Bypass surgery

If the coronary arteries are blocked, bypass surgery bridges the narrowings so that the heart is supplied with enough blood again. About 50,000 bypass operations are performed in Germany each year. Expert tips from Dr. Alexander Hierl.

Bypass surgery is a method for treating circulatory disorders. Bypass means "detour". It is used to bridge narrowed vessel segments. Bypasses can in principle be placed in various regions of the body; cardiac bypass surgery is the best known.

Narrowing of the coronary arteries as the cause

The cause of reduced blood flow to the heart is usually narrowing of the coronary arteries, known as coronary artery disease (CAD). This can trigger angina pectoris or produce abnormal findings in routine tests such as an exercise ECG.

The severity of the disease is determined by cardiac catheterisation or coronary CT. Depending on factors such as the patient's age, concomitant diseases such as diabetes, the severity of CAD and the location of the stenoses, the cardiologist, cardiac surgeon and patient must then decide whether and which treatment should be used. The usual options are drug treatment, an intervention with cardiac catheterisation and stent implantation, or bypass surgery.

How the operation is performed

In this operation, first performed in Cleveland in 1967 and now routine, one or more vessel grafts are usually placed between the aorta and the coronary arteries. The operation therefore lasts between two and five hours. Arteries such as the internal mammary artery (A. mammaria) or a radial artery (A. radialis), or leg veins (V. saphena magna), are used as grafts; the best results are achieved with the A. mammaria. In rare cases artificial vessel prostheses are also used.

In classic bypass surgery the chest is opened (sternotomy) and the heart is stopped during the procedure. A heart-lung machine maintains the circulation during this time, oxygenates the blood and removes carbon dioxide. A gentler but not yet generally established method is surgery on the beating heart without a heart-lung machine (OPCAB), but still with sternotomy. In rare cases, if only a coronary artery on the anterior wall of the heart is affected, sternotomy can be omitted and a small incision between the ribs is enough to place the bypass (MIDCAB).

Aftercare

After the operation, patients usually spend one day on the intensive care unit and about one week in hospital in total before going to a rehabilitation facility. There, drug therapy is adjusted and mobilisation and physical training are started under supervision; this should be continued at home in a cardiac sports group. Further care is provided by the office-based cardiologist in close cooperation with the family doctor.