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

BACKGROUND

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

METHODS

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

DISCUSSION

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

TRIAL REGISTRATION

ISRCTN13832085. Dec. 3, 2021.

Quality Assessment of Elective Abdominal Aortic Aneurysm Repair Patient Information on the Internet Using the Modified Ensuring Quality Information for Patients Tool

OBJECTIVE

This study aimed to assess the quality of patient information material regarding elective abdominal aortic aneurysm (AAA) repair on the internet using the Modified Ensuring Quality Information for Patients (MEQIP) tool.

METHODS

A qualitative assessment of internet based patient information was performed. The 12 most used search terms relating to AAA repair were identified using Google Trends, with the first 10 pages of websites retrieved for each term searched. Duplicates were removed, and information for patients undergoing elective AAA were selected. Further exclusion criteria were marketing material, academic journals, videos, and non-English language sites. The remaining websites were then MEQIP scored independently by two reviewers, producing a final score by consensus.

RESULTS

A total of 1 297 websites were identified, with 235 (18.1%) eligible for analysis. The median MEQIP score was 18 (interquartile range [IQR] 14, 21) out of a possible 36. The highest score was 33. The 99th percentile MEQIP scoring websites scored > 27, with four of these six sites representing online copies of hospital patient information leaflets, however hospital sites overall had lower median MEQIP scores than most other institution types. MEQIP subdomain median scores were: content, 8 (IQR 6, 11); identification, 3 (IQR 1, 3); and structure, 7 (IQR 6, 9). Of the analysed websites, 77.9% originated from the USA (median score 17) and 12.8% originated in the UK (median score 22). Search engine ranking was related to website institution type but had no correlation with MEQIP.

CONCLUSION

When assessed by the MEQIP tool, most websites regarding elective AAA repair are of questionable quality. This is in keeping with studies in other surgical and medical fields. Search engine ranking is not a reliable measure of quality of patient information material regarding elective AAA repair. Health practitioners should be aware of this issue as well as the whereabouts of high quality material to which patients can be directed.

Long Term Outcomes and Durability of Fenestrated Endovascular Aneurysm Repair: A Meta-analysis of Time to Event Data

OBJECTIVE

Despite widespread use, long term outcomes for fenestrated endovascular aneurysm repair (FEVAR) are uncertain. This meta-analysis reports long term survival, freedom from re-intervention, target vessel patency, and one year sac regression after FEVAR.

DATA SOURCES

Systematic review and meta-analysis to pool time to event data according to PRISMA guidelines. The study was registered with the international prospective register of systematic reviews (PROSPERO) (ID: CRD42023401468).

REVIEW METHODS

Medline, Embase, and Cochrane databases were searched from 1992 - 2023; articles were independently screened by two authors. Publication of complete time to event data for any outcome of interest was an inclusion criterion. Raw Kaplan-Meier probabilities were directly extracted from published curves and pooled by random effects. Risk of bias was assessed using ROBINS I and certainty with GRADE.

RESULTS

A total of 3 569 records were retrieved, 2 869 screened after duplicate removal, yielding 37 included studies (n = 4 371). The pooled mean age was 73.2 years (interquartile range [IQR] 72.2, 73.7) and 87.4% were male (95% confidence interval [CI] 85.8 - 88.9). Pooled Kaplan-Meier estimated probabilities of survival (n = 34 studies, n = 4 192 patients) at one, three, and five years were 91.6% (95% CI 90.2 - 92.9), 80.8% (95% CI 78.0 - 83.2), and 65.1% (95% CI 60.9 - 69.1). For freedom from re-intervention (n = 24, n = 3 211 patients) at one, three, and five years these were 90.2% (95% CI 87.3 - 92.7), 80.9% (95% CI 76.5 - 84.9), and 73.8% (95% CI 67.1 - 79.6). For target vessel patency (n = 13, n = 5805 target vessels) at one, three, and five years, these were 96.6% (95% CI 94.9 - 98.0), 94.5% (95% CI 91.7 - 96.7), and 93.1% (95% CI 89.3 - 96.0). Pooled estimate of sac regression (n = 8, n = 560) at one year was 40.2% (95% CI 28.9 - 52.7). Risk of bias was judged as moderate in 11 studies and low for the remaining 26.

CONCLUSION

There are moderate to low certainty data supporting reasonable long term outcome estimates following fenestrated endovascular aneurysm repair. Beyond five years there is a lack of data in the literature.

