Narrowed artery due to cholesterol
Illustration of the narrowing of an artery (athe- rosclerosis) due to high blood levels of the low- density lipoprotein (LDL) particle, a form of blood cholesterol. The artery is seen cut through, with red blood cells and yellow LDL particles escaping. The lumen of the artery has narrowed due to an accumulation of LDL particles beneath the inner elastic wall (white) and the smooth muscle (red). Calcium crystals may also form here. LDL particles are complex lipid structures containing cholesterol in their core. Cardio-vascular research has shown that these LDL particles, when occurring in high levels in the blood, increase the risk of coronary heart disease and stroke.