Angina is caused by reduced blood flow to the heart muscles as a result of Coronary Artery Disease (CAD). CAD causes narrowing of the artery, which at rest still allows sufficient oxygenated blood to the myocardium (heart muscle). However, during exercise or stress, coronary oxygen demand increases but is unable to be delivered sufficiently through the narrowed coronary arteries.
The pain or discomfort can be:
- Be felt across or in the centre of the chest
- Radiate to one or both arms, the neck, back
- Be felt above the belly button and below the sternum
- Be accompanied by belching
Angina can be classed as stable Angina if the pain or discomfort presents as above and is brought on as a result of extertion or stress but relieved by the persons medication or rest. The medication is called GTN (glyceryl trinitrate) and is a vasodilator, so dialtes blood vessels improving the blood flow to the heart muscle. The person should spray a single does under their tongue, wait five minutes and then take a second dose. If the pain persists for a further 5 minutes and ambulance should be called.
Unstable Angina means that the pain or discomfort is brought on without exercise or stress, so occurs with minimal exertion.