Effect of different POS:DOS ratios on hemodynamics at the distal end-to-side anastomosis of a bypass graft

Intimal hyperplasia (IH), especially at the distal end-to-side anastomosis, is a major cause of long term failure of arterial bypass grafts. Hemodynamic factors are believed to be directly related to the development of intimal hyperplasia. The flow ratio between the proximal outlet segment (POS) and the distal outlet segment (DOS) may be one of the factors which influence the hemodynamic environment in the anastomosis. This is of interest since two recent studies have shown that the site of greatest IH formation varies from the artery floor to the graft hood under occluded vs. partial POS outflow, respectively. In this study, a pulsatile flow in vitro model of the distal end-to-side anastomosis of an arterial bypass graft was used to examine the effects that different POS:DOS flow ratios have on the flow patterns and the distributions of hemodynamic factors in the anastomosis