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We performed a contemporary assessment of clinical and radiographic factors of stroke after thoracic endovascular aortic repair (TEVAR). Patients undergoing TEVAR from 2006 to 2017 were identified. We assessed clinical and radiographic data, including preoperative head and neck computed tomography, Doppler ultrasonography, and intraoperative angiography. Our primary outcome was stroke after TEVAR. Four hundred seventy-nine patients underwent TEVAR, mean age 68.1 ± 19.5 years, 52.6% male. Indications for TEVAR included aneurysms (n = 238, 49.7%) or dissections (n = 152, 31.7%). Ishimaru landing zones were Zone 2 (n = 225, 47.0%), Zone 3 (n = 151, 31.5%), or Zone 4 (n = 103, 21.5%). Stroke occurred in 3.8% (n = 18) of patients, with 1.9% (8) major events (modified Rankin Scale >3). Pathophysiology was predominantly embolic (n = 14), and occurred in posterior (n = 6), anterior (n = 6), or combined circulation (n = 4), and in the left hemisphere (n = 10) or bilateral (n = 6). Univariate analysis suggested use of lumbar drain (33.3% versus 57.2%, P = 0.04), inability to revascularize the left subclavian artery (16.7% vs 5.2%, P = 0.04) and number of implanted components (2.5 ± 1.2 vs 2.0 ± 0.97, P = 0.03) were associated with stroke. Multivariable analysis identified number of implanted components (OR 1.7, 95%CI 1.17-2.67 P = 0.00) and inability to revascularize the left subclavian artery as independent predictors of stroke. Stroke was associated with a higher perioperative mortality (27.8% vs 3.9%, P < 0.01). Stroke after TEVAR is primarily embolic in nature and related to both anatomic and procedural factors. This may have important implications for device development in the era of endovascular arch repair., (Copyright © 2022. Published by Elsevier Inc.)

Background: Infected abdominal aortic and/or iliac aneurysm (AAIA) is a rare condition with a high mortality rate when treated with open surgery. In the past decade, the condition has increasingly been treated with endovascular aneurysm repair (EVAR). However, early and late outcomes, including the continued need for antibiotic treatments and predictors of persistent infection, are poorly understood., Methods: We evaluated the outcomes of patients who underwent EVAR for infected AAIA from January 2010 to October 2017. We collected data including patient age, gender, clinical presentation, aneurysm location, culture results, intraoperative details, postoperative complications, 30-day mortality, in-hospital mortality, persistent infection, reintervention, and survival., Results: Among 792 patients diagnosed with AAIA, 64 were diagnosed with primary infected aneurysm, underwent EVAR, and were included in this study (81.3% male; median age, 72 years; range, 18-94 years). The most commonly isolated organisms were Salmonella species (34%), followed by Streptococcus (21%), and Staphylococcus species (21%). Aneurysms were intact in 48 patients (75%) and were ruptured in 16 (25%). The perioperative mortality was 4.7% (3 patients) of whom one was diagnosed with ruptured infected AAIA. Six (9.4%) patients died during hospitalization, 5 of severe sepsis with multiorgan failure and one of myocardial infarction. Among the 58 surviving patients, 34 (58.6%) had persistent infection, of whom 13 (22.4%) required early and late reintervention, including 2 with endograft infection, 8 with primary and secondary aortoenteric fistula, 2 with recurrent new aortic infection, and one with graft limb occlusion. The remaining 24 patients were able to discontinue antibiotics and had no recurrence or need for reintervention. Overall survival rates at 1, 3, and 5 years in the antibiotic-discontinuation group were 91.7%, 87.5%, and 68.0%, respectively, and 82.4%, 52.6%, and 32.9%, respectively, in the persistent-infection group (P = 0.009). In multivariable analysis, primary aortoenteric fistula (Adjusted OR [aOR], 20.469; 95% confidence interval (CI), 1.265-331.320; P = 0.034) and preoperative serum albumin level <3 g/dL (aOR, 7.399; 95% CI, 1.176-46.558; P = 0.033) were preoperative parameter that predicted persistent infection. A C-reactive protein level more than 5 mg/L (aOR, 34.378; 95% CI, 4.888-241.788; P < 0.001) was observed in patients with persistent infection., Conclusions: EVAR is a feasible treatment with acceptable perioperative mortality for infected AAIA. Patients able to discontinue antibiotics have better survival and lower reintervention rates than those with persistent infection. A preoperative albumin level below 3 g/dL and primary aortoenteric fistula predicted persistent infection in this population., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: To provide an overview of the literature on the mid-term outcomes of chimney EVAR (ChEVAR) for the treatment of juxtarenal abdominal aortic aneurysms (JAAA)., Methods: Different electronic databases were searched for published articles up to January 2020. The eligibility criteria were studies describing mid- or long-term outcomes of chimney EVAR (mean follow-up at least 1 year) for treatment of JAAA, including more than 10 cases, published in English, and with full text available. The outcomes measure were overall survival rate, target vessel patency, and freedom from reintervention at 3 years. Quality of the included studies was analyzed using the MINORS criteria. Pooled effect estimates were analyzed using random-effect models and heterogeneity was tested using I 2 statistics., Results: Thirteen articles met the inclusion criteria. The included studies described 1,019 patients. According to the quality assessment, methodological quality was moderate to poor. The pooled overall survival, freedom from reintervention, and target vessel patency at 3 year was 81.4 % (95%CI 73.8-87.9), 85.7% (95%CI 75.6-93.5), and 95.1% (95%CI 89.3-98.7) respectively., Conclusions: The results of this review show good to acceptable short and mid-term survival and good mid-term durability, which supports that ChEVAR as a suitable alternative in high-risk JAAA. However, proper patient selection for ChEVAR seems essential to attain good mid-term outcomes, and further large prospective and good quality studies are required to demonstrate its long-term results and enable conclusions on specific determinants for outcome., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Objective: To study the mid- and long-term outcomes of type II endoleak treatment after EVAR and the technical aspects of different techniques to exclude endoleaks which different embolic agents., Methods: A systematic review was performed using the approach recommended by the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for meta-analyses of interventional studies. The comprehensive search was conducted using the following database: MEDLINE, EMBASE, and the Cochrane Library. Patient characteristic, intervention approaches, embolic agents, and results at mid and long term follow up were studied., Results: A total of 6 studies corresponding to a total of 141 patients fulfilled the inclusion criteria with a mean age of 73-78.6 years and a mean duration of follow up varying from 25 to 42 months. There were different techniques for embolization used (translumbar, transarterial, and transcaval approach) with various types of embolic agents. In all studies, the indication for embolization of the type II endoleaks was sac enlargement of more than 5 mm. A wide range of technical success rate was reported regardless of the intervention strategy being used (17,6%-100%). The overall technical success rate of all studies was 62%., Conclusion: This systematic review shows that there is a wide variety of techniques to exclude a persistent type II endoleak. Different kinds of embolic agents have be used. Due to a lack of peer reviewed data on longterm follow-up, it was not possible to come to recommendations what treatment would be the best for a durable exclusion of a persistent type II endoleak after an initially successful EVAR. There remains an urgent need for proper executed studies, either randomized or with close observation in relation to longer follow-up., (Copyright © 2021. Published by Elsevier Ltd.)

Objectives: Confident growth assessment during imaging follow-up is often limited by substantial variability of diameter measurements and the fact that growth does not always occur at standard measurement locations. There is a need for imaging-based techniques to more accurately assess growth. In this study, we investigated the feasibility of a three-dimensional aortic growth assessment technique to quantify aortic growth in patients following open aortic repair., Methods: Three-dimensional aortic growth was measured using vascular deformation mapping (VDM), a technique which quantifies the localized rate of volumetric growth at the aortic wall, expressed in units of Jacobian (J) per year. We included 16 patients and analysed 6 aortic segments per patient (96 total segments). Growth was assessed by 3 metrics: clinically reported diameters, Jacobian determinant and targeted diameter re-measurements., Results: VDM was able to clearly depict the presence or absence of localized aortic growth and allows for an assessment of the distribution of growth and its relation to anatomic landmarks (e.g. anastomoses, branch arteries). Targeted diameter change showed a stronger and significant correlation with J (r = 0.20, P = 0.047) compared to clinical diameter change (r = 0.15, P = 0.141). Among 20/96 (21%) segments with growth identified by VDM, growth was confirmed by clinical measurements in 7 and targeted re-measurements in 11. Agreement of growth assessments between VDM and diameter measurements was slightly higher for targeted re-measurements (kappa = 0.38) compared to clinical measurements (kappa = 0.25)., Conclusions: Aortic growth is often uncertain and underappreciated when assessed via standard diameter measurements. Three-dimensional growth assessment with VDM offers a more comprehensive assessment of growth, allows for targeted diameter measurements and could be an additional tool to determine which post-surgical patients at high and low risk for future complications., (© The Author(s) 2021. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Objectives: Differential luminal enhancement [between true lumen (TL) and false lumen (FL)] results from differential flow patterns, most likely due to outflow restriction in the FL. We aimed to assess the impact of differential luminal enhancement at baseline computed tomography angiography on the risk of adverse events in patients with acute type B aortic dissection (TBAD)., Methods: Baseline computed tomography angiographies of patients with acute TBAD between 2007 and 2016 (n = 48) were analysed using three-dimensional software at multiple sites along the descending thoraco-abdominal aorta. At each location, we measured contrast density in TL and FL [Houndsfield unit (HU)], maximal diameter (cm) and circumferential FL extent (°). Outcome data were collected via retrospective chart review. Multivariable logistic regression models were employed to determine the independent risk of TL-FL differential luminal enhancement on aneurysm formation (maximal diameter ≥55 mm) and medical treatment failure., Results: Patients were predominately male (75%) and 52.8±12.9 years at diagnosis. The mean follow-up was 5.9±2.6 years, and 42% (n = 20/48) patients were diagnosed with thoraco-abdominal aortic aneurysm. The baseline absolute difference between FL and TL contrast density measured at 2 cm distal to primary entry tear (TL-FLabs-Tear) was significantly higher among patients who developed aneurysm (26 HU, IQR: 15-53 vs 13 HU, IQR: 4-24, P = 0.001). Aneurysm development during follow-up was predicted by TL-FLabs-Tear (odds ratio 1.07, P = 0.012) and baseline maximal aortic diameter (odds ratio 1.90, P < 0.001). High (≥18 HU) differential luminal enhancement was associated with lower rates of aneurysm-free survival and higher rates of medical treatment failure., Conclusions: Differential luminal enhancement may be a novel predictor of aneurysm formation among patients with acute TBAD., (© The Author(s) 2021. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Introduction: While the operator radiation dose rates are correlated to patient radiation dose rates, discrepancies may exist in the effect size of each individual radiation dose predictors. An operator dose rate prediction model was developed, compared with the patient dose rate prediction model, and converted to an instant operator risk chart., Materials and Methods: The radiation dose rates (DR operator for the operator and DR patient for the patient) from 12,865 abdomen X-ray acquisitions were selected from 50 unique patients undergoing standard or complex endovascular aortic repair (EVAR) in the hybrid operating room with a fixed C-arm. The radiation dose rates were analyzed using a log-linear multivariable mixed model (with the patient as the random effect) and incorporated varying (patient and C-arm) radiation dose predictors combined with the vascular access site. The operator dose rate models were used to predict the expected radiation exposure duration until an operator may be at risk to reach the 20 mSv year dose limit. The dose rate prediction models were translated into an instant operator radiation risk chart., Results: In the multivariate patient and operator fluoroscopy dose rate models, lower DR operator than DR patient effect size was found for radiation protocol (2.06 for patient vs 1.4 for operator changing from low to medium protocol) and C-arm angulation. Comparable effect sizes for both DR operator and DR patient were found for body mass index (1.25 for patient and 1.27 for the operator) and irradiated field. A higher effect size for the DR operator than DR patient was found for C-arm rotation (1.24 for the patient vs 1.69 for the operator) and exchanging from femoral access site to brachial access (1.05 for patient vs 2.5 for the operator). Operators may reach their yearly 20 mSv year dose limit after 941 minutes from the femoral access vs 358 minutes of digital subtraction angiography radiation from the brachial access., Conclusion: The operator dose rates were correlated to patient dose rate; however, C-arm angulation and changing from femoral to brachial vascular access site may disproportionally increase the operator radiation risk compared with the patient radiation risk. An instant risk chart may improve operator dose awareness during EVAR.

