Some people with chest pain find there is a problem with the musculature around the chest. Typically the pectoralis minor is the culprit and a tendonitis or a strain of this muscle can mimic angina and/or a heart attack by reproducing chest pain and pain radiating down the left arm.
The most common non heart related problem for chest pain is a dysfunction of a damaged joint in your spine and/or with one or more of your ribs. When the nerves leave your spine in the area of your chest, they follow a course along the underside of the rib and can cause pain anywhere along the way. Often the rib or vertebra (bone in the spine) is displaced from its proper alignment and can cause pain (sometimes terrible pain) at the sternum or breast bone.
Chiropractors are specially trained to determine the cause of non heart related chest pain and can treat this cause of the condition well.
Remember to see your cardiologist or general medical practitioner to be sure your heart is not causing your chest pain. If they clear you then seek out the help of a different type of practitioner that best fits your needs.