Although receiving a donor heart can save your life, having a heart transplant has many risks. The most significant risk is your body rejecting the donor heart.

Rejection of the donor heart

Your immune system will see your donor heart as a foreign object that's not supposed to be in your body. Your immune system will try to attack your donor heart. Although all people who receive a heart transplant receive immunosuppressants — medications that reduce the activity of the immune system — nearly 25 percent of heart transplant recipients still have some signs of rejection during the first year after transplantation.

Usually the rejection is without any symptoms and requires only an adjustment of medications. If you miss doses of medications, however, the rejection can be severe and very serious. It's important that transplant recipients follow the instructions outlined by their doctors.

To determine whether your body is rejecting the new heart, you'll have frequent biopsies of the new heart for several months after your transplant. During the biopsy, a tube is inserted into a vein in your neck or groin and directed to your heart. A biopsy device is run through the tube to extract a tiny sample of heart tissue, which is examined in a lab.

Because rejection is most likely to occur in the first few months after heart transplantation, the frequency of heart biopsies is greatest during this early period. It's possible you'd have signs or symptoms that your body is rejecting your donor heart. These signs and symptoms could include:

  • Shortness of breath
  • Fever
  • Weight gain due to water retention
  • Not urinating as much as usual
  • Fatigue

Additional risks

Other risks after your heart transplant include:

  • Problems with your arteries. After your transplant, it's possible the walls of the arteries in your heart could thicken and harden, leading to cardiac allograft vasculopathy (CAV). This can make blood circulation through your heart difficult and can cause a heart attack, heart failure, heart arrhythmias or sudden cardiac death.
  • Medication side effects. The immunosuppressants you'll need to take for the rest of your life may cause serious kidney damage and other problems.
  • Cancer. Immunosuppressants can also increase your cancer risk. Taking these medications can put you at a greater risk of skin and lip tumors and non-Hodgkin's lymphoma, among others.
  • Infection. Immunosuppressants decrease your ability to fight infection. Many people who have heart transplants have an infection that requires them to be admitted to the hospital the first year after their transplant.
Jan. 27, 2015