Aggressive treatment of early fistula failure.

BACKGROUND: Fistula failure has been classified as early and late. Early failure refers to those cases in which the arteriovenous (AV) fistula never develops to the point that it can be used or fails within the first 3 months of usage. It has been common practice to abandon these early failures; however, aggressive evaluation and treatment of early fistula failures has been shown to result in the salvage of a large percentage. The two most common causes of the failure seen at this time are juxta-anastomotic stenosis (JAS) and the presence of accessory veins. Both of these can be easily diagnosed by physical examination. This study reports the results of early fistula failure managed aggressively in an attempt at salvage.
METHODS: These studies were conducted in six freestanding outpatient interventional facilities in different regions of the United States. Interventional nephrologists are employed at all of these facilities except one that is operated by an interventional radiologist. Each patient was first evaluated angiographically to identify the anatomy of their AV fistula and detect abnormalities that might be present. Stenotic lesions were then treated with angioplasty and accessory veins thought to be significant were obliterated. All patients were then followed to determine if the fistula was usable for dialysis.
RESULTS: One hundred patients were identified that met the definition of early failure. Venous stenosis was present in 78% of these cases. In 43% of the cases, the lesion was in the JAS location. In 15%, this was the only lesion present. In 24%, it was associated with an accessory vein, in 6% with a proximal stenosis, and in 4% with both. A proximal stenosis lesion was present in the fistula in 36%. In 6%, it was associated with an accessory vein, in 6% with a JAS, and in 4% with both. The definition of arterial anastomosis stenosis was met in 38% of the cases. This was always in association with JAS. In four cases, a stenotic lesion was present in the artery above the anastomosis. An accessory vein was present in 46% of the cases. In 12% of the cases, this was the only lesion present. In 24% of the cases, this anomaly was associated with JAS, in 6% with proximal stenosis, and in 4% with both. Angioplasty was performed to treat venous stenosis in 72% of the cases with a 98% success rate. Angioplasty of the arterial anastomosis was performed in 38 cases with a 100% success rate. Accessory vein obliteration was performed in 46% of the patients with a 100% success rate. The overall complication rate in this series was 4%, of these 3% were minor and 1% were major. It was possible to initiate dialysis using the fistula in 92% of the cases. Actuarial life-table analysis showed that 84% were functional at 3 months, 72% at 6 months, and 68% at 12 months.
CONCLUSION: If correctable pathology is detected in patients with early fistula failure, the incidence of correctable lesions is relatively high and an aggressive therapeutic approach can be expected to have a high yield.