDLINE and DIMENSION databases identified 9 studies published from 2011 to 2021 that satisfied the inclusion and exclusion criteria. These studies were analyzed to detect the incidence of embolization-related complications. A total of 482 patients underwent preoperative aortic side branch embolization, 30 (6.2%) of whom suffered some kind of minor complication. The only major complication observed was ischemic colitis in 4 (0.82%) patients, two (0.41%) of whom died after bowel resection surgery. Regarding these findings, aortic side branch embolization seems to be a safe procedure, with very low percentages of both minor and major complications.

Ultrasound Particle Image Velocimetry to Investigate Potential Hemodynamic Causes of Limb Thrombosis After Endovascular Aneurysm Repair With the Anaconda Device

PURPOSE

To identify potential hemodynamic predictors for limb thrombosis (LT) following endovascular aneurysm repair with the Anaconda endograft in a patient-specific phantom.

MATERIALS AND METHODS

A thin-walled flow phantom, based on a patient's aortic anatomy and treated with an Anaconda endograft, that presented with a left-sided LT was fabricated. Contrast-enhanced ultrasound particle image velocimetry was performed to quantify time-resolved velocity fields. Measurements were performed in the same phantom with and without the Anaconda endograft, to investigate the impact of the endograft on the local flow fields. Hemodynamic parameters, namely vector complexity (VC) and residence time (RT), were calculated for both iliac arteries.

RESULTS

In both limbs, the vector fields were mostly unidirectional during the peak systolic and end-systolic velocity phases before and after endograft placement. Local vortical structures and complex flow fields were observed at the diastolic and transitional flow phases. The average VC was higher (0.11) in the phantom with endograft, compared to the phantom without endograft (0.05). Notably, in both left and right iliac arteries, the anterior wall regions corresponded to a 2- and 4-fold increase in VC in the phantom with endograft, respectively. RT simulations showed values of 1.3 to 6 seconds in the phantom without endograft. A higher RT (up to 25 seconds) was observed in the phantom with endograft, in which the left iliac artery, with LT in follow-up, showed 2 fluid stasis regions.

CONCLUSION

This in vitro study shows that unfavorable hemodynamics were present mostly in the limb that thrombosed during follow-up, with the highest VC and longest RT. These parameters might be valuable in predicting the occurrence of LT in the future.

CLINICAL IMPACT

This in-vitro study aimed to identify potential hemodynamic predictors for limb thrombosis following EVAR using ultrasound particle image velocimetry (echoPIV) technique. It was shown that unfavorable hemodynamic norms were present mostly in the thrombosed limb. Owing to the in-vivo feasibility of the echoPIV, future efforts should focus on the evaluation of these hemodynamic norms in clinical trials. Thereafter, using echoPIV as a bedside technique in hospitals becomes more promising. Performing echoPIV in pre-op phase may provide valuable insights for surgeons to enhance treatment planning. EchoPIV is also applicable for follow-up sessions to evaluate treatment progress and avoid/predict complications.

Infrarenal Abdominal Aortic Aneurysm

Abdominal aortic aneurysms are found in up to 6% of men and 1.7% of women over the age of 65 years and are usually asymptomatic. The natural history of aortic aneurysms is continued dilation leading to rupture, which is associated with an overall 80% mortality. Of the patients with ruptured aneurysms that undergo intervention, half will not survive their hospitalization. Reduction in aneurysm mortality is therefore achieved by prophylactic repair during the asymptomatic period. On a population-based level, this is supported by abdominal aortic aneurysm screening programs. Approximately 60% of abdominal aortic aneurysms are confined to the infrarenal portion of the aorta and are amenable to repair with off-the-shelf endovascular devices. Endovascular techniques have now replaced open surgery as the primary modality for aneurysm repair.

Using the Evaluating Devices Using Claims and RegisTry Data (EDUCATe) Plan within the Vascular Implant Surveillance and Interventional Outcomes Network (VISION) to Analyze the Long-Term Outcomes following Endovascular Aortic Aneurysm Repair

BACKGROUND

Implanted devices undergo clinical trials to assess their safety and effectiveness. However, pivotal device trials are limited in their follow-up while postmarket surveillance may incompletely capture late failure. Linking clinical trials to Medicare claims can address these limitations. This study matched patients from investigational device exemption (IDE) clinical trials for endovascular aortic aneurysm repair (EVAR) to Medicare claims-based registry data to compare long-term device outcomes between the 2 sources.

METHODS

Patient-level data from 2 industry-sponsored IDE trials of EVAR devices was provided by a single industry partner. Trial data were matched at the patient level to data from the Vascular Implant Surveillance and Interventional Outcomes Network (VISION), a registry that is a part of the Society for Vascular Surgery Patient Safety Organization. The primary outcomes analyzed were survival and freedom from aneurysm-related reintervention.

RESULTS

Of 159 clinical trial patients, 134 were eligible for claims-based matching and 115 (85.5%) were successfully matched to VISION registry data. For the matched cohort, the Kaplan-Meier estimated survival was 94.8% at 1 year, 82.6% at 3 years, and 68.1% at 5 years. Estimates for freedom from reintervention were 90% at 1 year, 82.4% at 3 years, and 78.1% at 5 years. The estimates for survival were nearly identical between the clinical trial data and that found in the VISION data (log-rank P = 0.89). Freedom from reintervention was similar between the groups, with IDE trial reported freedom from reintervention of 87.3% and 73.3%, compared to VISION of 92.6% and 83% at 1 and 5 years, respectively (log-rank P = 0.13).

CONCLUSIONS

Clinical trial patients who undergo EVAR can be successfully matched to claims-based registry data to improve long-term device surveillance and outcomes reporting. Claims-based results agreed well with IDE trial results for patients through 5 years, supporting the accuracy of claims-based data for longer-term surveillance. Linking clinical trial and claims-based registry data can lead to robust device monitoring.

[The Prophylaxis of Type 2 Endoleaks is Relevant for Long Term Success of EVAR]

One out of 8 patients needs a reintervention after EVAR during the first 5 years. Two thirds of secondary interventions aim at treating endoleaks. The prevalence of complications doubles in the presence of endoleaks. Fourth generation stent grafts do not lead to a decrease in Type 2-associated reinterventions, but to better prevention of Type 1 and 3 endoleaks. Pretreatment of potential type 2 feeding arteries with embolising agents and treatment of the occurrence of type 2 endoleaks.

Short-Term Re-intervention of Endovascular Abdominal Aortic Aneurysm Repair

Background and aim

Endovascular aneurysm repair (EVAR) has revolutionized the management of abdominal aortic aneurysm (AAA). The re-intervention rate following EVAR has been a subject of debate in many studies. The study aims to evaluate the short-term outcomes in terms of the early (four-year) re-intervention rate following EVAR at our centre and compare it to the average re-intervention rate of the main studies assessed by the National Institute of Health and Care Excellence (NICE).

