Coronary perfusion pressure and inflow resistance have different influence on intramyocardial flows during coronary sinus interventions.

A mathematical model is used to represent the vascular bed of the left coronary circulation by an arterial, a capillary and a venous compartment. The model is first adjusted so as to reproduce arterial hemodynamics known from measurements during normal perfusion. Additionally, measurements under coronary sinus occlusion are used to assess the venous section of the model. While the calculated phasic shapes of epicardial flows are seen to agree with measurements, intramyocardial flows, which are inaccessable to measurement, are predicted from the model. The model is run under stepwise changes of coronary perfusion pressure and coronary artery resistance for both the normal state and coronary sinus occlusion. Intramyocardial flow between capillaries and veins, being the main determinant for a possible therapeutic effect of coronary sinus interventions, is estimated.