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.

Endovascular Graft Infection by Neisseria meningitidis: A Rare but Fatal Infection.

Endovascular graft infection is a rare but challenging complication that requires a tailored approach to remove the infected graft and restore the arterial circulation combined with long-term antibiotic therapy. We present a case surgically treated with explant of the graft and reconstruction of the thoracoabdominal aorta. Microbiological investigation revealed growth of Neisseria meningitidis, which is extremely rare in this location, and to our knowledge, has not been previously published in the literature.

Endovascular aneurysm repair in a centenarian: case report and systematic literature review.

The prevalence of abdominal aortic aneurysms (AAA) in the nonagenarian and centenarian populations is set to increase. Endovascular aneurysm repair (EVAR) has been shown to be achievable with excellent outcomes in carefully selected nonagenarians. However, experience with centenarians is limited. We report the case of a 100-year-old who presented with a tender 8-cm AAA and successfully underwent EVAR. This report describes the second case of AAA repair in a centenarian in the literature and the first reported EVAR in this demographic. The patient survived for 2 years after the procedure, was free of EVAR or aneurysm-related complications. Furthermore, we present a systematic review of the existing literature and insights pertaining to outcomes in nonagenarians undergoing EVAR.

True aneurysm of the digital artery: a case report and systematic literature review.

Aneurysmal disease can occur in any vessel in the body and occur most commonly the aorta, cerebral and popliteal arteries; however, aneurysms of the digital artery remain a rare presentation. They form an important differential diagnosis in any patient presenting with a mass in the hand. This report presents the case of a 64-year-old man with a true aneurysm of the common palmar digital artery who underwent successful repair, following excision and end to end anastomosis. Only 21 cases of true digital artery aneurysm have been reported; we review the literature pertaining to the diagnosis and management of digital artery aneurysms since they were first described by Baruch et al in 1977.

Nitric oxide manipulation: a therapeutic target for peripheral arterial disease?

Peripheral Arterial Disease (PAD) is a cause of significant morbidity and mortality in the Western world. Risk factor modification and endovascular and surgical revascularisation are the main treatment options at present. However, a significant number of patients still require major amputation. There is evidence that nitric oxide (NO) and its endogenous inhibitor asymmetric dimethylarginine (ADMA) play significant roles in the pathophysiology of PAD. This paper reviews experimental work implicating the ADMA-DDAH-NO pathway in PAD, focussing on both the vascular dysfunction and effects within the ischaemic muscle, and examines the potential of manipulating this pathway as a novel adjunct therapy in PAD.

Potential of Novel EPO Derivatives in Limb Ischemia.

Erythropoietin (EPO) has tissue-protective properties, but it increases the risk of thromboembolism by raising the haemoglobin concentration. New generation of EPO derivatives is tissue protective without the haematopoietic side effects. Preclinical studies have demonstrated their effectiveness and safety. This paper summarizes the development in EPO derivatives with emphasis on their potential use in critical limb ischaemia.

Review of the role of erythropoietin in critical leg ischemia.

There is a need to develop alternative treatment strategies for the 30% of patients with critical leg ischemia (CLI) for whom conventional modes of revascularization fail. The efficacy erythropoietin (EPO) in this regard has been verified in preclinical models. Erythropoietin receptors are expressed in the human skeletal muscle and possibly, upregulated in CLI. Furthermore, EPO induces angiogenesis and prevents apoptosis in the ischemic skeletal muscle. The use of EPO in conjunction with autologous bone marrow cells or gene-induced angiogenesis with vascular endothelial growth factor may be more effective in inducing angiogenesis and protecting the critically ischemic leg than EPO alone. The recently synthesized nonhemopoietic derivatives of EPO (eg, asialo erythropoietin and carbamylated erythropoietin) allow higher doses to be administered to achieve tissue protective effects, without an unwanted increase in hematocrit. This may allow translation of preclinical studies into clinical trials.

Internal herniation of the caecum into the lesser sac: an unusual cause of an acute abdomen (2009: 10b).

Internal hernias are rare, occurring in 0.2-0.9% of autopsy cases. Hernias through the foramen of Winslow are even rarer, occurring in up to 8% of internal hernias. The clinical presentation is variable, making diagnosis difficult, and a delay in diagnosis can result in significant morbidity. As such, early radiological diagnosis is paramount. We report a rare case of caecal herniation through the foramen of Winslow in a 49-year-old female patient in whom the diagnosis was made radiologically and allowed appropriate and prompt management.

Factors affecting long-term survival of tunnelled haemodialysis catheters--a prospective audit of 812 tunnelled catheters.

BACKGROUND: In 2001, in the US, 23% of haemodialysis patients were dialysing through tunnelled venous catheters (TVCs), and in the UK (2006) there were 28% of prevalent patients using catheters. It is unlikely that numbers will significantly decrease. We present the results of a prospective audit of the survival of 812 TVCs placed in 492 patients at our institution over a 6-year period (comprising 212 048 patient catheter days or 7068 patient catheter months of follow-up). Four different designs of catheter were studied: Split-Cath III (Medcomp), HemoSplit (Bard), Tesio twin catheter (Medcomp) and Permcath (Quinton). METHODS: We used Kaplan-Meier survival analysis with log-rank test, to compare the effect of different parameters on catheter survival. The relative importance of significant parameters was determined by Cox regression analysis. RESULTS: We have shown a significant catheter survival advantage of first catheters over second and subsequent insertions, of right internal jugular site over left internal jugular and thereafter over femoral site, and of non-diabetic over diabetic patients. Patient age, sex and operator (physician in ward-based procedure room under ultrasound control or surgeon in operating theatre under fluoroscopic assistance) did not significantly affect survival. The Permcath design demonstrated inferior survival in all but first catheter insertions in catheter-naïve patients. The HemoSplit and Tesio twin catheter designs demonstrated best survival overall. By Cox proportional hazard modelling the design and the position of the TVC seemed to be the most significant independent survival factors. CONCLUSIONS: Clinicians need accurate data regarding catheter survival, mode of insertion and design, to inform practice.