Understanding and treating vein graft atherosclerosis

Vein grafts have been used as bypass conduits for coronary artery disease since the 1960s. This widely used treatment, however, is complicated by the development of changes in the vein graft, which resemble atherosclerosis and are often termed as such. They occur at about 10 years, which leads to the need for reoperation in some patients. The purpose of this review is to summarize the knowledge regarding the pathophysiology of vein graft "atherosclerosis," as well as promising new treatments for this disease.

The relevant literature relating to the epidemiology, histology, cell and molecular pathophysiology and treatment of vein graft atherosclerosis is reviewed.

The development of vein graft atherosclerosis differs from arterial atherosclerosis. Studies have examined the role of trauma, lipids, vasoactive mediators, smooth muscle cell mitogens, smooth muscle cells apoptosis, adhesion molecules and proteases. Therapies have been developed to prevent vein graft atherosclerosis based on these studies and have been tested using animal models and in patients.

Promising new therapies have been developed based on current knowledge and further applications of genomics will allow for the further identification of risk factors and mechanistic insights. The use of arterial grafts such as the internal mammary artery, which have higher patency rates at 10 years compared with vein grafts as well as approaches to revascularize infarcted myocardium may one day replace the use of vascular conduits.