Open heart surgery is defined as any type of surgery where the chest cavity is opened in order to access the heart. The chest is opened by cutting through the sternum, or breast bone. Rib spreaders may also be utilized to access the inside of the chest cavity. Individuals undergoing open heart surgery are commonly placed on a heart-lung bypass machine. Because it's difficult to operate on a beating heart, the heart is stopped, though blood flow, oxygenation and normal body organ function is continued through the use of the heart-lung bypass machine, which literally acts as a substitute for the heart during the procedure.

Another type of open heart surgery is called off-pump or beating heart surgery, which doesn't utilize a heart-lung bypass machine. This type of procedure is called off-pump bypass surgery, which utilizes heart stabilizers during the procedure, which include vein grafting that literally bypasses damaged pr blocked cardiac veins through the attachment of portions of good veins taken from other parts of the body. The stabilizers used in off-pump procedures are called an Octopus suction device because they utilizes suction cup activity and action much like that produced by an octopus. These suction cup devices hold one section of the heart still while the other portions of the heart remain functioning so that the surgeon can work on small portions of the heart at a time.