Methods

The EVAR procedures performed over two years (2015 and 2016) were retrieved using the operation codes. The clinical portal and PACS systems were used to review the discharge summaries, clinic and multidisciplinary team (MDT) letters, as well as the scans and interventional radiology procedures to assess the patients’ adherence to follow-up and identify any re-intervention procedure done to correct underlying problems related to the EVAR performed. Patients who switched their follow-up to another hospital were contacted and interviewed about any re-intervention undergone. 

Results

A total of 108 patients underwent EVAR during the two-year study period. Twenty EVAR-related re-interventions (18.5%) were recorded, irrespective of the cause or the type of intervention. This is slightly higher than the average rate by NICE (16.89%). Type 1 endoleak represented the leading cause for re-intervention (30%). Most of the cases of re-intervention were done endovascularly (60%). Forty-five percent of the patients had a re-intervention during the first year and 35% in the third year.

Conclusion

This study shows that although our re-intervention rate following EVAR was slightly higher than the international average, EVAR is still a safe method for the repair of AAA with relatively low peri-operative morbidity and mortality. However, long-term follow-up of these patients is mandatory as re-interventions are frequently required. Nonetheless, the majority of re-interventions can be done with minimal morbidity to the patient.

Effect of Abdominal Aortic Aneurysm Size on Mid-Term Mortality After Endovascular Repair

BACKGROUND

Previous studies have suggested that large preoperative AAA size may impact late survival after elective EVAR. It is unclear, however, whether this association applies to patients with smaller AAA between 5.0-5.5 cm, who constitute a substantial portion of patients undergoing elective EVAR. The purpose of this study was to delineate the effect of AAA size between 5.0 and 5.5 cm on mid-term mortality after EVAR by analyzing a large national cohort, the Vascular Quality Initiative (VQI) database.

METHODS

Using the Vascular Quality Initiative (VQI) national database, patients who underwent EVAR for intact AAA between 2003 and 2018 were identified and stratified based on maximal AAA diameter into 3 groups: Group 1 (4.0 cm ≤ AAA <5.0 cm); Group 2 (5.0 cm ≤ AAA < 5.5 cm); and Group 3 (AAA ≥ 5.5 cm). Cox proportional hazard model and propensity score matching method were used to estimate AAA size effect on all-cause mortality at 1, 3, and 5 years after EVAR while adjusting for potential confounders.

RESULTS

The study included 32,398 patients, of whom 81% were men with a mean age of 74. The most common group who underwent EVAR was Group 2 (5.0 cm ≤ AAA < 5.5 cm). Larger AAA size was associated with male sex (75% versus 79% versus 84%, for Groups 1, 2, and 3 respectively; P < 0.0001) and with coronary artery disease (27% versus 29% versus 31%, for Groups 1, 2, and 3 respectively, P< 0.0001); but was negatively associated with active smoking (33% versus 31% versus 30%, for Groups 1, 2, and 3, respectively, P< 0.001). While 10% of the largest and smallest AAA groups (Groups 3 and 1, respectively) were symptomatic, only 5% of patients in Group 2 were symptomatic (P < 0.01). Adjusted Cox proportional hazard modeling revealed that patients in Group 2 were at significantly lower risk of 5-year mortality when compared to patients in Group 3 (HR 0.66, 95% CI 0.61-0.72, P< 0.01), while similar in risk when compared to patients in Group 1 (HR 1.11, 95% CI 0.93-1.32, P= 0.26).

CONCLUSION

Our analysis found that over 40% of EVAR in the national VQI cohort were performed for AAA < 5.5 cm, with the greatest number of patients undergoing EVAR at AAA size 5.0-5.5cm. Patients with AAA size 5.0-5.5 cm had better 5-year survival outcomes than patients with AAA ≥ 5.5 cm, and similar survival to patients with small AAA between 4.0-5.0 cm.

Laparoscopic lumbar artery ligation of type II endoleaks following endovascular aneurysm repair: A case report

INTRODUCTION

Although the clinical significance of type II endoleaks remain controversial, management strategies continue to expand. The laparoscopic approach is a minimally invasive method for persistent type II endoleak repair after endovascular aneurysm repair.

PATIENT CONCERNS

A 70 - year - old male patient with a history of endovascular aneurysm repair with left internal iliac artery embolization presented with persistent type II endoleak from the lumbar arteries 2 years ago. The aneurysm sac size had increased more than 10 mm during follow up period.

DIAGNOSIS

Persistent type II endoleak after endovascular aneurysm repair.

INTERVENTIONS

Transarterial embolization was attempted and failed. A minimally invasive laparoscopic lumbar artery ligation was then utilized.

OUTCOMES

The patient was discharged without any complications after surgery. Follow-up computed tomography angiography has shown the complete disappearance of the type II endoleaks.

CONCLUSIONS

Laparoscopic lumbar artery ligation may be a safe and effective alternative treatment for type II endoleaks, especially in high resource settings.

A morphovolumetric analysis of aneurysm sac evolution after elective endovascular abdominal aortic repair

OBJECTIVE

Abdominal aortic aneurysm (AAA) sac shrinkage after endovascular aortic repair (EVAR) has been regarded as positive marker of EVAR success durability. The purpose of this study was to describe the morphovolumetric changes of the AAA sac during follow-up after elective EVAR and to analyze sac shrinkage-related variables.

METHODS

This is a single-center, retrospective, observational cohort study from a tertiary referral university hospital. All patients treated with EVAR between January 2013 and December 2018 were identified. Inclusion criteria were elective EVAR for AAA, preoperative computed tomography angiography within 6 months before EVAR and at least one postoperative computed tomography angiography during the follow-up, using a standardized protocol. Aneurysm sac shrinkage was defined as diameter decrease of 1 cm or more, volume shrinkage threshold was identified by a 16% decrease compared with the preoperative value. Primary outcomes were early (≤30 days) and late survival, and freedom from aneurysm-related mortality (ARM), and aortic reintervention.

RESULTS

There were 149 of the 325 patients (45.8%) who met the inclusion criteria: 133 (89.3%) were male and 16 (10.7%) female. The mean age was 74 ± 7 years (range, 55-87 years); the median AAA diameter was 56 mm (interquartile range, 50.0-61.2 mm) and the median volume was 138.8 cm³ (range, 99.0-178.3 cm³). Primary technical success was achieved in 145 patients (97.3%). The in-hospital mortality rate was 1.3%. The median follow-up was 42 months (interquartile range, 22.5-58.0 months). Both AAA diameter and volume decreased (P = .001 and P = .035, respectively) compared with preoperative measurements. Diameter shrinkage was adjudicated in 27 patients (18.1%), volume shrinkage was observed in 42 patients (28.2%). A Cox regression analysis demonstrated an association between the AAA diameter shrinkage and the preoperative diameter (P = .002; hazard ratio, 1.03; 95% confidence interval [CI], 1.011-1.052). The presence of a persistent endoleak predicted the absence of volume shrinkage (P = .001; hazard ratio, 7.75; 95% CI, 2.282-26.291). The estimated freedom from ARM was 97.5 ± 1.0% (95% CI, 93-99) at 12 months, and 96 ± 2% (95% CI, 90-98) at both 36 and 60 months. Aortic reintervention during the follow-up period was necessary in 7 patients (4.7%). ARM was only observed in the group characterized by the concomitant absence of diameter and volume shrinkage.

