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.
Unstable angina is an emergency. It may mean that you are having a heart attack.
Unstable angina symptoms are similar to a heart attack. They may include chest pain or pressure that occurs at rest or with less and
less exertion. Symptoms may become severe and last longer. And they may not
respond to nitroglycerin or rest.
Unstable angina is a change from stable angina-a pattern of
predictable chest pain or other symptoms. Stable angina symptoms are relieved by rest or nitroglycerin.
Rakesh K. Pai, MD, FACC - Cardiology, Electrophysiology & E. Gregory Thompson, MD - Internal Medicine & Stephen Fort, MD, MRCP, FRCPC - Interventional Cardiology