Initial experience with color-flow duplex scanning of infrainguinal bypass grafts.

Seventy-eight infrainguinal grafts were evaluated by means of color-flow duplex imaging to demonstrate its utility in the routine surveillance of leg grafts as well as in the evaluation of grafts in which a problem is already suspected. Stenoses were identified in 15 (20%) of 76 grafts evaluated for screening purposes. Seven of these had confirmatory arteriograms, and five were revised. The remaining eight grafts with suspected stenoses were followed without angiography, and four (50%) subsequently failed. Only two (3.3%) of 61 grafts with normal scan outcomes have thrombosed. Fistulas were identified in 12 (37%) of 32 in situ grafts evaluated. Nine grafts with previously suspected problems based on decreased ankle-brachial indexes were scanned, and an explanation was found, confirmed by angiogram, and corrected in six. Detection of unsuspected stenoses in five grafts requiring revision and four grafts that later thrombosed without revision, as well as identification of fistulas in 37% of in situ grafts, confirms the importance of color-flow imaging as a screening tool.