CONCLUSIONS

Volumetric analysis showed to have higher sensitivity than the simple two-dimensional measurement of the diameter to study AAA sac changes after EVAR. Although no predictor was found to be associated with AAA volume shrinkage, ARM occurred only in the group of AAAs with the absence of volume shrinkage.

Results of adjunctive stenting with high-radial force stents to prevent or treat limb occlusion after EVAR

BACKGROUND

The aim of this study was to report the results of a multicenter experience on the use of adjunctive stents deployed inside abdominal aortic endografts with the purpose to prevent or treat limb occlusion after endovascular aneurysm repair (EVAR).

METHODS

Between 2010 and 2018, there were 35 patients with aorto-iliac aneurysm presenting one or more risk factors for endograft limb occlusion (narrow aortic bifurcation and/or stenotic, highly angulated or occluded iliac arteries), who were treated with standard bifurcated stent graft reinforced by the means of a single model of balloon-expandable platinum/iridium bare stent (CP Stent; NuMED, Inc., Hopkinton, NY, USA). Technical success, mortality, limb patency and reintervention rate during follow-up were the main endpoints assessed.

RESULTS

Technical success was 100%. No patients died perioperatively and no major complication was registered. During a mean follow-up of 48 months (range 1-87), neither aortic-related death nor secondary intervention was registered. At a mean follow-up imaging of 39.4 months (range 1-81) no endograft limb lost its patency.

CONCLUSIONS

The use of high-radial force balloon-expandable stents deployed inside bifurcated endografts to prevent or treat limb occlusion is a safe and effective adjunctive procedure, with outstanding long-term outcomes in terms of patency and reinterventions.

Review of Type III Endoleaks

Endoleak remains a significant challenge to endovascular aneurysm repair, particularly as evolving techniques and devices have allowed treatment of increasingly complex aneurysm anatomy with increasing number of device components. Intervention is recommended for both type I and III endoleaks due to their risk of rupture, and endovascular techniques are the favored modality with placement of a bridging endograft over the endoleak defect. Conversion to open surgical repair remains the definitive option in cases where less invasive methods have failed or are precluded. In this article, the authors review evidence on the etiology, incidence, diagnosis, and current techniques for type III endoleak management.

Midterm evaluation of perigraft arterial sac embolization in endovascular aneurysm repair

OBJECTIVE

Management of clinically significant endoleaks (ELs) remains costly, time-consuming, and morbid. Unresolved ELs can result in rupture and mortality after endovascular aneurysm repair (EVAR). Perigraft arterial sac embolization (PASE) has been used to treat ELs diagnosed at the time of EVAR or during surveillance.

METHODS

A retrospective review of prospectively maintained databases was conducted. The databases were compiled from two institutions between 2006 and 2016. PASE was performed for type I, type II, or type III EL with a thrombin, contrast medium, and Gelfoam (Pfizer, New York, NY) slurry prepared as previously described. PASE was administered either at the time of EVAR (primary) or during surveillance (secondary). Safety end points included nontarget embolization, defined as neurologic or enteric clinical sequelae from lumbar artery or visceral artery embolization, allergic reaction, peripheral embolization, or rupture. Efficacy end points included successful resolution of EL and cessation of aneurysm sac growth on computed tomography (CT) scans with contrast enhancement.

RESULTS

A total of 66 patients included in the study were treated with PASE. Primary PASE was performed in 38 patients (58%) and secondary in 28 (42%). Within the total cohort, the average clinical and CT scan follow-up was 1.7 years (0.1-11.6 years). Four patients required open repair for residual high-pressure ELs (one type IIIB and three type I; 6%). Of the 95% of patients who did not require open conversion, aneurysm growth did not occur during the follow-up period. In the overall cohort, PASE was successful in 88% of type I EL and 73% of patients with type II EL. There was no evidence of recanalization after thrombosis of culprit vessel for EL. No patients suffered nontarget embolization, spinal ischemia, allergic reaction, post-EVAR rupture, or colonic ischemia.

CONCLUSIONS

Primary and secondary PASE proved to be a safe, effective, and durable tool in sac management in conjunction with EVAR. Treating ELs during or after EVAR with PASE has minimized the incidence of EL on CT scan and halted aneurysm growth in our cohort. Further studies are needed to confirm the long-term durability of PASE in reducing secondary interventions after EVAR.

Postoperative surveillance and long-term outcome after endovascular aortic aneurysm repair in the Netherlands: study protocol for the retrospective ODYSSEUS study

INTRODUCTION

Strict imaging surveillance protocols to detect complications following endovascular aneurysm repair (EVAR) are common practice. However, controversy exists as to whether all EVAR patients need intense surveillance. The 2019 European Society for Vascular Surgery guidelines for management of abdominal aortic aneurysm (AAA) suggest that patients may be considered for limited follow-up with imaging if classified as 'low risk' for complications based on their initial postoperative imaging. The current study aims to investigate the intervention-free survival and overall survival stratified for patients with and without yearly imaging surveillance.

METHODS AND ANALYSIS

The Observing a Decade of Yearly Standardised Surveillance in EVAR patients with Ultrasound or CT Scan study comprises a national multicentre retrospective cohort study in 17 medical centres. Consecutive patients with an asymptomatic or symptomatic infrarenal AAA who underwent EVAR between January 2007 and January 2012 will be included in this study with follow-up until December 2018. Clinical variables and all follow-up information will be retrieved in extensive data collection from the patient's medical records. In addition, an e-survey was sent to vascular surgeons at the 17 participating centres to gauge their opinions regarding the possibility of safely reducing the frequency of imaging surveillance. Primary endpoints are intervention after EVAR and aneurysm-related mortality. The initial estimated sample size is 1997 patients.

ETHICS AND DISSEMINATION

The study has been approved by the Medical Ethics Review Committee of the Amsterdam UMC, location Academic Medical Centre, Amsterdam, the Netherlands. Study findings will be disseminated via presentations at conferences and publications in peer-reviewed journal.

TRIAL REGISTRATION NUMBER

The Netherlands Trial Registry, NL6953 (old: NTR28773).

Clinical and anatomical variables associated in the literature to limb graft occlusion after endovascular aneurysm repair compared to the experience of a tertiary referral center

INTRODUCTION

Limb graft occlusion (LGO) is the third reason for hospital readmission after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm. We reviewed the clinical features, incidence, anatomical and devices related predictive factors for LGO after EVAR, and compared them with our experience.