Purpose: Up to 10% of acute type A aortic dissection (TAAD) patients are deemed unfit for open surgical repair, exposing these patients to high mortality rates. In recent years, thoracic endovascular aortic repair has proven to be a promising alternative treatment modality in specific cases. This study presents a comprehensive overview of the current state of catheter-based interventions in the setting of primary TAAD., Methods: A literature search was conducted, using MEDLINE and PubMed databases according to PRISMA guidelines, updated until January 2020. Articles were selected if they reported on the endovascular repair of DeBakey Type I and II aortic dissections. The exclusion criteria were retrograde type A dissection, hybrid procedures, and combined outcome reporting of mixed aortic pathologies (e.g., pseudoaneurysm and intramural hematoma)., Results: A total of 31 articles, out of which 19 were case reports and 12 case series, describing a total of 92 patients, were included. The median follow-up was 6 months for case reports and the average follow-up was 14 months for case series. Overall technical success was 95.6% and 30-day mortality of 9%. Stroke and early endoleak rates were 6% and 18%, respectively. Reintervention was required in 14 patients (15%)., Conclusion: This review not only demonstrates that endovascular repair in the setting of isolated TAAD is feasible with acceptable outcomes at short-term follow-up, but also underlines a lack of mid-late outcomes and reporting consistency. Studies with longer follow-up and careful consideration of patient selection are required before endovascular interventions can be widely introduced., (© 2020 Wiley Periodicals LLC.)

Background: Abdominal aortic aneurysm with severe infrarenal neck angle (>60°) has long been thought to be an obstacle to endovascular aneurysm repair. However, some previous studies reported endovascular aneurysm repair to be safe and efficacious for treating abdominal aortic aneurysm in patients with severe neck angulation. The aim of this study was to investigate the early and late outcomes of endovascular aneurysm repair to treat abdominal aortic aneurysm compared between patients with severe and non-severe infrarenal neck angulation., Methods: Fifty-four severe and 144 non-severe neck angulation patients who were treated at Siriraj Hospital (Bangkok, Thailand) during January 2010-October 2013 were recruited. The primary endpoints were intraoperative neck complications (e.g., type 1A endoleak or proximal graft migration) and immediate adjunct aortic neck procedures. The secondary endpoints included perioperative mortality, overall survival, and the proportion of patients that were reintervention-free at five years compared between the severe and non-severe groups., Results: Severe angulation patients were significantly older than non-severe angulation patients (77 ± 6.3 vs. 74 ± 7.9 years; p  =   0.021). The median proximal angle was significantly greater in the severe group (82° vs. 13.5°; p  <   0.001). Intraoperative proximal neck complications developed in 29.6% of patients in the severe angulation group compared with 9.0% in the non-severe group ( p  <   0.001). Significantly more patients in the severe group required intraoperative adjunct procedures (29.6% vs. 7.6%; p  <   0.001). There was no significant difference in perioperative mortality between groups. At the five-year follow-up, there was no significant difference between groups for overall survival or the proportion of patients that remained reintervention-free., Conclusions: Endovascular aneurysm repair to treat abdominal aortic aneurysm in patients with severe proximal neck angulation is technically feasible and safe Although the severe angulation group had a higher rate of intraoperative neck complications and immediate adjunct neck procedures than the non-severe group, there was no significant difference between groups for 30-day mortality, overall survival or the proportion of patients who remained reintervention-free at five years.

Objective: As elastin fibres in the aorta deteriorate with age, the descending thoracic aorta (DTA) becomes longer and more tortuous. In patients with DTA aneurysms, this increased tortuosity may result in a hostile haemodynamic environment for thoracic endovascular aortic repair (TEVAR). The objective of this study was to analyse how increased tortuosity affects haemodynamic displacement forces (DFs) in different segments of the DTA in patients with DTA aneurysms (DTAAs)., Methods: Thirty patients with DTAAs were selected to form three equal groups based on the maximum tortuosity of their DTA: low < 30°, moderate 30°-60°, and high > 60°. Computational fluid dynamics simulations were performed to calculate DFs in all patients. Image based segmentations were carried out to create patient specific models of the aortic geometry. When physiological simulation results were obtained, the haemodynamic DFs on the aortic wall were calculated in four segments of the DTA (zones 4A - D). To enable comparison of DFs in different segments, the DF was normalised by the aortic wall surface area, the equivalent surface traction (EST)., Results: The mean age was 73 years, with 67% male. In zone 4C, where most tortuosity occurs, the EST in patients with high tortuosity was more than three times higher, than those with low tortuosity (low, 743 N/m 2 ; moderate, 956 N/m 2 ; high, 2294 N/m 2 ; p = .004). These differences could be attributed to the higher sideways components of the DF vectors, which were more than two times greater in patients with high tortuosity than in patients with low or moderate tortuosity (low, 5.01 N; moderate, 5.50 N; high, 13.21 N; p = .009)., Conclusion: High tortuosity results in increased displacement forces in the distal segments of the DTA. These forces should be taken into account when planning for TEVAR, as potentially they increase the risk of stent graft related complications, such as migration and endoleak., (Copyright © 2019 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.)

Background: Complications after thoracic endovascular aortic repair (TEVAR) are common. Even after a successful TEVAR, a late endoleak (>30 days) can occur. The objective of this study is to summarize the current evidence and, if lacking, the need of evidence regarding the incidence and predictive factors for type 1b endoleak in patients with aortic aneurysm treated with TEVAR., Methods: A systematic review of the literature was performed on endoleak type 1b, in patients with aortic aneurysm, after TEVAR. The PubMed and Embase databases were systematically searched for articles regarding endoleak type 1b up to January 2019. The main subjects discussed are the incidence, risk factors, treatment, and prognosis., Results: About 722 articles were screened, and 16 articles were included in this review. The reported incidence of endoleak is between 1.0% and 15.0%, with a mean follow-up duration of at least 1 year. Type 1b endoleak is associated with an increased aortic tortuosity index (>0.15 cm -1 ). No significant difference is found in relation to age and gender. Treatment is required in most cases (22/27) and is usually performed with distal extension of the stent graft (21/27). There are no data regarding stent graft oversizing, length of distal landing zone, and differences between devices or the prognosis for patients with type 1b endoleak., Conclusions: Limited literature is available on the occurrence of type 1b endoleak after TEVAR. A tortuous aorta can be associated as a predictive factor for the occurrence of type 1b endoleak. Data clearly delineating the anatomic variables predicting type 1b endoleak should be examined and listed. Likewise, the impact of more recent conformable devices to prevent complications like type 1b endoleaks from occurring should be elucidated., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objectives: Current endografts for thoracic endovascular aortic repair (TEVAR) are much stiffer than the aorta and have been shown to induce acute stiffening. In this study, we aimed to estimate the impact of TEVAR on left ventricular (LV) stroke work (SW) and mass using a non-invasive image-based workflow., Methods: The University of Michigan database was searched for patients treated with TEVAR for descending aortic pathologies (2013-2016). Patients with available pre-TEVAR and post-TEVAR computed tomography angiography and echocardiography data were selected. LV SW was estimated via patient-specific fluid-structure interaction analyses. LV remodelling was quantified through morphological measurements using echocardiography and electrocardiographic-gated computed tomography angiography data., Results: Eight subjects were included in this study, the mean age of the patients was 68 (73, 25) years, and 6 patients were women. All patients were prescribed antihypertensive drugs following TEVAR. The fluid-structure interaction simulations computed a 26% increase in LV SW post-TEVAR [0.94 (0.89, 0.34) J to 1.18 (1.11, 0.65) J, P = 0.012]. Morphological measurements revealed an increase in the LV mass index post-TEVAR of +26% in echocardiography [72 (73, 17)  g/m2 to 91 (87, 26)  g/m2, P = 0.017] and +15% in computed tomography angiography [52 (46, 29)  g/m2 to 60 (57, 22)  g/m2, P = 0.043]. The post- to pre-TEVAR LV mass index ratio was positively correlated with the post- to pre-TEVAR ratios of SW and the mean blood pressure (ρ = 0.690, P = 0.058 and ρ = 0.786, P = 0.021, respectively)., Conclusions: TEVAR was associated with increased LV SW and mass during follow-up. Medical device manufacturers should develop more compliant devices to reduce the stiffness mismatch with the aorta. Additionally, intensive antihypertensive management is needed to control blood pressure post-TEVAR., (© The Author(s) 2018. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Background: The well-established, gold standard treatment for juxtarenal abdominal aortic aneurysms (JAAAs) is open repair (OR). However, endovascular treatment with fenestrated or chimney grafts has been increasingly performed in the past decade. This study compared the outcomes of OR with 2 endovascular methods in JAAA., Methods: We retrospectively reviewed consecutive patients with JAAA who underwent OR (n = 32), repair with fenestrated stent grafts (fenestrated endovascular aortic aneurysm repair [FEVAR], n = 20), or chimney grafts (Ch-EVAR, n = 23) during the period from January 2011 to December 2016 at a single center. Our primary end point was perioperative mortality. Secondary end points included renal function impairment, new-onset dialysis, procedural details, and postoperative complications. Kaplan-Meier analysis was used to estimate freedom from late reintervention, primary patency of target vessel stent grafts, and overall survival., Results: There were no significant differences between groups in baseline characteristics. Perioperative mortality was similar in all the 3 groups (3.1% (1/32) in the OR group, 0% in the FEVAR group, and 4.3% (1/23) in the Ch-EVAR group. Mean follow-up duration was 36.7 months (range 1-75 months). There were no significant differences between groups regarding any of the secondary end points, except for blood loss (which was significantly greatest in the OR group), and there was no significant difference in overall survival. Estimated target vessel stent patency at 1 and 4 years was 93.8% and 93.8% in the FEVAR group, and 89.5% and 89.5% in the Ch-EVAR group. There was no significant difference between groups in estimated freedom from late reintervention (96.4% in the OR group, 77.2% in the FEVAR group, and 82.3% in the Ch-EVAR group)., Conclusions: Open surgery is an acceptable and effective treatment for JAAA. However, FEVAR and Ch-EVAR also showed high technical success rates and low perioperative mortality, with acceptable reintervention rates during follow-up., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Introduction: Endovascular aortic repair (EVAR) has improved over the last two decades. Approximately 80% of the patients presenting with an abdominal aortic aneurysm (AAA) is nowadays primarily treated with EVAR., Areas Covered: In this review, the differences between endovascular and open repair, the clinical characteristics needed for EVAR, the role of clinical imaging and the developments in EVAR technology will be discussed. Early mortality is lower in EVAR as compared to open repair, whereas this benefit is lost after 3 years postoperatively. EVAR comes with a high reintervention rate, with endoleak being the most important predictive factor for reintervention. Expanding technical possibilities have allowed surgeons to choose from a palate of endovascular approaches in aneurysm patients with challenging anatomies., Expert Commentary: Although EVAR has taken a giant leap forward in development, the new developments have seemed to surpass the long-term limitations with older devices. It is important to start focusing on the current limitations of EVAR, in particular the durability of devices in the human variable anatomic and dynamic environment.

