Target Balloon-Assisted Antegrade and Retrograde Use of Re-Entry Catheters in Complex Chronic Total Occlusions.

Purpose, Retrograde recanalizations have gained increasing recognition in complex arterial occlusive disease. Re-entry devices are a well described adjunct for antegrade recanalizations. We present our experience with target balloon-assisted antegrade and retrograde recanalizations using re-entry devices in challenging chronic total occlusions. MATERIALS AND METHODS: We report data from a retrospective multicenter registry. Eligibility criteria included either antegrade or retrograde use of the OutbackTM or GoBackTM re-entry catheter in combination with a balloon as a target to accomplish wire passage, when conventional antegrade and retrograde recanalization attempts had been unsuccessful. Procedural outcomes included technical success (defined as wire passage though the occlusion and delivery of adjunctive therapy with <30% residual stenosis at final angiogram), safety (periprocedural complications, e.g., bleeding, vessel injury, or occlusion of the artery at the re-entry site, and distal embolizations), and clinical outcome (amputation-free survival and freedom from target lesion revascularization after 12-months follow-up). RESULTS: Thirty-six consecutive patients underwent target balloon-assisted recanalization attempts. Fourteen (39 %) patients had a history of open vascular surgery in the index limb. Fifteen patients were claudications (Rutherford Class 2 or 3, 21 presented with chronic limb threatening limb ischemia (Rutherford Class 4 to 6). The locations of the occlusive lesions were as follows: iliac arteries in 3 cases, femoropopliteal artery in 39 cases, and in below-the-knee arteries in 12 cases. In 15 cases, recanalization was attempted in multilevel occlusions. Retrograde access was attempted in 1 case in the common femoral artery, in the femoropopliteal segment in 10 cases, in below-the-knee arteries in 23 cases, and finally in 2 patients via the brachial artery. In 10 cases, the re-entry devices were inserted via the retrograde access site. Technical success was achieved in 34 (94 %) patients. There were 3 periprocedural complications, none directly related to the target balloon-assisted re-entry maneuver. Amputation-free survival was 87.8 % and freedom from clinically driven target lesion revascularization was 86.6 % after 12-months follow-up. CONCLUSION: Target balloon-assisted use of re-entry devices in chronic total occlusions provides an effective and safe endovascular adjunct, when conventional antegrade and retrograde recanalization attempts have failed.

Deep Vein Thrombosis Exhibits Characteristic Serum and Vein Wall Metabolic Phenotypes in the Inferior Vena Cava Ligation Mouse Model.

OBJECTIVES: Deep vein thrombosis (DVT) is a major health problem, responsible for significant morbidity and mortality. The identification of a simple and effective diagnostic biomarker of DVT remains a challenge. Metabolomics have recently emerged as a new powerful scientific tool to characterise metabolic phenotypes of complex diseases and investigate small molecules in biofluids. The aim of the study was to identify the blood and vein wall metabolomic signature of DVT in a murine experimental model. METHODS: An established inferior vena cava ligation mouse model of DVT (n=10) was used and compared with sham surgery controls (n=10). Comprehensive untargeted metabolic profiling of serum and vein wall extracts was undertaken using liquid chromatography coupled mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR) spectroscopy. RESULTS: Multivariate and univariate statistical analysis demonstrated a differential metabolic profile when comparing DVT mice and control animals. Serum from DVT mice was characterised by differential concentrations of adenosine (decreased in DVT mice 9.6 fold), adenine (decreased 10.6 fold), and tricyclic acid cycle (TCA) intermediates, including citrate, succinate, and fumarate (1.5, 2.3, and 2.8 fold decreases, respectively). l-carnitine was found to be of greater abundance in the serum of DVT animals (67.0 fold change). A number of lipid moiety classes, including sphingomyelins, phosphatidylcholines, and triglycerides, were differentially abundant. Several metabolites were found in vein wall, including acetylcarnitine (increased in DVT mice 1.9 fold), adenosine (increased 2.2 fold), and ceramide (increased 2.7 fold). Correlation analysis illustrated the biochemical relationships between assigned metabolites, with the discriminatory molecules being highly correlated with each other, in both serum and vein wall. CONCLUSIONS: The present findings demonstrate that metabolic dysregulations in DVT centre on energy metabolism, sphingolipid, and adenosine metabolism, representing a DVT specific metabolite signature in a murine experimental model.

A Temporal and Spatial Analysis Approach to Automated Segmentation of Microbubble Signals in Contrast-Enhanced Ultrasound Images: Application to Quantification of Active Vascular Density in Human Lower Limbs.

