In medicine, the field of cardiothoracic surgery is involved in the surgical treatment of diseases that affect organs inside the thorax (the chest). In general it will mean conditions of the heart (cardiovascular disease) and lungs (lung disease). Cardiothoracic surgery is a recognised surgical specialty.

Thoracic surgery generally refers to surgery of the chest other than the heart. A general surgeon may have an interest in thoracic surgery.

A cardiothoracic surgeon will perform Coronary Artery Bypass Graft (CABG), Heart valve, lung volume reduction, heart and/or lung transplantation, as well as arrhythmia surgery and thoracic aorta repairs.