Predicting Prosthetic Mobility at Discharge From Rehabilitation Following Major Amputation in Vascular Surgery

OBJECTIVE

This study aimed to construct a decision aid to estimate the likelihood of independence with a prosthesis following rehabilitation for limb loss secondary to advanced ischaemia (acute or chronic limb threatening ischaemia) or diabetic foot disease (DFD). A secondary aim was to determine whether prosthetic independence is a surrogate marker of long term survival.

METHODS

A retrospective cohort study of a prospectively maintained database of unilateral amputations due to ischaemia or DFD entering rehabilitation between 2007 and 2020 was performed. Predictors of independent prosthetic mobility (IPM) were used in construction of the IPM prediction model, which underwent bootstrap internal and criterion validation through correlation with predictors of other measures of function: Timed Up and Go (TUG) and two minute walk test. Kaplan-Meier and Cox regression analyses were performed to address the secondary aim.

RESULTS

Of the 771 patients included, only 49.9% of amputees achieved IPM. Independent negative predictors of IPM were age > 75 years, female sex, higher amputation level, active malignancy, cerebrovascular disease, end stage renal disease, and cognitive impairment. The model yielded high discrimination (C statistic 0.778), and internal validation was demonstrated with bootstrapping (C statistic 0.778), confirming no over optimism. There was a strong correlation between IPM, TUG, and two minute distance and their predictors, confirming strong criterion validity. The IPM group had a median survival of 93.7 (80.7, 105) months, whereas the non-IPM group fared worse with a median survival of 56.6 (48.5, 66.7) months (p < .001).

CONCLUSION

An internally validated decision aid for estimating the likelihood of independence with a prosthesis after major amputation was constructed. A strong association between female sex and poorer prosthetic mobility was observed. Prosthetic function was shown to be a surrogate marker of long term survival. Future research will involve external validation studies to confirm the generalisability of the decision aid in clinical practice.

Amputation of the Unsalvageable Leg in Vascular Patients with Cancer

OBJECTIVES

The aim of this study was to compare outcomes of major lower limb amputation (MLA) in patients with and without cancer and with cancer patients receiving palliation over amputation for their unsalvageable limb.

METHODS

Cancer patients who underwent a major amputation or palliation between 2013 and 2018 were included. Comparison groups were cancer-MLA (active/managed cancers), non-cancer MLA (historic cancer or no cancer history) and cancer-palliation at presentation with unsalvageable limbs. Prospectively collected data was retrospectively analysed for outcomes including survival, postoperative complications, length of stay, suitability for rehabilitation and discharge destination.

RESULTS

262 (cancer and non-cancer) patients underwent MLA and 18 patients with cancer received palliation. Of those amputated, 26 (9.9%) had active or managed cancer, of which 12 were diagnosed in the 6 months before MLA. Cancer-MLA patients presented with more acute ischaemia compared to non-cancer patients. Median survival was significantly different between the cancer-MLA (14.1 [9.5 - 29.5, 95% CI] months), non-cancer MLA (57.7 [45 - 73.6, 95% CI] months) and cancer-palliation (.6 [.4 - 2.3, 95% CI] months) groups, P < .001. A significantly higher proportion of cancer-MLA patients (10/26, 38.5%) were deemed unsuitable for rehabilitation in post-operative assessment compared to non-cancer MLA (21/236, 8.9%) patients, P < .001. There was a variation in destinations of discharge, with a greater proportion of cancer-MLA patients (4/26, 15.4%) going to a nursing home compared to non-cancer MLA (10/236, 4.2%) patients, P = .016.

CONCLUSION

Cancer is prevalent among vascular amputees, with a large proportion being occult diagnoses. Cancer is associated with poorer outcomes following amputation, but survival remains significantly better compared to palliation in cancer patients presenting with unsalvageable limbs.

The Fate of Patients Opportunistically Screened for Abdominal Aortic Aneurysms During Echocardiogram or Arterial Duplex Scans

OBJECTIVE

To evaluate the long term outcomes of individuals who attended for transthoracic echocardiograms (TTEs) or lower limb arterial duplex scans (LLADS) and were opportunistically screened for abdominal aortic aneurysms (AAA).

METHODS

Follow up of a prospective single centre pilot cohort study conducted between December 2012 and September 2014 at a tertiary vascular centre in the United Kingdom. Men and Women aged 65 and over were invited to undergo AAA screening when attending hospital for TTE or LLADS. Screening was performed by ultrasonographic examination of the abdomen at the end of their planned scans. AAA was defined as an abdominal aorta outer wall to outer wall anteroposterior diameter of 30 mm or more. Patients were excluded if they had a known AAA or previous abdominal aorta intervention. Follow up outcomes were evaluated in December 2020.

