Median sternotomy is a type of surgical procedure in which a vertical inline incision is made along the sternum, after which the sternum itself is divided, or "cracked". This procedure provides access to the heart and lungs for surgical procedures such as heart transplant, corrective surgery for congenital heart defects, or coronary artery bypass surgery.
Median sternotomy is often mistakenly referred to as open heart surgery, in which it is a preliminary step. However, open heart additionally involves incision of the pericardium, and many median sternotomy procedures do not require this. Open heart usually involves the use of a cardiopulmonary bypass, also known as a heart-lung machine.
Should this procedure be performed upon an individual more than once, each subsequent sternotomy may be referred to as a "resternotomy".