Consensus statement on the interhospital transfer of patients with acute aortic syndrome: TRAVERSING Delphi study.

BACKGROUND: Standardisation of referral pathways and the transfer of patients with acute aortic syndromes (AAS) to regional centres are recommended by NHS England in the Acute Aortic Dissection Toolkit. The aim of the Transfer of Thoracic Aortic Vascular Emergencies to Regional Specialist INstitutes Group study was to establish an interdisciplinary consensus on the interhospital transfer of patients with AAS to specialist high-volume aortic centres. METHODS: Consensus on the key aspects of interhospital transfer of patients with AAS was established using the Delphi method, in line with Conducting and Reporting of Delphi Studies guidelines. A national patient charity for aortic dissection was involved in the design of the Delphi study. Vascular and cardiothoracic surgeons, emergency physicians, interventional radiologists, cardiologists, intensivists and anaesthetists in the United Kingdom were invited to participate via their respective professional societies. RESULTS: Three consecutive rounds of an electronic Delphi survey were completed by 212, 101 and 58 respondents, respectively. Using predefined consensus criteria, 60 out of 117 (51%) statements from the survey were included in the consensus statement. The study concluded that patients can be taken directly to a specialist aortic centre if they have typical symptoms of AAS on the background of known aortic disease or previous aortic intervention. Accepted patients should be transferred in a category 2 ambulance (response time <18 min), ideally accompanied by transfer-trained personnel or Adult Critical Care Transfer Services. A clear plan should be agreed in case of a cardiac arrest occurring during the transfer. Patients should reach the aortic centre within 4 hours of the initial referral from their local hospital. CONCLUSIONS: This consensus statement is the first set of national interdisciplinary recommendations on the interhospital transfer of patients with AAS. Its implementation is likely to contribute to safer and more standardised emergency referral pathways to regional high-volume specialist aortic units.

Umbrella review and meta-analysis of reconstructed individual patient data of mortality following conventional endovascular and open surgical repair of infrarenal abdominal aortic aneurysm.

OBJECTIVES: This umbrella review aims to quality assess published meta-analyses, conduct a de-novo meta-analysis of the available randomized control trials (RCTs), and test the hypothesis that there is a long-term difference in mortality between OSR and EVAR. METHODS: A systematic search was conducted in MEDLINE and EMBASE's bibliographic databases (June 2022). Data were extracted using standardized extraction forms. The methodological quality of publications was assessed using the ROBIS tool. Data were analyzed with 'one-stage' and 'two-stage' approaches. RESULTS: According to two-stage analysis, EVAR has significantly favorable mortality for up to four years (increasing evidence). Subsequently, until the longest available time period, there is no difference between EVAR and OSR; all the results are statistically non-significant.In one stage analysis, the Cox model demonstrated a non-significant (weak evidence) hazard ratio of 1.03 (95% confidence interval [CI]: 0.94-1.12) in favor of OSR. The best-fitting parametric model (generalized gamma), leads to an hazard ratio of 0.97 (95% CI: 0.93-1.01) in favor of EVAR, with the results approaching significance (weak evidence). CONCLUSION: The results of this umbrella systematic review and meta-analysis failed to demonstrate any difference in long-term mortality following planned EVAR, compared with OSR of infrarenal AAA.

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.

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.

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.

Total psoas area predicts medium-term mortality after lower limb revascularization.

BACKGROUND: Analytic morphometry is a novel concept in perioperative risk assessment. Low core muscle mass assessed by morphometry is associated with frailty and has been demonstrated to be an independent predictor of postoperative complications and mortality in oncologic, transplant, and aneurysm surgery. We aimed to study associations between core muscle mass and complication rates, length of hospital stay, and survival after surgical lower limb revascularization. METHODS: In this retrospective cohort study, 263 patients considered for surgical lower limb revascularization between January 2013 and December 2014 underwent cross-sectional imaging. Total psoas area (TPA) was measured on computed tomography angiograms at the level of the fourth lumbar vertebra by two independent observers blinded to clinical details. Clinical information was collected from patients' notes and the electronic medical record. Cox and logistic regression analyses were used to estimate the effect of clinical factors and psoas muscle area on survival, complication rates, and prolonged hospital stay after surgical lower limb revascularization. RESULTS: Data from 263 patients were analyzed. The American Society of Anesthesiologists score (hazard ratio [HR], 3.05; confidence interval [CI], 1.69-5.50; P < .001), emergency status (HR, 2.26; CI, 1.21-4.22; P = .011), lowest TPA quartile (HR, 1.89; CI, 1.07-3.35; P = .028), and Fontaine stage (HR, 1.63; CI, 1.04-2.53; P = .031) were found to be independent predictors of survival. Low TPA was not associated with increased rate of postoperative complications or prolonged hospital stay. CONCLUSIONS: Psoas muscle area may help identify patients with a shorter life expectancy after lower limb revascularization, but its role in predicting postoperative complications or length of hospital admission seems to be limited.

