Active clinical trials for "Arteriovenous Fistula"

The aim of this study is to provide an overview of the possible applications of DUS during the maturation and postoperative follow-up of vascular access, with particular emphasis to establish a relationship between doppler Ultrasound parameters including: Flow volume. Outflow vein diameter. Outflow vein depth. Resistive index.

The transplant is the definitive treatment of renal insufficiency, in our days. While waiting for it, the arteriovenous fistula surgery is standard procedure.

This study is designed to identify novel predictors of vascular access success or failure in chronic kidney disease patients. Despite efforts to improve placement of arteriovenous fistula (AVF) the primary failure rates are reported as high as 20-50%, but standard tools like ultrasound cannot inform the clinician sufficiently to accurately predict success or failure. The aim of this study is to perform enhanced assessments of arterial health preoperatively and correlate these measurements with vascular lesions (microscopic tissue changes and monocyte infiltration) and early AVF outcome. Activation of monocytes in uremia condition is responsible for endothelium dysfunction, intimal hyperplasia and atherosclerosis. The investigators expect that stiff arteries caused by monocyte dysfunction refer to the poor distensability and probably longer maturation time.

The incidence and prevalence of end-stage renal disease (ESRD) in Taiwan are both the highest worldwide from 2001 to 2008. In Taiwan, more than 90% of the ESRD patients are hemodialysis patients. Either arteriovenous fistula (AVF) or arteriovenous graft (AV graft) is essential for the vascular access of these patients. However, frequent AVF stenosis or thrombosis occurs in 10-30% hemodialytic patients, and the rates are even higher, around 30-70%, in those who has a past history of AVF/AV graft stenosis. Therefore, early detection of AVF stenosis is essential in caring for these hemodialysis patients in terms of medical economics and psychological impact. Unfortunately, angiographic study is expensive and invasive and needs contrast medium injection. The diagnostic accuracy of color duplex ultrasound in AVF stenosis remains satisfactory, but it is not always available when decreased AVF flow or an acute thrombotic event occurs. Continuous AVF/ AV graft flow monitoring by patient himself is a better option in terms of long-term care. Previous study indicated that stethoscope waveform analysis could be used as an alternative to diagnosis of vascular stenosis. Therefore, we aim to investigate AVF/ AV graft stenosis by using the electronic stethoscope (3M Littmann) for AVF sound recording, followed by software analysis by using waveform decomposition, principle component analysis (PCA) and sequential forward selection algorithm [xx]. Our study results will provide a new diagnostic option, which is low cost, non-invasive and self-monitoring, of AVF stenosis in ESRD patients.

In this case, we report a case of atresia syndrome (LIS), a serious neurological disease caused by pulmonary arteriovenous fistula (PAVM). We present a previously healthy middle-aged woman who developed atresia syndrome after severe pontine infarction due to basilar artery occlusion due to undiagnosed arteriovenous malformation. This report reviewed the medical history, post-admission examination and related literature, and concluded that PAVM should be considered as the cause of implicit stroke, especially in young patients with right-to-left shunt, and should be actively treated.