Editor's Choice - Comparison of Open Surgery and Endovascular Techniques for Juxtarenal and Complex Neck Aortic Aneurysms: The UK COMPlex AneurySm Study (UK-COMPASS) - Peri-operative and Midterm Outcomes.

OBJECTIVE: Treatment of juxtarenal and complex neck abdominal aortic aneurysms (AAAs) is now commonly by endovascular rather than open surgical repair (OSR). Published comparisons show poor validity and scientific precision. UK-COMPASS is a comparative cohort study of endovascular treatments vs. OSR for patients with an AAA unsuitable for standard on label endovascular aneurysm repair (EVAR). METHODS: All procedures for AAA in England (November 2017 to October 2019) were identified, AAA anatomy assessed in a Corelab, peri-operative risk scores determined, and propensity scoring used to identify patients suitable for either endovascular treatment or OSR. Patients were stratified by aneurysm neck length (0 - 4 mm, 5 - 9 mm, or ≥ 10 mm) and operative risk; the highest quartile was considered high risk and the remainder standard risk. Death was the primary outcome measure. Endovascular treatments included fenestrated EVAR (FEVAR) and off label standard EVAR (± adjuncts). RESULTS: Among 8 994 patients, 2 757 had AAAs that were juxtarenal, short neck, or complex neck in morphology. Propensity score stratification and adjustment method comparisons included 1 916 patients. Widespread off label use of standard EVAR devices was noted (35.6% of patients). The adjusted peri-operative mortality rate was 2.9%, lower for EVAR (1.2%; p = .001) and FEVAR (2.2%; p = .001) than OSR (4.5%). In standard risk patients with a 0 - 4 mm neck, the mortality rate was 7.4% following OSR and 2.3% following FEVAR. Differences were smaller for patients with a neck length ≥ 5 mm: 2.1% OSR vs. 1.0% FEVAR. At 3.5 years of follow up, the overall mortality rate was 20.7% in the whole study population, higher following FEVAR (27.6%) and EVAR (25.2%) than after OSR (14.2%). However, in the 0 - 4 mm neck subgroup, overall survival remained equivalent. The aneurysm related mortality rate was equivalent between treatments, but re-intervention was more common after EVAR and FEVAR than OSR. CONCLUSION: FEVAR proves notably safer than OSR in the peri-operative period for juxtarenal aneurysms (0 - 4 mm neck length), with comparable midterm survival. For patients with short neck (5 - 9 mm) and complex neck (≥ 10 mm) AAAs, overall survival was worse in endovascularly treated patients compared with OSR despite relative peri-operative safety. This warrants further research and a re-appraisal of the current clinical application of endovascular strategies, particularly in patients with poor general survival outlook owing to comorbidity and age.

Fractured Sealing Rings in a Fenestrated Anaconda Stent-Graft.

An 81 year-old man presented with an asymptomatic juxtrarenal abdominal aortic aneurysm and was subsequently treated with a fenestrated endovascular Anaconda stent-graft. Surveillance imaging within the first postoperative year demonstrated a lower proximal sealing ring fracture. In the second postoperative surveillance year, the upper proximal sealing ring was also fractured with extension of the wire into the right paravertebral space. Despite these sealing ring fractures, there were no endoleak nor visceral stent complications and the patient continued on standard surveillance protocols. There are an increasing number of reports of fractured proximal sealing rings with the fenestrated Anaconda platform. Those analysing the surveillance scans of patients treated with this device should stay vigilant for the development of this complication.

Editor's Choice - Comparison of Open, Standard, and Complex Endovascular Aortic Repair Treatments for Juxtarenal/Short Neck Aneurysms: A Systematic Review and Network Meta-Analysis.

