If your risk is high, you might also take medicines that lower your risk. These include medicines to lower cholesterol and blood pressure.
Although the exact process is not completely understood, scientists have described three different stages of atherosclerosis that lead to clogged arteries. These stages do not necessarily occur in order, nor is there always a progression from one stage to the next. The fatty streak. The "fatty streak" appears as a yellow streak running inside the walls of the major arteries, such as the aorta. The streak consists of cholesterol, white blood cells, and other cellular matter.
The fatty streak by itself does not cause symptoms of heart disease but can develop into a more advanced form of atherosclerosis, called fibrous plaque.
The plaque. A plaque forms in the inner layer of the artery. Plaque is a buildup of cholesterol, white blood cells, calcium, and other substances in the walls of arteries.
Over time, plaque narrows the artery, and the artery hardens. Plaque sometimes reduces blood flow to the heart muscle, which can cause angina symptoms. Plaque in the large artery in the neck carotid artery stenosis may block blood flow to the brain and is a common cause of transient ischemic attack sometimes called "mini-stroke" and stroke. Stable and unstable plaque. Plaques are defined based on the risk that they will tear or rupture. Stable plaque is less likely to rupture.
These plaques have a thick fibrous cap and are made up of substances that are stable and not likely to rupture. Unstable plaque is more likely to rupture. These plaques have a thin fibrous cap and are made up of substances like fats that can expand.
Inflammation within the plaque can make the fibrous cap unstable and more likely to tear apart. Blocked artery. A blockage in the artery can happen if the plaque tears or ruptures. This rupture exposes the cholesterol and tissue that was under the fibrous cap. Blood clots form in response to this rupture. The blood clot blocks the blood flow in the artery. This can cause a heart attack or stroke. This theory suggests that atherosclerosis develops as a result of repetitive injury to the inner lining of the artery.
Injury may stimulate cells to grow and divide as part of the inflammatory process. This normal, healing response to chronic injury may actually result in the growth of atherosclerotic plaque. Smoking plays a large role in the development of atherosclerosis.
The carbon monoxide and nicotine contained in tobacco smoke affect blood flow through your arteries by:. Atherosclerosis is one of the major causes of abdominal aortic aneurysm. Besides aging, factors that may increase your risk of atherosclerosis include:. Atherosclerosis can also cause aneurysms, a serious complication that can occur anywhere in your body.
An aneurysm is a bulge in the wall of your artery. Most people with aneurysms have no symptoms. Pain and throbbing in the area of an aneurysm may occur and is a medical emergency. If an aneurysm bursts, you may face life-threatening internal bleeding. Although this is usually a sudden, catastrophic event, a slow leak is possible. If a blood clot within an aneurysm dislodges, it may block an artery at some distant point. The same healthy lifestyle changes recommended to treat atherosclerosis also help prevent it.
These include:. Just remember to make changes one step at a time, and keep in mind what lifestyle changes are manageable for you in the long run. Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission.
This content does not have an English version. This content does not have an Arabic version. Overview Arteriosclerosis and atherosclerosis are sometimes used to mean the same thing, but there's a difference between the two terms. Request an Appointment at Mayo Clinic. Development of atherosclerosis Open pop-up dialog box Close. Development of atherosclerosis If you have too many cholesterol particles in your blood, cholesterol may accumulate on your artery walls.
Share on: Facebook Twitter. Show references Atherosclerosis. National Heart, Lung, and Blood Institute. Accessed Feb. American Heart Association. Zhao X. Pathogenesis of atherosclerosis. Jung J, et al. This disease process can be seen in any blood vessel in the body and is the cause of coronary artery disease , stroke , and peripheral arterial disease PAD.
When atherosclerosis develops in any blood vessel of the body, be it a large artery like the aorta or a small one like a coronary artery, a plaque forms inside the blood vessel. This plaque appears like a yellow, firm, shiny layer in the inside of a blood vessel. The wall of the aorta and all blood vessels is a dynamic tissue made up of living cells, requiring nutrients and oxygen. Many of these nutrients seep from the inside of the blood vessel through the walls to nourish the rest of the blood vessel.
When the inner lining of the vessel is covered with an atherosclerotic plaque, nutrients can no longer seep through sufficiently. The cells receive no oxygen, and some of them die.
As the atherosclerosis progresses and cells continue to die, the walls become weaker and weaker.
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