In arteriosclerosis, there is a thickening, hardening, and loss of elasticity of the walls of arteries. The name arteriosclerosis is often used interchangeably with the term "atherosclerosis;" however, atherosclerosis is technically a type of arteriosclerosis. The name atherosclerosis comes from the Greek words "athero" (gruel or paste) and "sclerosis" (hardness). The term arteriosclerosis comes from the words "arterial" (artery) and "sclerosis" (hardness).
Arteries are blood vessels that carry blood from the heart to the rest of the body. Healthy arteries are flexible, strong, and have a high degree of arterial elasticity, or flexibility. As people age, an increase in arterial stiffness is normal. Increased arterial stiffness may restrict blood flow to vital organs and is associated with an increased risk of heart attack and stroke.
Atherosclerosis results from the accumulation of plaque in artery walls. Plaque is made up of fat, cholesterol (particularly low density lipoprotein (LDL) cholesterol), calcium, and other substances found in the blood. Plaque accumulation causes a narrowing and a loss of elasticity of the arteries. Over time, plaques can grow in size and may partially or totally block the blood's flow through an artery. A build-up of plaque, or a clot that forms if a plaque ruptures, may block an artery, cutting off blood and oxygen supply to vital organs, which may cause a heart attack or stroke. A piece of the clot may also break off and enter the blood stream. Most commonly, the clot will travel to the legs or the lungs. This may result in an obstruction of blood flow, which in the leg, can result in a deep vein thrombosis (DVT), or in the lung, a pulmonary embolism (PE). Although plaques may occur anywhere in the body, they usually cause problems in the heart, brain, and legs.
Arteriosclerosis may begin early in life and not present any problems or symptoms or even be diagnosed until a plaque has grown so large that it ruptures. However, others experience symptoms such as chest pain, shortness of breath, or leg pain, especially with exercise.
A plaque deposit may block blood flow to a particular area of the body, which decreases the amount of oxygen reaching that area. The result is that the supply of oxygen does not meet the body's needs. When someone exercises, oxygen demand increases and the heart pumps faster, fulfilling this increased need in healthy patients. In patients with arteriosclerosis, plaque deposits inhibit blood flow, and even though the heart is pumping faster, not enough oxygen reaches the tissues, which is why these symptoms are typically more noticeable during physical activity. The tissues that are normally nourished by the blood carried in the artery do not received oxygen and begin to shut down, causing the tissue to die.
The endothelium is a thin layer of cells on the inner wall of arteries. Healthy endothelium keeps the inside of arteries toned and smooth, which keeps blood flowing properly. It is believed that endothelial dysfunction, caused by local damage, may trigger plaque formation. Endothelial dysfunction is caused by oxidative stress resulting from excessive levels of free radicals and low levels of antioxidants. Although the endothelium naturally hardens with age, there are some lifestyle factors that may speed up the process. For example, the endothelium may be damaged when a person eats a diet high in cholesterol and fat, has high blood pressure, and/or uses tobacco products. These factors may cause or worsen arteriosclerosis by causing new plaque deposits to form and others to grow larger.
Plaque formation is the result of an inflammatory process due to endothelial dysfunction. When LDL cholesterol particles invade the endothelium, they become oxidized, which triggers an immune response. Monocytes (white blood cells) attack the LDL particles and engulf them in an attempt to remove them. Instead, they slowly form larger cells, called foam cells, which propagate the immune response. Atherosclerotic lesions occur at the site of plaque deposits. Over time, they grow larger due to cell division, fat build-up, and the formation of connective tissue. The result is hardening and thickening of the arteries, accompanied by restricted blood flow and impaired circulation.
In most people, atherosclerosis may be prevented by adopting a healthy lifestyle and avoiding certain risk factors. Once atherosclerotic lesions have been detected, medications, lifestyle changes, or possibly surgery may be implemented to prevent disease progression and complications.

Related Terms

Aneurysm, angina, angioplasty, arterial elasticity, arterial stiffness, arteriosclerosis, atherosclerosis, atherosclerotic lesion, blood pressure, blood vessels, cardiovascular disease, cardiovascular health, cerebrovascular disease, cholesterol, coronary artery disease, EKG, electrocardiograph, endothelial dysfunction, hardening of the arteries, heart, heart attack, heart disease, heart disorders, heart failure, high blood pressure, high cholesterol, hyperlipidemia, hypertension, myocardial infarction, peripheral artery disease, plaque, stroke, transient ischemic attacks.

types of the disease

Coronary artery disease: When atherosclerotic plaques occur in the arteries of the heart, a person may experience angina. Angina is chest pain that may occur at rest or intensify during physical activity. If the plaque suddenly ruptures and causes blood clots to form, the heart tissue does not receive oxygen and begins to die. The result is a heart attack, or myocardial infarction. According to the National Institutes of Health (NIH), coronary artery disease is the leading cause of death for both men and women in the United States. Coronary artery disease is also used interchangeably with coronary heart disease.
Cerebrovascular disease: Atherosclerotic plaques may occur in the arteries of the brain. Eventually, the plaque may rupture, which leads to the formation of a blood clot. The clot may block the vessel, cutting off blood and oxygen supply in the brain. This may cause either a transient ischemic attack (temporary without causing permanent damage) or a stroke (which results in tissue death). Strokes may also occur when a plaque ruptures elsewhere in the body, resulting in the formation of a blood clot. A piece of the blood clot may break off (called an embolus) and travel to the brain, occluding (obstructing) an artery and leading to a lack of oxygen and tissue death. Strokes may cause permanent brain damage or even death.
Peripheral artery disease (PAD): Peripheral artery disease (PAD) is the progressive hardening and narrowing of the arteries due to atherosclerotic plaque formation in the arteries of the lower extremities. A common symptom of PAD is intermittent claudication, which is described as pain, fatigue, discomfort, or numbness in the lower extremities (particularly in the thigh or calf muscles) during exercise that resolves with rest. In more advanced PAD, this lower extremity pain may also occur at rest. The lack of blood flow to the extremities results in poor wound healing, which may sometimes lead to amputations.