After having a heart-lung transplant, one of the biggest risks is that your body will reject your new heart and lungs.

There is also a chance your new heart and lungs won't work properly, or you could develop serious infections because your immunosuppressant medication will weaken your immune system.

Rejection

Rejection can occur soon after transplant surgery, or several months or years later.

It doesn't always cause any obvious symptoms, but possible symptoms can include:

• fatigue (extreme tiredness)
• swelling of your arms and legs
• weight gain
• a high temperature (fever) of 38C (100.4F) or above
• heart palpitations (heartbeats that become more noticeable)
• shortness of breath
• coughing and wheezing

If you have any worrying symptoms, you should contact your transplant centre as soon as possible. Rejection can usually be treated by increasing your dose of immunosuppressant medication.

Bronchiolitis obliterans syndrome

Bronchiolitis obliterans syndrome (BOS) is a relatively common form of lung rejection that can occur in the years after a heart-lung transplant. In BOS, the immune system causes the airways inside the lungs to become inflamed, which blocks the flow of oxygen through the lungs.

Symptoms include:

• shortness of breath
• dry cough
• wheezing

It may be treated by giving you additional immunosuppressant medication.

Narrowing of the heart arteries

Although generally uncommon after a heart-lung transplant, sometimes the blood vessels connected to the donor heart can become narrowed and hardened. This is known as cardiac allograft vasculopathy or coronary artery vasculopathy (CAV).

CAV is potentially serious as it can restrict the supply of blood to the heart, which can sometimes trigger a heart attack or lead to heart failure. Because of this risk, you may have regular check-ups after your transplant to check whether your heart is receiving enough blood.

Treatment options for CAV include statins and calcium channel blockers (medication to help widen blood vessels).

Infections

Immunosuppressant medication will weaken your immune system and make you more vulnerable to infection, including bacterial, fungal and cytomegalovirus (CMV) infections.

Signs of a possible infection can include:

• a high temperature (fever) of 38C (100.4F) or above
• shortness of breath, wheezing or breathing difficulties
• generally feeling unwell
• sweating and shivering
• loss of appetite
• diarrhoea
• chest pain
• coughing up thick mucus that may be yellow, green, brown or bloodstained
• a rapid heartbeat
• dizziness
• a change in mental behaviour, such as confusion or disorientation

If you think you may have an infection, contact your GP or transplant team. Depending on the type of infection you have, you may need treatment with antibiotics, antifungals or antivirals.

Preventing infections

As a precaution, you may be given antibiotic, antifungal or antiviral medication for a few months after your transplant to protect you from serious infections.

You should also do what you can to reduce your risk of picking up an infection, particularly in the early stages of recovery. You should try to:

• avoid crowds
• avoid close contact with anyone you know who has an infection
• avoid anything that could damage your lungs and make them more vulnerable to infection, such as smoke, chemical sprays or chemical fumes
• practise good personal hygiene and ensure your house is kept clean

Read more about how to prevent germs spreading.