atherosclerotic plaque formation: excess LDL cholesterol is oxidized by free radicles then taken up (phagocytosed) by macrophages (tissue monocytes) transform into faom cells that start secreting substances promoting endothelial cell prolifration (endothelium = cells lining the inside of vesseles).. foam cells accumulate over injured endothelium and form fatty streaks ..which progress into the atherosclerotic plaque..... anatomy...there is the left main coronary artery the right coronary artery..all arising from the ascending aorta..just above the aortic valve...cardiac (heart) perfusion occures during diastole ( heart relaxarion) (not as the rest of the body..during systole ( heart contraction).. if u want further info on the coronary anatomy..just ask..