Supplementary Material

3 Movies

Files in this Data Supplement:

• Movie 1 - Movie 1 shows the flow dynamics in the epicardial capillary network with a capillary sinus. The capillaries were densely connected in patterns identified as H-, Y-, T- or hairpin type anastomoses, through which cross-connecting flows occurred abundantly. The flow directions of neighboring capillaries exhibited co- and counter-currents. The bulbous vessel in the right middle of the panel is a capillary sinus. The capillary sinus exhibited significant diameter change from end-diastole to end-systole. The inflow from proximal capillary was drained into the capillary sinus during diastole and the stored blood was squeezed out to the peripheral capillary mostly in the next systole. In individual capillaries flow was predominant either during systole or during diastole. For example, the flow of the capillary overriding the capillary sinus was obviously systolicpredominant.
• Movie 2: Control - Movie 2 shows the epicardial capillary network before and during left anterior descending artery (LAD) occlusion (control).
• Movie 3: Reactive Hyperemia (RH) - Movie 3 shows the capillary network during LAD occlusion and after the release of the LAD (RH). The superimposed tracings in the movie indicate great cardiac vein (GCV) flow, LAD flow, electrocardiogram, and aortic pressure, in descending order. During occlusion of the LAD, visible collapse of capillaries was not observed. During RH, the flow enhancement of capillaries accompanied by increment in both velocity and diameter was clearly noticed, but visible capillary recruitment was not detected.