ablation - elimination or removal. Ablation also refers to a procedure that eliminates extra electrical pathways within the heart that cause fast or irregular heart rhythms.
ACE (angiotensin-converting enzyme) inhibitor - A medication that opens up blood vessels, making it easier for the heart to pump blood forward to the body; also used to lower blood pressure.
acute - severe; sharp; begins quickly.
acute lymphocytic leukemia (ALL) - a rapidly progressing cancer of the blood in which too many immature (not fully formed) lymphocytes, a type of white blood cell, are found in the bone marrow, blood, spleen, liver, and other organs.
acute myelogenous leukemia (AML) - a rapidly progressing cancer of the blood in which too many immature (not fully formed) granulocytes, a type of white blood cell, are found in the bone marrow and blood.
acyanotic - refers to a group of congenital heart defects in which there is a normal amount of oxygen in the bloodstream, giving a pink color to the lips and nail beds.
allogeneic bone marrow transplantation - a procedure in which a person receives stem cells from a compatible donor.
allograft - tissue or organ transplanted between genetically non-identical individuals of the same species (i.e., human to human).
alternative therapy - use of an unproven therapy instead of standard (proven) therapy.
alveolus - air sac where gas exchange takes place.
analgesic - any drug intended to alleviate pain.
anastomosis - a surgical connection, often between two blood vessels.
anemia - a blood disorder caused by a deficiency of red blood cells or hemoglobin (the oxygen-carrying protein in red blood cells).
anesthesia - the loss of feeling or sensation as a result of medications or gases. General anesthesia causes loss of consciousness. Local or regional anesthesia numbs only a certain area.
anesthesiologist - a physician who specializes in administering medications or other agents that prevent or relieve pain, especially during surgery.
aneurysm - a thin, weakened area in a blood vessel or area of the heart.
angiography - an x-ray study that uses dye injected into arteries to study blood circulation.
angioplasty - a non-surgical procedure for treating narrowed arteries.
antibiotic - a medication used to treat infection.
anticoagulant - a medication that keeps blood from clotting.
antiemetic - a medication that helps prevent and control nausea and vomiting.
antigen - a substance that can trigger an immune response, such as a transplant, causing the production of antibodies, a part of the body's defense mechanism.
antihypertensive - a medication that lowers blood pressure.
aorta - the largest artery in the body and the primary blood vessel which carries oxygenated blood out of the heart to the rest of the body.
aortic arch - the curved portion of the aorta (the large blood vessel that carries oxygen-rich blood away from the heart to the body).
aortic regurgitation - backwards leakage of blood from the aorta, through a weakened aortic valve, and into the left ventricle, resulting in stress in the left heart and inadequate blood flow to the body.
aortic stenosis - narrowing of the opening of the aortic valve (the valve that regulates blood flow from the left ventricle into the aorta).
aortic valve - the valve that regulates blood flow from the heart into the aorta.
apex - top portion of the upper lobes of the lungs.
apheresis - a procedure in which a patient's own blood is removed, particular fluid and cellular elements are extracted from the blood, then returned to the patient.
aplastic anemia - one type of anemia that occurs when the bone marrow produces too few of all three types of blood cells: red cells, white cells, and platelets.
arrhythmia (Also called dysrhythmia.) - a fast, slow, or irregular heartbeat.
arterioles - small branches of arteries.
arteriosclerosis - commonly called "hardening of the arteries;" a variety of conditions caused by fatty or calcium deposits in the artery walls causing them to thicken.
artery - a blood vessel that carries oxygenated blood away from the heart to the body.
ascites - fluid that fills the abdomen when the liver is not functioning properly.
asplenia - absence of the spleen, either from improper development before birth, or due to the surgical removal of the spleen resulting from injury or disease.
atresia - inadequate development of an organ or part of an organ during pregnancy.
atrial fibrillation - a very fast and irregular beating of the atria (the upper two chambers of the heart).
