Heart Pulmonary Coronary arteries, Vena arery cava accompanied by two or more veins. Circumflex A 160-um vein giving rise to small venules and branching rapidly into parallel LAD capillaries. Coronary veins(blue) Non directional Temporal distribution of capillaries:perfused during diastolic;collapsed during systolicCoronary arteries, accompanied by two or more veins. A 160-um vein giving rise to small venules and branching rapidly into parallel capillaries. Non directional Temporal distribution of capillaries: perfused during diastolic; collapsed during systolic Heart