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.

ACR Appropriateness Criteria® Thoracoabdominal Aortic Aneurysm or Dissection: Treatment Planning and Follow-Up.

As the incidence of thoracoabdominal aortic pathology (aneurysm and dissection) rises and the complexity of endovascular and surgical treatment options increases, imaging follow-up of patients remains crucial. Patients with thoracoabdominal aortic pathology without intervention should be monitored carefully for changes in aortic size or morphology that could portend rupture or other complication. Patients who are post endovascular or open surgical aortic repair should undergo follow-up imaging to evaluate for complications, endoleak, or recurrent pathology. Considering the quality of diagnostic data, CT angiography and MR angiography are the preferred imaging modalities for follow-up of thoracoabdominal aortic pathology for most patients. The extent of thoracoabdominal aortic pathology and its potential complications involve multiple regions of the body requiring imaging of the chest, abdomen, and pelvis in most patients. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Midterm Outcomes of BeGraft Stent Grafts Used as Bridging Stents in Fenestrated Endovascular Aortic Aneurysm Repair.

PURPOSE: Fenestrated endovascular aneurysm repair (fEVAR) is established for the treatment of juxtarenal, pararenal, and thoracoabdominal aortic aneurysms (TAAAs). Bridging stents are used to connect the main body of the stent graft to the aortic branch vessels. Complications related to the bridging stents compromise the durability of the repair and require urgent re-intervention. Here we present the midterm results of the BeGraft stent graft system used for fEVAR. MATERIALS AND METHOD: All consecutive patients treated with fEVAR and the current BeGraft Peripheral Stent Graft between November 2015 and September 2016 were included. RESULTS: Thirty-nine consecutive patients (38 men) were enrolled and 101 BeGraft second-generation stent grafts were implanted. The median aneurysm diameter was 60 mm (54.5-67.0 mm). Aneurysms were juxtarenal and pararenal (19/39, 48.1%), type 4 TAAA (3/39, 7.7%), type 1, 2, and 3 TAAA (7/39, 17.8%), type 5 TAAA (4/39, 10.2%), and 15.4% (6/39) had a type I endoleak following a previous EVAR. Fifty-five BeGrafts were implanted in mesenteric arteries (22 in coeliac trunks, 31 in the superior mesenteric artery, and 2 in a hepatic or splenic artery) and 46 into renal arteries (24 right and 22 left). The renal artery diameters were 5, 6, 7, and 8 mm in 9, 7, 26, and 4 patients, respectively. Mesenteric arteries were exclusively stented with 9 and 10 mm diameter devices. The median follow-up was 33 months (IQ25 17-IQ75 36). During follow-up, 11 patients died (28%) from non-aneurysm-related causes. The overall patency rates for bridging stents were 98% and 97% at 1 and 2 years, respectively, with a freedom from secondary procedure rate on BeGraft stent grafts of 96% (97/101). All events occurred on stents implanted in renal arteries. CONCLUSION: Early favorable outcomes are confirmed during longer term follow-up. Vigilant surveillance is required.

ACR Appropriateness Criteria® Lower Extremity Arterial Claudication-Imaging Assessment for Revascularization: 2022 Update.

Arterial claudication is a common manifestation of peripheral artery disease. This document focuses on necessary imaging before revascularization for claudication. Appropriate use of ultrasound, invasive arteriography, MR angiography, and CT angiography are discussed. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Automated Image Fusion Guidance during Endovascular Aorto-Iliac Procedures: A Randomized Controlled Pilot Study.

