Arteriosclerosis

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Not to be confused with Arteriolosclerosis or Atherosclerosis.
Arteriosclerosis
Classification and external resources
ICD-10 I70
MeSH D001161

Arteriosclerosis is the thickening, hardening and loss of elasticity of the walls of arteries, from the Greek αρτηρία, meaning artery, and σκληρωτικός, meaning hardened.[1] This process gradually restricts the blood flow to one's organs and tissues and can lead to severe health risks brought on by atherosclerosis, which is a specific form of arteriosclerosis caused by the buildup of fatty plaques, cholesterol and some other substances in and on the artery walls.[2] As plaque continues to build, the blood and oxygen supply to the affected regions would drastically decrease due to the narrowing of the lumen. Eventually, the plaque build up could potentially lead to the complete occlusion of the arteries, leading to a variety of medical problems, like heart attack and stroke. These effects, and the lack of modern day medicine, caused arteriosclerosis to become the greatest killer of the 20th century.[3]

History[edit]

This phenomenon may have existed since ancient times; however, its diagnostics and clinical implications weren't recognized until the 20th Century. While many cases have been observed and recorded, the term arteriosclerosis wasn't used until Jean Fréderic Martin Lobstein coined it while he was analyzing the composition of calcified arterial lesions.[4] Arteriosclerosis later became the official scientific term after Gull and Sutton described arterio-capillary fibrosis and decided on using the former term instead.[5]

Modern Arteriosclerosis[edit]

In the US, and most other developed countries, arteriosclerosis, especially atherosclerosis, is the leading cause of illness and death. In 2008, the US had an estimate of 16 million atherosclerotic heart attacks and 5.8 million strokes. Cardiovascular diseases, caused by arteriosclerosis, caused almost 812,000 deaths in 2008, more than any other cause, including cancer With an estimate of 1.2 million Americans predicted to have a heart attack this year, the presence of arteriosclerosis is still holding on, despite advancements in medicine.[6]

Pathology[edit]

The lesions of arteriosclerosis begin as the intima in the arterial wall start to fill up with the deposition of cellular wastes. As these start to mature, they can take the form of arteriosclerosis obliterans, atherosclerosis, or Monckeberg’s arteriosclerosis. All three are linked through common features such as the stiffening of arterial vessels, thickening of arterial walls and degenerative nature of the disease.[7]

  • Arteriolosclerosis, unlike atherosclerosis, an arteriosclerosis is a sclerosis that only affects small arteries and arterioles, which carry important nutrients and blood to the body’s organs. The middle and inside portions of these arterioles become too thick and rigid, impeding blood flow through the region.
  • Atherosclerosis is the narrowing of arteries from a build up of plaque, made up of cholesterol, fatty substances, cellular waste products, calcium and fibrin, inside the arteries. This affects large and medium-sized arteries; however, its positioning varies person to person.[8]
  • Monckeberg's arteriosclerosis or medial calcific sclerosis is seen mostly in the elderly, commonly in arteries of the extremities. Characterized by calcification of the tunica media but without thickening of the intima or narrowing of the vessel lumen. A similar form of an intramural calcification, presenting the picture of an early phase of arteriosclerosis, appears to be induced by a number of drugs that have an antiproliferative mechanism of action.[9][10]

Etiology[edit]

There exists widespread disagreement as to the identity, processes, and history of arteriosclerosis. While some believe it to be related primarily to diet and to the lipid content of one’s blood, it’s unreliable because the statistical information is unable to explain the precise pathogenic nature of arteriosclerosis.[11] One possible origin of the arteriosclerotic lesion could be the endothelial dissemination. It is estimated that some tissue disorders may be initiation factors, combined with risk factors such as hypertension, promote more frequent occurrence of arteriosclerosis in some groups of individuals. However, the primary causes of arteriosclerosis are still unknown; however, it is more than likely that it is the organic end stage of a beginning functional derangement, and that factors such as diet, heredity, infections, etc., play important secondary roles in its development.[12]

Sub-Types[edit]