RESULTS

762 patients were enrolled in this study; 486 had TTE and 276 patients had LLADS. The overall incidence of AAA was 54 (7.1%) in the combined cohort, 25 (5.1%) in the TTE group, and 29 (10.5%) in the LLADS group. After a median 7.6 years, two of the 54 AAAs received intervention in the form of endovascular repair. Three others reached treatment threshold but were managed conservatively. The overall intervention rate was 3.7% of detected AAAs. Adjusted mortality rates in those with AAA vs. without was 64.8% and 36%, respectively (hazard ratio [HR] 2.02, p < .001). Diabetes (HR 1.35, p = .015) and older age (HR 1.18, p = .17) were the other factors associated with death.

CONCLUSION

AAA is associated with a significantly increased mortality rate. Populations attending hospital for TTE or LLADS demonstrate a higher prevalence of AAA than population based screening; however, the proportion offered AAA intervention was low. Further research into opportunistic screening should target those more likely to undergo AAA repair, unless other interventions are demonstrated, to reduce the general increased mortality in AAA patients.

Association between statin-use and mobility and long-term survival after major lower limb amputation

AIM

The aim of this study was to determine if there is an association between statin-use and prosthetic mobility and long-term survival in patients receiving rehabilitation after major amputation for lower limb arterial disease.

METHODS

A retrospective analysis of prospectively maintained data (2008-2020) from a centre for rehabilitation was performed. Patients were grouped by statin-use status and sub-grouped by the combination of statin and antithrombotic drugs (antiplatelets or anticoagulants). Outcomes were prosthetic mobility (SIGAM score, timed-up-go and 2-min walking distance) and long-term survival. Regression, Kaplan-Meier and Cox-proportional hazard analyses were performed to test associations adjusted to confounders.

RESULTS

Of 771 patients, 499 (64.7%) were on a statin before amputation or prescribed a statin peri-operatively. Rate of statin-use was significantly lower among female (53.3%) compared to male (68.2%) patients, P < 0.001. Statin-use was associated with significantly better prosthetic independence (53.1% vs 44.1%, P = 0.017), timed-up-go (mean difference of 4 s, P = 0.04) and long-term survival HR 0.59 (0.48-0.72, P < 0.001). Significance persisted after adjusting for confounding factors and in subgroup analyses. The combination of statin with antiplatelet was associated with the most superior survival, HR 0.51 (0.40-0.65, P < 0.001). Sensitivity analysis (exclusion of non-users of prosthesis) showed that statin-use remained a significant indicator of longer survival, maximally when combined with antiplatelet use HR 0.52 (0.39-0.68, P < 0.001).

CONCLUSIONS

Statin-use is associated with better mobility and long-term survival in rehabilitees after limb loss, particularly when used in combination with antiplatelets. Significantly lower rates of statin-use were observed in female patients. Further research is warranted on gender disparities in statin-use and causality in their association with improved mobility and survival.

Timing of carotid endarterectomy and clinical outcomes

The timing of carotid endarterectomy (CEA) for symptomatic ipsilateral carotid artery stenosis has evolved in practice over time. Key landmark trials outlined the benefit of performing CEA in the recently symptomatic carotid artery stenosis, defined as revascularisation within 6 months of the index neurological event. Further evidence and sub-analysis demonstrate that performing CEA within 2 weeks of symptoms has the maximal benefit in reducing stroke free survival and is associated with a safe perioperative complication profile. This has translated into guideline recommendations and widespread clinical practice. The case for performing urgent CEA (within 48 hours of index neurological event) over early CEA (within 2 weeks) has been put forward and studied. Data examining perioperative complications for urgent CEA are mostly derived from retrospective single series studies. A moderate balance exists in the literature for the safety and risk of urgent CEA. Although many studies present acceptable perioperative stroke and mortality rates associated with urgent CEA, evidence still exists that the perioperative complications may not be insignificant. This is particularly the case if the presenting neurology is a stroke, rather than a transient ischaemic attack (TIA) or amaurosis fugax. This should be contextualised in the practice of modern aggressive medical therapy with dual antiplatelets and statins, with evidence suggesting a reduction in recurrent ischaemic events prior to surgical intervention. Careful patient selection, presenting neurology and medical therapy is likely to be a key feature in considering urgent CEA versus early CEA.

