Flow in hemodialysis grafts after angioplasty: Do radiologic criteria predict success?

Background. The anatomic success of percutaneous angioplasty of venous stenosis is determined by the improvement in cross-sectional diameter of the vessel. A successful outcome is defined as a residual stenosis of < 30%. The purpose of this study was to determine whether the angiographic assessment of a venous stenosis correlates with the change in graft blood flew following angioplasty. Methods. Twenty-two hemodialysis patients with decreased intragraft blood flow (< 700 mL/min) underwent diagnostic fistulography and angioplasty. All grafts were patent at the time of the procedure. Intragraft blood How was measured before and after angioplasty using the ultrasonic dilution technique. Change in graft blood flow after angioplasty was correlated to the morphologic changes of the treated stenosis. Results. The mean preangioplasty and postangioplasty graft blood Hows were 457 +/- 136 and 818 +/- 202 ml:min, respectively. The mean degree of stenosis before angioplasty was 74 +/- 15% and 18 +/- 14% after dilation (P < 0.001). The only variable that significantly correlated with postangioplasty blood flow was preangioplasty flow (r(2) = 0.22 P < 0.001), The postangioplasty blood How was not significantly different than the highest recorded blood How measured in that graft (798 <plus/minus> 213 mL/min, P = NS). There was no significant correlation between the change in blood How and the change in percentage of stenosis, Conclusion. Following angioplasty of a venous stenosis, the graft blood How is most closely predicted by the preprocedural blood flow and is similar to the highest recorded blood flow ever measured in that graft. Angiographic criteria to assess the success of angioplasty are not predictive of changes in blood flow.