  • Hyperplastic: Hyperplastic arteriosclerosis refers to the type of arteriosclerosis that affects the lumen. The narrowed lumen is filled with thickened concentric smooth muscle cells, giving it the nickname “onion-skin.”
  • Hyaline type: Hyaline arteriosclerosis, also referred to as arterial hyalinosis and arteriolar hyalinosis, refers to lesions that are caused by the deposition of homogenous pink hyaline. This types of artery can be recognized by the specific glassy thickening of arterial and arteriolar walls.[13]

Risks and Complications[edit]

It’s been documented that those who suffer from arteriosclerosis commonly suffer from hypertension or high blood pressure. Arteriosclerosis can gradually progress, via repetitive injury to the inner arterial walls, into atherosclerosis and its complications. Although most symptoms of atherosclerosis don’t appear until a blockage occurs, they can range from arterial diseases, angina, arrhythmias, heart attack, stroke, etc… [5]

Treatment[edit]

Treatment is often in the form of preventative measures of prophylaxis.

Drug therapy for underlying conditions, such as statins/antihyperlipidemic drugs for the treatment of high cholesterol, drugs to treat high blood pressure (ACE inhibitors, Calcium channel blockers, etc.), and anti-coagulant drugs, are often prescribed to help prevent arteriosclerosis. These drugs can be prescribed singularly or in combination.

Lifestyle changes such as increasing exercise, stopping smoking, and moderating alcohol intake are also advised.

If the blood vessels that are narrowing are important (carotid artery, coronary artery), then sometimes more aggressive alternatives are necessary.

There are various types of surgery:

  • Angioplasty and stent placement: A catheter is first inserted into the blocked/narrowed part of your artery, followed by a second on with a deflated balloon which is passed through the catheter into the narrowed area. The balloon is then inflated, pushing the deposits back against the arterial walls, and then a mesh tube is usually left behind to prevent the artery from retightening.[2]
  • Coronary artery bypass surgery: This surgery creates a new pathway for blood to flow to the heart. Taking a healthy piece of vein, the surgeon attaches it to the coronary artery, just above and below the blockage to allow bypass.[14]
  • Endarterectomy: This is the general procedure for the surgical removal of plaque from the artery that has become narrowed, or blocked.[15]
  • Thrombolytic therapy: is a treatment used to break up masses of plaque inside the arteries via intravenous clot-dissolving medicine.

References[edit]

  1. ^ "arteriosclerosis" at Dorland's Medical Dictionary
  2. ^ a b Mayo Clinic Staff. "Arteriosclerosis / atherosclerosis". Mayo Clinic. Retrieved 12 February 2015. 
  3. ^ Dock, William. "Research in Arteriolosclerosis — The First Fifty Years". ACP. Annals of Internal Medicine. Retrieved 12 February 2015. 
  4. ^ Mayerl, Christina. "Atherosclerosis research from past to present". National Center for Biotechnology Information. Retrieved 12 March 2015. 
  5. ^ a b Mandal, Ananya. "What is Arteriosclerosis?". News-Medical. Retrieved 12 February 2015. 
  6. ^ "Atherosclerosis". Merck Manuals. Retrieved 13 February 2015. 
  7. ^ Mandal, Ananya. [Cit:http://www.news-medical.net/health/Arteriosclerosis-Types.aspx "Arteriosclerosis Types"]. News Medical. 
  8. ^ "Atherosclerosis". American Heart Association. Retrieved 14 February 2015. 
  9. ^ Arterial Vascular Effects of Non-steroidal Antiphlogistic Drugs - A Biochemical Model on an Intramural Induction of Arteriosclerosis, Rainer K Liedtke, MD
  10. ^ J. G. Mönckeberg: Über die reine Mediaverkalkung der Extremitätenarterien und ihr Verhalten zur Arteriosklerose. Virchows Archiv Jg. 1903, S. 141–167
  11. ^ Burch, G.E (March 1972). "The Etiology of Arteriosclerosis - A Thought". American Heart Journal: 1. 
  12. ^ Evans, Richard D. "The Etiology of Arteriosclerosis". Western journal of Medicine. 
  13. ^ "Hyaline Arteriolosclerosis". BrownMed. 
  14. ^ "Coronary artery bypass surgery". MedlinePlus. 
  15. ^ "Atherosclerosis -Treatment". UK NHS. Retrieved 21 November 2013.