A heart transplant is a surgical procedure performed to remove the diseased heart from a patient and replace it with a healthy one from an organ donor. In order to remove the heart from the donor, two or more doctors must declare the donor brain-dead.
Before a person can be put on a waiting list for a heart transplant, a doctor makes the determination that this is the best treatment option available for the person’s heart failure.
About the heart
The heart is the hardest working muscle in the human body. Located almost in the center of the chest, the adult human heart is about the size of one fist.
At an average rate of 80 times a minute, the heart beats about 115,000 times in one day or 42 million times in a year. During an average lifetime, the human heart will beat more than 3 billion times, pumping an amount of blood that equals about 1 million barrels. Even when a person is at rest, the heart is continuously hard at work.
How the heart works
The cardiovascular system, composed of the heart and blood vessels, is responsible for circulating blood throughout your body to supply the tissues with oxygen and nutrients.
The heart is the muscle that pumps blood filled with oxygen and nutrients through the blood vessels to the body tissues. It is made up of:
- Four chambers (two atria and two ventricles) that receive blood from the body (the atria) and pump out blood to it (the ventricles).
- The right atrium receives blood from the body, which is low in oxygen and high in carbon dioxide.
- The right ventricle pumps the blood from the right atrium into the lungs to provide it with oxygen and remove carbon dioxide.
- The left atrium receives blood from the lungs, which is rich in oxygen.
- The left ventricle pumps the blood from the left atrium into the body, supplying all organs with blood.
- Blood vessels, which compose a network of arteries and veins that carry blood throughout the body.
- Arteries transport blood from the heart to the body tissues.
- Veins carry blood back to the heart.
- Four valves to prevent backward flow of blood.
- Each valve is designed to allow the forward flow of blood and prevent backward flow.
- An electrical system of the heart that stimulates contraction of the heart muscle.
Reasons for the procedure
Heart transplantation is performed to replace a failing heart that cannot be adequately treated by other means.
Congestive heart failure (CHF)
End-stage heart failure is a disease in which the heart muscle is failing severely in its attempt to pump blood through the body, and in which all other available treatments are no longer helping to improve the heart’s function. End-stage heart failure is the final stage of heart failure. Heart failure, also called congestive heart failure, or CHF, is a condition that occurs when the heart is unable to pump blood sufficiently. Despite its name, a diagnosis of heart failure does NOT mean the heart is about to stop beating. The term “failure” refers to the fact that the heart muscle is failing to pump blood in the normal manner because it has become weakened.
Some causes of CHF, or weakening of the heart muscle, may include, but are not limited to, the following:
- Heart attack (also called myocardial infarction)
- Viral infection of the heart muscle
- High blood pressure (hypertension)
- Valvular heart disease
- Congenital (present at birth) heart conditions
- Cardiac arrhythmias (irregular heartbeats)
- Pulmonary hypertension (elevated blood pressure within the lungs’ blood vessels)
- Alcoholism or drug abuse
- Chronic lung diseases, such as emphysema or chronic obstructive pulmonary disease
- Cardiomyopathy (an enlargement of the heart muscle)
- Anemia (low red blood cell count)
There may be other reasons for your doctor to recommend heart transplantation.
Risks of the procedure
As with any surgery, complications may occur. Potential risks associated with heart transplantation may include, but are not limited to, the following:
- Bleeding during or after the surgery
- Blood clots that can cause heart attack, stroke, or lung problems
- Breathing problems
- Kidney failure
- Coronary arteriopathy (similar to coronary artery disease)
The new heart may be rejected by the body’s immune system. Rejection is the body’s normal reaction to a foreign object or tissue. When a new heart is transplanted into a recipient’s body, the immune system reacts to what it perceives as a threat and attacks the new organ, not realizing that the transplanted heart is beneficial. To allow the transplanted organ to survive in a new body, medications must be taken to trick the immune system into accepting the transplant and not attacking it as a foreign object.
The medications used to prevent or treat rejection have side effects. The exact side effects will depend on the specific medications that are taken.
Contraindications for heart transplantation include, but are not limited to, the following:
- Current or recurring infection that cannot be treated effectively
- Metastatic cancer. This is when cancer has spread from its primary location to one or more additional locations in the body.