Heart Transplantation

Heart transplantation is not a solution to all heart problems. In fact, it is suitable for only a few persons with only certain kinds of heart disease. The usual profile for a candidate for heart transplantation is age under 55 to 60 years, psychologically stable, and surrounded by a supportive family. All of the other vital organs must be in excellent health, particularly the kidneys, liver, and lungs. Most candidates for heart transplantation have suffered a widespread loss of functioning heart muscle (heart failure), either from repeated heart attacks or from cardiomyopathy.

How are you evaluated for a heart transplant?

You will meet with many specialists who help decide whether a heart transplant is the right treatment for you. The people you will meet, in addition to your primary doctor, are:

• A social worker: The social worker will ask questions about your schooling, work, childhood and life style. The social worker needs to know about any financial concerns and family support.
• Cardiologist (Specialist in heart diseases):  He or she will order the tests required. If you are accepted for a heart transplant, this is the doctor who will care for you before and after your transplant.
• Transplant coordinator will review the normal course of events that patients go through with heart transplantation. The coordinator schedules the required tests and reviews the results with your cardiologist. You will be followed by a coordinator throughout the evaluation process. If you are accepted for a transplant, a coordinator will follow you while you are on the waiting list and after transplantation
• Infectious disease physician: will check for any history of infections or any you may have now.
• Dentist: will check your teeth and gums to determine if they are healthy before transplant surgery.
• Dietitian: will look at your nutritional state.

You will also have a group of diagnostic tests:

1. Cardiac Catheterization: This test allows the doctor to examine the chambers, valves and arteries of the heart. Either the right or left side of the heart or both sides are catheterized. Blood samples are taken and pressures are measured during the catheterization.
2. Pulmonary Function Test: This is a study of the lungs to find out if your lungs are damaged.
3. MUGA Scan: This test determines the pumping function of your heart. A radioactive material is given into a vein and travels to your heart. A machine placed over your chest records the radioactive material in your heart.
4. Blood Tests: Many blood tests will be done to check how well your kidneys, liver, thyroid, and immune system work.
5. Echocardiogram: This is an ultrasound of the heart to look at the heart chambers and the valves.
6. Chest X-ray: This is a x-ray of your chest that shows heart size and lungs.

What do you expect while waiting for your transplant?

Before the operation, a donor heart must be found. Most often, this heart comes from the body of a healthy person who died in an accident but did not sustain heart injuries. In addition, the donor's relatives must give consent for the heart to be used for transplantation. The blood group of the donor must be the same as that of the recipient, and other characteristics of the donor’s and recipient’s tissues known as their tissue types must match as closely as possible.

When a matching donor becomes available, the transplant nurse coordinator will try to reach you on your home phone. If you do not answer or the line is busy, the coordinator will page you. The coordinator will instruct you to enter through the Emergency Department. The coordinator will tell you which hospital unit to go to. The transplant coordinator, your nurse, cardiologist, or a member of the surgical team will notify you of the possible transplant and time. Few donors are available, so relatively few people who are suitable for a heart transplant can actually be given one. Receiving a transplant depends largely on the good fortune of a suitable donor heart being available at the right place and at the right time.

Steps of the operation

1. As already mentioned, the donor heart is obtained from someone who has recently been pronounced brain dead, usually after an accident, but whose heart is healthy and is being kept functioning by artificial means. After removal from the donor, the heart and coronary arteries are washed and flushed out with a maintenance fluid. The heart is then packed in ice (above), where it can be preserved for several hours before it is inserted into the recipient.
2. An incision is made in the recipient’s breastbone, which is split apart, and the pericardium(sac covering the heart) is cut to gain access to the heart.
3. The patient is connected to a heart-lung machine, which takes over the function of the heart and lungs. Deoxygenated blood is removed from the patient via cannulas inserted into the venae cavae, oxygenated in the heart-lung machine, and then returned to the patient via a cannula inserted into the aorta.
4. The diseased heart is stopped by clamping the aorta; most of the heart is then removed by cutting through the walls of the upper heart chambers (atria) and the arteries to the lungs (pulmonary artery) and body (aorta). The back walls ofthe atria are left in place (right).
5. The donor heart is stitched to the free edge of the left atrium, the wall between the two atria, and the free edge of the right atrium.
6. To complete the main part of the operation, the patient's pulmonary artery and aorta are connected to the donor heart.
7. The surgeon then removes air from the heart chambers and removes the clamp on the aorta to restore a blood supply to the heart muscle. The heart is then started, usually by warming it; if this doesn’t work, the heart is started by applying an electric shock.
8. Finally, the surgeon checks for and repairs any small leaks from blood vessels, disconnects the patient from the heart-lung machine, and closes the chest.

Following a transplant operation, the patient is taken to the surgical cardiac intensive care unit and his or her condition is monitored for any signs of rejection of the new heart or for signs of infection. Immediately after the operation, the patient is connected to a ventilator to assist breathing and is under continuous electrocardiographic monitoring. Several drainage tubes are also placed inside the chest. These are removed or disconnected as recovery proceeds.

After being discharged from the hospital, the patient usually returns for heart muscle biopsies to check for any signs of heart tissue rejection. Most forms of physical activity can be gradually resumed under a doctor's directions.

What is Rejection?

All transplanted organs are susceptible to rejection. The body's immune system recognizes the transplanted tissue as foreign and produces antibodies to attack the "offender." In order to minimize the risk of rejection of a transplanted heart, you will be given drugs that suppress your body’s normal immune response. Some of these "immunosuppressive drugs" will be used for a short term and will be discontinued shortly after the operation. You must take others for the rest of your life. These drugs have side effects; they decrease your body’s ability to recognize and resist infectious disease. Therefore, dosages must be adjusted carefully.

Rejection is very common and in an attempt to diagnose rejection even before there is clinical evidence, you must undergo regular heart biopsy.  An Endomyocardial Biopsy (EMB) is the only way to test for rejection. The EMB takes about 30-45 minutes. You will be awake during the procedure and given a numbing medicine to the right side of your neck. The doctor will put a catheter or thin tube into a neck vein that will pass into the right ventricle of your heart. The doctor will then be able to obtain small pieces of tissue from your heart. This tissue is then sent to be examined by a pathologist for rejection. If there are no signs of rejection, you will just have a routine schedule for your biopsies. The biopsies will be more often if signs of rejection occur.

After you start your routine screening biopsies for rejection after your heart transplant, you will receive calls at home from the transplant coordinator about your biopsy scores. The score is from zero to 4, with zero means no rejection and 4 means severe rejection requiring hospitalization. Most rejection episodes can be treated successfully with medications, but sometimes when they are severe the patient’s circulation needs to be supported with a mechanical heart assist pump or even a second heart transplant.

To summarize, most successful recipients of heart transplants seem to recover to carry on relatively normal lives. Approximately 85 percent of those who have received heart transplants are alive and active 1 year after the operation; some have lived for more than a decade. Heart transplantation remains a complicated procedure. For success, this procedure requires well organized team of experienced transplantation specialists and a motivated recipient. If you have a transplant, you will continue to see members of the transplantation team for the rest of your life. They will carefully adjust medications and perform periodic heart biopsies to monitor rejection, and they will treat any complications. Transplantation is most appropriate in those cases in which it is the only hope for survival and the possibility of success is high.