An Overview of Angina

Symptoms, Causes, and Types

Angina. Science Photo Library/Getty Images

Angina refers to the symptoms (usually chest pain or chest discomfort) that occur when some part of the heart muscle is in a state of ischemia. Ischemia means that a tissue is not receiving enough oxygen to function normally, usually because its blood supply is insufficient.

The ischemia that produces angina typically occurs because atherosclerotic plaques associated with coronary artery disease (CAD) are obstructing blood flow to part of the heart muscle.

What Does Angina Feel Like?

While angina is most commonly described as chest pain, it is not always in the chest, and it is not always painful. Angina can be felt in the chest, back, neck, shoulders, arms, and/or the abdomen. And many people with angina will describe - instead of "pain" - a pressure-like sensation, or squeezing, choking, numbness, or almost any other type of discomfort. Angina can be mild enough to brush off as "nothing," or so severe that it stops you in your tracks.

In women, angina is particularly likely to be "atypical" in the way it feels.

But because it indicates that a portion of the heart muscle is at risk, angina is always a serious matter, whether it is mild or severe.

Angina Due to Coronary Artery Disease

In patients with CAD, cardiologists describe two distinct syndromes: stable angina  and unstable angina.

Stable angina occurs in a reasonably predictable and reproducible manner, generally during an episode of exertion, stress, or some other situation where the heart is clearly working a bit harder than usual.

Stable angina occurs because a plaque is partially obstructing a coronary artery  so that the muscle supplied by that artery becomes starved for oxygen during periods of increased cardiac work.

Unstable angina, on the other hand, is unpredictable and non-reproducible.

It is a form of acute coronary syndrome (ACS), which means it is associated with the rupture of a plaque. Here , the angina occurs because the plaque itself is unstable, with the amount of obstruction varying from minute to minute depending on the amount of spasm and blood clotting associated with the plaque rupture. Unstable angina is just as likely to occur during complete rest as it is with exertion. Unstable angina is a medical emergency and must be treated immediately to prevent permanent heart damage.

Other Causes of Angina

Angina may also occur for reasons other than typical CAD, though more often in women than in men. Read about these "atypical" causes of angina:

Other Causes of Chest Pain

Not all chest pain is angina. In fact, it is probably true that most chest pain is not angina. Read about the many causes of chest pain, and how to tell whether it may be angina or not:


Fihn SD, Gardin JM, Abrams J, et al. 2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/STS guideline for the diagnosis and management of patients with stable ischemic heart disease: executive summary: a report of the American College of Cardiology Foundation/American Heart Association task force on practice guidelines, and the American College of Physicians, American Association for Thoracic Surgery, Preventive Cardiovascular Nurses Association, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. Circulation 2012; 126:3097.

Continue Reading