Both the animal experiments and the theoretical calculations were used to assess the effect of a partial obstruction of a coronary artery. These studies were undertaken in the hope of finding hemodynamic parameters measurable at operation which could indicate the severity of diffuse distal coronary artery disease. Measured parameters included mean coronary artery flow, systolic flow, diastolic flow, peak-to-peak flow amplitude and maximum reactive hyperemic flow. The amplitude of the flow, the diastolic/ systolic flow ratio and the maximum reactive hyperemic flow were all found to be more sensitive indicators of the degree of vessel obstruction than the mean flow. Theoretical calculations based on Poiseuille's Law give close agreement with the experimental findings. It is hoped that measurement of these sensitive parameters at operation will be of prognostic value in determining the patency rate of aorto-coronary bypass grafts.
ASJC Scopus subject areas