Access Flow after Angioplasty Predicts Subsequent Arteriovenous Graft Survival

Abstract

The effectiveness of angioplasty can be assessed by access blood flow (ABF) measurements after the procedure; however, ABF after angioplasty is highly variable. The purpose of this study was to determine if the level of ABF achieved after angioplasty of arteriovenous (AV) grafts was predictive of subsequent graft outcomes. Retrospective review was performed of 51 shunt images in 31 patients who were receiving dialysis via functioning AV grafts. Patients were referred for shunt imaging because of low ABF rates, increased venous pressure, or clinical indications. Only those patients with ABF measurements performed less than 1 month after angioplasty were included. Patients were then followed for at least 12 months after the initial angioplasty and access-related events were recorded (eg, thrombosis, repeat angioplasty, infection, loss of access). Average ABF rates increased from 655 mL/min+/-45 before angioplasty to 946 mL/min+/-50 after angioplasty. The median ABF rate after the procedure was 1,040 mL/min. Grafts with an ABF rate after angioplasty of less than 1,000 mL/min were more likely to require repeat intervention and to exhibit thrombosis within the first 6 months compared with those with ABF rates greater than 1,000 mL/min. They also had a lower 1-year assisted patency rate (ie, graft survival). The most important determinant of flow after angioplasty was the ABF before angioplasty. Grafts with an ABF rate greater than 1,000 mL/min after prophylactic angioplasty required fewer repeat interventions and had longer assisted patency after prophylactic angioplasty than those with ABF rates less than 1,000 mL/min.