EVIDENCE ACQUISITION

EVAR between 2010-2017 were included. Patients with LGO (LGO group) were matched for age and type of endograft with the rest of the entire cohort without LGO (control group). Clinical, anatomical, operative, outcome, and follow-up data were collected.

EVIDENCE SYNTHESIS

Two hundred seventy-six EVAR, (30 aorto-uniliac), 276 patients. The incidence of LGO was 2.5% (seven limbs, seven patients) at 27±24.6 days. Symptomatic patients were successfully treated. No mortality, limb loss, critical limb ischemia or residual claudication due to LGO was observed. Fifty patients resulted from the matching. Among the predictive factors of LGO between the two groups, significant differences were observed in graft limb oversizing ≥15% (57.1% vs. 8%, P=0.005), or kinking (42.9% vs. 2%, P=0.01), and diameter of the aortic bifurcation <20 mm (71.4% vs. 20%, P=0.01). Logistic regression analysis showed that these three variables increased the risk of LGO (P=0.003, P=0.006, and P=0.01, respectively).

CONCLUSIONS

The strongest predictive factors of LGO issued from our review were: extension in the external iliac artery, or small diameter; tortuous, angled, and calcific iliac axis; excessive oversizing of the limb graft, or kinking; use of old generation devices; EVAR performed outside the instructions for use. Limb graft oversizing >15%, or kinking, and aortic bifurcation <20 mm appear to be independent predictive factors of LGO.

A clinical update on the mid-term clinical performance of the Ovation endograft

INTRODUCTION

The Ovation stent-graft uncouples the steps of fixation and sealing via a pair of polymer-filled inflatable rings. Apart from the well-documented early results, newer data emerged for mid-term results of Ovation and are presented in this review.

AREAS COVERED

Aim of this article was to report all current studies with the mid-term results of the particular endograft, the incidence of complications and failure, and discuss their management.

EXPERT COMMENTARY

The Ovation stent-graft exhibits very satisfactory clinical mid-term results in abdominal aortic aneurysms treated within the instructions-for-use. It can also have a very promising role in challenging neck anatomies with conical shape and presence of thrombus or calcification. However, this should be not considered a panacea and long-term results are needed to validate this intriguing aspect.

Type 2 Endoleak Incidence and Fate After Endovascular Aneurysms Repair in a Multicentric Series: Different Results with Different Devices?

BACKGROUND

The aim of this work is describing incidence and fate of type 2 endoleaks (T2ELs) in a multicentric cohort of patients treated by endovascular aneurysms repair using the Ovation device (Endologix) and comparing them with a group treated using the Excluder (W. L. Gore & Associates).

METHODS

This is a retrospective study conducted on 261 patients treated using the Ovation device and 203 using the Excluder. Outcomes were intraprocedural, 30-day, 12-month, and mean time follow-up T2EL incidence and related reinterventions. Patent inferior mesenteric artery (IMA), ≥3 lumbar arteries (LAs), intrasac thrombus volume, the mean diameter of common and external iliac arteries, external iliac artery stenosis (>70%), diameter ≤5 mm, iliac tortuosity ratio ≤0.5, thrombosis, and calcification were noted and considered as potentially influencing outcomes.

RESULTS

Patients of the Ovation group presented significantly more thrombosed, calcified, and tortuous iliac vessels than those in the Excluder group. No significant differences were noted in sac thrombosis, IMA, and LA patency. At completion angiography, T2EL was evident in 57 Ovation and 46 Excluder patients (P = 0.832). At 1 month, it was evident in 33 Ovation group and 28 Excluder group patients (P = 0.726). At 12-month and mean time (30.14 months) follow-up, no differences were evident between the 2 groups (P = 0.940 and 0.951, respectively). The log-rank test showed that the rate of T2EL-related reintervention was not different between the 2 groups (P = 0.46). Regarding anatomical characteristics, a statistically significant difference was not observed between patients presenting or not with T2EL (P > 0.05).

CONCLUSIONS

Data showed no significant differences in terms of T2EL incidence between the 2 study groups. None of preoperative anatomical features were found to be significantly associated with the appearance of T2EL.

Laparoscopic ligation of Type II endoleaks following endovascular aneurysm repair: A systematic review

INTRODUCTION

The clinical significance of Type II endoleak remains contentious; the strategies used for its management have continued to expand. We systematically review the literature and comprehensively appraise the effectiveness of laparoscopic intervention in the management of this common complication.

METHODS

A systematic search was performed in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines on MEDLINE, EMBASE and Cochrane Library for relevant articles reporting laparoscopic surgery of Type II endoleak post-endovascular aortic repair.

RESULTS

Thirteen studies representing 40 patients were investigated. Mean age was 72.7 years, and proportion of males was 90.0%. All patients were American Society of Anesthesiologists grade II and above and underwent standard infrarenal endovascular aneurysm repair. The mean duration of operation was 130.2 min, with a mean blood loss across of 173.8 mL. The overall technical success rate was 90% (27/30). Two patients required reoperation within 24 h, with further lumbar ligations that were successful. One other patient required conversion to open surgery due to significant bleeding at the dorsal aorta. The perioperative and 30-day mortality rate was 2.5% (1/40). The mean length of hospital stay was 3.7 days (range 1 to 10 days). The mean length of follow-up was 36.7 months (range 3 to 103.2 months), where the rate of recurrence was 22.5% (9/40).

CONCLUSIONS

Laparoscopic ligation of feeding vessels causing Type II endoleak is potentially an alternative treatment after failed standard endovascular embolization, particularly in select centres with necessary resources and capabilities.

Abdominal aortic aneurysms

An abdominal aortic aneurysm (AAA) is a localized dilatation of the infrarenal aorta. AAA is a multifactorial disease, and genetic and environmental factors play a part; smoking, male sex and a positive family history are the most important risk factors, and AAA is most common in men >65 years of age. AAA results from changes in the aortic wall structure, including thinning of the media and adventitia due to the loss of vascular smooth muscle cells and degradation of the extracellular matrix. If the mechanical stress of the blood pressure acting on the wall exceeds the wall strength, the AAA ruptures, causing life-threatening intra-abdominal haemorrhage - the mortality for patients with ruptured AAA is 65-85%. Although AAAs of any size can rupture, the risk of rupture increases with diameter. Intact AAAs are typically asymptomatic, and in settings where screening programmes with ultrasonography are not implemented, most cases are diagnosed incidentally. Modern functional imaging techniques (PET, CT and MRI) may help to assess rupture risk. Elective repair of AAA with open surgery or endovascular aortic repair (EVAR) should be considered to prevent AAA rupture, although the morbidity and mortality associated with both techniques remain non-negligible.