Late Rupture of Abdominal Aortic Aneurysm After Previous Endovascular Repair: A Systematic Review and Meta-analysis.

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

Aortic Dehiscence During Endovascular Sealing for Ruptured Abdominal Aortic Aneurysms.

PURPOSE: To present a case of aneurysm disruption during endovascular sealing of a ruptured abdominal aortic aneurysm. CASE REPORT: A 91-year-old woman presented with a ruptured abdominal aortic aneurysm. Her aneurysm morphology was unsuitable for standard or fenestrated endovascular repair, whereas open repair was considered to have an increased perioperative risk owing to multiple comorbidities. The Nellix endovascular sealing system was used. The balloon-expandable stent-grafts were deployed, but in the presence of aneurysm rupture, it was decided not to prefill the endobags with saline. The patient developed hypotension during endobag filling, which resolved once target pressure was reached. The procedure was completed uneventfully, and the completion angiogram revealed no endoleak. The time from guidewire insertion to completion angiogram was 24 minutes. Over the following days, she developed a gradual drop in hemoglobin, and computed tomographic angiography revealed an increased retroperitoneal hematoma and pronounced disruption of the calcified rim of the aortic sac compared to the preoperative imaging. She was managed with supportive treatment, demonstrating remarkable progress. She remains in good health 4 months later. CONCLUSION: Endovascular sealing can be used in patients with ruptured abdominal aortic aneurysm. Intraoperative endobag saline prefill should be avoided to minimize the risk of aortic wall disruption.

Sheath-shunt technique for avoiding lower limb ischemia during complex endovascular aneurysm repair.

Complex aortic aneurysms are now being repaired by endovascular techniques, albeit with a potentially increased risk of lower limb ischemia-reperfusion injury. We report a simple technique to maintain perfusion to the lower limb during endovascular repair, using one additional introducer sheath placed antegrade, distal to the stent graft introduction site, and connected to the side arm of the working sheath in the contralateral artery. This allows continuous perfusion of the limb distal to the main stent graft introduction site. In our initial experience with 12 cases, with confirmed occlusion of the native arterial system by the stent graft introducer sheath, arterial occlusion time was 165 ± 84 minutes. Use of the sheath-shunt technique resulted in pulsatile flow in all cases, with an average flow of 42.2 ± 13.2 mL/min, and actual ischemia time was reduced to 14 ± 11 minutes. There were no complications related to the use of this technique. Given the limited risk of this technique coupled with a potential benefit, we propose its consideration in patients undergoing complex endovascular repair.

Total endograft replacement of aortic arch.

Total endovascular replacement of the aortic arch is a complex procedure that is often favoured when the pathology anatomy precludes a standard median sternotomy. Here we present the case of endograft repair in a 79 year old male with 6.5 cm arch aneurysm and 5.4 cm descending thoracoabdominal aneurysm. Following bilateral carotid-subclavian bypasses, a long 7 Fr sheath was advanced into the descending aorta through the common iliac artery purse string. A double curved long Lunderquist wire was guided to deep within the left ventricle, and the endograft carefully advanced over the wire. The graft was radiologically orientated, and deployed under asystolic conditions. Retrograde cannulation of the branches were accomplished, with carotid sheath placed into the branches followed by bridging stents. The graft delivery system was then removed. This approach obviates the need for a sternotomy, cumbersome extra-anatomic debranching, and hypothermic circulatory arrest.

Evaluating training for a simulated team in complex whole procedure simulations in the endovascular suite.

INTRODUCTION: Simulators supporting the development of technical skills for complex procedures are gaining prominence. Safe performance of complex procedures requires effective team interactions. Our research group creates 'whole' procedure simulations to produce the psychological fidelity of clinical settings. Recruitment of real interventional team (IT) members has proved challenging. Actors as a simulated team are expensive. We hypothesised that medical students and trainees in a vascular unit could authentically portray members of the endovascular suite for carotid stenting. METHODS: This paper describes the evaluation of a training programme for a simulated IT. Participants rated the extent to which programmes objectives were met and realism of simulations. Researchers' field notes provided insight into strengths and weaknesses of the programme. RESULTS: Seven members from the vascular unit undertook training. Learning objectives were largely met. Nineteen simulations with 13 interventionalists were performed. Realism levels were at least moderate. Simulated IT members reported increased understanding of teamwork and roles in the endovascular suite. DISCUSSION: A simulated IT proved feasible. Authentic psychological fidelity complemented the physical fidelity of the simulated suite. Although there were areas for development in training, this approach might contribute considerably to interventionalist training and increase knowledge and skills of vascular trainees and medical students.

