Prediction of early graft failure with intraoperative completion duplex ultrasound scan

Abstract

Purpose: The purpose of this study was to determine intraoperative hemodynamic parameters that predict early failure of infragenicular vein grafts with intraoperative completion duplex ultrasound scan. Methods: We reviewed the results of intraoperative duplex scans that were selectively performed after completion of 45 tibial/pedal vein bypass grafts at high risk for failure. Bypass was performed for rest pain (39%) or tissue loss (61%), and 60% of the cases were disadvantaged because of compromised vein quality or poor arterial outflow. A 10-MHz low-profile transducer was used to scan the entire graft at bypass completion. All grafts were determined to be technically adequate (absence of retained valves, arteriovenous fistulas, or localized velocity increases and the presence of bypass-dependent distal pulses). Peak systolic velocity (PSV) and end diastolic velocity (EDV) were also measured at each anastomosis, in the outflow artery and in the proximal and distal portions of each graft. Resistive indices (RI) were calculated at each measurement point (PSV-EDV/PSV). Statistical analysis was performed with unpaired t test, X2 test, and multivariate analyses. Results: Twenty infragenicular vein bypass grafts (44%) thrombosed within 12 months. Intraoperative hemodynamic parameters were significantly different between grafts that remained patent or thrombosed. EDV was lower (5 ± 1 cm/s versus 13 ± 3 cm/s; P = .02) and RI was higher (0.90 versus 0.81; P