Complications
It is possible for heart transplant patients to present to the ED with vague and non specific complaints when in fact they have a life threatening illness. It is important to maintain a high index of suspicion for graft rejection, infection and graft vasculopathy, complications directly associated with cardiac transplantation or the drugs associated with transplantation.
Patients with transplanted hearts can also present with more conventional forms of cardiac disease such as heart failure, arrhythmias and ischaemia which will require assessment and appropriate ED-based intervention, some features of which have specific issues related to a transplanted heart.
Rejection
This most commonly occurs in the first year after transplant. Often the diagnosis is made on routine biopsy. The patient may look and feel well. When they become ill, they present with signs and symptoms of heart failure.
Problems related to immunosuppression [5]
Transplant patients are immunosuppressed. They are therefore susceptible to a range of organisms including ones which are predominantly encountered in the immunocompromised. These include candida, cytomegalovirus (CMV – image) and pneumocystis jirovecii pneumonia. CMV in particular is common following transplantation. It may present with constitutional symptoms, hepatitis, nephritis, pneumonitis or low platelets. The patient may not be overtly septic. They may be febrile, but this is not essential to the diagnosis of infection.
Pitfall: Immunosupressed patients may have an opportunistic infection without an associated fever.
The medications given to suppress the immune system post transplantation can cause a variety of adverse effects in addition to increased susceptibility to infection.
Adverse effects
| Steroids |
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| Cyclosporin |
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| Azathioprine |
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| Tacrolimus |
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Some drugs can increase the levels of immunosuppressants, increasing the risk of toxic effects. Alcohol, clarithromycin and calcium channel blockers can have this effect.
Other medications can lower immunosuppressant drug levels making them ineffective. Phenytoin and rifampicin are examples.
Learning bite
It is important to exercise caution when changing the treatment regime of a transplant patient. Liaison with the transplant team is recommended.
Ischaemia
Graft vasculopathy should be considered in patients presenting several years after a heart transplant. Ischaemia usually occurs without pain because the graft heart is denervated. The patient may present with heart failure, an arrhythmia or sudden death. The presentation may be non-specific with features such as breathlessness, sweating and nausea.
Pitfall: Cardiac ischaemia usually occurs without pain because the graft heart is denervated.
Malignancy [6]
An increased risk of malignancy is another side effect of immunosuppression. Incidence is 100 times greater in heart transplant patients than in the general population. Lymphoproliferative disorder is common, often with extranodal involvement. Diagnosis may be made on biopsy of the lymph node, bone marrow or endocardium.
Pericardial disease
A moderate or large pericardial effusion is common after transplantation. It is rarely sufficient to cause tamponade. Because transplant patients are at increased risk of infection and malignancy, one should have a low threshold for a diagnostic pericardiocentesis. Constrictive pericarditis may ultimately arise due to the effusion or any local infection, inflammation or haematoma. Post pericardiotomy syndrome may lead to constriction.