If the pain is cardiogenic, and if nitroglycerine
relieves the pain, then the diagnosis of angina
is confirmed. Often there are co-factors, such as fatty deposits within the vessel. There, are, however many reasons for chest pain, including a physical injury to the sternum. What your brother needs is an in person consultation with a cardiologist, M.D. type, who, I am sure will prescribe appropriate tests and medications, if necessary.