OBJECTIVE: Abdominal aortic aneurysms (AAAs) with adverse morphology of the aneurysm neck are "complex". Techniques employed to repair complex aneurysms include open surgical repair (OSR) and a number of on label endovascular techniques such as fenestrated endovascular aneurysm repair (FEVAR) and endovascular aneurysm repair (EVAR) with adjuncts (including chimneys and endo-anchors), as well as off label use of standard EVAR. The aim was to conduct a network meta-analysis (NMA) of published comparative outcomes. DATA SOURCES: An electronic search was performed in Embase, MEDLINE, and the Cochrane Central Register of Controlled Trials (CENTRAL). These databases were interrogated using the PubMed interface and the Healthcare Databases Advanced Search (HDAS) interface developed by the National Institute of Health and Care Excellence. REVIEW METHODS: Online databases were interrogated up to April 2020. Studies were included if they compared outcomes between at least two methods of repair for complex aneurysms (those with at least one adverse neck feature: absent/short neck, conicality, angulation, calcification, large diameter, and thrombus). The primary outcome measure was peri-operative death. Pre-registration was done in PROSPERO (CRD42020177482). RESULTS: The search identified 24 observational studies and 7854 patients who underwent OSR, FEVAR, off label EVAR, or chimney EVAR. No comparative studies included EVAR with endo-anchors. NMA was performed on 23 studies that reported outcomes of aneurysms with short/absent infrarenal neck. Compared with OSR, off label EVAR (relative risk [RR] 0.10, 95% confidence interval [CI] 0.01 - 0.41) and FEVAR (RR 0.62, 95% CI 0.32-0.94) were associated with lower peri-operative mortality. This difference was not seen at the midterm follow up (30 months). Compared with OSR, FEVAR was associated with a lower peri-operative myocardial infarction (MI) rate (RR 0.37, 95% CI 0.16 - 0.62) but a higher midterm re-intervention rate (hazard ratio 1.65, 95% CI 1.04 - 2.66). All studies had a "moderate" or "high" risk of bias. Confidence in the network findings (GRADE) was generally "low". CONCLUSION: This NMA demonstrated a peri-operative survival benefit for off label EVAR and FEVAR compared with OSR, potentially due to reduced risk of MI. FEVAR carries a greater midterm re-intervention risk than OSR, with potential implications for cost effectiveness. There is paucity of comparative data for cases with adverse neck features other than short length.

A risk-adjusted and anatomically stratified cohort comparison study of open surgery, endovascular techniques and medical management for juxtarenal aortic aneurysms-the UK COMPlex AneurySm Study (UK-COMPASS): a study protocol.

INTRODUCTION: In one-third of all abdominal aortic aneurysms (AAAs), the aneurysm neck is short (juxtarenal) or shows other adverse anatomical features rendering operations more complex, hazardous and expensive. Surgical options include open surgical repair and endovascular aneurysm repair (EVAR) techniques including fenestrated EVAR, EVAR with adjuncts (chimneys/endoanchors) and off-label standard EVAR. The aim of the UK COMPlex AneurySm Study (UK-COMPASS) is to answer the research question identified by the National Institute for Health Research Health Technology Assessment (NIHR HTA) Programme: 'What is the clinical and cost-effectiveness of strategies for the management of juxtarenal AAA, including fenestrated endovascular repair?' METHODS AND ANALYSIS: UK-COMPASS is a cohort study comparing clinical and cost-effectiveness of different strategies used to manage complex AAAs with stratification of physiological fitness and anatomical complexity, with statistical correction for baseline risk and indication biases. There are two data streams. First, a stream of routinely collected data from Hospital Episode Statistics and National Vascular Registry (NVR). Preoperative CT scans of all patients who underwent elective AAA repair in England between 1 November 2017 and 31 October 2019 are subjected to Corelab analysis to accurately identify and include every complex aneurysm treated. Second, a site-reported data stream regarding quality of life and treatment costs from prospectively recruited patients across England. Site recruitment also includes patients with complex aneurysms larger than 55 mm diameter in whom an operation is deferred (medical management). The primary outcome measure is perioperative all-cause mortality. Follow-up will be to a median of 5 years. ETHICS AND DISSEMINATION: The study has received full regulatory approvals from a Research Ethics Committee, the Confidentiality Advisory Group and the Health Research Authority. Data sharing agreements are in place with National Health Service Digital and the NVR. Dissemination will be via NIHR HTA reporting, peer-reviewed journals and conferences. TRIAL REGISTRATION NUMBER: ISRCTN85731188.

Characterising the incidence and mode of visceral stent failure after fenestrated endovascular aneurysm repair (FEVAR).