Development of novel patient selection criteria for a short stay endovascular aneurysm repair pathway: Improving patient selection for short stay endovascular aneurysm repair

Objectives

A short-stay endovascular aneurysm repair (SS-EVAR) pathway for infrarenal abdominal aortic aneurysms offers the potential to improve service efficiency and patient satisfaction by reducing the hospital length of stay. This study aimed to determine whether the implementation of a novel set of patient selection criteria for a theoretical SS-EVAR pathway could facilitate an expansion of the proportion of suitable patients, whilst maintaining patient safety and limiting unplanned emergency readmissions.

Methods

Two SS-EVAR selection criteria (low and high risk) were generated based upon patient pre-operative comorbidities. The low risk criteria essentially selected fit and healthy individuals, whereas the high risk criteria included patients with a range of comorbidities that could still theoretically enable enrolment onto a SS-EVAR pathway. A retrospective analysis, whereby both criteria were applied to all elective EVARs recorded in the National Vascular Registry between 2013 and 2016 at a single tertiary vascular unit was performed. Rates and timings of postoperative complications, reinterventions and unplanned readmissions for patients meeting each criteria were assessed.

Results

In total, 188 patients were included (92% male, mean age 75.4 ± 7.2 years). Twenty-nine patients (15%) met the low risk criteria. Two (7%) of these experienced an inpatient complication which were both detected within 24 h of operation (including one who required reintervention), and no patients in this group had an unplanned readmission within 30 days. One-hundred and ten patients (59%) met our high risk criteria and 19 (17%) experienced an inpatient complication, with 4 (4%) of these occurring beyond 24 h post-EVAR (three urinary problems and one acute on chronic kidney injury). Six (6%) of these patients required a reintervention; however, all of these complications were detected within 24 h. Two (2%) high risk cohort patients required unplanned readmission within 30 days for a femoral pseudoaneurysm and musculoskeletal back pain.

Conclusions

With high risk patient selection criteria and appropriate post-operative safeguards, up to 60% of infrarenal abdominal aortic aneurysms patients could be safely enrolled onto a next-day discharge SS-EVAR pathway with minimal readmissions, thus allowing more effective resource utilisation.

Recent developments and current controversies in short-stay endovascular aneurysm repair

INTRODUCTION

Short stay endovascular aneurysm repair pathways (SS-EVAR) provide potential advantages to both healthcare providers and patients. However, these benefits must be carefully balanced against the inherent risks to patient safety and tariff penalties associated with unplanned readmissions.

EVIDENCE ACQUISITION

A literature review was performed using the databases MEDLINE, Embase and Cochrane Library up until March 2019. Search terms used included "endovascular aneurysm repair," "aneurysm repair," "EVAR," "abdominal aortic aneurysm," "day case," "short stay," "fast track," and "ambulatory."

EVIDENCE SYNTHESIS

Nine relevant articles (including one prior review on the topic) were identified. This early data suggests that SS-EVAR is associated with good patient satisfaction and modest cost savings for healthcare providers. Patient selection, preoperative preparation and supported discharge with early follow-up are essential components of a SS-EVAR pathway. Increasingly, SS-EVAR tends to be delivered via bilateral percutaneous access and loco-regional anesthesia. Over 70% of patients enrolled onto SS-EVAR pathways successfully complete them. Long procedures with excessive blood loss are associated with pathway non-completion. All serious complications occur within 6 hours of the procedure and the mortality (0-1%), morbidity (8-58%) and readmission rates (0-6%) associated with SS-EVAR remains acceptably low. SS-EVAR pathways can be safely and effectively implemented in both teaching and non-teaching hospitals.

CONCLUSIONS

Short-stay EVAR pathways are safe and acceptable to patients. With appropriate selection of motivated patients, successful expedited discharge can be achieved with limited readmissions, thus facilitating increased resource efficiency and cost savings for healthcare providers.

Clinical examination and non-invasive screening tests in the diagnosis of peripheral artery disease in people with diabetes-related foot ulceration

AIM

Peripheral artery disease is common in people with diabetes-related foot ulceration and is a risk factor for amputation. The best method for the detection or exclusion of peripheral artery disease is unknown. This study investigated the utility of clinical examination and non-invasive bedside tests in screening for peripheral artery disease in diabetes-related foot ulceration.

METHODS

Some 60 people presenting with new-onset ulceration participated. Accuracy of pulses, ankle pressure, toe pressure, toe-brachial index (TBI), ankle-brachial pressure index (ABPI), pole test at ankle, transcutaneous oxygen pressure and distal tibial waveform on ultrasound were examined. The gold standard diagnostic test used was > 50% stenosis in any artery or monophasic flow distal to calcification in any ipsilateral vessel on duplex ultrasound.

