The main risks of heart transplantation are infection and rejection.
Rejection
What is rejection?
Rejection is the body's way of responding to something it thinks does not belong in the body. Some rejection is expected after the transplant. Most rejection events are mild and your child may not have any signs of the rejection. Rejection of your child's new heart could happen at any time, but happens most often during the first year after the heart transplant operation.
There are different kinds of rejection. The most common type is called acute cellular rejection. There are more rare types of rejection that some patients are at higher risk of experiencing. If this is the case for your child, it will be explained to you by the Transplant team.
How can you tell if there is rejection?
A heart biopsy is one way to find out if your child's body is rejecting the new heart. This involves removing a small piece of heart muscle tissue for examination. Biopsies will be done regularly to check for rejection, though less often if your child is a newborn or infant.
What is immunosuppression?
Immunosuppressant medications are the medications given to stop your child’s body from rejecting the new heart. They are started in the operating room and your child will need to continue taking them for the rest of their life. The health of your child’s new heart will depend on them taking these medications exactly as they are prescribed every day. Although these are critical for the health of your child’s heart, they do have side effects which may need other medications to treat. All of these things will be explained and taught to you while your child is in the hospital. This will continue in the outpatient clinic visits.
What is post-transplant coronary artery disease?
Post-transplant coronary artery disease is another form of rejection. It is also known as chronic vascular rejection or graft vasculopathy. All patients after heart transplant undergo testing regularly to look for signs of coronary artery disease.
Blood is supplied to the heart by little blood vessels called coronary arteries. After transplant, for reasons not fully understood, the coronary arteries can become narrow and thick. This is not the same kind of coronary artery disease you may have heard about in adult patients with heart disease or heart attacks. There are no good catheter lab or surgical options to treat post-transplant coronary artery disease.
Important things to help slow down or prevent coronary artery disease include a heart-healthy diet, regular exercise, and taking all medications as prescribed, including immunosuppression, blood pressure, and cholesterol medications.
Some children may require another heart transplant if the coronary artery disease becomes severe enough.
Infections
Why is your child more likely to get infections than other kids?
Some parts of your child's immune system may be weaker because of the immunosuppressants she is taking for the new heart. Your child will get common illnesses, just like other children, that will not require any special treatment or precautions. However, certain infections may be more concerning in a patient who has had a transplant and require special monitoring or treatment. These infections include chickenpox, cytomegalovirus (CMV), and Epstein-Barr virus (EBV).
Information about this will be included in all of your post-transplant teaching and also provided to your family doctor or paediatrician after transplant.
How can infections be prevented?
To prevent infection, you should keep your child away from crowded places for the first 3 months after the operation. This means that your child will not be able to school, the movies, restaurants, or swimming pools where there are large crowds. Your child will also need to stay away from other children or adults who have a cold, a cold sore, the flu, or diarrhea.
What is post-transplant lymphoproliferative disease?
Post-transplant lymphoproliferative disorder (PTLD) is caused by an infection of the white blood cells in the body with Epstein-Barr virus (EBV). This virus lives in your body once you have had it but, in most people, the immune system keeps it under control. Patients on immunosuppressant drugs may have a more difficult time controlling this virus in the body, and it can cause the white blood cells to multiply out of control. This leads to varying stages of lymphoma, a type of cancer.
Any post-heart transplant patient is susceptible to this, so your child will be followed very regularly for the levels of EBV in the blood. They may require ultrasounds, X-rays, or other types of scans to look for tumours. If they do develop EBV, EBV disease, or any form of PTLD, they may require IV medications for many months to treat it. This can be administered at home. If the disease progresses, there may be a need for stronger forms of chemotherapy, but this is very rare.