Leading Causes of Death
1900 | 2000 |
1. Pneumonia and Influenza 2. Tuberculosis 3. Diarrhea 4. Heart disease 5. Stroke 6. Kidney disease 7. Accidents 8. Cancer 9. Senility/dementia 10. Diphtheria |
1. Heart disease 2. Cancer 3. Stroke 4. COPD 5. Accidents 6. Diabetes 7. Pneumonia and Influenza 8. Alzheimer disease (dementia) 9. Kidney disease 10. Septicemia |
Heart diseases include coronary artery disease (CAD), heart attack and congestive heart failure. The disease starts developing when your coronary arteries are narrowed or blocked by plaque build-up in the inside walls. This condition is called atherosclerosis. As a result, oxygen-rich blood cannot reach your heart muscle in sufficient amounts and on time.The aggravation of these conditions causes angina or a heart attack.
Atherosclerosis
Arteriosclerotic Vascular Disease or Atherosclerosis is a potentially serious condition when an artery wall thickens and get clogged up because of the accumulation of fatty substances called plaques or atheromas. Atherosclerosis usually develops slowly. The process starts when the inner lining of an artery is damaged by either high blood pressure in the artery or a virus, an allergic reaction, irritants such as nicotine or drugs.
Low density lipoproteins (LDL) – plasma proteins that carry cholesterol, which is also defined as “bad cholesterol”, and blood cells often get stuck in the injured wall of the artery. To clean up this “mess”, specialised white blood cells move into the damaged area to gobble up fats and cholesterol.The blood cells may gobble up so much that they burst, causing more injury. Thus, the entire cycle repeats again.
As the damage grows, platelets – the cells in the blood that help blood to clot – recognise an injury and stick themselves to the injured area. One of the ways that platelets try to fix the injured artery is by instigating a relocation of muscle cells into the wall of the artery.
This thickens and stiffens the artery wall and causes further damage to the injured area. The thickened area is known as a plaque which gradually grows blocking the artery and reducing the blood flow through it. When that happens, more and more parts of the body begin to suffer from lack of oxygen. In time, the plaque can get larger and break open. When the rupture happens, a blood clot may form and block the flow of blood through the artery causing a stroke or heart attack.
What are the symptoms?
Atherosclerosis may develop unnoticed for many years before it causes symptoms. The symptoms may be constant or happen form time to time. They include:
❑ pain in the chest (angina)
❑ pain in the leg muscles when you exercise (intermittent claudication)
❑ dizziness
❑ a mini-stroke (transient ischemic attack, or TIA).
CVA – Stroke
Cerebrovascular Accident (CVA), better known as a stroke, is a serious medical condition which takes place when the blood supply to part of the brain is cut off that leads to the rapid loss of brain function. The oxygen and nutrients are needed for a proper function of the brain therefore when the supply of blood is disrupted brain cells begin to die. This might result in an inability to move parts of the body, understand or formulate speech.
There are three common types of strokes:
❑ Ischaemic (over 80% of all cases): the blood supply is disrupted due to a blood clot.
❑ Haemorrhagic: brain damage caused by the brain bursts due to a weakened blood vessel supply.
❑ Transient Ischaemic Attack (TIA) or a ‘mini-stroke’: a condition when the supply of blood to the brain is temporarily interrupted.
Coronary Artery Disease
Coronary Artery Disease (CAD) is the most common precursor of a heart attack. CAD is the hardening and narrowing of the coronary arteries by the buildup of plaque in the inside walls (also known as atherosclerosis). (Coronary arteries are those blood vessels that supply the heart itself with needed blood flow) Over time, plaque develops into a life threatening formation which can:
❑ Narrow the arteries so that less blood flows to the heart muscle
❑ Completely block the arteries and the flow of blood
❑ Cause blood clots to form and block the arteries
Heart Attack
Most heart attacks are caused by a blood clot which ends-up blocking one of the coronary arteries (the blood vessels that bring blood and oxygen to the heart muscle). When blood cannot reach a part of your heart, the area starves for oxygen. If the blockage continues long enough, cells in the affected area die. Learn more about arteriosclerosis risk factors.
A less common cause of heart attacks is a severe spasm (tightening) of the coronary artery that cuts off blood flow to the heart. These spasms can occur in persons with or without artery disease.
The cause of artery spasm can be:
❑ Emotional stress
❑ Exposure to cold
❑ Tobacco smoking
❑ Taking certain drugs, such as cocaine
Certain factors inrease the risk of arteriosclerotic development or even a heart attack. These risk factors can be put into two categories:
The biological risk factors (you cannot control)
❑ Having a family history of early heart disease (diagnosed in father or brother before age 55 or in mother or sister before age 65)
❑ Your own age (men: over age 45 or women: over age 55)
The health risk factors (you can control)
❑ Smoking
❑ High blood pressure
❑ High blood cholesterol
❑ Obesity
❑Being physically inactive
❑ Diabetes (high blood sugar)
Just like a skin wound, healing of the heart muscle begins soon after a heart attack. It takes about eight weeks: the heart’s wound heals and a scar will form in the damaged area. However, the new scar tissue does not contract therefore the heart’s pumping ability is lessened after a heart attack. The amount of lost pumping ability depends on the size and location of the scar.
Some people have a heart attack without having any symptoms .A “silent” myocardial infarction can occur in anyone, but it is more common among people with diabetes.