BACKGROUND: In FEVAR, visceral stents provide continuity and maintain perfusion between the main body of the stent and the respective visceral artery. The aim of this study was to characterise the incidence and mode of visceral stent failure (type Ic endoleak, type IIIa endoleak, stenosis/kink, fracture, crush and occlusion) after FEVAR in a large cohort of patients at a high-volume centre. METHODS: A retrospective review of visceral stents placed during FEVAR over 15 years (February 2003-December 2018) was performed. Kaplan-Meier analyses of freedom from visceral stent-related complications were performed. The outcomes between graft configurations of varying complexity were compared, as were the outcomes of different stent types and different visceral vessels. RESULTS: Visceral stent complications occurred in 47/236 patients (19.9%) and 54/653 stents (8.3%). Median follow up was 3.7 years (IQR 1.7-5.3 years). There was no difference in visceral stent complication rate between renal, SMA and coeliac arteries. Visceral stent complications were more frequent in more complex grafts compared to less complex grafts. Visceral stent complications were more frequent in uncovered stents compared to covered stents. Visceral stent-related endoleaks (type Ic and type IIIa) occurred exclusively around renal artery stents. The most common modes of failure with SMA stents were kinking and fracture, whereas with coeliac artery stents it was external crush. CONCLUSION: Visceral stent complications after FEVAR are common and merit continued and close long-term surveillance. The mode of visceral stent failure varies across the vessels in which the stents are located.

Laparoscopic Surgery Is Safe and Beneficial in True Functional High-Risk Patients with Colorectal Cancer: Utilization of Cardiopulmonary Exercise Test.

Background: Patients with colorectal cancer deemed to be high-risk may be denied an elective laparoscopic resection due to subjective reasons. A comparison of the 30-day outcomes in true functional high-risk patients who underwent either open or laparoscopic colorectal resection was undertaken. Materials and Methods: A retrospective cohort of all functional high-risk patients as assessed by cardiopulmonary exercise test between July 2015 and April 2018 were identified. Anaerobic threshold of <11 mL/kg/minute was used as a physiologic indicator to determine a high-risk patient. Adherence to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) was ensured. P values were computed via two-sided Fisher's exact test, and the exact Mann-Whitney U-test. Forest plots for relative risks with 95% confidence intervals were displayed on a log scale. Results: One hundred forty-six patients were identified as high-risk. Outcomes demonstrated a trend to laparoscopic benefit in all Clavien-Dindo grades of postoperative complications, but especially in severe complications of grades 3-4 (3.5% versus 10.2%). Readmissions demonstrated a trend to laparoscopic surgery benefit (7% versus 11.8%), as did mortality (1.7% versus 3.4%). The rate of surgery-site complications was higher after open surgery (42.1% versus 22.4%, P = .0201). Wound infections were observed more frequently after open surgery (12.5% versus 1.72%, P = .0280). The estimated risk of all-grade complications was significantly higher after open anterior rectal resection (63.0% versus 29.6%, P = .0281) and there was significantly shorter stay after laparoscopic right colectomy (5 v. 7 days, P = .0490). Conclusions: Laparoscopic approach for colorectal resections in high-risk patients is safe and beneficial compared to open surgery, especially in patients undergoing laparoscopic resection of the rectum and right colon.

Endovascular vs. Medical Management for Uncomplicated Acute and Sub-acute Type B Aortic Dissection: A Meta-analysis.

OBJECTIVE: The aim was to compare peri-operative and late outcomes of patients with acute and subacute uncomplicated type B aortic dissection (uTBAD) treated by thoracic endovascular aortic repair (TEVAR) or best medical therapy (BMT). METHODS: This was a Systematic review and meta-analysis of observational studies and randomised controlled trials (RCTs). The review was undertaken according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered with the International Prospective Register of Systematic Reviews (number: CRD42018094607). Multiple electronic databases were searched to identify relevant articles. The methodological quality of the included studies was assessed. The primary outcome measures were early mortality and re-intervention, late all cause and aorta related mortality, and re-intervention. Meta-analysis was used to produce pooled odds ratios (OR) or risk difference (RD) for peri-operative outcomes. Random effects models were applied. For late outcomes a time to event meta-analysis was conducted using the inverse variance model, reporting the results as hazard ratios (HR). RESULTS: Eight original articles from six studies encompassing 14 706 patients (1 066 TEVARs) were eligible for inclusion. There were no statistically significant differences between TEVAR and BMT with regards to inpatient mortality (RD 0.01, 95% CI -0.01-0.02, p = .46), early re-intervention by TEVAR (RD 0.02, 95% CI -0.01-0.04, p = .19) or surgery (RD 0.00, 95% CI -0.01-0.01, p = 1.0). BMT was associated with a significantly lower risk of early stroke (OR 0.64, 95% CI 0.48-0.85, p = .002), whereas the risk of late all cause (HR 1.54, 95% CI 1.27-1.86, p < .001) and aorta related mortality (HR 2.71, 95% CI 1.49-4.94, p = .001) was significantly higher than with TEVAR. No suitable data regarding late aortic re-intervention was found for meta-analysis. CONCLUSION: Given the limited number and quality of suitable studies it remains uncertain whether TEVAR is beneficial in the management of acute/subacute uTBAD. Further research is required to understand which dissections would benefit from pre-emptive treatment.

