Atherosclerosis is popularly referred to as "hardening of the arteries." It's the result of cholesterol and other fatty material being deposited along the inner walls of the arteries. The condition has different manifestations, depending on which arteries are affected; it causes coronary artery disease (CAD) in the heart, cerebrovascular atherosclerosis in the brain and peripheral artery disease (PAD) in the limbs. The walls of the arteries, in response to the deposition of fatty material, also thicken. The result is a progressive reduction in the flow of blood through the affected vessels. These effects are especially damaging in the heart; CAD is the leading cause of death in the United States and other industrialized countries. Many factors contribute to the development of atherosclerosis, including a diet high in fat and cholesterol, smoking, hypertension, increasing age and a family history of the condition. Women of reproductive age are generally at lower risk of atherosclerosis due to the protective effects of estrogen. Medications typically used to treat atherosclerosis include nitroglycerin (which is also used in the treatment of angina, or chest pain) and calcium channel blockers and beta blockers (which are also used in the treatment of high blood pressure, or hypertension; see "Antihypertensives" for more on these drugs). Sometimes, individuals with CAD may need what's known as a revascularization procedure, to re-establish the blood supply — typically a coronary artery bypass graft or angioplasty. If such a procedure is successful, the individual may be able to return to diving after a period of healing and a thorough cardiovascular evaluation (see "Issues Involving Coronary Artery Bypass Grafts.").