The new arteriovenous fistula: the need for earlier evaluation and intervention.

The National Kidney Foundation's Dialysis Outcomes Quality Initiative recommends an ideal 3- to 4-month arteriovenous fistula (AVF) maturation period prior to cannulation. This recommendation may be misinterpreted by practicing nephrologists to mean that they should wait 3 months before performing a clinical assessment of the AVF. Such a delay in evaluating AVF maturity results in unnecessarily prolonged catheter use in dialysis patients whose ultimately unsatisfactory fistula could already have been diagnosed and modified at a much earlier point. Clinical assessment at 1 month can detect the common etiologies for nonmaturity, including stenosis in the vein adjacent to the anastomosis and accessory vein diversion of flow from the main fistula vein. Duplex ultrasound provides additional information in selected cases. Early evaluation allows for early fistulography for problems and potentially early cannulation for adequately maturing fistulas. Prospective trials of early AVF clinical assessment at 1 month should be performed.