Prevention of vein graft intimal hyperplasia with photochemical tissue passivation

Long-term patency rates are poor after coronary or lower extremity bypass with autologous vein. This is largely due to intimal hyperplasia (IH), superimposed accelerated atherosclerosis, and graft thrombosis. A key inciting event is graft overdistention and endothelial denudation after exposure to arterial pressure. Limiting overdistention by external mechanical support has been shown to reduce IH. Photochemical tissue passivation involves cross-linking adventitial collagen, a novel approach to limit overdistention of the vein without an external prosthesis. Photochemical tissue passivation resulted in a 57% reduction of IH. Minimizing vein graft IH would greatly improve long-term outcomes after arterial bypass.