Experience Journal: Pediatric Heart Disease

Pediatric Heart Transplantation:
A Practical Parent Guide

PART 7: SELECTED ISSUES AFTER TRANSPLANT

REJECTION

Rejection is a normal reaction of the body to a foreign object. When a new heart is placed in your child’s body, the body sees the transplanted organ as a threat or foreign and tries to attack it. The immune system is responsible for the body’s defense against infection (such as bacteria or viruses) or foreign tissues (such as transplanted organs). Thus a heart transplant is viewed by the body’s immune system as foreign. The body mounts an attack against the transplanted heart by sending cells from the immune system to destroy the new heart. This attack is called rejection. We can identify that rejection is occurring by looking for the cells in small pieces of the heart muscle under a microscope. We see swelling or inflammation around the heart’s muscle cells.

Following transplantation, immunosuppressive medications (medicine to decrease your child’s immune response) are used to prevent the immune system from rejecting the new heart. As described in the previous section, the current protocol calls for two induction or short term medications (Thymoglobulin and steroids) and two routine medications: tacrolimus (Prograf/FK506) and mycophenolate Mofetil (Cell Cept). Medicine to prevent rejection will be needed for the rest of your child’s life.

Rejection of a transplanted organ will occur at unpredictable times following transplant. The chance of rejection is highest in the first few months after the heart transplantation. The first year following your transplant is the time period when we are working to establish the best combination of anti-rejection medications. Nearly every patient will have at least one rejection episode. Your child will be no exception.

Your child may experience rejection, but have no observable symptoms. Your child can look well. However, generally there is some evidence with your child experiencing at least some the following possible symptoms: fatigue, irritability, shortness of breath, difficulty breathing, fast heartbeat, irregular heartbeat, poor eating, decreased appetite, nausea, vomiting, diarrhea, and/or fever. If your child has any of these symptoms occur, we assume that there is rejection occurring until proven otherwise.

Making the Diagnosis of Rejection

Rejection can be identified at routine clinic visits as well as when symptoms suspicious for rejection occur. A number of tests are performed to help identify rejection, determine effect on the transplanted organ and formulate treatment of rejection.

Cardiac Biopsy is presently the most reliable means of diagnosing rejection. It is performed at times when rejection is suspected, but also to check for rejection even if there are no other signs. Biopsies are done frequently in the early months after transplant when the chance of rejection is highest. Fewer biopsies are needed after the first year.

A cardiac biopsy is a type of heart catheterization that can be done as an outpatient procedure in the cardiac catheterization lab. Your child is given a sedative, if needed, and a local anesthetic. A catheter is inserted into a vein (usually in the neck or leg) and directed by x-ray (fluoroscopy) into the chambers of the right side of the heart where pressures are measured. Then a special catheter with tiny tweezers on the end is put through the catheter and tiny samples of heart muscle are obtained. The catheter is removed and your child can return to the catheterization recovery room. The biopsies are processed and results are obtained several hours after the procedure.

Echocardiogram obtains information regarding heart muscle function and swelling as well as heart valve function. Fluid collections around the heart called pericardial effusions can also be detected. Problems in these areas are indications of rejection.

An echocardiogram is a type of ultrasound that does not cause any discomfort or pain. First, a special gel is placed on your child’s chest or stomach area. Next a small transducer, which looks like a small box with a rubber cover, is placed over the gel directly on your child’s chest, stomach, and towards his/her neck. The transducer is gently moved in many directions to both see the various parts of your heart, but also to see the direction and speed of the blood as it travels around your heart. The test takes approximately 45 minutes to 1 hour to perform. It is performed either in the cardiology clinic or in the catheterization recovery room.

Managing and Treating Rejection

If your child’s biopsy shows rejection, our treatment response will be determined by the time since transplant and severity of rejection. We often treat rejection episodes in the first few months after transplant by hospitalizing your child for high IV doses of immunosuppressive medication. Rejection episodes later in the transplant course may be treated with an increase in your child’s oral Prednisone dose for several days and then a gradual decrease over several days to the usual dose (called a Prednisone taper). If the rejection is recurrent or more severe, additional immunosuppression may be necessary. Re-admission to the hospital for control of a rejection process is sometimes necessary.

We monitor children closely during rejection episodes. They may have signs of worsening heart function and/or side effects of the immunosuppressive treatment. Cardiac biopsy will always be repeated following a rejection episode to see if the treatment was successful or if more treatment is needed.

Our goal is to give patients adequate immunosuppression to prevent rejection but use the lowest doses possible to prevent side effects. Since every patient is different, finding a good balance takes some time and many medication adjustments may be needed in the first few months.

INFECTION

Since children who undergo heart transplantation require medications that decrease their body’s immune system, they are at higher risk for infection. To some degree, your child will always be at higher risk of infection. However, your child will be at the highest risk early after transplantation when he/she is on the highest doses of immunosuppressive medications.

The signs of an infection are similar to rejection in that your child may develop: fever, cough, irritability, diarrhea, and/or vomiting. The wound from surgery may be red, swollen, and draining.

Making the Diagnosis of an Infection

Diagnosis is often made from examining your child as well as conducting a variety of tests including blood work, chest x-rays, and/or urine studies. Because post transplant patients can get rare or uncommon infections, we will work with your primary physician to help arrange infection work-ups.

Treating an Infection

Treatment is based on severity of symptoms and the cause of infection. Early post transplant patients are often admitted to the hospital for both the evaluation of infection and treatment.

POST TRANSPLANT LYMPHOPROLIFERATIVE DISEASE (PTLD)

PTLD is a rare complication after a heart transplant. It is a type of cancer found only in those patients who have received a transplant. It is an abnormal response from the immune system secondary to the chronic immunosuppression caused by a patient’s medications. The immune system produces abnormal cells and forms solid collections of the abnormal cells, usually in a patient’s lymph nodes. This problem generally presents with the development of swollen, tender and hard lymph nodes. The diagnosis is made by biopsy of the suspicious lymph node. Treatment is often removal of the suspicious lymph nodes followed by decreasing anti-rejection medications. Some patients require the use of chemotherapy.

CORONARY ARTERY DISEASE

Coronary artery disease or “graft atherosclerosis” is another complication after heart transplant. The coronary arteries are small vessels that sit on the outside of the heart and deliver blood with oxygen to the heart muscle. Swelling can occur inside these small arteries. The swelling causes a decrease in blood flow through the vessels, therefore less blood is delivered to the heart muscle. The heart muscle can suffer damage if there is not enough blood flow. The cause of the swelling or narrowing is not clear but is thought to be a type of rejection inside the vessels.

Your child will have tests each year to identify subtle changes in the coronary arteries. Because post transplant coronary artery disease is thought to be a form of rejection, patients that have signs of post transplant coronary artery disease will be on higher doses of immunosuppression. In attempts to prevent coronary artery disease, your child will be instructed on the importance of a routine exercise regimen and a diet low in cholesterol. Cholesterol lowering agents may also be recommended.