RESULTS

The negative and positive likelihood ratios of pedal pulse assessment (0.75, 1.38) and the other clinical assessment tools were poor. The negative and positive likelihood ratios of ABPI (0.53, 1.69), transcutaneous oxygen pressure (1.10, 0.81) and ankle pressure (0.67, 2.25) were unsatisfactory. The lowest negative likelihood ratios were for tibial waveform assessment (0.15) and TBI (0.24). The highest positive likelihood ratios were for toe pressure (17.55) and pole test at the ankle (10.29) but the negative likelihood ratios were poor at 0.56 and 0.74.

CONCLUSIONS

Pulse assessment and ABPI have limited utility in the detection of peripheral artery disease in people with diabetes foot ulceration. TBI and distal tibial waveforms are useful for selecting those needing diagnostic testing.

Robotic Parathyroidectomy: A Prospective Case Control Study

Objective: 1) To assess the clinical efficacy and cost-effectiveness of the robotic approach compared with conventional targeted minimally invasive parathyroidectomy. 2) To evaluate whether the absence of a neck scar associated with the robotic approach offers any advantage(s) over conventional targeted minimally invasive parathyroidectomy. 3) To compare patient satisfaction between the 2 techniques.

Method: Prospective case control study of 30 patients that underwent targeted parathyroidectomy over 4 years (May 2009-February 2012) in a tertiary referral endocrine center. Fifteen patients had a robotic and 15 an endoscopic approach. Outcomes assessed included operative time, blood loss, biochemistry, pain, scar cosmesis, voice, quality of life, and complications.

Results: In all cases the parathyroid adenoma was successfully removed. There was 1 robotic conversion. Mean robotic operative time was approximately double that of the conventional approach. There were no significant differences in mean blood loss. Initial normalization of PTH and adjusted serum calcium levels occurred in 29 cases. The mean visual analogue score (VAS) for scar cosmesis was superior in the robotic cohort from 2 weeks (84% vs 65%, P < .01) to 1 year (94% vs 62%, P < .01). Postoperative VAS pain scores were similar in both groups ( P < .05). All EQ5 HD quality of life parameters significantly improved in both cohorts ( P < .05).

Conclusion: The robotic approach is a feasible “scar-less in the neck” alternative to conventional targeted minimally invasive parathyroidectomy with a superior cosmetic outcome. However, this novel approach is not suitable for all patients and appropriate patient selection is vital. Finally, the high cost of robotic parathyroidectomy currently hinders its more widespread use.

Face and Content Validation of a Virtual Reality Temporal Bone Simulator

Objective. To validate the VOXEL-MAN TempoSurg simulator for temporal bone dissection.

Study Design. Prospective international study.

Setting. Otolaryngology departments of 2 academic health care institutions in the United Kingdom and United States.

Subjects and Methods. Eighty-five subjects were recruited consisting of an experienced and referent group. Participants performed a standardized familiarization session and temporal bone dissection task. Realism, training effectiveness, and global impressions were evaluated across 21 domains using a 5-point Likert-type scale. A score of 4 was the minimum threshold for acceptability.

Results. The experienced group comprised 25 otolaryngology trainers who had performed 150 mastoid operations. The referent group comprised 60 trainees (mean otolaryngology experience of 2.9 years). Familiarization took longer in the experienced group ( P = .01). User-friendliness was positively rated (mean score 4.1). Seventy percent of participants rated anatomical appearance as acceptable. Trainers rated drill ergonomics worse than did trainees ( P = .01). Simulation temporal bone training scored highly (mean score 4.3). Surgical anatomy, drill navigation, and hand-eye coordination accounted for this. Trainees were more likely to recommend temporal bone simulation to a colleague than were trainers ( P = .01). Transferability of skills to the operating room was undecided (mean score 3.5).

Conclusion. Realism of the VOXEL-MAN virtual reality temporal bone simulator is suboptimal in its current version. Nonetheless, it represents a useful adjunct to existing training methods and is particularly beneficial for novice surgeons before performing cadaveric temporal bone dissection. Improvements in realism, specifically drill ergonomics and visual-spatial perception during deeper temporal bone dissection, are warranted.

Perioperative care of patients undergoing spinal stabilization with internal fixation (continuing education credit)

1. Low back pain affects approximately 80% of the adult population. There are between 200,000 and 500,000 spinal surgeries performed every year. 2. New spinal implant systems offer hope for persons with failed spinal surgery--as well as for those with spinal fractures, metastatic disease, and severe degenerative disorders. 3. Although complications can develop, the benefits of new spinal fixation systems far outweigh the problems.