O104: The “At-Risk” Infrainguinal Bypass Graft: benefit of Duplex Ultrasound Surveillance and Institutional costs of failure

Abstract Introduction The “Achilles heel” of infrainguinal surgical revascularisation (IISR) is that of restenosis. Duplex Ultrasound Surveillance (DUS) is undertaken to identify restenosis to permit intervention to maintain graft patency. We report the impact of DUS on outcomes focusing on patient- and treatment-associated costs. Methods Consecutive patients undergoing IISR at our Institution were assessed (January 2017 - December 2020). Data on DUS (1-, 6- and 12-month scans) were collated. Primary outcomes were mortality and major limb amputations (MLA) at 2-years post IISR. Grafts were defined “at-risk” if radiological evidence of significant graft stenosis or occlusion, with or without symptoms, was identified. Post IISR graft-specific Institutional costs for all patients were quantified. Results 254 patients had IISR in the observed period (196 men, median age 70yrs). Of those, 194 (76%) entered DUS, and 109 (43%) completed it. In patients who completed DUS (vs incomplete vs none), mortality was 6.4%, (vs 26.5% vs 38% respectively; p <0.001) and MLA rates were 6.4% (vs 12% vs 30%, p=0.174 and p<0.001 respectively). Managing at-risk grafts led to additional 384 cross-sectional imaging requests, 284 outpatient reviews, 933 hospital admission days and 233 open and endovascular reinterventions with a total additional NHS cost of £ 1.348.518 in 2 years. Per-patient costs were £216 (per patient, per month) for the complete DUS group vs £348 in no DUS group. Conclusion The ongoing management of IISR is associated with significant costs. Enrolment in and completion of a DUS programme is associated with improved patient outcomes and a reduction in costs.