Please note that this article is not comprehensive and neither is it formal medical advice.
Angina is a symptom that is brought on when the heart doesn't get enough blood. It occurs on exertion and is classically described as left sided chest pain which is "heavy", "tight" or "like an elephant sat on the chest". It may spread to the arms, neck or jaw. In fact, its nature can vary patient to patient. It can be located anywhere in the chest and sometimes, it is not chest pain but is breathlessness or tiredness. Although angina varies between patients, its character rarely changes in an individual unless they have had coronary bypass surgery or are diabetic.
The most common cause is coronary disease where narrowings have developed in the arteries that supply the heart with blood. Apart from exertion, angina can be triggered by factors which reduce the blood supply to the heart such as anaemia or which make the heart work harder such as cold and windy weather.
When angina is stable, it occurs after a predictable amount of exertion and goes quickly with rest. GTN, a drug administered under the tongue, also provides rapid relief.
It is important that patients can distinguish a heart attack from stable angina. When angina occurs, patients should rest and if it does not go quickly, GTN should be taken every 5 minutes until it is gone. If it is still there after 15 minutes regardless as to whether GTN has been taken, an ambulance should be called for as a heart attack is likely.
Unstable angina may precede a heart attack. This is when angina occurs at rest or comes on with less exertion than usual. Urgent medical attention should be sought.
In broad terms, this is caused by the deposition of fat in the walls of the coronary arteries. Remarkably, the first evidence for this is seen in childhood. However, symptoms do not usually develop until middle age although patients with familial hyperlipidaemia present earlier.
The long time interval between onset of disease and onset of symptoms is an opportunity to prevent the disease from progressing.
This is when measures are taken to prevent clinical disease from developing.
It is extremely important for smokers to stop.
With diet, it is best to replace saturated fats, whole milk and red meat with low fat spreads, vegetable oil, skimmed milk and white meat. A healthy balanced diet includes plenty of fruit, vegetables and starchy food. Being overweight should be avoided.
Exercise is also important and walking 30 minutes a day is a good start.
Primary Prevention & Statins
There are "cardiovascular risk calculators" which estimate an individual's risk e.g qintervention.org. These are not precise. For instance, if there are a 100 people with a 10% risk over 10 years, it would not be possible to identify the 10 that will develop disease and the 90 that won't. However, the calculators can also estimate the benefits of stopping smoking, taking a statin, treating high blood pressure etc as well as the chances of statin side effects occurring and all this information can help people decide what preventative steps they want to take.
When the sink is draining slowly, the drainage pipe is at least 75% blocked. Similarly, when angina develops in coronary disease, this indicates a significant narrowing.
Secondary prevention is when treatment is given to prevent clinical disease from getting worse e.g. to prevent heart attack or death in someone with angina.
In this situation, the use of risk calculators is not appropriate as all patients are at high risk and all should be considered for aspirin, statins and other drugs such as ACE inhibitors.
If a soaker pipe becomes blocked, the number of plants at risk depends on how close the blockage is to the tap.
The heart has 3 coronary arteries and their "tap" is the aorta through which all blood leaves the heart. Investigations such as cardiac catheterisation and cardiac MR give information about the number and location of blockages as well as the amount of cardiac muscle at risk.
In addition to secondary prevention, drugs are used to prevent angina. These include beta blockers and nitrates.
Stents can also be inserted in order to open up the coronary arteries for symptom relief.
Depending on the severity of disease, patients may require coronary bypass surgery in order to live longer.
In summary, both coronary disease and angina can be prevented. If angina does develop, quick assessment is necessary to prevent heart attack and death.