A perioperative technique for detection of retained valve cusps in the in situ vein graft

A problem of the in situ vein bypass technique is the retained value cusp. To ensure that maximum flow has been obtained through the vein graft after valvotomy, a simple perioperative technique has been developed. This consists of infusing normal saline solution into the vein and comparing the distal to proximal (antegrade) flow with the proximal to distal (retrograde) flow under the same conditions. Twelve consecutive in situ vein grafts have been assessed. Antegrade and retrograde flow measurements were similar in four of the grafts but different in eight (40% to 80% reduced retrograde flow). Valvotomy was repeated and subsequent measurements of retrograde flow were similar or greater than the antegrade. The technique described is simple, reproducible, inexpensive, and may prove useful for routine intraoperative evaluation of valvotomy of in situ vein grafts.