Purpose: To investigate the hypothesis that interventions involving retrograde below-the-knee (BTK) vessel punctures have an acceptably low complication rate and high procedural success., Methods: A systematic review was performed of the MEDLINE and Scopus databases for articles describing the results of BTK retrograde access for peripheral interventions. Outcome measures were access success, procedure success, and complications. A predefined subgroup analysis was performed of prospective studies to reduce the influence of possible reporting bias on outcomes., Results: Nineteen articles, including 3 prospective studies, were selected, including a total of 1905 interventions in 1395 patients (mean age 69.5 years; 918 men). The BTK vessels were punctured in 1168 (61.3%) of these interventions. Access was successful in 94.0% of BTK attempts, 86.0% of all lesions were successfully crossed using a retrograde access, and 84.0% of interventions achieved technical success. Forty-eight (4.1%) distal access site complications were reported. Vessel perforations were seen in 13 (1.1%) interventions, vasospasm in 5 (0.4%), and acute distal occlusions in 5 (0.4%). Predefined subgroup analysis of prospective studies showed similar results (p=0.24)., Conclusion: A retrograde approach to facilitate peripheral endovascular interventions is a safe and successful technique and should be considered when an antegrade approach is not possible or fails to cross the lesion. Because of missing data on long-term outcomes and methodological shortcomings, real world data of retrograde access in nonexpert centers remains necessary before this technique can be advised to all interventionists dealing with peripheral artery disease.

Objective: This study measured the cumulative occupational X-ray radiation dose received by support staff during endovascular aortic procedures and during additional intraoperative steps in the hybrid operating room., Methods: Radiation dose measurements were performed during interventions on 65 patients receiving 90 stent grafts during endovascular aneurysm repair (EVAR), bifurcated EVAR, thoracic EVAR, iliac branched device deployment, aortouni-iliac stenting, and fenestrated/branched EVAR (F/BrEVAR). X-ray imaging was acquired using the Philips Allura FD20 Clarity System (Philips Medical Systems, Best, The Netherlands). The occupational radiation dose (also referred to as the estimated effective dose, E, measured in millisieverts) was measured with the DoseAware Xtend system (Philips Medical Systems) personal dosimeters. E was reported per staff member (E STAFF ), where "staff" was a generic term for each staff member included in the study: the first operator (FO), the second operator (ESO), a virtual maximum operator (MO), and all additional supporting staff, including the sterile nurse, nonsterile nurse, anaesthesiologist, and radiation technician. The primary outcome was the median cumulative E STAFF (or E FO , E MO , and so on), which was presented as the median cumulative dose per intervention and stratified for several within-interventional EVAR and F/BrEVAR steps or stents. The second outcome was the percentage of the absorbed E by a supporting staff member in relation to the E measured by the reference badge attached on the C-arm (E STAFF% or E FO% , E MO% , and so on). All outcomes are presented as median with interquartile range, unless stated differently., Results: The occupational effective dose in millisieverts of the MO (E MO ) was 0.055 (0.029-0.082) for aortouni-iliac stenting (n = 6), 0.084 (0.054-0.141) during thoracic EVAR (n = 14), 0.036 (0.026-0.068) during bifurcated EVAR (n = 38), 0.054 (0.035-0.126) during iliac branched device deployment (n = 8), and 0.345 (0.235-0.757) during F/BrEVAR (n = 24). The median E MO in millisieverts was 0.025 (0.012-0.062) per renal target vessel (TV) and 0.146 (0.07-0.315) for a nonrenal visceral TV. During all noncomplex interventions, the E MO% was 4.4% (2.7%-7.3%), with the lowest median rate at 3.5% (2.5%-5%) for EVAR. The highest median rate E MO% was found for F/BrEVAR procedures: 8.2% (5.0%-14.4%)., Conclusions: With maximum operator shielding during femoral access, relative occupational radiation risk can be minimized. However, digital subtraction angiography image acquisition, recanalization of TVs, recanalization of superior mesenteric artery or celiac artery, and recanalization of branched TVs are predictors for increased occupational radiation dose risks caused by increased radiation doses to the patient and reduced options for shielding of the operator., (Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: To assess whether the Modified Arch Landing Areas Nomenclature (MALAN), which merges Ishimaru's map with the Aortic Arch Classification, predicts the magnitude of displacement forces and their orientation in proximal landing zones for TEVAR., Methods: Computational fluid dynamic (CFD) modelling was employed to prove the hypothesis. Healthy aorta CT angiography scans were selected based on aortic arch geometry to reflect Types I to III arches equally (each n = 5). CFDs were used to compute pulsatile displacement forces along the Ishimaru's landing zones in each aorta including their three dimensional orientation along the upward component and sideways component. Values were normalised to the corresponding aortic wall area to calculate equivalent surface traction (EST)., Results: In Types I and II arches, EST did not change across proximal landing zones (p = .297 and p = .054, respectively), whereas in Type III, EST increased towards more distal landing zones (p = .019). Comparison of EST between adjacent zones, however, showed that EST was greater in 3/II than in 2/II (p = .016), and in 3/III than in 2/III (p = .016). Notably, these differences were related to the upward component, that was four times greater in 3/II compared with 2/II (p < .001), and five times greater in 3/III compared with 2/III (p < .001)., Conclusion: CFD modelling suggests that MALAN improves discrimination of expected displacement forces in proximal landing zones for TEVAR, which might influence clinical outcomes. The clinical relevance of the finding, however, remains to be validated in a dedicated post-operative outcome analysis of patients treated by TEVAR of the arch., (Copyright © 2017 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.)

Objective: The beneficial effect of renin-angiotensin system (RAS) inhibitors has been well-established in patients with cardiovascular disease; however, their effectiveness in patients with chronic limb-threatening ischemia (CLTI), a selected disease-burdened population, is largely unknown. The purpose of this study was to evaluate long-term outcomes of RAS inhibitor use in patients with CLTI undergoing a vascular intervention., Methods: For this study, all patients with CLTI undergoing a first-time revascularization (bypass or endovascular) were analyzed at our institution between 2005 and 2014. Patients discharged on an RAS inhibitor (angiotensin-converting enzyme inhibitor or angiotensin receptor blocker) were compared with those not on an RAS inhibitor. The inverse probability of treatment weighting with additional regression analyses were used to determine the long-term risk of mortality and major adverse events. A sensitivity analysis was performed to assess the dose-related therapeutic response of RAS inhibitors (low-dose vs high-dose therapy)., Results: Between 2005 and 2014, 1303 limbs from 1161 patients were identified. Of these patients, 52% were discharged on an RAS inhibitor, with 67% discharged on a high-dose therapy and 33% on a low-dose therapy. Patients discharged on an RAS inhibitor suffered more frequently from diabetes, hypertension, and myocardial infarction, whereas those not on an RAS inhibitor had more chronic kidney disease (all P < .05). There was no difference in the proportion of patients presenting with tissue loss. After adjustment for these and other baseline covariates, RAS inhibitor use was associated with less late mortality (hazard ratio [HR], 0.78; 95% confidence interval [CI], 0.65-0.94). Discharge on a high-dose RAS inhibitor was associated with lower mortality (HR, 0.70; 95% CI, 0.57-0.86), whereas a low-dose RAS inhibitor was not associated with less mortality (HR, 0.95; 95% CI, 0.73-1.24) compared with patients not prescribed an RAS inhibitor. This association remained significant when comparing high-dose with low-dose therapy (HR, 0.74; 95% CI, 0.55-0.98). No associations were found between RAS inhibitor use and major adverse limb event (HR, 0.95; 95% CI, 0.73-1.22), major amputation (HR, 0.82; 95% CI, 0.57-1.18), or reintervention (HR, 1.05; 95% CI, 0.85-1.31). These point estimates were not different for those on angiotensin-converting enzyme inhibitors vs angiotensin receptor blockers, nor were they affected by the type of revascularization., Conclusions: Patients with CLTI prescribed an RAS inhibitor at discharge demonstrated significantly less long-term mortality, whereas limb events were unaffected. These data indicate that, in these heavily burdened patients, the benefit is restricted to those on a high dose, which underscores the importance of attaining these doses., (Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: The optimal initial revascularization strategy remains uncertain for patients with peripheral arterial disease. The purpose of this study was to evaluate current nationwide selection and perioperative outcomes of patients undergoing bypass or endovascular intervention for infrainguinal disease in those with no prior ipsilateral revascularization., Methods: Patients undergoing nonemergent first-time infrainguinal revascularization were identified in the Targeted Vascular module of the National Surgical Quality Improvement Program (NSQIP) for 2011 to 2014 and stratified by symptom status (chronic limb-threatening ischemia [CLTI] or claudication). Patients treated with endovascular intervention were compared with those who underwent bypass. Multivariable logistic regression was used to evaluate current selection of patients and to establish independent associations between first-time procedures and postoperative outcomes., Results: Of 5998 first-time infrainguinal revascularizations performed, 3193 were bypass procedures (63% for CLTI) and 2805 were endovascular interventions (64% for CLTI). Current patient characteristics associated with an endovascular-first approach as opposed to bypass-first in CLTI patients were age ≥80 years, tissue loss, nonsmoking, functional dependence, diabetes, dialysis, and tibial lesions, whereas age ≥80 years, nonwhite race, nonsmoking, diabetes, and tibial lesions were associated with an endovascular approach for claudication. In comparing first-time endovascular intervention with bypass, there was no difference in 30-day mortality in CLTI patients (univariate: 2.1% vs 2.2%; adjusted: odds ratio [OR], 0.7; 95% confidence interval [CI], 0.4-1.1) or claudication patients (0.3% vs 0.6%). Among CLTI patients, endovascular-first intervention was associated with lower rates of major adverse cardiovascular event (3.6% vs 4.7%; OR, 0.6; 95% CI, 0.4-0.9), surgical site infection (0.9% vs 7.7%; OR, 0.1; 95% CI, 0.1-0.2), bleeding (8.5% vs 17%; OR, 0.4; 95% CI, 0.3-0.5), unplanned reoperation (13% vs 17%; OR, 0.7; 95% CI, 0.5-0.8), and unplanned readmission (17% vs 18%; OR, 0.8; 95% CI, 0.7-0.9). Patients with claudication undergoing endovascular-first intervention also had lower rates of major adverse cardiovascular event (0.8% vs 1.6%; OR, 0.4; 95% CI, 0.2-0.95), surgical site infection (0.7% vs 6.6%; OR, 0.1; 95% CI, 0.04-0.2), bleeding (2.3% vs 6.0%; OR, 0.3; 95% CI, 0.2-0.5), unplanned reoperation (4.3% vs 6.6%; OR, 0.6; 95% CI, 0.4-0.9), and unplanned readmission (5.9% vs 9.0%; OR, 0.6; 95% CI, 0.4-0.8). Conversely, endovascular-first intervention was associated with a higher rate of secondary revascularizations within 30 days for CLTI (4.3% vs 3.1%; OR, 1.6; 95% CI, 1.04-2.3) but not for claudication (2.6% vs 1.9%; OR, 1.7; 95% CI, 0.9-3.4)., Conclusions: An endovascular-first approach as a revascularization strategy for infrainguinal disease was associated with substantially lower early morbidity but not mortality, at the cost of higher rates of postoperative secondary revascularizations. As a national representation of first-time revascularizations, this study highlights the early endovascular perioperative benefit, although more robust long-term data are needed to adopt either one strategy or the other in select patients with peripheral arterial disease., (Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: The objective of this study was to describe our experience with endovascular aneurysm repair (EVAR) with the use of chimney grafts for branch vessel preservation., Methods: Patients treated with a chimney graft procedure between October 2009 and May 2015 were included for analysis. Patients who were not considered eligible for open surgical repair or for conventional, branched, or fenestrated endovascular repair were selected. A standardized operating procedure with left brachial or axillary artery cutdown access for the chimney grafts and bilateral femoral artery cutdown access for the aortic main device was used. Outcomes were noted according to the Society for Vascular Surgery reporting standards. In addition, evolution of gutter area over time was determined. Estimated rates of survival, freedom from aneurysm growth, and clinical success at 24 months of follow-up were calculated., Results: Thirty-three patients (mean age, 77.6 ± 6.8 years; 87.9% male) with a mean preoperative maximum aneurysm diameter of 71.7 ± 13.5 mm were included. A total of 54 of an intended 54 chimney grafts were deployed. Primary technical success and 30-day secondary clinical success rates were 87.9% and 84.8%, respectively. The early mortality rate was 6.1% (n = 2). The early type IA endoleak rate was 6.1% (n = 2), and the chimney graft occlusion rate was 6.1% (n = 2). Median follow-up duration was 26 months (interquartile range, 14.8-37.3 months). The estimated 2-year actuarial survival rate was 78.1% (standard error, ±7.4%). Late complications included type IA endoleak (n = 1), chimney graft occlusion (n = 2), type II endoleak with aneurysm growth (n = 4), and distal stent graft limb kinking and occlusion (n = 1). Late reinterventions included coil or glue embolization (n = 3), distal limb extension (n = 2), open endoleak ligation (n = 2), Palmaz stent placement (n = 1), repeated EVAR (n = 1), and femorofemoral bypass graft (n = 1). At 2 years, the estimated secondary clinical success and freedom from aneurysm growth rates were 80.5% (±7.2%) and 84.4% (±7.2%). Gutter size showed a small but significant decrease over time at the level of the proximal markers and at 10 mm distal from the markers., Conclusions: Midterm results show that a standardized procedure for EVAR using chimney grafts for branch vessel preservation is an acceptable option for high-risk patients with large, complex aneurysms who are unfit for open repair and who have been excluded from fenestrated EVAR. Gutter size decreases over time, but the rate of branch vessel loss and reinterventions demonstrate that this approach should remain reserved for those who are at truly prohibitive risk for open or fenestrated stent graft repair., (Copyright © 2017. Published by Elsevier Inc.)

