• coronary artery disease
• cardiomyopathy (noninflammatory disease of the heart)
• heart valve disease with congestive heart failure
• severe congenital heart disease
• life-threatening abnormal heart rhythms that do not respond to other therapy

• kidney, lung, or liver disease
• insulin-dependent diabetes with other organ dysfunction
• other types of vascular disease of the neck and leg arteries
• other life-threatening diseases

• reactions to medications
• problems breathing

• bleeding
• infection

Heart transplant prolongs the life of a patient who otherwise would die. About 80% of heart transplants are alive two years after the operation. The main problem, as with other transplants, is graft rejection. If rejection can be controlled, then survival can be increased to over 10 years for a person who otherwise would have died.

Immunosuppressive drugs must be taken indefinitely. Relatively normal activities can resume as soon as the patient feels well enough and after consulting with his or her doctor. However, vigorous physical activities should be avoided.

The major problems are the same for all major organ transplants:

• finding a donor
• fighting the rejection effect
• the cost of the surgery
• avoiding infection
• avoiding graft vasculopathy (blocked blood vessels in the transplanted organ)

Finding a donor can be difficult. In heart transplantation, the healthy heart must come from a fresh cadaver. This is different than a kidney transplant where a kidney can be donated by a family member. Also, timing is important because there is no good way to keep the transplanted heart alive for long periods of time before it is given to the recipient.

Recipients may be kept alive on artificial heart devices for increasingly longer periods of time. However, these can also have significant risks. While some of these devices are fully approved, others are still considered experimental.

Fighting rejection is an ongoing process. The body's immune system considers the transplanted organ an infection and automatically fights it. Thus, to prevent rejection, organ transplant patients must take drugs (such as cyclosporine and corticosteroids) that suppress the body's immune response. The disadvantage of these drugs is that they weaken the body's natural defense against various infections.