Emerging mechanisms of vein graft failure: The dynamic interaction of hemodynamics and the vascular response to injury

Recently published data demonstrate that approximately 8 million men and women over 40 years of age have peripheral arterial disease and approximately, 20% of Americans greater than 65 years of age endure the symptoms of this disease process [1]. Despite its prevalence and cardiovascular risk implications, durable treatment options are limited, with only about 25% of PAD patients currently undergoing treatment. [2] Surgical revascularization using autologous vein remains among the dominant therapeutic options, with 110,000 peripheral bypass procedures performed in 2004. [1] Fueled by an epidemic of obesity and diabetes in the United States, substantial increases in the need for these interventions are projected over the next decade. Despite the escalating need for these often limb-and life-saving procedures, their medium and long-term durability remains compromised. Plagued by the problems of aggressive stenosis and luminal narrowing, contemporary data shows that almost 40% of lower extremity vein bypass grafts develop occlusive lesions or fail within a year (Fig. 1) [3]. Since many of the technical advancements for improved patency have been exhausted, the current concept is that the future of enhancing the durability of these reconstructions lies in a better understanding of the biology of the vein graft wall in response to interventions [4].