Difference between coronary artery and just muscle spasm in chest?

Huge difference. Technically the heart is also a muscle but pain from the heart due to coronary artery disease is an extremely serious and potentially life threatening condition. Muscle spasms from the chest wall muscles are not common and are usually in response to some type of chest wall injury. If you are having pain in your chestthe first thing to do is see your doctor immediately or go to an er to check it.