Our Health Library information does not replace the advice of a doctor. Please be advised that this information is made available to assist our patients to learn more about their health. Our providers may not see and/or treat all topics found herein.

Unstable angina

Unstable angina is a change in your usual pattern of stable angina. Your symptoms do not happen at a predictable time. For example, you may feel angina when you are resting. Your symptoms may be more frequent, severe, or longer-lasting than your usual pattern of stable angina. Your symptoms may not go away when you try your typical ways of relieving them, such as rest or nitroglycerin.

Unstable angina is an emergency. It may mean that you are having a heart attack.

Unstable angina happens when blood flow to the heart is suddenly slowed by narrowed vessels or small blood clots that form in the coronary arteries.