Conventional open-heart surgeries usually involve a full median sternotomy, in which the chest is opened, the heart stopped and blood re-routed through a heart-lung machine. However, there have been a number of advances in open-heart surgery, including procedures in which the heart is operated on without opening the chest, and/or the heart is allowed to continue beating (off pump coronary artery bypass [OPCAB]).

OPCAB surgeries in particular have become more popular. It is estimated that as many 20 percent of bypass surgeries performed in the United States in 2002 were OPCAB surgeries. These may be performed through a standard sternotomy incision, or through the use of smaller incisions. During an OPCAB, the heart is stabilized through the use of special devices and the heart-lung machine is not used. Although the use of heart-lung machines is routine, it has also been associated with a number of serious complications, such as a greater risk of heart attack or stroke.

Researchers have also developed surgeries that are performed through very small, “key hole” incisions in the chest. These are known as minimally invasive direct coronary artery bypass (MIDCAB for short) surgeries and have been performed on patients with comparatively mild forms of heart disease. Minimally invasive heart valve surgeries have also been performed on patients whose conditions may be too unstable for conventional open-heart surgery. MIDCAB procedures may be performed with or without the heart-lung machine.

Minimally invasive procedures offer a number of advantages over conventional open-heart surgery. They are less traumatic and require smaller incisions. However, not all patients are candidates for minimally invasive procedures. For instance, a MIDCAB is typically reserved for cases in which only one or two grafts are required, and treatment is often limited to blockages in the left anterior descending coronary artery (LAD).

Catheter-based procedures, especially balloon angioplasty with or without stent placement, are also decreasing the number of open-heart surgeries necessary. During a balloon angioplasty, the physician guides a thin plastic tube through the circulatory system and into the coronary arteries. When the catheter has reached the site of a blockage, the balloon is rapidly inflated, crushing the arterial plaque against the wall and opening up the vessel. In many cases, a stent is also implanted. A stent is a tiny metal mesh that is permanently left in the artery. Stents have been shown to reduce the incidence of restenosis, or reclosure of the artery, the reducing the need for further procedures. Catheter-based procedures can also be effective in treating heart-valve disease and certain congenital heart diseases, such as an atrial septal defect. Like minimally invasive procedures, catheter-based procedures offer a treatment option with less trauma and pain for the patient. However, these procedures also carry certain risks.