Angina is chest pain or discomfort that occurs when there is not enough blood flow to the heart. Angina may also cause pain in the shoulders, arm, neck, jaw or back. Angina is often a symptom of coronary artery disease (CAD), the most common form of heart disease. It can also be caused by cardiomyopathy, aortic stenosis and many other conditions. Not all chest pain or discomfort is angina. Your physician will run tests to determine the underlying cause.