Hemodynamics of coronary artery - Saphenous vein bypass using Laser Doppler anemometry.

An experimental investigation of the detailed laminar velocity distribution of a suspension of red blood cell ghosts at normal hematocrits in an idealized model of the coronary artery-saphenous vein bypass is obtained using Laser Doppler Anemometry. The flow is maintained by a pulsatile applied pressure gradient which approximates the pressure history variation in the ascending aorta. The velocities are determined by measuring the Doppler shifted frequency of laser light scattered by the moving red blood cell ghosts. Using four different model bypasses it was determined that turbulent flow at the graft-coronary intersection can be delayed by decreasing the discontinuity in diameter between the bypass vein and coronary artery and by decreasing the bypass vein and host coronary artery intersection angle. (A)