BACKGROUND: The benefits of imaging guidance using a new fully automated fusion process (CYDAR) have been demonstrated during endovascular aortic aneurysm repair, but little is known about its use during aorto-iliac occlusive disease endovascular revascularization. The aim of this study was to evaluate the influence of CYDAR image fusion guidance during endovascular treatment of symptomatic aorto-iliac occlusive lesions, compared with control patients treated using standard 2D fluoroscopy alone. METHODS: This is a single-center randomized controlled pilot study that recruited patients undergoing aorto-iliac endovascular revascularization. RESULTS: Between January 2019 and February 2020, 37 patients with symptomatic aorto-iliac lesions were enrolled: 18 were assigned to the fusion group and 19 to the control group. Patients and lesions characteristics were well balanced between both study groups. The technical success of the procedure was 100% in the Fusion group and 94% in the control group. All radiation-related parameters were lower in the fusion compared to the control group, including: median DAP 18.5 Gy.cm2 vs. 21.8 Gy.cm2; Air Kerma 0.10 Gy vs. 0.12 Gy; fluoroscopy dose 4.2 Gy.cm2 vs. 5.1 Gy.cm2; and number of DSA 7.5 vs. 8. The volume of iodinated contrast used was higher in the fusion group: 41 mL vs. 30 mL. The total procedure time was the same in both groups:60 min vs. 60 min. CONCLUSIONS: The results of this pilot study suggest the use of fusion imaging in endovascular treatment of aorto-iliac disease results in reduction in radiation-related measured parameters with no change in procedure time and higher doses of iodinated contrast used. These results need to be further investigated in a larger, adequately powered study.

Editor's Choice - Long-term Survival and Risk Analysis in 136 Consecutive Patients With Type B Aortic Dissection Presenting to a Single Centre Over an 11 Year Period.

OBJECTIVES: To evaluate, in patients with acute type B aortic dissection, the results of medical and endovascular treatment in a large single centre experience and to investigate the clinical and imaging features on presentation that relate to poor outcome. METHODS: This was a retrospective analysis of prospectively collected clinical and CT imaging data. Consecutive patients (136) with acute type B aortic dissection were included in the study over an 11 year period. The characteristics of patients receiving endovascular (complicated) or medical treatment (uncomplicated) were compared. Kaplan-Meier estimators were used to estimate cumulative overall survival and survival free of aortic events. Factors associated with overall and aortic event free survival were also explored using Cox proportional hazards models. RESULTS: The mean follow up was 51 months (1-132), during which time 33 deaths and 48 aortic events occurred. At one and five years, overall survival was 94.0% and 74.8%, respectively, and freedom from aortic events was 75.6% and 58.7%. There was no difference in all cause survival and aortic event free survival at one and five years between the patients treated endovascularly and those receiving medical treatment alone. Risk analysis for aortic events demonstrated the maximum size of the proximal entry tear, the maximum thoracic aortic diameter, and the thoracic aortic false lumen maximum diameter to have a significant effect on the incidence of aortic events. CONCLUSIONS: Active management of patients with type B aortic dissection results in good long-term survival even in the presence of features traditionally associated with adverse outcomes. All patients require close lifetime surveillance as aortic events continue to occur during follow up even after endografting.

Multimodality Imaging of Thoracic Aortic Diseases in Adults.

In diagnosing and following patients with acute aortic syndromes and thoracic aortic aneurysms, high-quality imaging of the thoracic aorta is indispensable. Mainstay modalities for thoracic aortic imaging are echocardiography, computed tomographic angiography, and magnetic resonance angiography. For any given clinical scenario, the imaging modality and protocol chosen will have a significant impact on sensitivity and specificity for the aortic diagnosis of concern. Imaging can also provide important ancillary information regarding myocardial performance, aortic valve morphology and function, and end-organ perfusion. Surveillance of patients following thoracic aortic surgery with serial imaging studies can identify complications that may require reintervention, and imaging has played an integral role in development of new surgical and interventional methods. Emerging techniques in thoracic aortic imaging include positron emission tomography, which addresses vessel wall inflammation, and 4-dimensional magnetic resonance angiography, which illustrates flow dynamics.

The potential role of IDEAL MRI for identification of lipids and hemorrhage in carotid artery plaques.

