Angina pectoris is due to myocardial ischemia and the diagnosis is made by the patient's history. It is typically described as a substernal discomfort that is provoked by factors that include heart rate and blood pressure such as physical exertion or emotional stress. It usually has a duration of several minutes and is relieved by rest or nitroglycerin.

Many patients do not perceive the discomfort of angina pectoris as pain. They commonly describe the character of their symptoms as a diffuse pressure or tightness. Other descriptors include heaviness, aching, distress, fullness, squeezing, indigestion, burning and numbness.

There are also certain descriptions that are not likely to reflect angina pectoris, including sharp, stabbing, focal pain of sudden onset that lasts a few seconds.

The location and radiation of the symptoms of angina pectoris are also variable. While typically substernal, other locations and/or areas of radiation include the jaw, shoulders, back, arms, wrists and epigastrium.

Precipitating factors in addition to exertion include emotional upset, large meals and exposure to cold. The common denominator is an increase in myocardial oxygen demand caused by an increase in heart rate, contractility and/or systolic blood pressure.

Although the quality and location of the symptoms of acute myocardial infarction may be similar to angina pectoris, acute infaction is characterized by discomfort that is typically , of sudden onset and usually lasts more than thirty minutes. Symptoms often occur at rest and may be associated with nausea, vomiting and diaphoresis. The diagnosis of myocardial infarction is established by documenting myocardial necrosis. With myocardial infarction there are often associated ST and T wave changes on the electrocardiogram and a rise in serum biomarkers.