Selective Inferior Mesenteric Artery Embolization during Endovascular Abdominal Aortic Aneurysm Repair to Prevent Type II Endoleak

PURPOSE

The purpose of this study was to evaluate the efficacy of simultaneous IMA (s-IMA) embolization during the endovascular abdominal aortic aneurysm repair (EVAR).

MATERIALS AND METHOD

From July 2007 to January 2011, 189 patients in the no embolization (NE) group underwent EVAR without the indication for s-IMA embolization. Since February 2011 to April 2014, 143 patients have undergone EVAR. Among these patients, 26 patients underwent s-IMA embolism under a predefined indication and constituted the simultaneous embolization (SE) group. The indications for s-IMA embolization were defined by preoperative computed tomography (CT) findings, as follows: (1) the diameter was greater than 2.5 mm and (2) no stenosis due to thrombus or calcification at its orifice.

RESULTS

The incidence of a type II endoleak from the IMA was 3.4% (5/143) in the SE group patients and 13.2% (25/189) in the NE group patients (p = 0.013), and the incidence of a type II endoleak from all branches (i.e., IMA, lumbar, medial sacral arteries) was 15.4% (22/143) in the SE group patients and 32.3% (61/189) in the NE group patients (p = 0.0003). During the follow-up period (range, 6-72 months; mean: 28 months), the reintervention rate for a type II endoleak from the IMA and/or other branches was 9.5% (18/189) in the NE group and 0.6% (1/143) in the SE group (p = 0.0001).

CONCLUSION

In selected patients, performing an s-IMA embolization, based on CT findings, decreased the incidence of a type II endoleak and reintervention from the IMA and from all branches.

Early outcomes with a single-sided access endovascular stent

OBJECTIVE

The objective of this study was to report the 1-year follow-up study results of the new Horizon stent graft (Endospan, Herzliya, Israel) from two different prospective consecutive trials. The Horizon abdominal aortic aneurysm stent graft system is a 14F profile system requiring only a single access site. It consists of three modules, introduced separately: base limb (iliac to iliac limb); distal aortic limb; and proximal aortic limb with a bare suprarenal crown and active fixation.

METHODS

Data from the first in man (FIM) clinical study with 10 patients enrolled and the pivotal study with 30 patients were analyzed. Outcomes measured were freedom from major adverse events (MAEs) including all-cause mortality, myocardial infarction, renal failure, respiratory failure, paraplegia, stroke, bowel ischemia, and procedural blood loss ≥1000 mL. Performance end points included successful delivery and deployment of the device, freedom from aneurysm growth ≥5 mm, type I or type III endoleak, stent graft occlusion, conversion to open surgery, rupture, and stent graft migration.

RESULTS

In the FIM study, one conversion to open surgery with >1000 mL of blood loss was registered perioperatively. In the pivotal study, no perioperative MAE was registered. Overall, at 1-year follow-up, two deaths and one aneurysm growth unrelated to endoleak were registered.

CONCLUSIONS

The results of both the FIM and pivotal studies demonstrated that 39 of 40 procedures were successful for delivery and deployment of the Horizon stent graft. No MAE was registered during the follow-up. The primary safety and performance end points were met in both studies.

Embo-EVAR: A Technique to Prevent Type II Endoleak? A Single-Center Experience

BACKGROUND

Intraprocedural aneurysm sac embolization (embo-EVAR) during endovascular abdominal aneurysm repair (EVAR) using coils and fibrin glue is a technique for preventing type II endoleak (EII). Our aim is to evaluate feasibility, safety and clinical outcome of this promising approach.

MATERIALS AND METHODS

A retrospective clinical case analysis of 72 patients who underwent EVAR during the period 2011-2014. Two groups were compared at 6 and 12 months follow-up with contrast media computed tomography scan and contrast-enhanced ultrasound (CEUS) imaging: consecutively, 36 patients (group A) treated with classic EVAR and 36 patients (group B) treated with embo-EVAR. Coils were released filling better as possible the aneurysm sac; the embolization was completed by injecting fibrin glue. Device and materials used, differential systemic and sac pressures, presence of any endoleak, and complication were registered.

RESULTS

In our experience, we had 100% technical success without surgical conversion. Embo-EVAR was performed, after endograft deployment, in group B patients, all with ratio of Δ-pressures (obtained from Δ-sac pressure/Δ-differential pressure) > 0.16. No early or late complications occurred and mortality was nil. Follow-up was performed with computed tomography-angiography and CEUS at 6 and 12 months. We observed 9 type II and 1 type Ia endoleak in group A and 2 type II and 1 type Ib endoleaks in group B. Mean radiation exposure time was 30.3 min in group A and 43.3 min in group B. EVAR procedure average cost was 9,000 €. The average cost of sac embolization was 1,500€.

CONCLUSIONS

Although a randomized study is necessary, embo-EVAR may be a valid approach to prevent type II endoleaks and further complications. Mild costs and exposure-dose increase could be accepted to avoid reinterventions, and in our experience, it could be routinely performed with excellent results.

Preoperative risk factors for aneurysm sac expansion caused by type 2 endoleak after endovascular aneurysm repair

Purpose

The objective of this study was to investigate the preoperatively definable risk factors which predict the aneurysm sac expansion caused by persistent type 2 endoleak after endovascular aneurysm repair.

Methods

Between 2008 and 2014, retrospective analysis was performed to examine the predictive risk factors for aneurysm sac enlargement caused by persistent type 2 endoleak, which was defined as a continuous endoleak present for more than six months. Aneurysm sac expansion was diagnosed if the maximum transverse diameter increased by 5 mm or more compared with the preoperative measurement.

Results

During the study period, endovascular aneurysm repair was performed in 211 patients with abdominal aortic aneurysm and common iliac artery aneurysm. Sac enlargement for type 2 endoleaks was observed in 20 patients (9.5%). The presence of more than five patent lumbar arteries flowing into aneurysm sac in the preoperative computed tomography (hazard ratio, 3.37; 95% confidence interval, 1.24–10.8; p = 0.017) was a predictive factor for sac expansion caused by persistent type 2 endoleak on Cox regression analysis. The presence of a patent inferior mesenteric artery was not associated with the sac expansion caused by persistent type 2 endoleak.

Conclusions

The presence of more than five lumbar arteries flowing into the aneurysm sac was a preoperative risk factor for sac expansion caused by persistent type 2 endoleak.

Factors that affect cost and clinical outcome of endovascular aortic repair for abdominal aortic aneurysm

OBJECTIVE

This study evaluated the effect of indication for use (IFU), additional graft components, and percutaneous closure of endovascular aortic repair (PEVAR) on clinical outcomes and cost of endovascular aortic repair (EVAR).

METHODS

Clinical and financial data were obtained for all elective EVARs completed at a university-affiliated medical center between January 2012 and June 2013. Data were analyzed by χ², Student t-test for independent samples, and Kaplan-Meier survival.

