Angina is the discomfort or pain you feel, most likely in your chest, when your heart isn't getting enough oxygen. It's typically caused by narrowing of the arteries that carry blood to your heart. Doctors call this coronary artery disease.

But angina can be caused by other conditions that also stop your heart from getting enough oxygen. Here are some of those other conditions.

• You have problems with the valves in your heart.
• You have high blood pressure that hasn't been treated.
• You have a condition that doesn't have anything to do with heart problems but that makes your heart work harder. For example, if you have anemia, your blood doesn't carry enough oxygen. And if your thyroid gland is too active, your heart beats faster than normal. In both cases, your heart has to work harder, so it needs more oxygen. But it may not get as much as it needs to keep up.

This information is for educational use only, and is not a substitute for prompt professional medical advice. Readers should always consult a physician or other professional for advice and treatment. ©BMJ Publishing Group Limited 2008. All rights reserved.