Angina is a heart condition that happens when the blood supply to the muscles of the heart is restricted. It usually occurs when the arteries that feed the muscles of the heart become hardened and narrowed.
The main symptom of angina is a dull, heavy or tight pain in the chest that can sometimes spread to the left arm, neck, jaw or back. Unlike a heart attack (which is caused by more permanent blockage to the arteries and subsequent damage of heart muscle), the pain of an ‘angina attack’ is usually triggered by physical activity or stress and usually only lasts for a few minutes. The pain of a heart attack will usually last for about half an hour.
There are two main types of angina. These are ‘stable angina’ and ‘unstable angina’.
If your angina develops gradually and appears related to physical activity (such as climbing stairs) or stress, you are likely to have stable angina. Stable angina will usually last only a few minutes and can often be improved by taking fast-acting medication called glyceryl trinitrate (or GTN). GTN is usually sprayed underneath the tongue and works by opening up the arteries that feed the heart.
Stable angina is not immediately life-threatening, BUT, it is a serious warning sign that you are at risk of developing a more serious heart condition such as a heart attack or stroke.
Your angina is ‘unstable’ if your chest pain develops rapidly, occurs even without physical activity (for example, while sitting or resting) and can last for up to 30 minutes. Unlike stable angina, this kind of angina may NOT respond to treatment with GTN spray. In some cases, stable angina may worsen, and progress to unstable angina. In many people however, unstable angina may occur without any previous warning signs.
Unstable angina is a medical emergency because it is a definite sign that the function of your heart has deteriorated very rapidly, and that your chances of having a heart attack or stroke have been greatly increased. Unstable angina can be treated both with medication and with surgery.
Most cases of angina are caused by atherosclerosis, a condition in which the arteries that feed the heart become hardened and narrowed due to a build-up of fatty substances that are known as plaques. This reduces the blood supply to the muscle of the heart and triggers the symptoms of angina.
You are more likely to develop atherosclerosis if you are a male over the age of 50, a smoker, obese or eat a high-fat diet. You are also more likely to develop angina if you already have a history of heart disease, suffer with high blood pressure (or hypertension) or type 2 diabetes.
There are three main reasons why you MUST treat your angina:
- to relieve immediate symptoms of chest pain during an angina attack
- to reduce the number of angina attacks that you suffer in future
- to prevent the restricted blood supply to the heart from becoming more severe and causing a heart attack
Angina can be treated by using medicines, or surgery if the symptoms do not respond to drug treatment. The two main type of surgery used to treat angina are:
- a graft – where a blood vessel (usually a vein) is taken from another part of the body (usually the leg) and used to bypass the flow of blood past a blocked or narrow section of artery
- angioplasty – where a narrowed section of artery is widened using a tiny tube called a stent