Duplex scanning-derived access volume flow: novel predictor of success following endovascular repair of failing or nonmaturing arteriovenous fistulae for hemodialysis.

The objective of this study was to evaluate the feasibility of duplex scanning-derived access volume flow (DAVQ) to predict the success or failure of arteriovenous fistulae (AVF) after interventions. Eighty-eight DAVQ measurements were available for 60 AVF in 59 patients. In 25 cases, physical examination findings or inadequate dialysis suggested failing (11) or nonmaturing (14) AVF. Outflow stenoses (1-4; mean 1.2 +/- 0.8) were confirmed by contrast fistulograms in 23 cases (17 peripheral; 6 central). These 23 cases underwent successful endovascular repair (17 balloon angioplasty; 6 stents) and had pre- and postintervention DAVQ measurements within 2 weeks of the procedure. Each was measured three times in a nontortuous venous segment with laminar flow, and mean values were used for comparison. The overall mean DAVQ for 65 functioning AVF was 1,199 +/- 485 mL/min, whereas it was 652 +/- 438 mL/min (range 150-1,840 mL/min) for the remaining 23 failing or nonmaturing cases (p < .0001). Postintervention, the latter values changed to 867 +/- 517 mL/min (range 257-2,020 mL/min), with a p < .13. Of these, 11 were still nonfunctional after endovascular procedures and had a mean DAVQ of 404 +/- 111 mL/min (range 257-652 mL/min). The remaining 12 cases had a mean DAVQ of 1,280 +/- 382 mL/min (range 762-2,020 mL/min) and were functional and usable for at least 6 months of follow-up (p < .0001). It is interesting to note that none of the AVF cases with postintervention DAVQ < 700 mL/min became functional and usable, whereas all cases with a higher DAVQ underwent successful hemodialysis treatments. This early experience suggests that DAVQ can be used to predict the success or failure of an AVF following endovascular procedures. To our knowledge, this is the first such report.