Heart transplantation usually involves only the heart but occasionally the transplantation of both a heart and the lungs is needed. This can happen because the heart and lungs work closely together, and a problem that damages the heart may also damage the lungs, or vice versa. The heart will come from a recently deceased donor.
What does the heart do?
The heart consists of two upper chambers (atria) which receive and collect blood, and two lower chambers (ventricles) which pump the blood around the rest of the body. The blood delivers oxygen and nutrients around the body and carries away waste products and carbon dioxide.
The heart is located in the middle of the ribcage. Blood carrying oxygen from the lungs (shown in red) enters the left atrium and is pumped from the left ventricle around the rest of the body. Blood returns carrying waste products and carbon dioxide (shown in blue) to the right atrium and is pumped out to the lungs from the right ventricle.