Cognitive training improves clinically relevant outcomes during simulated endovascular procedures.

OBJECTIVES: Virtual reality (VR) simulation has been suggested to objectively assess endovascular skills. The aim of this study was to determine the impact of cognitive training on technical performance of inexperienced subjects on a commercially available VR simulator (VIST, Vascular Intervention Simulation Trainer, Mentice, Gothenburg, Sweden). METHODS: Forty-seven subjects treated an identical virtual iliac artery stenosis endovascularly. Surgical trainees without endovascular experience were allocated to two training protocols: group A(1) (n = 10) received a 45 minute didactic session followed by an expert demonstration of the procedure that included error-based learning, whereas group A(2) (n = 10) was only given a demonstration of an iliac dilation and stent procedure. All trainees performed the intervention immediately following the expert demonstration. Twenty-seven endovascular physicians were recruited (>100 endovascular interventions). Performance was assessed using the quantitative (procedure and fluoroscopy time) and qualitative (stent/vessel ratio and residual stenosis) assessment parameters recorded by the simulator. RESULTS: The end-product (qualitative metrics) in the cognitive-skills group A(1) was similar to those of the endovascular physicians, though A(2) performed significantly worse than the physicians (group B): stent/vessel ratio (A(1) 0.89 vs B 0.96, P = .960; A(2) 0.66 vs B 0.96, P = .001) and residual stenosis (A(1) 11 vs B 4%, P = .511; A(2) 35 vs B 4%, P < .001). Group A(1) took longer to perform the procedure (A(1) 982 vs B 441 seconds, P < .001), with greater use of fluoroscopy than group B (A(1) 609 vs B 189 seconds, P < .001) whereas group A(2) performed the intervention as quickly as group B (A(2) 358 vs B 441 seconds, P = .192) but used less fluoroscopy (A(2) 120 vs 189 seconds, P = .002). CONCLUSION: Cognitive-skills training significantly improves the quality of end-product on a VR endovascular simulator, and is fundamental prior to assessment of inexperienced subjects.

Should we train the trainers? Results of a randomized trial.

BACKGROUND: The development of efficient training methods in surgery is increasingly important. The effectiveness of training trainers is unclear. This study was designed to determine the effect on their trainees' performance of instructing trainers in a specific cognitive training method. STUDY DESIGN: Ten trainers from a university teaching hospital were randomized to train novices on a one-to-one basis in a simulated procedure using either a four-step cognitive method or their own unspecified method. Thirty trainees were randomly assigned to either a cognitive or standard trainer. After training, trainees were assessed on performing the procedure using a task-specific checklist, a global rating scale, and time taken to complete the procedure. RESULTS: Trainees who were trained using the specific cognitive method completed the procedure in a faster time (mean 331 seconds [SD 37 seconds] versus 426 seconds [SD 66 seconds]) and with higher global rating scores (mean 23.25 seconds [SD 3.7 seconds] versus 20.5 seconds [SD 4.5 seconds]) compared with those taught by a standard method. CONCLUSIONS: Instructing trainers in a cognitive training method results in a significant improvement in training outcomes.

Endovascular skills training and assessment.

OBJECTIVE: Evolving endovascular therapies have transformed the management of vascular disease. At the same time, the increasing use of non-invasive vascular imaging techniques has reduced the opportunities to gain the required basic wire and catheter handling skills by performing diagnostic catheterizations. This article reviews the evidence for alternative tools currently available for endovascular skills training and assessment. METHODS: A literature search was performed on PubMed using combinations of the following keywords; endovascular, skills, training, simulation, assessment and learning curve. Additional articles were retrieved from the reference lists of identified papers as well as discussion with experts in the arena of medical education. RESULTS: Available alternatives to training on patients include synthetic models, anesthetized animals, human cadavers and virtual reality (VR) simulation. VR simulation is a useful tool enabling objective demonstration of improved skills performance both in simulated performance and in subsequent in-vivo performance. Assessment modalities reviewed include time action analysis, error analysis, global rating scales, procedure specific checklists and VR simulators. Assessment in training has been widely validated using VR simulation. Rating scales and checklists are presently the only assessment modalities that have demonstrated utility outside the training lab. CONCLUSION: The tools required for a structured proficiency based endovascular training curriculum are already available. Organization of training programs needs to evolve to make full use of modern simulation capability for technical and non-technical skills training.