A multicenter randomized controlled trial indicates that paclitaxel-coated balloons provide no benefit for arteriovenous fistulas.

The role of paclitaxel-coated balloons has been established in the coronary and peripheral arterial circulations with recent interest in the use of paclitaxel-coated balloons to improve patency rates following angioplasty of arteriovenous fistulas. To assess the efficacy of paclitaxel-coated angioplasty balloons to prolong the survival time of target lesion primary patency in arteriovenous fistulas, we designed an investigator-led multi-center randomized controlled trial with follow up time variable for a minimum of one year. Patients with an arteriovenous fistula who were undergoing an angioplasty for a clinical indication were included but patients with one or more lesions outside the treatment segment were excluded. Following successful treatment with a high-pressure balloon, 212 patients were randomized. In the intervention arm, the second component was insertion of a paclitaxel-coated balloon. In the control arm, an identical procedure was followed, but using a standard balloon. The primary endpoint was time to loss of clinically driven target lesion primary patency. Primary analysis showed no significant evidence for a difference in time to end of target lesion primary patency between groups: hazard ratio 1.18 with a 95% confidence interval of 0.78 to 1.79. There were no significant differences for any secondary outcomes, including patency outcomes and adverse events. Thus, our study demonstrated no evidence that paclitaxel-coated balloons provide benefit, following standard care high-pressure balloon angioplasty, in the treatment of arteriovenous fistulas. Hence, in view of the benefit suggested by other trials, the role of paclitaxel-coated angioplasty balloons remains uncertain.

Ultrasound appearances and histological correlation of native arteriovenous fistula stenoses - A retrospective case series.

The pathophysiology of haemodialysis arteriovenous fistulae (AVF) stenoses is not fully understood. The aim of this study was to perform histology assessment of stenoses in native AVF and compare and correlate the findings between ultrasound and histology. Intimal medial thickness (IMT) was measured on ultrasound where there was measurable neointimal hyperplasia at the site of stenosis and percentage intimal thickening calculated. Ultrasound findings were then compared with histology analysis of AVF stenoses in nine patients. In this small sample, different sonographic appearances and histology were demonstrated. Ultrasound demonstrated stenoses with neointimal hyperplasia and those with no measurable neointimal hyperplasia. Percentage intimal thickening was between 0% and 100%. The histology of the de novo stenoses (where no previous radiological or surgical procedure was performed) demonstrated stenoses with neointimal hyperplasia, no neointimal hyperplasia and neointimal hyperplasia and fibrosis. The histology findings after percutaneous angioplasty (PTA) demonstrated stenoses with neointimal hyperplasia and fibrosis and a stenosis with an acute inflammatory reaction. The findings in this small sample demonstrated that AVF stenoses are not a uniform group as demonstrated by different sonographic and corresponding appearances at histology. Ultrasound appearances of neointimal hyperplasia appear to correlate with neointimal hyperplasia on histology. These findings warrant further investigation and may have implications for treatment strategies.

Acute gastrointestinal bleeding: CT angiography with multi-planar reformatting.

Acute gastrointestinal bleeding is a common medical emergency, which carries a significant mortality. CT Angiography is an important non-invasive diagnostic tool, which can be used to plan subsequent endovascular or surgical management. The cases presented demonstrate that a meticulous and systematic approach to image interpretation is necessary, in particular, to detect focal sites of contrast extravasation and small pseudoaneurysms.

Profile of the Ovation ALTO abdominal stent graft for the treatment of abdominal aortic aneurysms: overview of its safety and efficacy.

INTRODUCTION: The Ovation ALTO is the next generation aortic stent graft from Endologix for the treatment of infra-renal abdominal aortic aneurysms. The device uses polymer-injected rings to create a proximal seal at the aneurysm neck. AREAS COVERED: Results from the first clinical study of the ALTO graft are analyzed and the potential benefits of the graft in minimizing post-treatment aneurysmal neck dilation discussed. The implications of the ALTO's Instructions-For-Use (IFU) and low-profile delivery system are also reviewed. EXPERT OPINION: The re-positioning of the sealing rings higher on the graft and an integrated compliant balloon are the most significant improvements on the Ovation iX, facilitating accurate placement of the proximal sealing ring and prompt balloon dilation of the polymer rings. The expansion the IFU to include neck lengths of ≥7 mm will mean more patients are eligible for infra-renal EVAR within IFU with the ALTO device. The published data on the device to date is limited. With over 1000 implants worldwide we would hope for more published data to become available. If this demonstrates similar mid-term results to that seen with the Ovation iX in arguably more hostile neck anatomy, then the Ovation ALTO is likely to be more widely used.

