No abstract

Over seven million Americans suffer from chronic venous insufficiency, secondary to valvular dysfunction, with few effective clinical therapies. Chronic Venous Insufficiency (CVI) is a painful and debilitating disease that affects the superficial and deep veins of the legs. After deep venous thrombosis, the vein valves leaflets become adherent, fold over, or are absorbed into the vein wall. Incompetent valves allow reflux and subsequent pooling of blood in the legs. The resultant CVI causes severe leg edema, skin breakdown, and possible gangrene. Current clinical therapies are only modestly effective and include vein stripping and ligation, valvuloplasty, vein valve transposition, and vein valve transplantation. Valvuloplasty is the most definitive of CVI treatment, though this surgical treatment is rarely performed due to its difficulty. The quest for a better solution continues.

Venous valvular incompetency is a debilitating disease affecting millions of patients. Unfortunately, the current physiologic and surgical treatments are prone to the extreme risk of post-operative thrombosis. A new design for venous valves has been proposed using biomimicry. The medical device has the shape of a natural valve with sufficient elasticity to maintain patency and competency in the leg veins. The venous valve was tested for patency, competency, cyclic fatigue, compressibility, and thrombogenicity. Patency is maintained with a low opening pressure of less than 3 mmHg. Competency is maintained with backpressures exceeding 300 mmHg. The valve is fatigue resistant to over ¼ million cycles. The valve can maintain its integrity when compressed in a stent and deployed without tilting or mal-alignment. Little thrombus forms on the valve with perfusion of whole blood under pulsatile flow conditions. The preclinical tests demonstrate efficacy as a new venous valve for treatment of chronic venous insufficiency.