Background: The impact of left subclavian artery (LSA) revascularization before thoracic endovascular aortic repair (TEVAR) on cerebrovascular flow is not well described. We studied bilateral vertebral and carotid artery flow characteristics before and after TEVAR to evaluate the hemodynamic effects of LSA revascularization., Methods: Seventy-four patients with mixed etiologies (mean age 70.9 ± 10.5 years) underwent LSA revascularization and TEVAR (2006-2016) and had available preoperative and postoperative carotid duplex study available. Data from patient demographics, procedures, preoperative, and postoperative carotid duplex studies were gathered. Revascularization was by left common carotid artery (LCCA) to LSA bypass (n = 70, 94.6%) or LSA to LCCA transposition (n = 4, 5.4%)., Results: Duplex confirmation of antegrade left vertebral artery (LVA) flow decreased significantly after TEVAR with LSA revascularization (100.0% vs. 77.9%, P < 0.001). Incidence of retrograde LVA flow increased from 0.0% to 8.3% (P = 0.063). Postoperatively, LVA bidirectional flow was observed in 3 patients (4.4%). Flow directions in the right vertebral artery (RVA) did not change significantly. Peak systolic velocity (PSV) in the LVA decreased significantly after TEVAR from 55.1 ± 22.0 cm/s to 35.9 ± 26.3 cm/s (P < 0.001). In contrast, PSV increased in the RVA and the right internal carotid artery (ICA; 52.2 ± 21.7 cm/s to 63.2 ± 23.3 cm/s, P = 0.012 and 95.3 ± 46.8 cm/s to 102.8 ± 42.9 cm/s, P = 0.011). PSV did not change significantly in the left ICA. At mean follow-up of 36.6 ± 26.8 months, primary bypass patency was 100.0%. Postoperatively, one case of temporary spinal cord ischemia was seen (1.4%). Stroke rate was 6.9% (n = 5, 100.0% embolic), all without permanent disabilities. Stroke circulation distribution was 60.0% posterior, 20.0% anterior, and 20.0% mixed. Location of stroke was left sided (n = 2) or in both hemispheres (n = 3). There were no deaths at 30 days. Neurological events during follow-up included 3 new strokes. All-cause mortality rate during follow-up was 12.2% (n = 9)., Conclusions: Adjunctive LSA revascularization in the setting of zone 2 TEVAR coverage is associated with hemodynamic vertebral artery changes. Future studies in larger sample sizes should evaluate whether these novel findings are an important determinant of postoperative neurologic events., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Purpose: To determine the midterm outcomes of internal iliac artery (IIA) coverage by a stent-graft in endovascular aortic aneurysm repair (EVAR) under specific anatomic and technical circumstances., Material and Methods: From January 2003 until January 2014, 57 patients with aortoiliac aneurysms, including 20 with 24 IIA aneurysms (IIAAs), underwent EVAR with IIA coverage. IIAA diameter change or IIA thrombosis, buttock claudication, type II endoleak, and secondary interventions related to the IIA were studied., Results: Twenty-five of the 37 patients without IIAA were embolized prior to stent-graft placement, all unilateral, and in 12, the IAA orifice was only overstented. Buttock claudication occurred in only nine (20%) of the embolization patients (9/49 IIA's) (p = .14), while one IIA-related type II endoleak, occurred in the nonembolization group (p = .16). In patients with IIAA(s), the aneurysm diameter decreased in 16 cases (67%). Buttock claudication occurred in 75% of bilateral, and in 14.6% of unilateral embolizations (p = .046)., Conclusions: Carefully selected patients with aortoiliac aneurysm without IIAA may safely undergo hypogastric artery overstenting without preemptive embolization during EVAR. IIA embolization is associated with buttock claudication and should be avoided if possible. Otherwise, at least one IIA should be preserved.

Background: Aortic stiffness is an independent predictor of cardiovascular mortality. In this study, the effect of thoracic endovascular aortic repair (TEVAR) on aortic stiffness is investigated by measuring aortic pulse wave velocity (PWV) in an ex vivo porcine model., Methods: Fifteen fresh porcine thoracic aortas were connected to a benchtop pulsatile system. Intraluminal pressures were recorded in the ascending aorta and at the celiac trunk using a needle connected to a pressure sensor. The distance between the needles was divided by the time difference between the base of the pressure peaks to calculate aortic PWV at baseline and after stent-graft deployment and distal stent-graft extension., Results: Mean aortic PWV was 5.0 m/s at baseline. PWV increased by 4% after proximal stent-graft deployment (P = 0.09) and by 18% after stent-graft extension (P < 0.001). Pulse pressure in the nonstented ascending aorta increased by 11.0 ± 1.2 mm Hg after proximal stent-graft deployment (P < 0.001) and by 17.3 ± 1.5 mm Hg after stent-graft extension (P < 0.001). The increases in PWV and pulse pressure showed a positive linear correlation with the percentage of stent-graft coverage (P < 0.001 and P < 0.001)., Conclusions: In this experimental setup, aortic stiffness increased after stent-graft deployment, dependent on the percentage of the aorta that was covered by stent graft. These results show that TEVAR leads to significant changes in aortic hemodynamics, which merits evaluation in the clinical setting., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The establishment use of fenestrated and branched devices to treat complex aortic aneurysms as a first-line management option has been previously reported. This article reviews the current literature of the use of fenestrated devices to treat complex abdominal and thoracoabdominal type IV aortic aneurysms as a first-line management option. A literature search was performed. This review particularly focuses on all the aspects of the use and results of fenestrated stent-grafts (SGs) in patients with complex abdominal and type IV thoracoabdominal aortic aneurysms and summarizes the available evidence. The use of fenestrated SGs for complex aortic aneurysm disease has grown enormously the last years. SGs with fenestrations, scallops and occasionally branches have to be customized to each patient's anatomy and precisely deployed in vivo. Bridging covered stents between the main graft and the target vessels eventually exclude the aneurysm preserving blood flow to vital organs. Multiple device morphologies have been used incorporating the visceral arteries in various combinations. High technical success rates and satisfactory perioperative outcomes are described as well as mid- and long-term success and durability including target vessel and branch stent perfusion, data emerging mainly from high volume specialized centers. Percentage of target vessel successfully perfused was reported between 90.5 and 100%. 30-day mortality is reported between 0% and 4.1% while the lowest type 1 or type 3 endoleak rates were 2.5% and 1.3% respectively. Migration rates are kept below 3%. Renal failure was the most frequent complication reported. Advances in SG technology have reduced but not eliminated secondary interventions. Outcomes depend mostly on proximal extension of the disease which increases also the complexity of the repair. High level of expertise and organizational facilities are required for better mid- and long-term outcomes. Fenestrated EVAR (fEVAR) has been shown to be safe and effective in the short and mid-term follow-up. Remaining issues including secondary interventions and the need for follow-up are still within the range of those reported for EVAR. These, continue to plague fEVAR for complex abdominal or type IV thoracoabdominal aortic aneurysms.

Objective: This study assessed whether the additional use of the aortic arch classification in type I, II, and III may complement Ishimaru's aortic arch map and provide valuable information on the geometry and suitability of proximal landing zones for thoracic endovascular aortic repair., Methods: Anonymized thoracic computed tomography scans of healthy aortas were reviewed and stratified according to the aortic arch classification, and 20 of each type of arch were selected. Further processing allowed calculation of angulation and tortuosity of each proximal landing zone. Data were described indicating both proximal landing zone and type of arch (eg, 0/I)., Results: Angulation was severe (>60°) in 2/III and in 3/III. Comparisons among the types of arch showed an increase in proximal landing zones angulation (P < .001) and tortuosity (P = .009) depending on the type of arch. Comparisons within type of arch showed no change in angulation and tortuosity across proximal landing zones within type I arch (P = .349 and P = .409), and increases in angulation and tortuosity toward more distal proximal landing zones within type II (P = .003 and P = .043) and type III (P < .001 in both)., Conclusions: The aortic arch classification is associated with a consistent geometric pattern of the aortic arch map, which identifies specific proximal landing zones with suboptimal angulation for stent graft deployment. Arches II and III also appear to have progressively less favorable anatomy for thoracic endovascular aortic repair compared with arch I., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine which patient and C-arm characteristics are the strongest predictors of intraoperative patient radiation dose rates (DRs) during endovascular aneurysm repair (EVAR) procedures and create a patient risk chart., Methods: A retrospective analysis was performed of 74 EVAR procedures, including 16,889 X-ray runs using fixed C-arm imaging equipment. Four multivariate log-linear mixed models (with patient as a random effect) were constructed. Mean air kerma DR (DR AK , mGy/s) and the mean dose area product DR (DR DAP , mGycm 2 /s) were the outcome variables utilized for fluoroscopy as differentiated from digital subtraction angiography (DSA). These models were used to predict the maximum radiation duration allowed before a 2-Gy skin threshold (for DR AK ) or a 500-Gycm 2 threshold (for DR DAP ) was reached., Results: The strongest predictor of DR AK and DR DAP for fluoroscopy imaging was the radiation protocol, with an increase of 200% when changing from "low" to "medium" and 410% from "low" to "normal." The strongest predictors of DR AK and DR DAP for DSA were C-arm angulation, with an increase of 47% per 30° of angulation, and body mass index (BMI), with an increase of 58% for every 5-point increase in BMI. Based on these models, a patient with a BMI of 30 kg/m 2 , combined with 45° of rotation and a field size of 800 cm 2 in the medium fluoroscopy protocol has a predicted DR AK of 0.39 mGy/s (or 85.5 minutes until the 2-Gy skin threshold is reached). While using comparable settings but switching the acquisition to a DSA with a "2 frames per second" protocol, the predicted DR AK will be 6.6 mGy/s (or 5.0 minutes until the 2-Gy threshold is reached)., Conclusion: X-ray radiation DRs are constantly fluctuating during and between patients based on BMI, the protocols, C-arm position, and the image acquisitions that are used. An instant patient risk chart visualizes these radiation dose fluctuations and provides an overview of the expected duration of X-ray radiation, which can be used to predict when follow-up dose thresholds are reached during abdominal endovascular procedures.

