Types

• Angina is a form of chest pain that is the result of a heart condition, most commonly coronary artery disease. At its most basic definition, when blood flow to the heart is reduced, angina occurs. However, there are three types of angina, and each is caused by a different condition. These forms are known as stable angina, unstable angina and variant angina.
  
  

Stable Angina

• When a patient's arteries are narrowed due to atherosclerosis (the buildup of plaque and other fatty deposits), stable angina occurs when the person exerts himself. The added strain on the heart and the difficulty in pumping blood through the arteries creates the pain of angina.
  
  In addition to physical activity, other factors such as stress, extreme changes in temperature, consuming a large meal or regular smoking have been shown to cause stable angina. Symptoms associated with stable angina typically cease when the person resumes resting or takes medications to control angina symptoms.
  
  

Unstable Angina

• Unstable angina occurs as the result of blood clots that develop in an artery. Portions of plaque on the artery can loosen and break off, creating a blood clot in the vein. This blockage prevents blood flow to the heart and causes angina symptoms. This condition can also occur in those who have severe anemia, and therefore already have a reduced amount of blood flow.
  
  This type of angina is especially dangerous because the clot can completely block the artery, which can result in a heart attack. However, other clots may form periodically and then dissolve over time without causing heart attack. While other angina forms can typically be controlled with rest or medications, unstable angina requires emergency medical attention.
  
  

Variant Angina

• This form of angina is also known as Prinzmetal's angina. Variant angina has less to do with the plaque inside the veins and more with the veins themselves. Those with variant angina experience spasms in the arteries, which cause blood flow to repeatedly stop and start. This angina type accounts for only a small percentage of diagnosed angina cases, according to the Mayo Clinic.
  
  Spasm causes include exposure to extreme cold, stress, certain medications, smoking or cocaine use, according to the National Heart, Lung and Blood Institute.