Blood Velocity Patterns in Poststenotic Regions and Velocity Waveforms for Myocardial Inflow Associated With Coronary Artery Stenosis in Dogs

Velocity profiles across a vessel were investigated in poststenotic regions of the canine left coronary artery by our 80-channel 20 MHz ultrasound velocimeter. The velocity waveform in a small artery just before its penetration into myocardium was measured by our laser Doppler method. The poststenotic velocity configuration was characterized by a narrow region of high velocity with diastolic reverse flow near the wall which may dissipate energy. The velocity waveform in the distal small arteries exhibited increased systolic reverse flow with decreased diastolic forward flow, resulting in a remarkable reduction of coronary inflow into the myocardium.