H

Heart: A muscular organ that pumps blood through the body. The heart can be donated and transplanted.

Heart Valves: Prevent the back flow or leakage of blood as it is being pumped through the chambers inside of the heart. Heart valves can be donated and transplanted.

Hemodialysis: A treatment for kidney failure in which the patient's blood is passed through a filtering membrane to remove excess fluid and wastes.

Hemorrhage: A rapid loss of a large amount of blood; excessive bleeding.

Hepatic: Having to do with, or referring to, the liver.

Hepatitis: An inflammation of the liver that can lead to liver failure.

High blood pressure (hypertension): High blood pressure occurs when the force of the blood pushing against the walls of the blood vessels is higher than normal because the blood vessels

have either become less able to stretch or have gotten smaller. High blood pressure causes the heart to pump harder to move blood through the body. High blood pressure can cause kidney

failure and heart disease if not treated.

Histocompatibility: The examination or testing of antigens to determine if a donor organ will "match" and be compatible with a potential recipient's system. This routine test is often called tissue-typing and helps identify the most suitable recipient for a donated organ.

Human Leukocyte Antigens (HLA): A genetically determined series of markers (molecules) located on human white blood cells (leukocytes) and on tissues that are inherited from both biological parents. HLA matching is important for compatibility between donor and recipient.