Objective: Although an increasing number of patients with peripheral arterial disease undergo multiple revascularization procedures, the effect of prior interventions on outcomes remains unclear. The purpose of this study was to evaluate perioperative outcomes of bypass surgery in patients with and those without prior ipsilateral treatment., Methods: Patients undergoing nonemergent infrainguinal bypass between 2011 and 2014 were identified in the National Surgical Quality Improvement Program Targeted Vascular module. After stratification by symptom status (chronic limb-threatening ischemia [CLTI] and claudication), patients undergoing primary bypass were compared with those undergoing secondary bypass. Within the secondary bypass group, further analysis compared prior bypass with prior endovascular intervention. Multivariable logistic regression analysis was used to establish the independent association between prior ipsilateral procedure and perioperative outcomes., Results: A total of 7302 patients were identified, of which 4540 (62%) underwent primary bypass (68% for CLTI), 1536 (21%) underwent secondary bypass after a previous bypass (75% for CLTI), and 1226 (17%) underwent secondary bypass after a previous endovascular intervention (72% for CLTI). Prior revascularization on the same ipsilateral arteries was associated with increased 30-day major adverse limb event in patients with CLTI (9.8% vs 7.4%; odds ratio [OR], 1.4 [95% confidence interval (CI), 1.1-1.7]) and claudication (5.2% vs 2.5%; OR, 2.1 [95% CI, 1.3-3.5]). Similarly, secondary bypass was an independent risk factor for 30-day major reintervention (CLTI: OR, 1.4 [95% CI, 1.1-1.8]; claudication: OR, 2.1 [95% CI, 1.3-3.5]), bleeding (CLTI: OR, 1.4 [95% CI, 1.2-1.6]; claudication: OR, 1.7 [95% CI, 1.3-2.4]), and unplanned reoperation (CLTI: OR, 1.2 [95% CI, 1.0-1.4]; claudication: OR, 1.6 [95% CI, 1.1-2.1]), whereas major amputation was increased in CLTI patients only (OR, 1.3 [95% CI, 1.01-1.8]). Postoperative mortality was not significantly different in patients undergoing secondary compared with primary bypass (CLTI: 1.7% vs 2.2% [P = .22]; claudication: 0.4% vs 0.6% [P = .76]). Among secondary bypass patients with CLTI, those with prior bypass had higher 30-day reintervention rates (7.8% vs 4.9%; OR, 1.5 [95% CI, 1.0-2.2]) but fewer wound infections (7.3% vs 12%; OR, 0.6 [95% CI, 0.4-0.8]) compared with patients with prior endovascular intervention., Conclusions: Prior revascularization, in both patients with CLTI and patients with claudication, is associated with worse perioperative outcomes compared with primary bypass. Furthermore, prior endovascular intervention is associated with increased wound infections, whereas those with prior bypass had higher reintervention rates. The increasing prevalence of patients undergoing multiple interventions stresses the importance of the selection of patients for initial treatment and should be factored into subsequent revascularization options in an effort to decrease adverse events., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Purpose: To quantify both pulsatile longitudinal and circumferential aortic strains before and after thoracic endovascular aortic repair (TEVAR), potentially clarifying TEVAR-related complications., Methods: This retrospective study assessed the impact of TEVAR on pulsatile aortic strains through custom developed software and cardiac-gated computed tomography imaging of 8 thoracic aneurysm patients (mean age 71.0±8.2 years; 6 men) performed before TEVAR and during follow-up (median 0.1 months, interquartile range 0.1-5.8). Lengths of the ascending aorta, the aortic arch, and the descending aorta were measured. Diameters and areas were computed at the sinotubular junction, brachiocephalic trunk, left subclavian artery, and the celiac trunk. Pulsatile longitudinal and circumferential strains were quantified as systolic increments of length and circumference divided by the corresponding diastolic values., Results: Average pulsatile longitudinal strain ranged from 1.4% to 7.1%, was highest in the arch (p<0.001), and increased after TEVAR by 77% in the arch (7.1%±2.5% vs 12.5%±5.1%, p=0.04) and by 69% in the ascending aorta (5.6±2.3% vs 9.4±4.4%, p=0.06). Average pulsatile circumferential strain ranged from 3.6% to 5.0% before TEVAR and did not differ significantly throughout the thoracic aorta; there was a nonsignificant increase after TEVAR at the unstented sinotubular junction (5.0%±1.4% vs 6.3%±1.0%, p=0.18), with a significant increase at the celiac trunk (3.6%±1.8% vs 6.2%±1.8%, p=0.02). Pulsatile circumferential strains within stented segments were deemed unreliable due to image artifacts., Conclusion: TEVAR was associated with an increase of pulsatile longitudinal strains (in the arch) and circumferential strains (at the celiac trunk) in unstented aortic segments. These observations suggest increased pulsatile wall stress after TEVAR in segments adjacent to the device, which may contribute to the understanding of stent-graft-related complications such as retrograde dissection, aneurysm formation, and rupture.

Objectives: To quantify the impact of thoracic endovascular aortic repair (TEVAR) on radial aortic strain with the aim of elucidating stent-graft-induced stiffening and complications., Methods: Twenty fresh thoracic porcine aortas were connected to a mock circulatory loop driven by a centrifugal flow pump. A high-definition camera captured diameters at five different pressure levels (100, 120, 140, 160, and 180 mmHg), before and after TEVAR. Three oversizing groups were created: 0-9% ( n  = 7), 10-19% ( n  = 6), and 20-29% ( n  = 6). Radial strain (or deformation) derived from diameter amplitude divided by baseline diameter at 100 mmHg. Uniaxial tensile testing evaluated Young's moduli of the specimens., Results: Radial strain was reduced after TEVAR within the stented segment by 49.4 ± 24.0% ( P  < 0.001). As result, a strain mismatch was observed between the stented segment and the proximal non-stented segment (7.0 ± 2.5% vs 11.8 ± 3.9%, P  < 0.001), whereas the distal non-stented segment was unaffected ( P  = 0.99). Stent-graft oversizing did not significantly affect the amount of strain reduction ( P  = 0.30). Tensile testing showed that the thoracic aortas tended to be more elastic proximally than distally ( P  = 0.11)., Conclusions: TEVAR stiffened the thoracic aorta by 2-fold. Such segmental stiffening may diminish the Windkessel function considerably and might be associated with TEVAR-related complications, including stent-graft-induced dissection and aneurysmal dilatation. These data may have implications for future stent-graft design, in particular for TEVAR of the highly compliant proximal thoracic aorta., (© The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Objective: Unplanned hospital readmissions following surgical interventions are associated with adverse events and contribute to increasing health care costs. Despite numerous studies defining risk factors following lower extremity bypass surgery, evidence regarding readmission after endovascular interventions is limited. This study aimed to identify predictors of 30-day unplanned readmission following infrainguinal endovascular interventions., Methods: We identified all patients undergoing an infrainguinal endovascular intervention in the targeted vascular module of the American College of Surgeons National Surgical Quality Improvement Program between 2012 and 2014. Perioperative outcomes were stratified by symptom status (chronic limb-threatening ischemia [CLI] vs claudication). Patients who died during index admission and those who remained in the hospital after 30 days were excluded. Indications for unplanned readmission related to the index procedure were evaluated. Multivariable logistic regression was used to identify preoperative and in-hospital (during index admission) risk factors of 30-day unplanned readmission., Results: There were 4449 patients who underwent infrainguinal endovascular intervention, of whom 2802 (63%) had CLI (66% tissue loss) and 1647 (37%) had claudication. The unplanned readmission rates for CLI and claudication patients were 16% (n = 447) and 6.5% (n = 107), respectively. Mortality after index admission was higher for readmitted patients compared with those not readmitted (CLI, 3.4% vs 0.7% [P < .001]; claudication, 2.8% vs 0.1% [P < .01]). Approximately 50% of all unplanned readmissions were related to the index procedure. Among CLI patients, the most common indication for readmission related to the index procedure was wound or infection related (42%), whereas patients with claudication were mainly readmitted for recurrent symptoms of peripheral vascular disease (28%). In patients with CLI, predictors of unplanned readmission included diabetes (odds ratio, 1.3; 95% confidence interval, 1.01-1.6), congestive heart failure (1.6; 1.1-2.5), renal insufficiency (1.7; 1.3-2.2), preoperative dialysis (1.4; 1.02-1.9), tibial angioplasty/stenting (1.3; 1.04-1.6), in-hospital bleeding (1.9; 1.04-3.5), in-hospital unplanned return to the operating room (1.9; 1.1-3.5), and discharge other than to home (1.5; 1.1-2.0). Risk factors for those with claudication were dependent functional status (3.5; 1.4-8.7), smoking (1.6; 1.02-2.5), diabetes (1.5; 1.01-2.3), preoperative dialysis (3.6; 1.6-8.3), procedure time exceeding 120 minutes (1.8; 1.1-2.7), in-hospital bleeding (2.9; 1.2-7.4), and in-hospital unplanned return to the operating room (3.4; 1.2-9.4)., Conclusions: Unplanned readmission after endovascular treatment is relatively common, especially in patients with CLI, and is associated with substantially increased mortality. Awareness of these risk factors will help providers identify patients at high risk who may benefit from early surveillance, and prophylactic measures focused on decreasing postoperative complications may reduce the rate of readmission., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Purpose: To investigate the total fluoroscopy time and radiation exposure dose during endovascular aortic repairs using mobile, fixed, or fixed C-arms with 3-dimensional image fusion (3D-IF)., Methods: A systematic search was performed to identify original articles reporting fluoroscopy time (FT) and the kerma area product (KAP) during endovascular aortic repairs. Data were grouped by noncomplex or complex (fenestrated, branched, or chimney) repairs and stratified by type of C-arm. The search identified 27 articles containing 51 study groups (35 noncomplex and 16 complex) that included 3444 patients. Random-effects meta-analysis and meta-regression models were used to calculate the pooled mean estimates of KAP and FT, as well as any effect of equipment or type of intervention. Results are presented with the 95% confidence interval and the statistical heterogeneity (I 2 )., Results: Within the noncomplex procedure studies, a significant (p<0.001) increase was found in the pooled mean KAP estimate in the fixed C-arm group (181 Gy·cm 2 , 95% CI 129 to 233; I 2 =99.7) compared with the mobile C-arm (78 Gy·cm 2 , 95% CI 59.6 to 97.3; I 2 =99.6). For complex cases, use of 3D-IF showed a significantly (p<0.001) lower mean KAP (139 Gy·cm 2 , 95% CI 85 to 191; I 2 =94%) compared to using fixed C-arms without 3D-IF (487 Gy·cm 2 , 95% CI 331 to 643; I 2 =94%)., Conclusion: For equivalent fluoroscopy times, the use of a fixed C-arm in noncomplex procedures leads to higher patient radiation doses compared to a mobile C-arm. Complex procedures, which are predominantly performed using fixed C-arms, are associated with the highest radiation dose per intervention. Using fixed C-arms combined with 3D-IF techniques during complex cases might seem an adequate method to compensate for the higher radiation doses measured when a fixed C-arm is used., (© The Author(s) 2016.)