Balloon assisted, ultrasound guided percutaneous thrombin injection of a large radial artery pseudoaneurysm using a trans-venous approach via an Ipsilateral Arteriovenous Fistula.

BACKGROUND: Pseudoaneurysm formation is known to complicate arteriovenous haemodialysis access. Ultrasound guided thrombin injection is a recognised treatment option, but is not possible in pseudoaneurysms with no measurable neck. Balloon assisted techniques have been described in such cases, which transiently obstruct flow out of the pseudoaneurysm and thereby prevent non-target embolization during ultrasound guided percutaneous thrombin injection. We describe a balloon assisted technique for the treatment of a radial artery pseudoaneurysm, via retrograde access from the draining cephalic vein of an arteriovenous fistula. METHOD: A 61-year-old male with a radio-cephalic fistula was found on duplex ultrasound to have a large radial artery pseudoaneurysm with no measurable neck, as well as a juxta-anastomotic cephalic vein stenosis. Endovascular treatment was selected over open surgery. Retrograde cephalic venous access was established, which allowed for concurrent treatment of both the venous stenosis and the arterial pseudoaneurysm. After balloon dilation of the juxta-anastomotic stenosis, a percutaneous transluminal angioplasty balloon catheter was advanced across the arteriovenous anastomosis and inflated across the neck of the radial artery pseudoaneurysm, to transiently obstruct blood flow. This allowed for safe injection of thrombin into the pseudoaneurysm by direct ultrasound guided sac puncture; thereby achieving thrombosis. CONCLUSIONS: Balloon assisted ultrasound guided thrombin injection is an endovascular treatment option that can obviate the need for open surgery in cases involving pseudoaneurysms with no measurable neck. The technique described allowed both concurrent treatment of a juxta-anastomotic venous stenosis and treatment of an arterial pseudoaneurysm from a single venous puncture. This technique avoided arterial access and its inherent complications.

A single-centre, retrospective analysis of mortality over 80 months comparing paclitaxel-coated balloon versus standard balloon angioplasty in the treatment of dysfunctional arteriovenous access.

AIM: Percutaneous transluminal angioplasty (PTA) is a standard treatment for arteriovenous fistula (AVF) stenosis to preserve haemodialysis vascular access, promoting improved dialysis adequacy and better outcomes for those dependent on renal replacement therapy. Drug coated balloons (DCB) may help reduce the rate of neointimal hyperplasia and recurrent stenosis, but their use in femoropopliteal angioplasty has been associated with increased mortality at 2 and 5 year follow-up. This study aims to address the long-term safety of PTA for AVF stenosis with clinical correlation to participant co-morbidity and mortality. METHODS: All patients undergoing PTA for AVF stenosis at a single centre between 2013 and 2017 were identified and grouped according to the use of DCB versus standard balloon angioplasty. All data was anonymised and correlated to verify independent predictors of mortality. RESULTS: 481 (400 standard balloon; 81 DCB) procedures were performed in 313 patients (250 standard balloon; 63 DCB). Follow-up at 80 months did not show any difference in mortality (p = 0.546). Multivariate analysis identified time on dialysis (p < 0.001), age (p = 0.001) and Charlson comorbidity index (p = 0.02) as independent predictors of mortality. CONCLUSIONS: In this study, mortality was not associated with the use of DCBs, but was related to established factors of dialysis longevity, age and comorbidity.

A UK Expert Consensus Approach for Managing Symptomatic Arteriovenous Fistula (AVF) Stenosis in Haemodialysis Patients.

