A thoracic surgeon refers to a surgeon exhibiting a special training in operating organs within the chest, like the lungs and the heart.
Thoracic surgery also called cardiothoracic surgery refers to the branch of medicine that deals with the surgical treatment of organs present within the thorax, that is, the chest. Usually, the treatment of the conditions associated with lungs and heart comes under thoracic surgery and is performed by a specialist thoracic surgeon.