Contrast-enhanced ultrasound (CEUS) using microbubble contrast agents has shown great promise in visualising and quantifying active vascular density. Most existing approaches for vascular density quantification using CEUS are calculated based on image intensity and are susceptible to confounding factors and imaging artefact. Poor reproducibility is a key challenge to clinical translation. In this study, a new automated temporal and spatial signal analysis approach is developed for reproducible microbubble segmentation and quantification of contrast enhancement in human lower limbs. The approach is evaluated in vitro on phantoms and in vivo in lower limbs of healthy volunteers before and after physical exercise. In this approach, vascular density is quantified based on the relative areas microbubbles occupy instead of their image intensity. Temporal features of the CEUS image sequences are used to identify pixels that contain microbubble signals. A microbubble track density (MTD) measure, the ratio of the segmented microbubble area to the whole tissue area, is calculated as a surrogate for active capillary density. In vitro results reveal a good correlation (r2 = 0.89) between the calculated MTD measure and the known bubble concentration. For in vivo results, a significant increase (129% in average) in the MTD measure is found in lower limbs of healthy volunteers after exercise, with excellent repeatability over a series of days (intra-class correlation coefficient = 0.96). This compares to the existing state-of-the-art approach of destruction and replenishment analysis on the same patients (intra-class correlation coefficient ≤0.78). The proposed new approach shows great potential as an accurate and highly reproducible clinical tool for quantification of active vascular density.

Simulated Wound Assessment Using Digital Planimetry versus Three-Dimensional Cameras: Implications for Clinical Assessment.

BACKGROUND: Clinical management of wounds can benefit from objective measures of response to treatment. Wound surface area and volume are objective measures of wound healing. Using a synthetic wound model, we compare the accuracy and reproducibility of 2 commercially available 3-dimensional (3D) cameras against planimetry and water displacement. METHODS: Twelve ulcers of various sizes and colors were reproduced in modeling clay and cured. Five naive observers used digital planimetry, water displacement, Eykona camera (Fuel 3D, UK), and Silhouette camera (ARANZ, New Zealand) to measure the wounds. RESULTS: When compared with traditional planimetry, wound surface area measurement with Eykona and Silhouette tended to underestimate wounds by 1.7% and 3.7%, respectively. Spearman correlation coefficients were 0.94 (Eykona) and 0.92 (Silhouette). Intraclass correlations for planimetry and the 2 cameras were all 1. Eykona and Silhouette tended to underestimate wound volumes when compared with water displacement by 58% and 23%, respectively. Spearman correlation coefficients were 0.92 (Eykona) and 0.72 (Silhouette). Intraclass correlations for water displacement and the two cameras were all 1. DISCUSSION: Serial accurate objective area measurements are feasible as part of ongoing clinical assessment of wounds. 3D cameras are reliable but have not shown superior accuracy to manual planimetry, and financial concerns and IT integration may limit general clinical usage. Volume measurements of wounds are practicable as part of clinical care.

A multi-centre randomised controlled trial comparing radiofrequency and mechanical occlusion chemically assisted ablation of varicose veins - Final results of the Venefit versus Clarivein for varicose veins trial.

Background Endovenous thermal ablation has revolutionised varicose vein treatment. New non-thermal techniques such as mechanical occlusion chemically assisted endovenous ablation (MOCA) allow treatment of entire trunks with single anaesthetic injections. Previous non-randomised work has shown reduced pain post-operatively with MOCA. This study presents a multi-centre randomised controlled trial assessing the difference in pain during truncal ablation using MOCA and radiofrequency endovenous ablation (RFA) with six months' follow-up. Methods Patients undergoing local anaesthetic endovenous ablation for primary varicose veins were randomised to either MOCA or RFA. Pain scores using Visual Analogue Scale and number scale (0-10) during truncal ablation were recorded. Adjunctive procedures were completed subsequently. Pain after phlebectomy was not assessed. Patients were reviewed at one and six months with clinical scores, quality of life scores and duplex ultrasound assessment of the treated leg. Results A total of 170 patients were recruited over a 21-month period from 240 screened. Patients in the MOCA group experienced significantly less maximum pain during the procedure by Visual Analogue Scale (MOCA median 15 mm (interquartile range 7-36 mm) versus RFA 34 mm (interquartile range 16-53 mm), p = 0.003) and number scale (MOCA median 3 (interquartile range 1-5) versus RFA 4 mm (interquartile range 3-6.5), p = 0.002). ' Average' pain scores were also significantly less in the MOCA group; 74% underwent simultaneous phlebectomy. Occlusion rates, clinical severity scores, disease specific and generic quality of life scores were similar between groups at one and six months. There were two deep vein thromboses, one in each group. Conclusion Pain secondary to truncal ablation is less painful with MOCA than RFA with similar short-term technical, quality of life and safety outcomes.

The role of cost-effectiveness for vascular surgery service provision in the United Kingdom.

