Prosthetic Vein Valve Designed to Improve Blood Flow

David Ku has led research at the Georgia Institute of Technology on a prosthetic vein valve to treat chronic venous insufficiency.

Engineers at the Georgia Institute of Technology (Georgia Tech, Atlanta, GA, USA) have developed a prosthetic vein valve to treat chronic venous insufficiency, which occurs when valves in the veins can no longer ensure a one-way flow of blood back to the heart.

“Blood flows to the toes because of gravity, but the body uses vein valves to pump blood in one direction back to the heart,” explains David Ku, professor of mechanical engineering at Georgia Tech University. Ku says that the vein valves can dissolve in response to blood clotting, which results in blood flowing the wrong way, ultimately causing swelling in the legs.

Ku is leading a research team that has developed a prosthetic vein valve to replace damaged, non-functioning valves. The prosthetic vein valve design and results from laboratory studies were presented at the Society for Biomaterials Fall Symposium.

Individuals with chronic venous insufficiency are commonly prescribed therapies including anticoagulants, bed rest, and compression hosiery, all of which target disease symptoms rather than its cause. Damaged vein valves sometimes can be repaired, but when that isn’t possible, some surgical options are available to replace deep venous valves such as valve transplantation. Replacing the valve with a prosthetic one is likely the better option, however, because finding a suitable donor valve in one of the patient’s legs can be difficult, according to Ku. “Previous studies have shown that even if a donor valve is found, implanting it can cause significant trauma to the patient’s leg,” Ku adds, who has doctoral degrees in mechanical engineering and medicine. “To avoid these complications, other prosthetic vein valves have been designed, but most have demonstrated poor clinical potential for humans.”

Ku and his collaborators believe the valve they have developed will overcome previous difficulties. The one-way flap is made of polyvinyl alcohol cryogel, a material patented by Georgia Tech in 1999. The material is biocompatible, has adjustable mechanical strength, and has flexibility comparable to that of body tissue.

The researchers will begin conducting preclinical animal trials in October to test the in vivo biocompatibility and performance of the prosthetic vein valve prototype in sheep. Sheep were chosen because their cardiovascular geometry and physiology are similar to those of humans.

Tags: chronic venous insufficiency, David Ku, Georgia Institute of Technology, Georgia Tech, prosthetic valves