Neointimal hyperplasia causes vascular graft failure as a result of hypertrophy of -
Neointimal hyperplasia (or also known as intimal hyperplasia) is a response to vascular injury and is seen as a complication of all forms of arterial reconstruction.
Intimal hyperplasia followed by stenosis or restenosis is the principle cause of failure in vascular grafts.
Intimal hyperplasia occurs because of smooth muscle cells. These SMCs


are activated by vascular injury
migrate from media to the intima
multiply as intimal SMCs
synthesize & deposit extracellular matrix.
Enodthelial cells
Collagen fibers
Smooth muscle cells
Elastic fibers