Introduction. Dialysis associated steal syndrome (DASS) constitutes a serious risk for patients undergoing vascular access operations. We aim to assess the measured volume flow using ultrasound in patients with clinically suspected steal syndrome and determine differences in flow among types of arteriovenous (AV) access. Methods. Patients with permanent hemodialysis access with and without ischemic steal underwent duplex ultrasound (US) exams for the assessment of volume flow and quantitative evidence of hemodynamic steal. Volume flow was measured in the proximal feeding artery. Results. 118 patients underwent US of which 82 (69.5%) had clinical evidence of steal. Women were more likely to develop steal compared to men (chi-squared test P < 0.04). Mean volume flow in patients with steal was 1542 mL/min compared to 1087 mL/min (P < 0.002) in patients without evidence of steal. A significant difference in flow volumes in patients with and without steal was only seen in patients with a brachial-cephalic upper arm AV fistula (AVF) (P < 0.002). When comparing different types of access with steal, brachial-cephalic upper arm AVFs had higher volume flows than the upper extremity AV graft (AVG) group (P = 0.04). Conclusion. In patients with DASS, women were more likely to develop steal syndrome. Significantly higher volume flows were seen with brachial-cephalic upper arm AVF in patients with steal compared to those without. A physiologic basis of this US finding may be present, which warrants further study into the dynamics of flow and its relationship to the underlying peripheral arterial pathology in the development of ischemic steal.

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We have recently treated two patients with complications associated with the use of a covered stent (Bard Fluency) for salvage of an autogenous fistula. Both patients were elderly white females with end stage renal disease requiring dialysis. They had successfully received brachial vein transpositions with elevation and had been on dialysis for two to six months. In both these individuals they had developed small pseudoaneurysms due to repetitive sticks in the same location. They presented with persistent bleeding which was intermittent from the pseudoaneurysms. Interventional techniques were used to place a covered stent in one, and two overlapping stents were placedin the other patient. This treatment was immediately successful. Both patients continued dialysis without incident. Over the course of several months, however it was noticed in both patients that a small scab appeared at the site of the pseudoaneurysm. In both patients these small scabs progressed to complete erosion of the covered metal stent through the skin. There was no bleeding associated with the erosion, just the appearance of the metal stents over the covered prosthetic. A surgical correction was then performed with a wide dissection and undermining the surrounding tissue to have a two layer closure over the exposed segment of the fistula/stent. Dialysis continued uninterrupted. It will require several months to determine if this approach is successful for this problem. Interventional techniques with covered stents have become a mainstay of treatment for isolated arterial bleeding and have been quite successful. It would, therefore, only seem logical that this technology could be applied to arterial bleeding from an autogenous dialysis fistula. Stent placement has been used extensively for areas of stenosis in arteriovenous fistulae and grafts, however the areas are usually deep in the tissues and not in superficial areas. The problems with use of covered stents in these types of situation are twofold. One, when the bleeding has occurred secondary to needle sticks, with the development of a pseudoaneurysm, the area, by definition, is very superficial with limited overlying tissue to help with healing. The other issue which is probably more important is that the anatomy and histology of a vein, even an arterialized vein, is fundamentally different from an artery. They both have a tunica intima, a tunica media and a tunica adventitia but in the artery the walls are thicker and the tunica media is much larger. The thicker walls and tunica media of the arteries allow ingrowth and healing. The vein wall is very thin with less muscle fibers, collagen fibers and elastic fibers and if close to the skin as in both these instances the covered stent will erode through the injured thin walled vein and skin. It would appear from these case reports that an access related pseudoaneurysm of an autogenous fistula might best be served by a combined interventional approach with a surgical approach to help cover the area and bury the vessel/stent in deeper tissu...

There has been a marked shift in treatment modality for advanced femoro-popliteal disease with a lowering of the symptomatic threshold for intervention over 2 decades, likely spurred by the ease of endoluminal interventions. Although peri-procedural and anatomic outcomes for both procedures are equivalent, it appears that open surgery carries a superior long-term clinical efficacy. This superiority is negatively influenced by poor preoperative ambulation status, high modified Cardiac Risk Score, worse presenting symptoms, the occurrence of major adverse cardiovascular events, poor tibial runoff, the absence of hemodynamic success, and occlusion of the original bypass.

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