Introduction: Thoracic aortic stent grafts are orders of magnitude stiffer than the native aorta. These devices have been associated with acute hypertension, elevated pulse pressure, cardiac remodelling and reduced coronary perfusion. However, a systematic assessment of such cardiovascular effects of thoracic endovascular aortic repair (TEVAR) is missing. The CardiOvascular Remodelling following Endovascular aortic repair (CORE) study aims to (1) quantify cardiovascular remodelling following TEVAR and compare echocardiography against MRI, the reference method; (2) validate computational modelling of cardiovascular haemodynamics following TEVAR using clinical measurements, and virtually assess the impact of more compliant stent grafts on cardiovascular haemodynamics; and (3) investigate diagnostic accuracy of ECG and serum biomarkers for cardiac remodelling compared to MRI., Methods and Analysis: This is a prospective, nonrandomised, observational cohort study. We will use MRI, CT, echocardiography, intraluminal pressures, ECG, computational modelling and serum biomarkers to assess cardiovascular remodelling in two groups of patients with degenerative thoracic aneurysms or penetrating aortic ulcers: (1) patients managed with TEVAR and (2) control patients managed with medical therapy alone. Power analysis revealed a minimum total sample size of 20 patients (α=0.05, power=0.97) to observe significant left ventricular mass increase following TEVAR after 1 year. Consequently, we will include 12 patients in both groups. Advanced MRI sequences will be used to assess myocardial and aortic strain and distensibility, myocardial perfusion and aortic flow. ECG, echocardiography and serum biomarkers will be collected and compared against the imaging data. Computational models will be constructed from each patient imaging data, analysed and validated. All measurements will be collected at baseline (prior to TEVAR) and 1-year follow-up. The expected study period is 3 years., Ethics and Dissemination: This study has been approved by the University of Michigan IRB. The results will be disseminated through scientific journals and conference presentations., Trial Registration Number: NCT02735720., Competing Interests: Conflicts of Interest: None declared., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Background: Endovascular treatment of peripheral arterial disease (PAD) still yields unsatisfactory patency rates. Recent new developments include the use of bioresorbable stents. The objective of this study was to provide an overview of currently available data on the use of bioresorbable stents in lower limb PAD and to summarize the needs for future research focus., Methods: A systematic search in the databases of MEDLINE, Embase, and the Cochrane Library was performed. Studies using predefined inclusion and exclusion criteria were included and critically appraised by two independent reviewers. Inclusion criteria were (1) original data on (2) bioresorbable stents in (3) lower limb arteries including the iliac tract. Primary end points were safety and feasibility of bioresorbable stents, including 30-day adverse events. Secondary end points included radial force, bioresorption process, long-term primary and secondary patency, and clinical outcomes, such as amputation rate, Rutherford category, and ankle-brachial index improvement., Results: Seven published studies with a total of 316 patients were included, and five conference abstracts including 272 patients were assessed. Median follow-up time was 12 months. Overall technical success rate was 99% (range, 95.0%-100%). The 30-day adverse event rates were reported in 5.0% of patients (range, 0%-13.3%); these included one death, two major amputations, and seven reinterventions. Mean primary patency rate was 61.6% in the femoral arteries (range, 32.1%-80.0%) after 6 to 12 months compared with 50.3% in below-the-knee lesions (range, 31.8%-92.9%). Secondary patency rates were 91.5% (range, 84%-97.1%) and 72.1% (range, 62.9%-100%), respectively. The 1-year amputation rate was 3.0% in the whole group (range, 0%-12.4%)., Conclusions: Experience with the use of bioresorbable stents in PAD is still limited and is investigated only in small studies. The use of bioresorbable stents in PAD appears to be feasible and safe. With current published results, we are unable to fully answer all of the questions about the future use of bioresorbable stents in PAD, and use should be limited to study-related cases in PAD., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Stanford type B aortic dissection (TBAD) is a life-threatening aortic disease. The initial management goal is to prevent aortic rupture, propagation of the dissection, and symptoms by reducing the heart rate and blood pressure. Uncomplicated TBAD patients require prompt medical management to prevent aortic dilatation or rupture during subsequent follow-up. Complicated TBAD patients require immediate invasive management to prevent death or injury caused by rupture or malperfusion. Recent developments in diagnosis and management have reduced mortality related to TBAD considerably. In particular, the introduction of thoracic stent-grafts has shifted the management from surgical to endovascular repair, contributing to a fourfold increase in early survival in complicated TBAD. Furthermore, endovascular repair is now considered in some uncomplicated TBAD patients in addition to optimal medical therapy. For more challenging aortic dissection patients with involvement of the aortic arch, hybrid approaches, combining open and endovascular repair, have had promising results. Regardless of the chosen management strategy, strict antihypertensive control should be administered to all TBAD patients in addition to close imaging surveillance. Future developments in stent-graft design, medical therapy, surgical and hybrid techniques, imaging, and genetic screening may improve the outcomes of TBAD patients even further. We present a comprehensive review of the recommended management strategy based on current evidence in the literature., (© The Author(s) 2016.)

The introduction of fenestrated stent grafts (SGs) to treat abdominal aortic aneurysms (AAAs) with short proximal necks began in 1999. Nowadays, the whole visceral aorta can be treated totally by endovascular means. The established use of fenestrated devices to treat complex AAAs as a first-line management option has been previously reported. An up-to-date evaluation of the literature was performed including all types of publications regarding the use of fenestrated technology to repair complex AAAs. Fenestrated repair is now an established alternative to hybrid/chimney/snorkel repairs. However, specific criteria and prerequisites are required for the use and improvement of this method. Multiple device morphologies have been used incorporating the visceral arteries in various combinations. This modular strategy connects different devices (bridging covered stents and bifurcated SGs) with the aortic main body, thus excluding the aneurysm from the circulation. Precise deployment of the fenestrated SG is mandatory for successful visceral vessel revascularization. Accurate SG sizing and customization, a high level of technical skill, and facilities with modern imaging techniques including 3D road mapping and dedicated hybrid rooms are required. Most experience has been with the custom-made Zenith Cook platform, although off-the-shelf devices have been recently implanted. More complex repairs have been performed over the last few years, but device complexity has also increased. Perioperative, mid-term, and a few recently reported long-term results are encouraging. Secondary interventions remain the main problem, similar to that observed after traditional endovascular abdominal aortic aneurysm repair (EVAR)., (© The Author(s) 2016.)

Background: Currently, the optimal management strategy for chronic type B aortic dissections (CBAD) is unknown. Therefore, we systematically reviewed the literature to compare results of open surgical repair (OSR), standard thoracic endovascular aortic repair (TEVAR) or branched and fenestrated TEVAR (BEVAR/FEVAR) for CBAD., Methods: EMBASE and MEDLINE databases were searched for eligible studies between January 2000 and October 2015. Studies describing outcomes of OSR, TEVAR, B/FEVAR, or all, for CBAD patients initially treated with medical therapy, were included. Primary endpoints were early mortality, and one-year and five-year survival. Secondary endpoints included occurrence of complications. Furthermore, a Time until Treatment Equipoise (TUTE) graph was constructed., Results: Thirty-five articles were selected for systematic review. A total of 1081 OSR patients, 1397 TEVAR patients and 61 B/FEVAR patients were identified. Early mortality ranged from 5.6% to 21.0% for OSR, 0.0% to 13.7% for TEVAR, and 0.0% to 9.7% for B/FEVAR. For OSR, one-year and five-year survival ranged 72.0%-92.0% and 53.0%-86.7%, respectively. For TEVAR, one-year survival was 82.9%-100.0% and five-year survival 70.0%-88.9%. For B/FEVAR only one-year survival was available, ranging between 76.4% and 100.0%. Most common postoperative complications included stroke (OSR 0.0%-13.3%, TEVAR 0.0%-11.8%), spinal cord ischemia (OSR 0.0%-16.4%, TEVAR 0.0%-12.5%, B/FEVAR 0.0%-12.9%) and acute renal failure (OSR 0.0%-33.3%, TEVAR 0.0%-34.4%, B/FEVAR 0.0%-3.2%). Most common long-term complications after OSR included aneurysm formation (5.8%-20.0%) and new type A dissection (1.7-2.2%). Early complications after TEVAR included retrograde dissection (0.0%-7.1%), malperfusion (1.3%-9.4%), cardiac complications (0.0%-5.9%) and rupture (0.5%-5.0%). Most common long-term complications after TEVAR were rupture (0.5%-7.1%), endoleaks (0.0%-15.8%) and cardiac complications (5.9%-7.1%). No short-term aortic rupture or malperfusion was observed after B/FEVAR. Long-term complications included malperfusion (6.5%) and endoleaks (0.0%-66.7%). Reintervention rates after OSR, TEVAR and B/FEVAR were 5.8%-29.0%, 4.3%-47.4% and 0.0%-53.3%, respectively. TUTE for OSR was 2.7 years, for TEVAR 9.9 months and for B/FEVAR 10.3 months., Conclusion: We found a limited early survival benefit of standard TEVAR over OSR for CBAD. Complication rates after TEVAR are higher, but complications after OSR are usually more serious. Initial experiences with B/FEVAR show its feasibility, but long-term results are needed to compare it to OSR and standard TEVAR. We conclude that optimal treatment of CBAD remains debatable and merits a patient specific decision. TUTE seems a feasible and useful tool to better understand management outcomes of CBAD.

Long-term outcomes of elective thoracic endovascular aortic repair (TEVAR) for degenerative thoracic aortic aneurysms (TAA) are not well defined. A review of the literature on the follow-up outcomes of elective TEVAR for degenerative TAA resulted in 22 relevant articles. Two- and five-year freedom from aneurysm-related death varied between 93.0% and 100.0%, and 82.4% to 92.7%, respectively. Two-year and five-year all-cause survival ranged between 68.0% and 97.2% and 47.0% to 78.0%, respectively. Follow-up ranged between 17.3 and 66.0 months. Most common endograft-related complication was endoleak, with reported rate between 1.4% and 14.8% during six months up to five years of follow-up. Endovascular reinterventions were reported in 0.0-32.3%, secondary open surgery was needed in 0.0% to 4.7% during follow-up. Aneurysm-related survival rates after elective TEVAR for degenerative TAA are acceptable. However, reported incidences of endograft-related complications vary considerably in the literature, but the majority can be managed with conservative treatment or additional endovascular procedures., (© The Author(s) 2015.)

