Swing point stenosis

Abstract

The most common complication associated with a dialysis vascular access is venous stenosis. A subcategory of this complication is referred to as swing point stenosis. While venous stenosis in general is problematic, this subcategory of lesions is even more so. Swing point lesions develop where the vein that constitutes the arteriovenous fistula (AVF) or its drainage makes a sharp, curved angle. Three swing point lesions have been characterized-(1) juxta-anastomotic stenosis (JAS) seen primarily in association with the radial-cephalic AVF (2) stenosis which develops at the angle of transposition (BATS) in a brachial-basilic AVF, and (3) cephalic arch stenosis (CAS) seen primarily in association with a brachial cephalic AVF. Each of these lesions represents the most common form of stenosis seen in the access with which they are typically associated. JAS is the most common cause of AVF failure to mature and is very important in the salvage of these accesses. Very few studies specifically related to BATS have been published. CAS is the most problematic of the three lesions because of its resistance to treatment, frequency of recurrence and an increased incidence of complications with standard angioplasty treatment. Multiple treatment modalities are available and have been used. However, the pathophysiology of this lesion is very closely related to an increased blood flow rate. For this reason, it is recommended that all patients with CAS have the blood flow rate assessed and used as a guide for treatment.