Why are there different treatments for each type of angina?

Angina is pain, discomfort or pressure in the chest, and doctors usually describe it as chronic stable angina or unstable angina.

• Chronic stable angina. Chronic stable angina is a form of chest pain that happens when your heart is working hard and needs more oxygen, such as during exercise. The pain goes away when you rest. In chronic stable angina, the pattern of chest pain is consistent, or stable, as far as how much physical exertion will trigger it. Your narrowed arteries can be the cause of this form of angina.

  If you have chronic stable angina, you may need angioplasty with stenting or medications as treatment. If the blockage causing chronic stable angina is severe, it's possible your doctor may recommend coronary bypass surgery. In this procedure, the blocked arteries are replaced with blood vessels grafted from another part of your body.

• Unstable angina. Unstable angina is either new chest pain or a change in your usual pattern of chest pain or discomfort — such as chest pain that is getting worse, lasting longer, or not being relieved with rest or use of medications.

  Unstable angina is dangerous and a warning sign of a heart attack. If your angina is unstable, seek urgent medical care. You may need hospitalization, adjustment of medications, angioplasty with stents or coronary bypass surgery.