The aim of this study is to give an overview of current knowledge regarding abdominal aortic aneurysm (AAA) growth after endovascular aortic aneurysm repair (EVAR) that could potentially lead to aortic rupture. A search on Pubmed was performed. A total of 705 articles were found after initial search, of which 49 were included in the final selection. Reports on the incidence of aneurysm enlargement after EVAR vary between 0.2% and 41%. Continuous growth could lead to rupture of the aneurysm sac. There are several supposed risk factors for growth after EVAR. Endoleaks remain a hot topic as these could lead to persistent pressurization of the aneurysm sac causing growth. Various types of endoleak exist, of which each kind requires an individual treatment approach, other risk factors for aneurysm growth include endotension and the use of EVAR outside instructions for use (IFU). Reinterventions after EVAR are common; however, it is unclear how frequently these are required because of aneurysm enlargement. Aneurysm enlargement after EVAR remains a subject of debate, as this could lead to aortic rupture. This emphasizes the need for life-long radiologic surveillance during follow-up. Aortic growth after EVAR is often a result of endoleak; however, in some cases, no endoleak is detectable. Endoleak in combination with aortic growth >5 mm generally requires reintervention. A cause of concern is the liberal use of endovascular devices outside the IFU that may result in increased risk of AAA growth after EVAR., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Purpose: To evaluate the effect of radiation dose reduction with the Allura ClarityIQ image processing technology for fixed C-arms in comparison with a mobile C-arm and an Allura fixed C-arm without ClarityIQ technology during endovascular aneurysm repair (EVAR) procedures., Methods: Radiation dose data from 85 patients (mean age 74.2±7.8 years; 68 men) undergoing EVAR with mobile and fixed C-arm fluoroscopy were retrospectively analyzed. The radiation dose parameters included the kerma area product (KAP), fluoroscopic time (FT), and number of digital subtraction angiography (DSA) frames (FrDSA). KAPtotal consisted of KAPfluoro (KAP for fluoroscopic imaging) and KAPDSA (KAP for DSA and single shots). Linear regression analysis was used to explore differences in the association of KAP with the FT, FrDSA, and body mass index (BMI) among the 3 C-arms., Results: The mean KAPtotal values for mobile, Allura C-arm, and AlluraClarity C-arm for noncomplex EVARs were 56±39, 245±142, and 157±120 Gy·cm(2) (p<0.001); for complex EVARs, the values were 110±43, 874±653, and 598±319 Gy·cm(2) (p<0.001), respectively. On average, KAPfluoro tripled when the mobile C-arm was replaced by the fixed C-arm. There were no significant differences in the KAPfluoro adjusted for the FT between Allura and AlluraClarity (p=0.69). However, there was a major 61% reduction in KAPDSA from 1.36 Gy·cm(2) per DSA frame for Allura to 0.54 Gy·cm(2) per DSA frame with AlluraClarity (p=0.03). For the mobile C-arm, BMI was not associated with KAP (p=0.13). The associations of BMI with KAPfluoro and KAPDSA were significant for both fixed C-arms but were more robust for Allura compared to AlluraClarity (p=0.02 for KAPfluoro and p<0.001 for KAPDSA)., Conclusion: Changing a mobile C-arm for a fixed C-arm in a hybrid operating suite increased the average intraoperative dose during EVAR. Upgrading the Allura fixed C-arm with ClarityIQ technology resulted in a 61% reduction in the radiation per DSA frame., (© The Author(s) 2015.)

Purpose: To determine the safety and efficacy of off-the-shelf fenestrated/branched grafts (OSFGs) and physician-modified stent-grafts (PMSGs) for the treatment of complex abdominal aortic aneurysms., Methods: A systematic search of the MEDLINE database via PubMed from January 2001 through March 2015 retrieved 23 relevant articles evaluating the clinical outcomes following the management of patients with pararenal or thoracoabdominal aortic aneurysms. The 15 articles on PMSGs and 8 on OSFGs contained data on 308 patients (mean age 72.93±2.89 years; 213 men). The safety endpoint was major adverse events; the efficacy outcome measure was clinical treatment success (aneurysm exclusion without type I/III endoleak, permanent paralysis, long-term dialysis, or unresolved major complications). Extracted outcome data were pooled and compared between groups; data are given as the pooled proportions and 95% confidence interval (CI). Clinical data are presented as the weighted mean., Results: Of the 308 patients analyzed, almost one third were operated on an emergency basis. The mean aneurysm diameters were 75.9±17.3 mm (range 56-115) for the PMSGs and 68.1±13.7 mm (range 60-100) for the OSFGs. A total of 936 renal and visceral vessels were targeted. Major adverse events (safety) occurred in 24 (12.8%) PMSG patients (95% CI 8.6% to 18.7%) and in 9 (7.4%) OSFG patients (95% CI 3.7% to 14%). Clinical treatment success (efficacy) was observed in 171/187 (91.4%) PMSG patients (95% CI 86.2% to 94.9%) and in 115/121 (95%) OSFG patients (95% CI 89.1% to 98.0%). Corresponding cumulative 30-day target vessel and branch stent perfusion rates were 97.2% (95% CI 95.1% to 98.4%) and 97.6% (95% CI 95.5% to 98.8%) for the PMSG group and 99.6% (95% CI 98.3% to 99.9%) and 98.4% (95% CI 96.5% to 99.4%) for the OSFG group. Six (3.2%) deaths occurred in the PMSG group only; 2 (1.1%) were aneurysm related. Overall branch patency was recorded in 443/458 (96.7%) and in 468/478 (97.9%) of target vessels in the PMSG and OSFG groups, respectively., Conclusion: Off-the-shelf and physician-modified technology seems effective and safe, in both the elective and acute settings, for the treatment of complex aortic aneurysms. Future research within a randomized trial should investigate the true limitations of these devices., (© The Author(s) 2015.)

Objective: Isolated renal artery aneurysms are rare, and controversy remains about indications for surgical repair. Little is known about the impact of endovascular therapy on selection of patients and outcomes of renal artery aneurysms., Methods: We identified all patients undergoing open or endovascular repair of isolated renal artery aneurysms in the Nationwide Inpatient Sample from 1988 to 2011 for epidemiologic analysis. Elective cases were selected from the period 2000 to 2011 to create comparable cohorts for outcome comparison. We identified all patients with a primary diagnosis of renal artery aneurysms undergoing open surgery (reconstruction or nephrectomy) or endovascular repair (coil or stent). Patients with concomitant aortic aneurysms or dissections were excluded. We evaluated patient characteristics, management, and in-hospital outcomes for open and endovascular repair, and we examined changes in management and outcomes over time., Results: We identified 6234 renal artery aneurysm repairs between 1988 and 2011. Total repairs increased after the introduction of endovascular repair (8.4 in 1988 to 13.8 in 2011 per 10 million U.S. population; P = .03). Endovascular repair increased from 0 in 1988 to 6.4 in 2011 per 10 million U.S. population (P < .0001). However, there was no concomitant decrease in open surgery (5.5 in 1988 to 7.4 in 2011 per 10 million U.S. population; P = .28). From 2000 to 2011, there were 1627 open and 1082 endovascular elective repairs. Patients undergoing endovascular repair were more likely to have a history of coronary artery disease (18% vs 11%; P < .001), prior myocardial infarction (5.2% vs 1.8%; P < .001), and renal failure (7.7% vs 3.3%; P < .001). In-hospital mortality was 1.8% for endovascular repair, 0.9% for open reconstruction (P = .037), and 5.4% for nephrectomy (P < .001 compared with all revascularization). Complication rates were 12.4% for open repair vs 10.5% for endovascular repair (P = .134), including more cardiac (2.2% vs 0.6%; P = .001) and peripheral vascular complications (0.6% vs 0.0%; P = .014) with open repair. Open repair had a longer length of stay (6.0 vs 4.6 days; P < .001). After adjustment for other predictors of mortality, including age (odds ratio [OR], 1.05 per decade; 95% confidence interval [CI], 1.0-1.1; P = .001), heart failure (OR, 7.0; 95% CI, 3.1-16.0; P < .001), and dysrhythmia (OR, 5.9; 95% CI, 2.0-16.8; P = .005), endovascular repair was still not protective (OR, 1.6; 95% CI, 0.8-3.2; P = .145)., Conclusions: More renal artery aneurysms are being treated with the advent of endovascular techniques, without a reduction in operative mortality or a reduction in open surgery. Indications for repair of renal artery aneurysms should be re-evaluated., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Thoracic endovascular aortic repair (TEVAR) has evolved into an established treatment option for type B aortic dissection (TBAD) since it was first introduced 2 decades ago. Morbidity and mortality have decreased due to the minimally invasive character of TEVAR, with adequate stabilization of the dissection, restoration of true lumen perfusion, and subsequent positive aortic remodeling. However, several studies have reported severe setbacks of this technique. Indeed, little is known about the biomechanical behavior of implanted thoracic stent-grafts and the impact on the vascular system. This study sought to systematically review the performance and behavior of implanted thoracic stent-grafts and related biomechanical aortic changes in TBAD patients in order to update current knowledge and future perspectives., (© The Author(s) 2015.)

