Causes of Angina Include Coronary Heart Disease, Coronary Microvascular Disease, and Blood Clots

There are several causes of angina, a type of chest pain that is the result of reduced blood flow to the heart. Most commonly, this reduction in blood flow is caused by coronary heart disease, although it can also be caused by blood clots, coronary artery spasms, and coronary microvascular disease. Direct causes of these heart conditions (e.g., smoking, high cholesterol, high blood pressure and high blood sugar levels) are often considered indirect causes of angina.

While several cardiac conditions can cause a drop in blood flow to the heart, the associated chest pain often occurs in brief episodes that are the result of a specific trigger. This is classified as stable angina. Stable angina episodes can be caused by:  

  • Physical exertion
  • Stress
  • Exposure to extreme heat or cold
  • Use of tobacco products
  • Large meals

When angina attacks occur without a specific trigger, they are classified as unstable angina. Unstable angina is often caused by a blockage in a coronary artery. This can be a sign that a heart attack is about to occur and should be treated as a medical emergency.

Other, less common types of angina can have different causes. For instance, variant (Prinzmental’s) angina is caused by spasms in the coronary arteries. These spasms can be triggered by stress, cold weather, smoking, and illicit drug use. Microvascular angina is caused by coronary microvascular disease, in which the inner walls of the small blood vessels that branch off from the coronary arteries become damaged and cause the vessels to spasm and reduce blood flow to the heart. For a referral to a cardiologist, use our PhysicianFinder.