Early detection of saphenous vein arterial bypass graft stenosis by color-assisted duplex sonography: a prospective study.

We propose a simple and rapid technique for the postoperative surveillance of developing stenosis in lower extremity saphenous vein arterial bypass grafts that uses color-assisted duplex sonography. Color Doppler flow images are used to identify points of altered flow dynamics. These points are subsequently analyzed by duplex sonogra- phy, with doubling of the peak systolic velocity at the point of suspected stenosis considered the diagnostic threshold for significant stenosis. A segment-by-segment comparison made with arteriography in 14 patients (15 grafts, 92 segments) showed this approach to be 95% sensitive (18/19) and 100% specific (73/73) for the detection and localization of focal graft stenoses that involve greater than 50% narrowing of the lumen diameter. We conclude that color-assisted duplex sonography can accurately detect the pres- ence of saphenous vein arterial bypass graft stenoses.