Although heart-transplant surgery is a life-saving measure, it has many risks. Careful monitoring, treatment and regular medical care can prevent or help manage some of these risks.
Risks of heart transplant include:
- Failure of the donor heart
- Complications from medicines
- Problems that arise from not following lifelong health-care plans
Failure of the donor heart
Over time the new heart may fail due to the same reasons that caused the original heart to fail. Failure of the donor heart also can occur if the body rejects the donor heart or if blood-vessel disease develops in the new heart and causes it to fail. This blood-vessel disease is called cardiac allograft vasculopathy (CAV).
Patients who receive a heart transplant that fails can be considered for another transplant (called a retransplant).
Primary graft dysfunction
The most frequent cause of death in the first 30 days after transplant is when the new donor heart fails and isn't able to function. This is called primary graft dysfunction. Factors such as shock or trauma to the donor heart or narrowed blood vessels in the recipient's lungs can cause primary graft dysfunction. Medicines (for example, inhaled nitric oxide and intravenous nitrates) may be used to treat this condition.
Rejection of the donor heart
Rejection is one of the leading causes of death in the first year after transplant. The recipient's immune system sees the new heart as a "foreign body" and attempts to destroy or reject it. During the first year, 25% of patients have signs of a possible rejection at least once. Half of all possible rejections happen in the first 6 weeks after surgery, and most happen within 6 months of surgery.
Cardiac allograft vasculopathy
CAV is a chronic (ongoing) disease in which the walls of the new heart's coronary arteries become thick, hard, and lose their elasticity. CAV can destroy the circulation of blood in the donor heart and cause serious damage.
CAV is a leading cause of donor heart failure and death in the years following transplant surgery. It can cause heart attack, heart failure, dangerous arrhythmias and sudden cardiac arrest.
Complications from medicines
Taking daily medicines that stop the immune system from attacking the new heart is absolutely critical, even though the medicine combinations have serious side effects.
Cyclosporine and other medicines can cause kidney damage. Kidney damage affects more than 25% of patients in the first year after transplant. Five percent of transplant patients will develop end-stage kidney disease in 7 years.
When the immune system—the body's defence system—is suppressed, the patient is at increased risk for infection. Infection is a major cause of hospital admission for heart transplant patients and a leading cause of death in the first year after transplant.
Suppressing the immune system leaves patients at risk for cancers and malignancies. Malignancies are a major cause of late death in heart-transplant patients.
The most common malignancies are tumours of the skin and lips (patients at highest risk are older, male and fair-skinned) and malignancies in the lymph system such as non-Hodgkin's lymphoma.
High blood pressure develops in more than 70% of heart transplant patients in the first year after transplant and in nearly 95% of patients in 5 years.
High levels of cholesterol and triglycerides in the blood develop in more than 50% of heart-transplant patients in the first year after transplant and in 84% of patients in 5 years.
Osteoporosis can develop or worsen in heart-transplant patients. This is a condition in which bones gradually become thinner and weaker.
Complications from not following lifelong healthcare plans
Not following a lifelong treatment plan increases the risk of all heart-transplant complications. Heart-transplant recipients are asked to closely follow their doctors' instructions and monitor their own health status throughout their lives.
Lifelong health care includes taking multiple medicines on a strict schedule, watching for signs and symptoms of complications, keeping all medical appointments, and stopping unhealthy behaviours such as smoking.
Source: US National Institutes of Health: Heart, Lung and Blood Institute