A Systematic Review of Predictors of Reintervention After EVAR: Guidance for Risk-Stratified Surveillance.

BACKGROUND: Current surveillance protocols after endovascular aneurysm repair (EVAR) are ineffective and costly. Stratifying surveillance by individual risk of reintervention requires an understanding of the factors involved in developing post-EVAR complications. This systematic review assessed risk factors for reintervention after EVAR and proposals for stratified surveillance. METHODS: A systematic search according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was performed using EMBASE and MEDLINE databases to identify studies reporting on risk factors predicting reintervention after EVAR and proposals for stratified surveillance. RESULTS: Twenty-nine studies reporting on 39 898 patients met the primary inclusion criteria for reporting predictors of reintervention or aortic complications with or without suggestions for stratified surveillance. Five secondary studies described external validation of risk scores for reintervention or aortic complications. There was great heterogeneity in reporting risk factors identified at the pre-EVAR, intraoperative, and post-EVAR stages of treatment, although large preoperative abdominal aortic aneurysm diameter was the most commonly observed risk factor for reintervention after EVAR. CONCLUSION: Existing data on predictors of post-EVAR complications are generally of poor quality and largely derived from retrospective studies. Few studies describing suggestions for stratified surveillance have been subjected to external validation. There is a need to refine risk prediction for EVAR failure and to conduct prospective comparative studies of personalized surveillance with standard practice.

Bilateral Nephrectomy for Autosomal Dominant Polycystic Kidney Disease and Timing of Kidney Transplant: A Review of the Technical Advances in Surgical Management of Autosomal Dominant Polycystic Disease.

Autosomal dominant polycystic disease is a multisystem inherited condition affecting the kidneys and is an important cause of end-stage renal disease. Patients with autosomal dominant polycystic disease experience symptoms related to size and cystic nature of their kidneys, which can be difficult to manage. Traditionally, the only surgical option for management was open bilateral/unilateral native nephrectomy, which carried with it significant morbidity and mortality. Therefore, it was deemed unsafe and rarely performed. However, surgery for autosomal dominant polycystic disease has evolved rapidly with the advent of minimally invasive surgery and improved medical management of end-stage renal failure patients. Laparoscopic and hand-assisted laparoscopic techniques have been adopted and have demonstrated reduced morbidity. The timing of this intervention in relation to transplant is controversial and presents a major challenge in managing this patient population.

Appearance of the Nellix endovascular aneurysm sealing system on computed tomography: implications for postoperative imaging surveillance.

PURPOSE: To describe the imaging characteristics of the Nellix Endovascular Aneurysm Sealing (EVAS) System on serial computed tomography (CT) surveillance. METHODS: Sixty-eight patients undergoing EVAS were enrolled in a surveillance protocol that included CT scans prior to hospital discharge and at 3, 6, and 9 months postoperatively. Images were analyzed for the presence of gas within the endobag, endoleak, and for maximum radiodensity measured in Hounsfield units (HU) within the uppermost, middle, and lowermost regions of each endobag. RESULTS: Gas was seen within the endobags of all 68 EVAS repairs at the first postoperative CT compared with 2 (5.6%) of 36 undergoing the 3-month scan. The endobags appeared radiodense during initial imaging, and the median (interquartile range) radiodensity of the Nellix polymer decreased from 158.3 HU (149.5; 169.5) at the postoperative CT to 81.0 HU (74.0; 88.0) at 3 months, excluding 3 cases in which contrast pre-fill was utilized. Type I endoleak was seen at the periphery of the aneurysm sac or in the cleft between the endobags, with a substantially different appearance to endoleak after endovascular aneurysm repair. CONCLUSION: The evolution of CT appearances after EVAS was characteristic and predictable. The device endobags were initially radiodense, which may impact the detection of endoleak within 3 months of EVAS. Endoleaks after EVAS were seen in a different anatomical area to endoleaks after conventional stent-graft repair.

A Systematic Review and Meta-analysis of Endovascular Popliteal Aneurysm Repair Using the Hemobahn/Viabahn Stent-Graft.

