Smooth muscle cells of human veins show an increased response to injury at valve sites

Valves are a common site of venous thrombosis and of vein graft lesions. However, there is essentially nothing known about the response to injury of either animal or human valve sinus cells. The novel observation that the smooth muscle cells of the human valve sinus exhibit an exaggerated response to injury compared with smooth muscle cells of the nonvalve wall may help explain the propensity of the valves to fail after thrombotic events and for the valve wall to fail in arterial bypass grafts.