Hemorrhage and lipid deposits contribute to instability in atherosclerotic plaques. Unstable carotid artery plaques can lead to cerebral ischemic events. While MRI studies have shown the ability to identify plaque components, the identification of hemorrhage and lipids has proven to be problematic. The purpose of this study was to quantitatively evaluate the potential of the MRI fat/water separation method known as iterative decomposition of water and fat with echo asymmetry and least squares estimation (IDEAL) to complement and improve existing methods for the identification of hemorrhage and lipids in carotid artery plaques. Fifteen asymptomatic subjects with 50-79% stenosis of at least one carotid artery were enrolled. Hemorrhage and lipid components within carotid plaques were identified using previously published criteria based on the multiple contrast-weighted (MCW) method (3D Time-of-Flight (3D-TOF), T1-Weighted (T1W) and T2-Weighted (T2W)). The hemorrhage:muscle, lipid:muscle and intra-plaque lipid:hemorrhage signal intensity ratios (SIR) and contrast to noise ratios (CNR) were measured on MCW and compared to IDEAL black-blood images. No differences were found between any of the MCW methods for any of the SIRs measured. The IDEAL Fat images had higher lipid:muscle and lipid/hemorrhage SIRs (p<0.001) compared to IDEAL Water and all MCW image sequence types. The mean values of IDEAL Fat hemorrhage:muscle SIR and CNR were nearly unity (1.1±0.6) and nearly zero (0.1±1.1), respectively. The IDEAL Water imaging was not significantly different than any of the MCW methods for any of the SIRs or for the hemorrhage:muscle CNR of 3D-TOF, while its CNRs were significantly higher than IDEAL Fat lipid:muscle (p<0.05) and lipid:hemorrhage (p<0.001) and all MCW methods (p<0.001). The addition of IDEAL Water and Fat imaging to the MCW method shows potential to improve the identification of hemorrhage and lipid structures in carotid artery plaques.

Transcatheter Aortic Valve Implantation as a Bailout Procedure for Acute Aortic Valve Regurgitation During Endovascular Arch Repair.

PURPOSE: To report emergent transcatheter aortic valve implantation (TAVI) to treat acute severe aortic regurgitation caused by valve cusp dysfunction following proximal migration of an endograft implanted in the ascending aorta during endovascular arch repair. CASE REPORT: A 65-year-old man had been previously treated with thoracic and fenestrated endografts in a 2-stage procedure for a chronic type B dissection. At 2-year follow-up, aneurysmal evolution of the distal arch led to development of a proximal type Ia endoleak. The patient was deemed unfit for open repair because of severe nonrevascularizable coronary artery disease. A custom-made endograft was designed consisting of a double inner branch arch endograft with a proximal component to reline the ascending aorta to avoid iatrogenic type A dissection. The first component was successfully deployed. However, this device migrated toward the aortic valve when the delivery system of the branch device was advanced through the aortic valve. Aortography and transesophageal echography showed acute aortic regurgitation due to obstruction of the left coronary valve cusp. An emergency bailout TAVI procedure was performed to successfully treat the aortic regurgitation. CONCLUSION: TAVI can be used as a bailout procedure for acute aortic valve dysfunction during endovascular arch or ascending aorta repair.

Total Endovascular Treatment of Aortic Arch Disease Using an Arch Endograft With 3 Inner Branches.

PURPOSE: To report early experience with a new endovascular graft developed for aortic arch aneurysm repair in patients unfit for open surgery. CASE REPORT: Three consecutive men (62, 74, and 69 years old) at high risk for open repair were treated for postdissection aortic arch aneurysms using a custom-made 3 inner branched endovascular graft. The 2 proximal branches are antegrade and perfuse the innominate artery and the left common carotid artery; the third branch is retrograde and perfuses the left subclavian artery. The latter is preloaded with a catheter and wire to aid cannulation. Technical success was achieved in each case. The mean procedure time, fluoroscopy duration, and contrast volume were 180 minutes, 35 minutes, and 145 mL, respectively. The perioperative period was uneventful. All branches were patent on 6-month computed tomography and duplex ultrasound imaging. CONCLUSION: This new patient-specific device allows total endovascular revascularization of the supra-aortic trunks during arch repair. These encouraging results support its more widespread use.