PURPOSE: To perform an evidence synthesis study to assess outcomes of endovascular repair of popliteal artery aneurysms (PAAs) using the Hemobahn or Viabahn stent-graft. METHODS: A systematic literature review was conducted conforming to established standards to identify articles published between 1996 (the date of introduction of the Hemobahn stent-graft) and 2013 reporting stent-graft repair of PAAs in at least 10 patients. The data were pooled for Kaplan-Meier analysis of primary and secondary patency rates [presented with 95% confidence intervals (CIs)] as the primary outcomes. Random effects meta-analysis was performed for secondary outcomes that included rates of reintervention, endoleak, stent-graft fracture, and limb salvage. RESULTS: Fourteen studies reported outcomes for 514 PAAs. There was considerable heterogeneity in reporting standards among studies. Pooled primary and secondary patency rates were 69.4% (95% CI 63.3% to 76.2%) and 77.4% (95% CI 70.1% to 85.3%), respectively, at 5 years. Five studies (including only one randomized controlled trial) compared surgical to endovascular repair; no difference was found in primary patency on evidence synthesis (hazard ratio 1.30, 95% CI 0.79 to 12.14, p=0.189). CONCLUSION: Stent-graft repair provides a feasible treatment option for anatomically suitable PAAs. Further studies are required to optimize both patient selection and follow-up protocols.

Indications for renal autotransplant: an overview.

Advances in transplantation led to the first renal autotransplant in 1963 performed due to high ureteral injury sustained during aortic surgery. The procedure involves excision of the kidney and autologous re-implantation. Subsequently, multiple cases of renal autotransplantation have been reported in the literature for a range of indications. This reviews aims to assess the literature and experiences reported to assess the varying indications for renal autotransplant. The evidence and literature generated from experiences in this procedure are largely limited to case reports and relatively small or moderately sized case series. The main indications reported for performing autotransplant broadly includes renovascular disease, ureteral pathology and neoplastic disease. The advent of laparoscopic techniques and their implications on renal autotransplant also are discussed. Varying degrees of success are reported with this procedure with controversial issues surrounding this procedure remain, particularly in the area of neoplastic surgery. Renal autotransplant may be a useful last resort in preventing kidney loss in highly selected circumstances and when conventional methods have failed.

A systematic review and meta-analysis indicates underreporting of renal dysfunction following endovascular aneurysm repair.

Deterioration in renal function has been described after endovascular repair of abdominal aortic aneurysms (EVRs). The etiology is multifactorial and represents an important therapeutic target. A need exists to quantitatively summarize incidence and severity of renal dysfunction after EVR to allow better-informed attempts to preserve renal function and improve life expectancy. Here a systematic search was performed using Medline and Embase for renal function after EVR applying PRISMA statements. Univariate and multivariate random-effects meta-analyses were performed to estimate pooled postoperative changes in serum creatinine and creatinine clearance at four time points after EVR. Clinically relevant deterioration in renal function was also estimated at 1 year or more after EVR. Pooled probability of clinically relevant deterioration in renal function at 1 year or more was 18% (95% confidence interval of 14-23%, I2 of 82.5%). Serum creatinine increased after EVR by 0.05 mg/dl at 30 days/1 month, 0.09 mg/dl at 1 month to 1 year, and 0.11 mg/dl at 1 year or more (all significant). Creatinine clearance decreased after EVR by 5.65 ml/min at 1 month-1 year and by 6.58 ml/min at 1 year or more (both significant). Thus, renal dysfunction after EVR is common and merits attention.

Misdiagnosis of ruptured abdominal aortic aneurysm: systematic review and meta-analysis.

PURPOSE: To quantitatively summarize the incidence of misdiagnosis of ruptured abdominal aortic aneurysms (rAAA), the most common presenting features, and the commonest incorrect differential diagnoses. METHODS: A systematic search according to PRISMA guidelines was performed using EMBASE and MEDLINE databases to identify studies reporting the initial rate of misdiagnosis of patients with rAAA. Random-effects meta-analyses were performed to estimate the rate of misdiagnosis, presenting features, and commonest differential diagnoses. A sensitivity analysis was performed for studies reporting after 1990. RESULTS: Nine studies comprising 1109 patients contributed to the pooled analysis, which found a 42% incidence of rAAA misdiagnosis (95% CI 29% to 55%). In studies reporting after 1990, misdiagnosis was seen in 32% (95% CI 16% to 49%). The most common erroneous differential diagnoses were ureteric colic and myocardial infarction. Abdominal pain, shock, and a pulsatile mass were presenting features in 61% (49%-72%), 46% (32%-61%), and 45% (29%-62%) of rAAAs, respectively. CONCLUSION: The rate of misdiagnosis of rAAA has remained consistent over time and is concerning. There is a need for an effective clinical decision tool to enable accurate diagnosis and triage at the scene of the emergency.