HUMAN CARDIAC AND RESPIRATORY SYSTEMS

Sunday, 9 May 2010

5.1 Describe the changes in artery structure associated with circulatory disease.

Heart disease is mainly caused by choice of lifestyle. The main offenders of this is smoking and diet.
When arteries become clogged this means that the heart will be receiving an insufficient supply of Oxygen which can lead to a condition known as Angina or even a heart attack.
Many different Arteries around the body could be subject to blockages and can affect many different organs and body parts.

picture from; http://www.nlm.nih.gov/medlineplus/ency/imagepages/18018.htm


Coronary Artery Disease (CAD) occurs when fatty deposits known as plaque build up in the artery walls allowing little or no blood to pass through. This forms a blood clot.
Too much cholesterol build up in the blood stream is one of the major causes of CAD. The plaque forms in the arteries over many years in a process called atherosclerosis. The plaque hardens in the passageways of the arteries which supply Oxygen rich blood to the major organs. Also pieces of the plaque fall of the wall of the arteries and travel in the blood stream where it can eventually block the flow of blood.










picture from:
http://www.nhlbi.nih.gov/health/dci/Diseases/Atherosclerosis/Atherosclerosis_WhatIs.html

The Arterial walls consists of the endothelium which is the inner wall that allows the blood to flow through smoothly, the media which is the muscle and elastic tissue that allows for the artery to cope with the high pressure of blood flowing through, and the adventita, this is the tough outer shell that protects the artery.
Carotid artery disease is when the arteries in both sides of the neck become blocked due to the fatty deposits clogging up on the endothelium. This causes the brain to have an insufficient supply of oxygen rich blood and can lead to stroke.
Pheripheral artery disease occurs when major arteries in the legs, arms and pelvis become blocked due to the fatt deposits. This can lead to serious infections (gangrene) or unbearable pain.
High blood pressure can damage the vessel walls because of the blood being constantly forced through them.
Some of the circulatory diseases may occur because they are heriditary i.e. high blood pressure,
These conditions can be avoided.

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