Arteriovenous fistula construction in the thigh with transposed superficial femoral vein: our initial experience.

PURPOSE: The National Kidney Foundation-Dialysis Outcomes Quality Initiative guidelines favor autogenous vein for arteriovenous fistulas (AVFs). This report describes our experience constructing AVFs in the lower extremities of selected patients with the superficial femoral vein (SFV). PATIENTS AND METHODS: This is a retrospective analysis of 25 patients who had AVF construction with SFV from March 1998 to July 2000. In all patients upper extremity access had been exhausted. Eighteen (72%) patients were female, 15 (60%) had diabetes, and 14 (56%) were obese (body mass index > 30 kg/m(2)). The SFV was freed from the supragenicular popliteal level to the profunda femoris vein and divided distally. Eighteen (72%) patients had SFV transposition and distal superficial femoral artery reimplantation; 10 veins were banded to reduce the incidence of postoperative steal syndrome. In seven patients (28%) a composite loop fistula was constructed with a deeply buried 4- to 7-mm polytetrafluoroethylene (PTFE) graft proximally and with superficially transposed SFV distally. One of these seven patients had a PTFE above-knee femoral-popliteal bypass graft with banding of the vein at its takeoff from the distal PTFE graft. RESULTS: Mean follow-up was 9.1 months. One patient died before the fistula could be used. Seven patients (28%) experienced major wound complications. Mean ankle/brachial index before operation was 1.03, and after operation it was 0.81 (paired difference [n = 16] = -0.26.) Mean ankle circumference before operation was 19.5 cm, and after operation it was 20.7 cm (paired difference [n = 17] = +0.87.) Cumulative primary fistula patency at 6 and 12 months was 78% and 73%, respectively. Cumulative secondary fistula patency at 6 and 12 months was 91% and 86%, respectively. There were no fistula infections. One patient eventually had an above-knee amputation after experiencing an acute compartment syndrome. Eight patients required a second operation to alleviate a symptomatic steal syndrome. CONCLUSIONS: The SFV is an excellent conduit for vascular access, whether it is transposed or is part of a composite PTFE-SFV fistula. In this series, fistula infection was nonexistent, thrombosis rates were low, and clinical evidence of venous hypertension was minimal. The major impediment to unrestricted use of SFV in constructing AVFs is a high incidence of clinically significant postoperative ischemia requiring reoperation.

Bypass graft to the midpopliteal artery with a combined anterior and posterior approach.

PURPOSE: The medial supragenicular and infragenicular approaches to the popliteal artery were introduced almost 50 years ago and replaced the posterior approach to the popliteal artery for distal graft implantation. We review a contemporary series of bypass grafts to the midpopliteal artery by use of a combined anterior and posterior approach to evaluate its potential clinical benefits. TECHNIQUE: After the proximal graft anastomosis is constructed, an incision is made in the popliteal fossa to access the midpopliteal artery, the graft is passed into that incision, and all but the popliteal incision is closed. The patient is turned, the midpopliteal artery dissection is completed, and the graft is anastomosed distally. METHODS: Fifty-seven bypass grafts, implanted distally on the midpopliteal artery by this technique over a 13-year period, chosen in preference to an infragenicular bypass graft in selected patients when a supragenicular bypass was not feasible, were assessed in terms of indications for surgery, conduit type, complications, length of postoperative hospitalization, and graft patency. RESULTS: Bypass grafting originated from the axillary artery in two cases, the common iliac artery in one case, and the femoral artery in 54 cases. The procedure was performed in five patients with a popliteal trifurcation anomaly, nine patients with a blind popliteal segment, 20 patients with limited length of autologous vein, and five patients with an above-knee graft infection requiring an alternate path for revascularization. Autologous vein was used in 35 and polytetrafluoroethylene (PTFE) in 19 bypass grafts. Three other patients had a composite sequential femoral-popliteal-tibial bypass graft, with PTFE and autologous vein. Postoperative (30 day) complications include one death (composite sequential), one stroke (PTFE), and one graft thrombosis (saphenous vein). The mean postoperative hospitalization for the last 31 patients was 4.2 +/- 3.7 days. In the autologous vein group, the 1-year primary patency rate was 87%, and the primary assisted patency rate was 94%. In the PTFE group, the 1-year primary patency rate was 72%. Two composite sequential grafts remained patent at 1 year. CONCLUSIONS: Bypass grafting to the midpopliteal artery with a combined anterior and posterior approach offers a safe and effective option to below-knee bypass grafting when an above-knee bypass grafting is not feasible. Compared with the medial infragenicular incision, the posterior incision results in reduced morbidity rates, rapid mobilization, and early hospital discharge.

Homocysteine-associated acute mesenteric artery occlusion treated with thrombectomy and bowel resection.

Elevated plasma homocysteine is an acknowledged risk factor for arteriosclerotic occlusive disease, but little clinical evidence is available regarding its role in acute arterial thrombosis in the absence of an underlying lesion. A 45-year old man presented with an acute abdomen. A magnetic resonance arteriogram (MRA) showed occlusion of the superior mesenteric artery. At exploration, necrotic ileum was resected and the superior mesenteric artery was thrombectomized, restoring normal mesenteric flow. The plasma homocysteine level was 98.8 mmol/L, more than eight times the normal level. No embolic source was identified and an MRA and contrast arteriogram showed no residual occlusive disease in the superior mesenteric artery. Additional studies documented pernicious anemia, which was treated with cobalamin (vitamin B12) injections. This case provides further evidence of an association between hyperhomocysteinemia and acute arterial thrombosis. Hyperhomocysteinemia can result from easily correctible vitamin B12, B6, or dietary folate deficiencies. Plasma homocysteine levels should be determined in young individuals with acute arterial thrombosis whenever a hypercoagulable state is suspected.

Balloon angioplasty, stenting, and role of atherectomy.

Endovascular interventions for the treatment of lower-extremity atherosclerotic disease have undergone a rapid course of development during the past 30 years. Balloon angioplasty is the most widely applied of these techniques and has been shown to yield excellent results, at least in the short and intermediate terms, in appropriately selected patients. The ideal candidate is one with a focal stenotic lesion of the iliac artery; this is also the type of patient in whom placement of an endoluminal stent, whether primarily or as an adjunct to balloon angioplasty, has been shown to be most effective. The initial enthusiasm for transluminal atherectomy of lower-extremity atherosclerotic lesions has met with some disappointing long-term results. It is now used mainly in conjunction with either or both of the above modalities in a select group of patients. Clearly, more controlled studies of all these techniques are needed to better define their exact indications and limitations in treatment of lower-extremity arterial disease.