Health Priorities Report
Cardiovascular disease (CVD) has been identified as a health priority area because it is major health and economic burden on Australia. It is one of the leading causes of sickness and death in Australia, although there are significant differences in the incidence and prevalence of the disease among population subgroups. CVD can be attributed to a number of modifiable risk factors.
The nature of CVD
Cardiovascular disease (CVD) refers to damage to, or disease of, the heart, arteries, veins and/or smaller blood vessels. The three major forms of this disease are: * Coronary heart disease – the poor supply of blood to the muscular walls of the heart by its own blood supply vessels, the coronary arteries * Stroke – the interruption of the supply of blood to the brain * Peripheral Vascular disease – diseases of the arteries, arterioles and capillaries that affect the limbs, usually reducing blood supply to the legs
Cardiovascular disease is most evident as stroke, heart attack, angina, heart failure and peripheral vascular disease. Atherosclerosis is the underlying cause of most of these conditions. This is the build-up of fatty and/or fibrous material on the interior walls of arteries. This build-up hinders the flow of blood to the body’s tissues and also acts to increase blood pressure. Often, the build-up occurs in patches known as atheroma (thickened area of fatty and fibrous deposits on the inside surface of arteries, resulting in atherosclerosis) or plaque, and is characterized by presence of cholesterol. The development of atheroma tends to decrease the elasticity of the arteries and limits the flow of blood.
Coronary Heart Disease
Coronary heart disease, also known as ischemic heart disease, is the most common form of heart disease. The two major clinical forms are heart attack and angina. Angina is chest pain or discomfort caused by insufficient blood flow and oxygen to the muscle of the heart. Coronary artery disease is caused by a buildup of fatty deposits on the inside of the arteries. These deposits are made up of cholesterol, calcium and other substances in the blood. This buildup is called atherosclerotic plaque or simply plaque. Plaque deposits can clog the coronary arteries and make them stiff and irregular. There may be a single blockage or multiple, and they can vary in severity and location. These deposits slowly narrow the coronary arteries, causing your heart to receive less blood and oxygen. This decrease in blood flow may cause angina, shortness of breath or extreme fatigue. A complete blockage can cause a heart attack.
Figure on the right is a diagram of a normal blood flow (on the right) and an abnormal blood flow (on the left) caused by atherosclerosis.
Cerebrovascular disease (stroke)
A stroke occurs when an artery supplying blood to a part of your brain is blocked or bursts. The blood supply is interrupted or severely reduced, depriving that part of the brain of the oxygen and nutrients it needs to function. Without oxygen and nutrients, the cells in the affected area of the brain die and function in this area of the brain is lost. Dead brain cells are generally not replaceable, that’s why the effects of stoke can be permanent. In some cases, some brain cells survive and recover, depending on how much the blood supply to those areas was reduced during the stroke. There are two types of stroke:
* Ischaemic – where a blood clot forms and blocks an artery supplying blood to the brain * Haemorrhagic – where an artery supplying blood to the brain ruptures, causing blood to spill into the surrounding tissue so that not enough blood reaches the brain.
Common symptoms of stroke are the sudden onset of one or more of the following:
* Loss of strength of the face, arm and/or leg on either or both sides of the...