Stable angina is the most common type. It happens when the heart is working harder than usual. Stable angina has a regular pattern rest and medicines usually help.Unstable angina is the most dangerous. It does not follow that pattern and can happen without physical exertion. It does not go away with rest or medicine. It is a sign that you could have a heart attack soon.Variant angina(变异型心绞痛) is rare. It happens when you are resting. Medicines can help.