The Importance of Routine Graft Duplex in the Presence of Normal Ankle Brachial Indexes

Recent changes to our Medicare broker state that either a graft duplex or segmental pressures must be performed for routine follow-up for arterial bypass grafts. We have had several cases in which the ankle brachial index (ABI) has been within normal limits, 0.9, and the graft duplex has revealed an abnormality with the graft. The Intersocietal Accreditation Commission standard says that if a graft duplex is performed, the ABI must be included; the ABI must be done within 2 weeks at the same facility with no change in the patient's symptoms. When we obtained the patient histories, each patient noted no specific vascular claudicating symptom, but more general symptoms of weakness or pain in a specific area of the leg. It is important for laboratories to perform both tests. The ABI is a good indicator of disease in the normal population, but in older patients and those with diabetes, it can yield false-positive results.