Describe the process of atherosclerosis and discuss two possible complications for the affected individual.

Concepts to consider: LDLs enter the inner layer of arteries and are phagocytosed by macrophages, which then become foam cells. The foam cells lead to the development of fatty streaks in the arterial walls. Smooth muscle fibers and connective tissue fibers migrate to the inner lining of the wall, along with white blood cells that produce substances that cause chronic inflammation of the wall. The buildup of these various cells and substances form the atherosclerotic plaque, which reduces the diameter of the artery and may eventually block it completely. The plaque also causes the walls to lose their ability to stretch.
As a consequence, tissues downstream from the plaque receive less blood and consequently less oxygen and nutrients. This may cause angina pectoris (chest pains) or even a myocardial infarction (heart attack). If a portion of the plaque breaks open, platelets may adhere and produce a clot, or thrombus. In the heart this can lead to cardiac arrest. In the brain this can lead to a stroke.