OBJECTIVE: The cost of health care is increasingly becoming an international issue, with many health care systems requiring evaluation of cost when agreeing to fund health care. In the United Kingdom (UK), for example, the National Institute for Health and Care Excellence highlights the importance of using cost-effectiveness analyses to facilitate the effective use of resources. This study evaluates the use of cost-effectiveness analyses and the provision of vascular surgery. METHODS: A systematic review of published literature was performed. UK-based studies assessing cost-effectiveness or cost-utility of superficial venous interventions, abdominal aortic aneurysm (AAA) repair, and carotid endarterectomy (CEA) were included. All included studies were quality assessed to determine the overall strength of UK economic evidence for each intervention. RESULTS: Four superficial venous, six AAA, and two CEA studies met the inclusion criteria. After quality assessment, the UK evidence supporting the cost-effectiveness of superficial venous intervention was graded strong. The economic evidence for asymptomatic and symptomatic CEA was graded limited and insufficient, respectively, owing to a paucity of UK literature in this field. There was strong UK economic evidence affirming that endovascular aneurysm repair (EVAR) is unlikely to be a cost-effective alternative to open repair. CONCLUSIONS: There is strong economic evidence for symptomatic superficial venous intervention. However, funding for varicose vein treatments remains controversial. Future economic analyses are required for symptomatic and asymptomatic CEA to better advise national policy. Despite strong economic evidence, current UK guidance is for EVAR over open repair in the elective setting, with the majority of elective AAA repairs being EVAR.

Inferior vena cava filters for prevention of venous thromboembolism in obese patients undergoing bariatric surgery: a systematic review.

OBJECTIVE: The use of inferior vena cava (IVC) filters for prevention of venous thromboembolism (VTE) in bariatric surgery is a contentious issue. We aim to review the evidence for the use of IVC filters in bariatric surgical patients, describe trends in practice, and discuss challenges in developing evidence-based guidelines. BACKGROUND: The incidence of VTE in modern bariatric procedures with traditional methods of thromboprophylaxis, such as sequential calf compression devices and perioperative low molecular weight heparin, is approximately 2%. METHODS: A systematic review of the literature was conducted according to PRISMA guidelines. We searched Medline up until July 2013 with the terms "bariatric filter" and "gastric bypass filter." Two investigators independently screened search results according to an agreed list of eligibility criteria. RESULTS: Eighteen studies were included. There were no randomized controlled trials. Data from controlled cohort studies suggest that those who undergo IVC filter insertion preoperatively may be at higher risk of developing deep vein thrombosis (DVT) and pulmonary embolism (PE). A small cohort of patients with multiple risk factors for VTE benefitted from reduced PE-related mortality after preoperative IVC filter insertion. Data from 12 case series reporting VTE outcomes from a total of 497 patients who underwent preoperative IVC filter insertion demonstrated DVT rates of 0% to 20.8% and PE rates ranging from 0% to 6.4%. CONCLUSIONS: Published data reporting the safety and efficacy of IVC filter use in bariatric surgical patients is highly heterogeneous. There is no evidence to suggest that the potential benefits of IVC filters outweigh the significant risks of therapy.

The use of functional imaging in the diagnosis of carotid patch infection.

Carotid patch infection following carotid patch angioplasty is a rare but serious complication. Accurate diagnosis is vital yet currently ill-defined. We present the use of computed tomography positron emission tomography and leucocyte radioisotope scintigraphy and highlight their potential role in the diagnosis of equivocal carotid patch infection.

Venous injuries in pediatric trauma: Systematic review of injuries and management.

BACKGROUND: Diagnosis of vascular injury in pediatric trauma is challenging as clinical signs may be masked by physiologic compensation. We aimed to (1) investigate the prevalence of noniatrogenic pediatric venous injuries, (2) discuss options in management of traumatic venous injury, and (3) investigate mortality from venous injury in pediatric trauma. Our objective was to provide the practicing clinician with a summary of the published literature and to develop an evidence-based guide to the diagnosis and management of traumatic venous injuries in children. METHODS: A systematic review of published literature (PubMed) describing noniatrogenic traumatic venous injury in the pediatric population (<17 years) was performed according to PRISMA [Preferred Reporting Items for Systematic Reviews and Meta-Analyses] guidelines. Data were retrieved systematically under the following headings: Study Design, Population Demographics (dates of recruitment, mean age, mechanism of injury), Diagnostic Approach, Vessel Injured, Management (operative technique), and Mortality. RESULTS: Thirteen articles were included in this systematic review. In total, 508 noniatrogenic traumatic venous injuries were reported in children between the year 1957 and present day. Mechanisms of injury included blunt trauma from seat belt-related injury and fall from height or penetrating trauma from gunshot and foreign object. Injury to the inferior vena cava was most frequently reported, followed by femoral vein and internal jugular injuries. Primary repair was the most frequently reported technique for surgical repair (38%), followed by ligation (25%) and end-to-end anastomosis (15%). Mortality in pediatric trauma patients who had venous injury was reported as 0% to 67% in published series, highest in the series in which the most frequently reported injury was of the inferior vena cava. CONCLUSION: Traumatic venous injury in the pediatric population is uncommon but may be associated with significant morbidity and mortality. Intra-abdominal venous injuries are associated with high mortality from exsanguination. Early diagnosis and intervention are therefore essential in such cases. LEVEL OF EVIDENCE: Systematic review, level IV.

