Microvascular vein graft. A, Vessel ends excised, leaving gap. Arrows show direction of flow in vessel. B, Vein graft harvested and reversed to allow flow through valves. Microvascular clips help stabilize and control vessels and graft. C, Microvascular clips in place; anastomoses have been completed. Valves in vein graft allow for proper direction of blood flow. SEE TECHNIQUE 63.3.