PURPOSE: Stenoses in mature arteriovenous fistulas (AVFs) are common and can negatively impact on the quality of haemodialysis, the longevity of the AVF and lead to debilitating symptoms. Multiple treatment options exist; however, management can vary between different centres. We aimed to establish multidisciplinary consensus on the optimal stepwise application of interventions based on evidence and consensus. METHODS: A modified Delphi process was conducted with 13 participants from hospitals across the UK, all of whom have high-volume dialysis access practice. RESULTS: The usual intervention to rectify de novo stenoses of mature AVFs is fistuloplasty, although surgery for inflow segment stenoses is also clinically acceptable. Appropriate first-line interventions include plain old balloon angioplasty or high-pressure balloon angioplasty; if these fail during the fistuloplasty, consider upsizing the balloon, prolonged balloon inflation or using alternative interventions, such as cutting or scoring balloons and ultra-high-pressure balloons. Alternative or subsequent interventions vary by anatomical site and may require additional multidisciplinary team input. For a stenoses recurring between 3 and 12 months, it is appropriate to consider interventions used de novo, but with a lower threshold for using drug-coated balloons (DCBs) in all regions and for using stent grafts in all regions but inflow segment. Recurrence after 12 months should be treated as a de novo lesion, with DCBs considered if they have been used successfully during previous interventions. CONCLUSIONS: These recommendations aim to provide a practical guide to multidisciplinary teams in order to optimise the use of multiple interventions for rectifying AVF stenoses and provide unified evidence-based practice guidelines.

Paclitaxel-coated balloon fistuloplasty versus plain balloon fistuloplasty only to preserve the patency of arteriovenous fistulae used for haemodialysis (PAVE): study protocol for a randomised controlled trial.

BACKGROUND: The initial therapy for a stenosis in an arteriovenous fistula used for haemodialysis is radiological balloon dilatation or angioplasty. The benefit of angioplasty is often short-lived, intervention-free survival is reported to be 40-50 % at 1 year. Previous small studies and observational data suggest that paclitaxel-coated balloons may be of benefit in improving outcomes after fistuloplasty of stenotic arteriovenous fistulae. METHODS/DESIGN: We have designed a multicentre, double-blind randomised controlled trial to test the superiority of paclitaxel-coated balloons for preventing restenosis after fistuloplasty in patients with a native arteriovenous fistula. Two hundred and eleven patients will be followed up for a minimum of 1 year. Inclusion criteria include a clinical indication for a fistuloplasty, an access circuit that is free of synthetic graft material or stents, and a residual stenosis of 30 % or less after plain balloon fistuloplasty. Exclusion criteria include a synchronous venous lesion in the same access circuit, location of the stenosis central to the thoracic inlet or a thrombosed access circuit at the time of treatment. The primary endpoint is time to end of target lesion primary patency. This is defined as a clinically-driven radiological or surgical re-intervention at the treatment segment, thrombosis that includes the treatment segment, or abandonment of the access circuit due to an inability to re-treat the treatment segment. Secondary endpoints include angiographic late lumen loss, time to end of access circuit cumulative patency, the total number of interventions, and quality of life. The trial is funded by the National Institute for Health Research. DISCUSSION: We anticipate that this trial will provide rigorous data that will determine the efficacy of additional paclitaxel-coated balloon fistuloplasty versus plain balloon fistuloplasty only to preserve the patency of arteriovenous fistulae used for haemodialysis. TRIAL REGISTRATION: ISRCTN14284759 . Registered on 28 October 2015.

The role of interventional radiology in the treatment of hepatocellular carcinoma.

The incidence of hepatocellular carcinoma (HCC) in the UK is increasing. The role of interventional radiology in the treatment of HCC is well established. We discuss the minimally invasive treatment options that are available. It is important that procedures are undertaken in and postprocedure imaging is reviewed by centers with accredited hepatobiliary units. This is when the best outcomes are achieved. Advances in tumor biology and in technology will continue to expand the role of interventional radiology in the treatment of HCC in the future.

A case for varicella vaccination in the immunosuppressed.

A middle-aged man with long-standing Crohn disease maintained in remission on low-dose immunosuppression presented with abdominal pain. Over the following few days he developed a vesicular rash, became dyspnoeic, confused and had two seizures. Despite high-dose intravenous aciclovir, he died. Disseminated varicella zoster virus, the cause of his death, could potentially have been prevented had he received varicella vaccination at an earlier stage.