The Future of Phlebology in Europe.

BACKGROUND: Worldwide superficial and deep venous diseases are common and associated with significant individual and socioeconomic morbidity. Increasing burden of venous disease requires Phlebology to define itself as an independent specialty representing not only patients but the multidisciplinary physicians involved in venous care. METHODS & RESULTS: In this article the scope of venous disease in Europe and subsequent future governance for treatment in the region is discussed. Superficial venous disease is common with 26.9-68.6% of European populations reported to have C2-C6 disease according to the CEAP (Clinical severity, Aetiology, Anatomy and Pathophysiology) scoring system. However, a significant disparity is observed in the treatment of superficial venous disease across Europe. Post thrombotic syndrome (PTS) after deep vein thrombosis (DVT) contributes to the increasing burden of deep venous disease. Aggressive thrombus removal for acute ileofemoral DVT provides a cost-effective 14.4% risk reduction in the development of PTS. Additionally, deep venous lesions requiring endovascular intervention are being increasingly performed to prevent recurrent thrombosis. The European College of Phlebology (ECoP) has been formed to provide a responsible body for the care of the European patient with venous disease. The role of the ECoP includes unifying European member states through standardised guideline production, identification of research strategy and provision of training and accreditation of physicians. CONCLUSION: Creation of a European venous disease specific speciality will provide a patient centred approach through understanding of the impact of disease in the region and delivery of high quality diagnostics and treatment from an appropriately certified Phlebologist.

Periprocedural outcomes after surgical revascularization and stenting for postradiotherapy carotid stenosis.

BACKGROUND: Treatment of head and neck malignancy commonly involves radiotherapy, which is associated with the development of carotid artery stenosis. There is little evidence to guide clinicians on how to intervene in significant postradiotherapy carotid stenosis. This systematic review collated data pertaining to perioperative outcomes of carotid artery surgery and carotid stenting in postradiotherapy carotid stenosis to aid the clinical decision-making process. METHODS: A systematic review of the literature, adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2009 guidelines, was performed. We screened 575 articles related to carotid artery surgery or stenting in postradiotherapy carotid stenosis, from which 21 studies were included for quantitative analysis. The primary outcome was stroke or death ≤ 30 days of the procedure. Secondary outcomes included cranial nerve injury, restenosis, stroke, and death at >30 days. RESULTS: Nine publications recorded 211 surgical procedures in 179 patients. In symptomatic patients, the 30-day mortality rate was 2.6% and the stroke or death rate was 2.7%. In asymptomatic patients, the 30-day mortality rate was 0% and the stroke or death rate was 1.1%. Permanent cranial nerve palsy was experienced by 0.6% of patients. Twelve publications recorded 510 carotid artery stenting procedures in 482 patients. In symptomatic patients, the 30-day mortality rate was 5.1%, and the stroke or death rate was 5.1%. In asymptomatic patients, the 30-day mortality rate was 1.4%, and the stroke or death rate was 2.1%. There was no statistically significant difference in 30-day stroke or death rate between surgical revascularization and carotid artery stenting in all (odds ratio [OR], 0.54; 95% confidence interval [CI] 0.17-1.70; P = .43), symptomatic (OR, 0.52; 95% CI, 0.14-1.98; P = .38), or asymptomatic patients (OR, 0.55; 95% CI, 0.06-5.42; P = .99). CONCLUSIONS: The published outcomes from high-volume centers demonstrate that surgical revascularization and stenting are both technically feasible in postradiotherapy carotid stenosis and have similar safety profiles to nonirradiated necks. Radiation should therefore not be considered a contraindication to surgical intervention.

A rare case of adult primary jejunal volvulus.

Jejunal volvulus is a rare and life threatening presentation of intestinal ischaemia. Clinical features, laboratory investigations and plain abdominal films are non-specific and so computed tomography (CT) scanning is useful in reaching a timely diagnosis. Rapid recourse to surgical intervention is typical and life saving. We report a rare case of primary jejunal volvulus which, after diagnosis on emergency CT scanning, was successfully treated by laparotomy and resection of infarcted bowel.