RESULTS

There were 67 elective EVARs. Additional cuffs/extensions were used in 37%, increasing the baseline graft cost by 36% (P < .001), total costs by 20% (P < .001), and negatively affecting the contribution margin. Aortic neck IFU (P = .02), failure of the index graft to seal the neck (P = .02), and need for an additional cuff (P = .008) were related to the need for reintervention for type Ia endoleak for graft B (Excluder; W. L. Gore and Associates, Flagstaff, Ariz), whereas limb IFU was related to the need for additional limb extension for graft A (Powerlink; Endologix, Irvine, Calif; P < .001). Limb extension (P = .06) and failure of the index graft to provide an adequate seal (P < .001) were associated with reintervention for type Ib endoleak. Reintervention-free rates at 24 months were 96% for graft A and 94% for graft B (P =.54), but different patterns in reintervention emerged: graft A required reoperation early (<2 months) then stabilized; graft B did not require reintervention until 24 months, but rates increased substantially by 25 months. PEVAR was attempted in 61 (91%): 49 (73%) bilaterally, 7 (10%) unilaterally, and 5 (8%) failed. The mean number of closure devices was four (range, 1-9): $1000 (3.5% of total cost). Bilateral PEVAR was associated with shorter operating time than unilateral PEVAR/failed PEVAR (P < .001) and lower operating room use costs (P = .005) and total hospital costs (P = .003) than failed PEVAR. The contribution margin was higher for bilateral PEVAR than unilateral PEVAR/failed PEVAR (P = .005). Patients with bilateral PEVAR and unilateral PEVAR were more often discharged on postoperative day 1 than those with failed PEVAR (P = .002). Hospital length of stay (P = .49), operating room duration (P = .31), and total costs (P = .72) were similar for unsuccessful PEVAR and EVAR completed with cutdown.

CONCLUSIONS

Higher rates of reintervention occurred when EVAR was performed outside of IFU guidelines or when additional components were needed. Additions raised graft costs significantly above baseline. Notable differences in graft performance in complex anatomy and varied patterns of reoperation could be useful in the graft selection process to improve outcome and contain costs. Bilateral PEVAR was associated with lower costs and postoperative day 1 discharge. Attempting PEVAR may be reasonable unless there is serious concern for failure.

Advantages of contrast-enhanced ultrasonography over computed tomography for the detection of persistent type II endoleak after embolization: A case report

The aim of this case report is to describe the use of contrast-enhanced ultrasonography in the detection of a type II endoleak after prior embolization with Onyx. A 74-year-old male patient with hypertension previously underwent endovascular repair of a 7.1-cm infrarenal aortic aneurysm. CT angiography surveillance revealed a type II endoleak associated with aneurysm sac expansion. Selective transarterial embolization of the endoleak was performed, but it was not possible to detect the persistent endoleak using CT angiography because of image artifacts caused by Onyx. Contrast-enhanced ultrasonography enabled us to detect the persistent endoleak in this patient. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:522-526, 2016.

Intervention after endovascular aneurysm repair: Endosalvage techniques including perigraft arterial sac embolization and endograft relining

Endovascular aneurysm repair (EVAR) has revolutionized the treatment of abdominal aortic aneurysm (AAA). However, persistent AAA sac endoleak following EVAR can result in sac diameter increase requiring re-intervention in up to one-third of cases and even result in aneurysm rupture. In this case review, we summarize and detail endovascular re-interventions for each type of endoleak. We also detail specific options including stent-graft relining for indeterminate, Type III, and Type IV endoleaks and perigraft arterial sac embolization to induce thrombosis and resolve acute Type I, II, or III endoleaks. Endograft relining involves placement of a new stent-graft-elevating the bifurcation and extending the repair from renal artery to hypogastric arteries; perigraft arterial sac embolization involves placement of a catheter into the excluded sac from common femoral artery access, characterization of the inflow and outflow of the endoleak, and inducing cessation of the blood flow into the sac by the administration of thrombogenic material. Endoleaks range from low-pressure endoleaks, which can be safely monitored in a surveillance program to high-pressure endoleaks, which mandate intervention when associated with AAA sac diameter increase to protect from rupture. The evaluation of new devices and techniques to treat endoleak after EVAR remains an important issue in patient care after EVAR.

Outcomes of type II endoleaks after endovascular abdominal aortic aneurysm (AAA) repair: a single-center, retrospective study

PURPOSE

This study aims to determine incidence and outcomes of type II endoleaks (T2E) after endovascular abdominal aortic aneurysm repair (EVAR).

METHODS

A retrospective review of procedural angiograms, computed tomography angiography, and medical records of 202 patients who underwent EVAR with the Gore Excluder stent graft was performed to determine presence and outcomes of T2E.

RESULTS

Median follow-up time for 163 patients meeting inclusion criteria [136 males (83%)] was 24.7 months (range=0.5-85.2 months). T2E occurred in 66/163 patients (40.5%). Aneurysm sac size was unchanged in 32/66 patients (48.5%), decreased in 22/66 (33.3%), and increased in 12/66 (18.2%). No aneurysm ruptures, conversion to open repair, or aneurysm-related deaths occurred.

CONCLUSION

T2E are a common occurrence after EVAR, often with benign outcome. However, routine surveillance should be performed, particularly in patients with persistent endoleak or sac growth.

Risk factors and consequences of persistent type II endoleaks

OBJECTIVE

Type II endoleaks are common after endovascular aneurysm repair (EVAR), but their clinical significance remains undefined and their management controversial. We determined risk factors for type II endoleaks and associations with adverse outcomes.

METHODS

We identified all EVAR patients in the Vascular Study Group of New England abdominal aortic aneurysm database. Patients were subdivided into two groups: (1) those with no endoleak or transient type II endoleak and (2) persistent type II endoleak or new type II endoleak (no endoleak at completion of case). Patients with other endoleak types and follow-up shorter than 6 months were excluded. Multivariable analysis was used to evaluate predictors of persistent or new type II endoleaks. Kaplan-Meier and Cox regression analysis were used to evaluate predictors of reintervention and survival.

RESULTS

Two thousand three hundred sixty-seven EVAR patients had information on endoleaks: 1977 (84%) were in group 1, of which 79% had no endoleaks at all, and 21% had transient endoleaks that resolved at follow-up. The other 390 (16%) were in group 2, of which 31% had a persistent leak, and 69% had a new leak at follow-up that was not seen at the time of surgery. Group 2 was older (mean age, 75 vs 73 years; P < .001) and less likely to have chronic obstructive pulmonary disease (COPD; 24% vs 34%; P < .001) or elevated creatinine levels (2.6% vs 5.3%; P = .027). Coil embolization of one or both hypogastric arteries was associated with a higher rate of persistent type II endoleaks (12 vs 8%; P = .024), as was distal graft extension (12% vs 8%; P = .008). In multivariable analysis, COPD (odds ratio [OR], 0.7; 95% confidence interval [CI], 0.5-0.9; P = .017) was protective against persistent type II endoleak, while hypogastric artery coil embolization (OR, 1.5; 95% CI, 1.0-2.2; P = .044), distal graft extension (OR, 1.6; 95% CI, 1.1-2.3; P = .025), and age ≥ 80 (OR, 2.7; 95% CI, 1.4-5.3; P = .004) were predictive. Graft type was also associated with endoleak development. Persistent type II endoleaks were predictive of postdischarge reintervention (OR, 15.3; 95% CI, 9.7-24.3; P < .001); however, they were not predictive of long-term survival (OR, 1.1; 95% CI, 0.9-1.6; P = .477).

