There are different types of angina as listed below: Stable Angina This is the most common form of angina. It can occur to anyone under stress, or after strenuous physical activity. Stable angina can last for few minutes and subsides after you take rest. It is not a heart attack but it is a sign that you are at an increased risk of having one. Unstable Angina This type of angina can occur at rest and its symptoms are recurrent. It is an indication of a heart attack happening at any time soon. Consult your doctor right away to deal with it. Prizmetal's Angina: This is a rare form of angina that occurs at night or during sleep. Contraction and tightness of arteries involved in this ca lead to severe pain and discomfort. Getting it treated is necessary to avoid further damage. It is also called variant angina.