Objective: Prior studies suggest that percutaneous access for endovascular abdominal aortic aneurysm repair (pEVAR) offers significant operative and postoperative benefits compared with femoral cutdown (cEVAR). National data on this topic, however, are limited. We compared patient selection and outcomes for elective pEVAR and cEVAR., Methods: We identified all patients undergoing either pEVAR (bilateral percutaneous access, whether successful or not) or cEVAR (at least one planned groin cutdown) for abdominal aortic aneurysms from January 2011 to December 2013 in the Targeted Vascular data set from the American College of Surgeons National Surgical Quality Improvement Program database. Emergent cases, ruptures, cases with an iliac conduit, and cases with a preoperative wound infection were excluded. Groups were compared by χ(2) test or t-test or the Mann-Whitney test where appropriate., Results: We identified 4112 patients undergoing elective EVAR, 3004 cEVAR patients (73%) and 1108 pEVAR patients (27%). Of all EVAR patients, 26% had bilateral percutaneous access; 1.0% had attempted percutaneous access converted to cutdown (4% of pEVARs); and the remainder had a planned cutdown, 63.9% bilateral and 9.1% unilateral. There were no significant differences in age, gender, aneurysm diameter, or prior open abdominal surgery. Patients undergoing cEVAR were less likely to have congestive heart failure (1.5% vs 2.4%; P = .04) but more likely to undergo any concomitant procedure during surgery (32% vs 26%; P < .01) than patients undergoing pEVAR. Postoperatively, pEVAR patients had shorter operative time (mean, 135 vs 152 minutes; P < .01), shorter length of stay (median, 1 day vs 2 days; P < .01), and fewer wound complications (2.1% vs 1.0%; P = .02). On multivariable analysis, the only predictor of percutaneous access failure was performance of any concomitant procedure (odds ratio, 2.0; 95% confidence interval, 1.0-4.0; P = .04)., Conclusions: Currently, one in four patients treated at Targeted Vascular National Surgical Quality Improvement Program centers are getting pEVAR, which is associated with a high success rate, shorter operation time, shorter length of stay, and fewer wound complications compared with cEVAR., (Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: Open repair (OPEN) and conservative management (CONS) have been the treatments of choice for splenic artery aneurysms (SAAs) for many years. Endovascular repair (EV) has been increasingly used with good short-term results. In this study, we evaluated the cost-effectiveness of OPEN, EV, and CONS for the treatment of SAAs., Methods: A decision analysis model was developed using TreeAge Pro 2013 software (TreeAge Inc, Williamstown, Mass) to evaluate the cost-effectiveness of the different treatments for SAAs. A hypothetical cohort of 10,000 55-year-old female patients with SAAs was assessed in the reference-case analysis. Perioperative mortality, disease-specific mortality rates, complications, rupture risks, and reinterventions were retrieved from a recent and extensive meta-analysis. Costs were analyzed with the 2014 Medicare database. The willingness to pay was set to $60,000/quality-adjusted life years (QALYs). Outcomes evaluated were QALYs, costs from the health care perspective, and the incremental cost-effectiveness ratio (ICER). Extensive sensitivity analyses were performed and different clinical scenarios evaluated. Probabilistic sensitivity analysis was performed to include the uncertainty around the variables. A flowchart for clinical decision-making was developed., Results: For a 55-year-old female patient with a SAA, EV has the highest QALYs (11.32; 95% credibility interval [CI], 9.52-13.17), followed by OPEN (10.48; 95% CI, 8.75-12.25) and CONS (10.39; 95% CI, 8.96-11.87). The difference in effect for 55-year-old female patients between EV and OPEN is 0.84 QALY (95% CI, 0.42-1.34), comparable with 10 months in perfect health. EV is more effective and less costly than OPEN and more effective and more expensive compared with CONS, with an ICER of $17,154/QALY. Moreover, OPEN, with an ICER of $223,166/QALY, is not cost-effective compared with CONS. In elderly individuals (age >78 years), the ICER of EV vs CONS is $60,503/QALY and increases further with age, making EV no longer cost-effective. Very elderly patients (age >93 years) have higher QALYs and lower costs when treated with CONS. The EV group has the highest number of expected reinterventions, followed by CONS and OPEN, and the number of expected reinterventions decreases with age., Conclusions: EV is the most cost-effective treatment for most patient groups with SAAs, independent of the sex and risk profile of the patient. EV is superior to OPEN, being both cost-saving and more effective in all age groups. Elderly patients should be considered for CONS, based on the high costs in relation to the very small gain in health when treated with EV. The very elderly should be treated with CONS., (Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Purpose: To examine the long-term outcomes of bare metal stent placement for exclusion of extracranial internal carotid artery (ICA) aneurysms., Methods: From 2006 to 2011, 7 consecutive symptomatic patients (4 men; mean age 52 years) with surgically inaccessible extracranial ICA aneurysms were treated with a bare stent at a single center. Patients received clopidogrel for 3 months after the procedure and aspirin for life. Clinical follow-up with duplex ultrasound and/or computed tomographic angiography was performed at 3, 6, and 12 months and yearly thereafter., Results: All procedures were technically successful; no neurological complications occurred. After 6 months, there was complete thrombosis of the aneurysm in all except one case. In this asymptomatic patient, the residual active flow was successfully obliterated by additional coil embolization. Over a mean follow-up of 57 ± 22 months, all patients were alive and free of local or central neurological symptoms. All stents were patent, and thrombosis of the aneurysms was complete., Conclusion: In this small series, treatment of extracranial ICA aneurysms with a bare stent seems technically feasible and safe. All treated extracranial ICA aneurysms were excluded by primary intervention or secondary coil embolization., (© The Author(s) 2015.)

Objective: This study reviewed the current developments in manual tracking and robotic navigation technologies for application in endovascular aortic aneurysm repair (EVAR)., Methods: EMBASE and MEDLINE databases were searched for studies reporting manual tracking or robotic navigation systems that are able to manipulate endovascular surgical tools during abdominal or thoracic aortic aneurysm repair. Reports were grouped by the navigation systems and categorized into phantom, animal, and clinical studies. First, the general characteristics of each system were compared. Second, target registration error and deployment error were used to compare the accuracy of the tracking systems. Third, all systems were reviewed for fluoroscopy time (FT), radiation dose, and contrast volumes, if reported, in rigid and nonrigid studies. Fourth, vascular cannulation performance of the systems was compared, studying cannulation time, Imperial College Complex Cannulation Scoring Tool score, and the number of wall hits and catheter movements within rigid studies., Results: Of 721 articles and references found, 18 studies of four different navigation systems were included: the Aurora (Northern Digital, Waterloo, Ontario, Canada) tracking system, the StealthStation (Medtronic Inc, Minneapolis, Minn) tracking system, an ultrasound localization tracking system, and the Sensei (Hansen Medical, Mountain View, Calif) steerable remote-controlled robotic navigation system. The mean tracking accuracy averaged 1 mm for the three manual tracking systems measured in a rigid environment. An increase of target registration error reaching >3 mm was reported when measured in a nonrigid experimental environment or due to external distortion factors. Except within small-animal studies or case studies, no evidence was found on reduction of clinical outcome parameters, such as FT, radiation dose, and contrast volumes, within clinical EVAR. A comparison of vascular cannulation performance in rigid studies revealed that the Sensei robotic system might have an advantage during advanced cannulation compared with standard cannulation within complex cannulations tasks., Conclusions: This review summarizes the current studies on manual tracking and robotic navigation systems for application in EVAR. The main focus of these systems is improving aortic vessel cannulation, required in complex EVAR, in which the robotic system with the improved steerability is favored over manual tracking systems or conventional cannulation. All reviewed tracking systems still require X-ray for anatomic imaging, stent graft deployment, and device registration. Although the current reviewed endovascular navigation systems have shown their potential in phantom and animal studies, clinical trials are too limited to conclude that these systems can improve EVAR outcomes or that they can systematically reduce FTs, radiation doses, and contrast volumes during (complex) EVAR., (Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: True splenic artery aneurysms (SAAs) are a rare but potentially fatal pathology. For many years, open repair (OPEN) and conservative management (CONS) were the treatments of choice, but throughout the last decade endovascular repair (EV) has become increasingly used. The purpose of the present study was to perform a systematic review and meta-analysis evaluating the outcomes of the three major treatment modalities (OPEN, EV, and CONS) for the management of SAAs., Methods: A systematic review of all studies describing the outcomes of SAAs treated with OPEN, EV, or CONS was performed using seven large medical databases. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed to ensure a high-quality review. All articles were subject to critical appraisal for relevance, validity, and availability of data regarding characteristics and outcomes. All data were systematically pooled, and meta-analyses were performed on several outcomes, including early and late mortality, complications, and number of reinterventions., Results: Original data of 1321 patients with true SAAs were identified in 47 articles. OPEN contained 511 patients (38.7%) in 31 articles, followed by 425 patients (32.2%) in CONS in 16 articles and 385 patients (29.1%) in EV in 33 articles. The CONS group had fewer symptomatic patients (9.5% vs 28.7% in OPEN and 28.8% in EV; P < .001) and fewer ruptured aneurysms (0.2% vs 18.4% in OPEN and 8.8% in EV; P < .001), but no significant differences were found in existing comorbidities. CONS patients were usually older and had smaller-sized aneurysms than patients in the OPEN and EV groups. The only identified difference in baseline characteristics between OPEN and EV was the number of ruptured aneurysms (18.4% vs 8.8%; P < .001). OPEN had a higher 30-day mortality than EV (5.1% vs 0.6%; P < .001), whereas minor complications occurred in a larger number of the EV patients. EV required more reinterventions per year (3.2%) compared with OPEN (0.5%) and CONS (1.2%; P < .001). The late mortality rate was higher in patients treated with CONS (4.9% vs 2.1% in OPEN and 1.4% in EV; P = .04)., Conclusions: EV of SAA has better short-term results compared with OPEN, including significantly lower perioperative mortality. OPEN is associated with fewer late complications and fewer reinterventions during follow-up. Patients treated with CONS showed a higher late mortality rate. Ruptured SAAs are predictors of a significantly higher perioperative mortality compared with nonruptured SAAs in the OPEN and EV groups., (Copyright © 2014 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Purpose: To quantitatively evaluate the impact of thoracic endovascular aortic repair (TEVAR) on aortic hemodynamics, focusing on the implications of a bird-beak configuration., Methods: Pre- and postoperative CTA images from a patient treated with TEVAR for post-dissecting thoracic aortic aneurysm were used to evaluate the anatomical changes induced by the stent-graft and to generate the computational network essential for computational fluid dynamics (CFD) analysis. These analyses focused on the bird-beak configuration, flow distribution into the supra-aortic branches, and narrowing of the distal descending thoracic aorta. Three different CFD analyses (A: preoperative lumen, B: postoperative lumen, and C: postoperative lumen computed without stenosis) were compared at 3 time points during the cardiac cycle (maximum acceleration of blood flow, systolic peak, and maximum deceleration of blood flow)., Results: Postoperatively, disturbance of flow was reduced at the bird-beak location due to boundary conditions and change of geometry after TEVAR. Stent-graft protrusion with partial coverage of the origin of the left subclavian artery produced a disturbance of flow in this vessel. Strong velocity increase and flow disturbance were found at the aortic narrowing in the descending thoracic aorta when comparing B and C, while no effect was seen on aortic arch hemodynamics., Conclusion: CFD may help physicians to understand aortic hemodynamic changes after TEVAR, including the change in aortic arch geometry, the effects of a bird-beak configuration, the supra-aortic flow distribution, and the aortic true lumen dynamics. This study is the first step in establishing a computational framework that, when completed with patient-specific data, will allow us to study thoracic aortic pathologies and their endovascular management.

Objective: Open revascularization (OR) has been the treatment of choice for chronic mesenteric ischemia (CMI) for many years, but endovascular revascularization (EV) has been increasingly used with good short-term results. In this study, we evaluated the comparative effectiveness and cost-effectiveness of EV and OR in patients with CMI refractory to conservative management., Methods: A Markov-state transition model was developed using TreeAge Pro 2012 (TreeAge Inc, Williamstown, Mass) to simulate a hypothetical cohort of 10,000 65-year-old female patients with CMI requiring treatment with either OR or EV. Data for the model, including perioperative and long-term overall mortality risks, disease-specific mortality risks, complications, and reintervention and patency rates, were retrieved from original studies and systematic reviews about CMI. Costs were analyzed with the 2013 Medicare database. Outcomes evaluated were quality-adjusted life-years (QALYs), costs from the health care perspective, and the incremental cost-effectiveness ratio. Extensive sensitivity analyses were performed and different clinical scenarios evaluated. Probabilistic sensitivity analysis was performed to assess robustness of the model., Results: For a reference-case 65-year-old female patient with CMI and an average risk for operation, EV is preferred with 10.03 QALYs (95% credibility interval [CI], 9.76-10.29) vs 9.59 after OR (95% CI, 9.29-9.87). The difference is comparable to 5 months in perfect health: 0.44 QALY (95% CI, 0.13-0.76). For 65-year-old men, this was 8.71 QALYs (95% CI, 8.48-8.94) for EV vs 8.42 (95% CI, 8.14-8.63) for OR. Sensitivity analysis showed that for younger patients, EV results in a higher increase in QALYs compared with older patients. Total expected reinterventions per patient are 1.70 for EV vs 0.30 for OR. Total expected health care costs for the reference-case patient were $39,942 (95% CI, $28,509-$53,380) for OR and $38.217 (95% CI, $29,329-$48,309) for EV. For men, this was $39,375 (95% CI, $28,092-$52,853) for OR and $35,903 (95% CI, $27,685-$45,597) for EV. For patients younger than 60 years, EV is a more expensive treatment strategy compared with OR, but with an incremental cost-effectiveness ratio for EV of less than $60,000/QALY. For patients 60 years and older, EV dominated OR as preferential treatment because effectiveness was higher than for OR and costs were lower., Conclusions: The results of this decision analysis model suggest that EV is favored over OR for patients with CMI in all age groups. Although EV is associated with more expected reinterventions, EV appears to be cost-effective for all age groups., (Copyright © 2014 Society for Vascular Surgery. All rights reserved.)