CONCLUSIONS

Persistent type II endoleak is associated with hypogastric artery coil embolization, distal graft extension, older age, the absence of COPD, and graft type, but not with aneurysm size. Persistent type II endoleaks are associated with an increased risk of reinterventions, but not rupture or survival. This reinforces the need for continued surveillance of patients with persistent type II endoleaks and the importance of follow-up to detect new type II endoleaks over time.

Lack of Iliac Engagement Correlates With Iliac Limb Complications Following Standard EVAR

Objective:

An adequate distal sealing zone is a prerequisite for successful endovascular aneurysm repair (EVAR). Poor engagement of iliac limbs within the common iliac artery potentially increases the risk of limb-related complications. The aim of this study was to investigate the proportion of common iliac artery used for distal sealing as a predictor of iliac limb complications following standard EVAR.

Methods:

This was a retrospective case controlled study where an iliac complication group was compared to a larger control group from the unit database. Core analysis of postoperative computed tomography scans was used to ascertain the percentage engagement of the iliac limb of the stent graft within the native iliac artery in both groups.

Results:

There were 240 limbs in the control group and 33 limbs in the complications group. Complications included 10 endoleaks, 1 iliac limb dislocation, 2 insufficient engagement, 4 occlusions, and 16 kinks. The proportion of common iliac artery engagement was significantly higher in the control group compared with the complications group (75.3:68.6%, P = .003).

Conclusions:

Increased engagement in the common iliac artery following standard EVAR reduces the risks of limb complications. A clinical guide utilization of more than 70% of the total length of common iliac artery could be used as this was associated with a significantly lower rate of iliac limb complications following standard EVAR.

A multiregional registry experience using an electronic medical record to optimize data capture for longitudinal outcomes in endovascular abdominal aortic aneurysm repair

OBJECTIVE

Registries have been proven useful to assess clinical outcomes, but data entry and personnel expenses are challenging. We developed a registry to track patients undergoing endovascular aortic aneurysm repair (EVAR) in an integrated health care system, leveraging an electronic medical record (EMR) to evaluate clinical practices, device performance, surgical complications, and medium-term outcomes. This study describes the registry design, data collection, outcomes validation, and ongoing surveillance, highlighting the unique integration with the EMR.

METHODS

EVARs in six geographic regions of Kaiser Permanente were entered in the registry. Cases were imported using a screening algorithm of inpatient codes applied to the EMR. Standard note templates containing data fields were used for surgeons to enter preoperative, postoperative, and operative data as part of normal workflows in the operating room and clinics. Clinical content experts reviewed cases and entered any missing data of operative details. Patient comorbidities, aneurysm characteristics, implant details, and surgical outcomes were captured. Patients entered in the registry are followed up for life, and all relevant events are captured.

RESULTS

Between January 2010 and June 2013, 2112 procedures were entered in the registry. Surgeon compliance with data entry ranges from 60% to 90% by region but has steadily increased over time. Mean aneurysm size was 5.9 cm (standard deviation, 1.3). Most patients were male (84%), were hypertensive (69%), or had a smoking history (79%). The overall reintervention rate was 10.8%: conversion to open repair (0.9%), EVAR revision (2.6%), other surgical intervention (7.3%). Of the reinterventions, 27% were for endoleaks (I, 34.3%; II, 56.9%; III, 8.8%; IV and V, 0.0%), 10.5% were due to graft malfunction, 3.4% were due to infection, and 2.3% were due to rupture.

CONCLUSIONS

Leveraging an EMR provides a robust platform for monitoring short-term and midterm outcomes after abdominal aortic aneurysm repair. Use of standardized templates in the EMR allows data entry as part of normal workflow, improving compliance, accuracy, and data capture using limited but expert personnel. Assessment of patient demographics, device performance, practice variation, and postoperative outcomes benefits clinical decision-making by providing complete and adjudicated event reporting. The findings from this large, community-based EVAR registry augment other studies limited to perioperative and short-term outcomes or small patient cohorts.

Vascular ultrasonography for follow-up of endovascular repair of abdominal aorta aneurysms

BackgroundThere is little information available on follow-up of abdominal aortic aneurysm patients treated with endovascular repair using vascular ultrasonography in Brazil or on how it compares with the results of angiotomography. Since ultrasonography is an examination that is risk-free, inexpensive and widely available, it is a very attractive method. In this study we attempted to evaluate the sensitivity and specificity of vascular ultrasonography for follow-up of these patients by comparing the method with angiotomography.Materials and methodsWe conducted a prospective study from June 2012 to May 2013. We examined patients followed-up at the endovascular surgery clinic run by the University Hospital of Londrina after endovascular repair of abdominal aortic aneurysms. All patients underwent angiotomography for follow-up and were also examined using simple abdominal X-rays and vascular ultrasonography.ResultsA total of 30 patients were analyzed, with a mean age of 73 years and a mean aneurysm diameter of 6 cm. Four endoleaks were detected. Vascular ultrasonography achieved sensitivity of 75% and specificity of 96% for classification of these endoleaks, in comparison with angiotomography.ConclusionsVascular ultrasonography is an excellent primary method for evaluation and post-surgical follow-up of patients treated with endovascular repair of abdominal aorta aneurysms. However, when ultrasonography detects problems or is difficult to accomplish, it should be supplemented with a more specific investigation for diagnostic confirmation.

Influencing Factors for Abdominal Aortic Aneurysm Sac Shrinkage and Enlargement after EVAR: Clinical Reviews before Introduction of Preoperative Coil Embolization

BACKGROUND

We previously reported effectiveness of coil embolization (CE) to aortic branched vessels before endovascular aortic repair (EVAR) for abdominal aortic aneurysm (AAA) because of significant shrinkage of aneurysmal sac. In this study, we investigated EVAR cases to clarify influential factors of aneurysmal shrinkage and enlargement.

METHODS

148 consecutive cases before the introduction of CE were retrospectively reviewed based on the presence of PT2EL (persistent type 2 endoleak) and change in sac diameter after EVAR by multivariate analysis.

RESULTS

(A) PT2EL risk factors were patent inferior mesenteric artery (IMA) and thinner mural thrombus inside aneurysmal sac. (B) Sac enlargement risk factors were antiplatelet intake, PT2EL, and female gender. (C) Sac shrinkage predictive factors were the absences of thoracic aortic aneurysm, antiplatelet intake, PT2EL, and coronary artery disease.

