However, despite its frequency in diagnosis, information on angina can be confusing and often misleading — especially when outlining the differences between stable and unstable angina. To make things a little clearer, we’ll take a look at what angina is, the different types and what you can do to reduce your risk.
What is angina?
While there are different types of angina, the condition, in general, is caused by restricted blood flow to the heart. When the blood vessels leading to the heart are partially blocked, the blood flow to the heart muscles is reduced, leading to uncomfortable chest pain.2 Those who experience angina tend to describe this as a heavy pain felt in the centre of the chest. These symptoms may also travel to the jaw or down the left arm. Nausea, heavy sweating and shortness of breath are also common signs of angina in any form.
What are the main risk factors of angina?
Angina is a symptom of cardiovascular disease (CVD), which occurs when the arteries to the heart become blocked by fatty plaques in their walls, meaning that less blood can pass through them. The risk factors for CVD include smoking, excessive alcohol intake, being overweight or obese, high cholesterol and diabetes. While many of these are changeable lifestyle factors, relating to diet and weight, some patients will have a genetic predisposition to diabetes, high cholesterol and heart disease, even if they are non-smokers and lead a healthy, active lifestyle. In general, men tend to be at higher risk than women of being diagnosed with angina. This risk also increases with age and with certain ethnic origins, particularly for those from South Asia.3
Alongside health and lifestyle factors, there are also a number of medical conditions that can increase the risk of angina. High blood pressure, atrial fibrillation (which is often picked up when an irregular heartbeat is noticed), chronic kidney disease, rheumatoid arthritis, lupus and other inflammatory conditions all place us at a higher risk of CVD, leading to angina.4
Unstable vs stable angina: what are the differences?
Stable and unstable are terms used to describe the severity of angina. With stable angina, chest pain is temporary, often occurring with exercise and always going away with rest. It’s a serious medical condition that needs investigating, but with less urgency than unstable angina. If a patient visits their GP with symptoms of stable angina, the typical protocol would be to start them on aspirin (and possibly other drugs such as beta-blockers) and prescribe them a nitrate spray to use when the next attack occurs. In the long-term, they would undergo blood tests to outline their risk factors and be referred to a rapid access chest clinic. Services vary across the country but most rapid access clinics will see patients within two weeks.5
In most cases, unstable angina will develop in patients who have previously been diagnosed with stable angina. However, in some cases, a diagnosis of unstable angina may be the first presentation of cardiovascular disease. With unstable angina, attacks are much less predictable and not always brought on by exercise. The patient may experience chest pain simply when they are sitting still, or it may occur as a result of exercise, but it will not subside with rest. If a patient presents symptoms of unstable angina, they need to be transported to a hospital immediately via a blue-light ambulance, where they will often be admitted to prevent its progression to a heart attack.
What health problems can angina cause?
Given the increased severity, patients diagnosed with unstable angina are placed at greater risk of developing health problems as a result of their condition. However, in both cases, angina can lead to a heart attack if left untreated.6 This is because, over time, a blood clot can develop in the clogged blood vessels, causing the heart to become completely starved of blood. In this case, the patient will require emergency treatment, either through thrombolysis (drugs to dissolve the clot) or angioplasty (removal of the clot by a wire inserted into the arteries around the heart).7
Patients with heart disease will also often have damage to other blood vessels in the body, which places them at more of a risk of peripheral vascular disease — a blockage of the blood vessels in the leg, causing pain and swelling in the calf. Additionally, angina places patients at a higher risk of stroke due to a similar process occurring in blood vessels in the brain.
What can I do to minimise my risk of getting angina?
While angina can lead to a number of health conditions if left untreated, there are a number of health and lifestyle changes that can significantly reduce your risk of an attack, for both stable and unstable angina.
Increase exercise and lose weight
High blood pressure, diabetes and high cholesterol are closely linked to obesity. As such, to reduce the risk of angina, losing weight should be considered as an option with those who are overweight. While some people find calorie counting effective, there is increasing evidence that a low glycaemic index diet can be an effective way of losing weight and can reduce the risk of diabetes (or put existing diabetes into remission).8 On top of this, regular exercise can reduce the risk of heart disease, as well as decreasing your chances of developing depression, cancer and dementia.10 If you've never exercised before, consider using a couch to 5k app to get you started.
The risk of heart disease will halve within a year of stopping — and by 15 years smoke-free the risk of a heart attack is the same as that of someone who has never smoked. There are a number of useful and informative NHS services that can help get you on the right tracks.9
Keep an eye on your blood pressure and cholesterol
A good measure to take when maintaining your overall heart health, but especially when considering angina, is to keep a regular check on your blood pressure. Get your blood pressure and cholesterol checked at the age of 40 and take your GP’s advice if it is high. This can be done by having a free NHS Health Check with your GP.11 One way of managing your cholesterol levels naturally is through nutrition. See our guide to regulating cholesterol with krill oil for more information.
For more information on arrhythmia and a range of other heart conditions, visit our heart health hub, where you’ll find a number of articles to help you maintain a healthy heart.
1Heart UK (no date). Key facts & figures, Heart UK
2NHS (2018). Angina, NHS UK
3CKS (2014). CVD risk assessment and management, Clinical Knowledge Summaries
4Public Health England (2017). Action plan for cardiovascular disease prevention, PHE
5UCLH (no date). Rapid access chest pain clinic, UCLH
6NHS (2016). Heart Attack, NHS UK
7BHF (no date). Focus on: Heart attacks, British Heart Foundation
8Stentz, F.B., et al. (2016). Remission of pre-diabetes to normal glucose tolerance in obese adults with high protein versus high carbohydrate diet: randomized control trial, BMJ Open Diabetes Research and Care
9NHS (no date). What happens when you quit?, NHS UK
10NHS (2018). Exercise, NHS UK
11NHS (no date). NHS Health Check, NHS UK