Endovascular Repair of Thoracoabdominal and Arch Aneurysms in Patients with Connective Tissue Disease Using Branched and Fenestrated Devices.

BACKGROUND: Prophylactic open surgery is the standard practice in patients with connective tissue and thoracoabdominal aortic aneurysm (TAAA) and aortic arch disease. Branched and fenestrated devices offer a less invasive alternative but there are concerns regarding the durability of the repair and the effect of the stent graft on the fragile aortic wall. The aim of this study is to evaluate mid-term outcomes of fenestrated and/or branched endografting in patients with connective tissue disease. METHODS: All patients with connective tissue disease who underwent TAAA or arch aneurysm repair using a fenestrated and/or branched endograft in a single, high-volume center between 2004 and 2015 were included. Ruptured aneurysms and acute aortic dissections were excluded from this study, but not chronic aortic dissections. RESULTS: In total, 427 (403 pararenal and TAAAs, and 24 arch aneurysms) endovascular interventions were performed during the study period. Of these, 17 patients (4%) (16 TAAAs, 1 arch) had connective tissue disease. All patients were classified as unfit for open repair. The mean age was 51 ± 8 years. Thirteen patients with TAAA were treated with a fenestrated, 1 with a branched, and 2 with a combined fenestrated/branch device. A double inner branch device was used to treat the arch aneurysm. The technical success rate was 100% with no incidence of early mortality, spinal cord ischemia, stroke, or further dissection. Postoperative deterioration in renal function was seen in 3 patients (18.8%) and no hemodialysis was required. The mean follow-up was 3.4 years (0.3-7.4). Aneurysm sac shrinkage was seen in 35% of patients (6/17) and the sac diameter remained stable in 65% of patients (11/17). No sac or sealing zone enlargement was observed in any of the patients and there were no conversions to open repair. Reintervention was required in 1 patient at 2 years for bilateral renal artery occlusion (successful fibrinolysis). One type II endoleak (lumbar) is under surveillance and 1 type III (left renal stent) sealed spontaneously. One patient died at 2 years after the procedure from nonaortic causes (endocarditis). CONCLUSIONS: The favorable mid-term outcomes in this series that demonstrate fenestrated and/or branched endografting should be considered in patients with connective tissue and TAAA and aortic arch disease, which are considered unfit for open surgery. All patients require close lifetime surveillance at a center specializing in aortic surgery, with sufficient experience in both open and endovascular aortic surgery, so that if endovascular treatment failure occurs it can be recognized early and further treatment offered.

Evidence for and risks of endovascular treatment of asymptomatic acute type B aortic dissection.

Acute aortic dissection is a challenging disease to manage. Type B aortic dissection has traditionally been divided temporally into acute and chronic cases but more recently this classification has been modified to include a sub-acute phase. Computed tomography is the imaging technique used most frequently in diagnosis and management. Active management of blood pressure is essential and should include beta-blockade unless contraindicated. In-hospital outcomes are generally acceptable in patients with medically managed acute uncomplicated type B aortic dissection, with up to 90% of patients surviving to hospital discharge but by 5 years up to 50% of patients are dead with a significant proportion dying from aortic rupture. The aim of endovascular repair is to treat the complications of the dissection, induce aortic remodeling and false lumen thrombosis and it has been shown to result in good long-term outcomes. Stent graft placement however is associated with an incidence of death, stroke, paraplegia and retrograde type A dissection. Some experts now advocate high intensity imaging in the first 14 days to detect development of complications early in the disease course, with planned elective treatment in the subacute phase.