CONCLUSION

CE to IMA was considered to be effective because patent IMA and antiplatelet intake were significant risk factors for sac enlargement. So, more meticulous therapeutic strategy, including treatment priority (AAA first or CAD first) and choice of treatment (EVAR vs. AAA) based on anatomical features of AAA was required to improve late outcomes.

CT Findings of Risk Factors for Persistent Type II Endoleak from Inferior Mesenteric Artery to Determine Indicators of Preoperative IMA Embolization

PURPOSE

To identify the computed tomography (CT) findings of persistent type II endoleak from the inferior mesenteric artery (IMA) which indicate the need for preoperative IMA embolization.

MATERIALS AND METHODS

Included were 120 patients (96 males, 49-93 years old, mean: 77.7) who underwent endovascular aortic aneurysm repair (EVAR) between June 2007 and October 2010. The relationship between persistent type II endoleak and CT findings of IMA orifice was examined.

RESULTS

CT showed no type II endoleak from IMA in 106 patients (89%; Group N), and transient type II endoleak from IMA in 10 patients (8.3%; Group T). CT showed persistent type II endoleak from IMA in 4 patients (3.3%; Group P) and three of them underwent reintervention. Univariate Cox-Mantel test analysis indicated that stenosis (p = 0.0003) and thrombus (p = 0.043) in IMA orifice were significant factors for persistent type II endoleak. The ratios of patients with proximal IMA more than 2.5 mm diameter in Groups N, Y, and P were 26/106 (24%), 5/10 (50%) and 4/4 (100%), respectively.

CONCLUSION

Indicators for embolization of IMA prior to EVAR for the prevention of type II endoleak appear to be: (1) more than 2.5 mm in diameter and (2) no stenosis due to calcification or mural thrombus in IMA orifice.

Open Reintervention for Aneurysmal Sac Enlargement after EVAR

We performed a late open reintervention for aneurysmal sac enlargement due to persistent type 2 endoleak (PT2EL) after EVAR for 8 of 286 patients. Surgical techniques are as follows: (1) The entire aneurysmal body was exposed. (2) All the aortic branched vessels were ligated. (3) The aneurysmal sac was opened followed by the performance of complete hemostasis. (4) An equine pericardium was wrapped and sutured to the aneurysmal sac to for reinforcement. This method is considered to be one of the feasible options for the treatment of aneurysmal sac re-enlargement after EVAR.

Elective endovascular aortic repair conversion for type Ia endoleak is not associated with increased morbidity or mortality compared with primary juxtarenal aneurysm repair

OBJECTIVE

Type Ia endoleak after endovascular aortic repair (EVAR) can be a challenging complication to manage, and due to concerns regarding morbidity and mortality of open surgical conversion (OSC), reports of complex endoluminal salvage techniques are increasing. Despite development of these endovascular remedial strategies, many patients ultimately require OSC. The purpose of this analysis was to outcomes of elective OSC for type Ia endoleak and compare them with elective primary open juxtarenal aneurysm repair (OJAR) to determine if these concerns are warranted.

METHODS

From 2000 to 2012, 54 patients underwent EVAR OSC at median time of 27 months (interquartile range, 9-55 months). Indications included endograft thrombosis in 2 (4%), intraoperative EVAR failure in 3 (6%), rupture in 5 (9%), graft infection in 6 (11%), and type Ia endoleak in 25 (all: 38 [70%]). Because many OSCs are performed for emergency indications without endovascular options, we chose elective type Ia endoleak patients as our study group. These 25 patients were compared with an elective OJAR cohort matched by anatomy and comorbidities. Primary end points were 30-day and 1-year mortality. Secondary end points included early complications, cross-clamp time, procedure time, blood loss, and length of stay.

RESULTS

Demographic and comorbidity data in the OSC and OJAR groups did not differ, with the exception that OJAR patients presented with smaller aneurysm diameter and a higher rate of chronic obstructive pulmonary disease (P = .03). OSC patients more frequently underwent a nontube graft repair (OSC, n = 20 [80%] vs OJAR, n = 6 [24%]; P = .0002), required longer procedure times (P = .03), and received more plasma transfusions (P = .03). The 30-day mortality was 4% in both groups (observed difference in rates, 0%; 95% confidence interval for difference in mortality rates, -14.0% to 14.0%; P = 1). A similar rate of major complications occurred (OSC, n = 9 [36%] vs OJAR, n = 8 [32%]; P = 1). One-year survival was 83% in OSC and 91% in OJAR (observed difference, 7%; 95% confidence interval, -15% to 29%; P = .65).

CONCLUSIONS

Despite many advances in EVAR technology, the need for OSC persists and will likely become more common as older-generation devices fail or providers attempt EVAR in more anatomically complex patients. Elective OSC for type Ia endoleak can be technically challenging but is not associated with increased morbidity or mortality compared with OJAR in appropriately selected patients. These results should be considered before pursuing complex endovascular remediation of EVAR failures.

Abdominal aortic aneurysm repair: long-term follow-up of endovascular versus open repair

INTRODUCTION

To compare early and long-term outcomes of endovascular abdominal aortic aneurysm repair (EVAR) versus open repair (OPEN).

DESIGN

Prospective observational, per protocol, non-randomized, with retrospective analyses.

MATERIAL AND METHODS

Between 2000 and 2005, a total of 311 patients having EVAR or OPEN repair of infrarenal abdominal aortic aneurysms were identified and included in this prospective single-center observational study. A propensity score-based optimal-matching algorithm was employed, and 138 patients undergoing EVAR procedures were matched (1: 1) to OPEN repair.

RESULTS

Open repair showed higher hospital mortality (17% vs. 6%, p = 0.004), respiratory failure (p < 0.026), transfusion requirement (p < 0.001), and intensive care unit admission (27% vs. 7%, p < 0.001), and longer hospitalization (p < 0.001). Median follow-up was 70 months (25(th) to 75(th) percentile, 24 to 101). Actuarial survival estimates at 1, 5 and 10 years were 93%, 74%, 49% for the OPEN group compared to 89%, 69%, 59% for the EVAR group (p = 0.465). A significant difference between groups was observed in younger patients (< 75 years) only (p < 0.044). Late complication and re-intervention rates were significantly higher in EVAR patients (p < 0.001 and p = 0.002, respectively). Freedom from late complications at 1, 5 and 10 years was 96%, 92%, 86%, and 84%, 70%, 64% for OPEN and EVAR procedures, respectively.

CONCLUSIONS

Our experience confirms the excellent results of the EVAR procedures, offering excellent early and long-term results in terms of safety and reduction of mortality. Patients < 75 years seem to benefit from EVAR not only in the immediate postoperative period but even in a long-term perspective.