atrial flutter - a very fast beating of the atria (the upper two chambers of the heart).
atrial septal defect (ASD) - a hole in the wall between the right and left atria (the two upper chambers of the heart).
atrial septum - the wall between the right and left atria (the two upper chambers of the heart).
atrioventricular block - an interruption of the electrical signal between the atria and the ventricles.
atrioventricular canal - refers to a congenital heart defect involving an opening low in the atrial septum, an opening high in the ventricular septum, and abnormal development of the mitral and/or tricuspid valves.
atrioventricular node - a cluster of cells between the atria and ventricles that regulate the electrical current.
atrium (atria pl.) - one of two upper chambers in the heart.
autologous bone marrow transplantation - a procedure in which a patient's own bone marrow is removed, treated with anticancer drugs or radiation, then returned to the patient.
autosomal recessive inheritance - a gene on one of the first 22 pairs of chromosomes, which, when present in two copies, causes a trait or disease to be expressed.
bacterial endocarditis - a bacterial infection of the valves and interior surfaces of the heart.
balloon angioplasty - a procedure usually done in the cardiac catheterization laboratory that uses a catheter (tube) with a balloon in the tip to open up a narrowed valve or blood vessel.
barium - a liquid used to coat the inside of organs so they will show up on an x-ray.
base - bottom portion of the lower lobes of the lung, located just above the diaphragm.
benign - non-cancerous.
beta blocker - a medication that limits the activity of epinephrine (a hormone that increases blood pressure).
bicuspid - a valve that has two leaflets.
bilateral - affecting both sides.
bile - a digestive fluid made by the liver and stored in the gallbladder that helps digest fats.
bile ducts - tubes that take bile from the liver to the gallbladder and small intestine to aid in digestion.
biliary atresia - a condition in which bile ducts do not have normal openings, preventing bile from leaving the liver. This causes jaundice (yellowing of skin or eyes) and liver damage known as cirrhosis. Biliary atresia is a birth defect.
bilirubin - a normal substance produced when red blood cells break down and are excreted by the liver. Bilirubin gives bile its yellow-green color. Too much bilirubin in the blood causes jaundice.
biopsy - a procedure in which tissue samples are removed (with a needle or during surgery) from the body for examination under a microscope; to determine if cancer or other abnormal cells are present.
bladder - a triangle-shaped, hollow organ located in the lower abdomen that holds urine.
blasts - immature blood cells.
blood - the life-maintaining fluid which is made up of plasma, red blood cells (erythrocytes), white blood cells (leukocytes), and platelets; blood circulates through the body's heart, arteries, veins, and capillaries; it carries away waste matter and carbon dioxide and brings nourishment, electrolytes, hormones, vitamins, antibodies, heat, and oxygen to the tissues.
blood banking - the process that takes place in the laboratory to ensure that the donated blood or blood products are safe, before they are used in blood transfusions and other medical procedures. Blood banking includes typing and cross matching the blood for transfusion and testing for infectious diseases.
blood clot - a thick, gelled mass of blood.
blood plasma - the fluid part of blood that contains nutrients, glucose, proteins, minerals, enzymes, and other substances.
blood pressure - pressure of blood against the walls of a blood vessel or heart chamber.
blood pressure cuff - a device usually placed around the upper portion of the arm to measure blood pressure.
bone marrow - the soft, spongy tissue found inside bones. It is the medium for development and storage of about 95 percent of the body's blood cells.
bone marrow aspiration and biopsy - the marrow may be removed by aspiration or a needle biopsy under local anesthesia. In aspiration biopsy, a fluid specimen, is removed from the bone marrow. In a needle biopsy, marrow cells (not fluid) are removed. These methods are often used together.
bone marrow harvest - collection of stem cells with a needle placed into the soft center of the bone, the marrow.
bone marrow transplant (BMT) - the transfusion of healthy bone marrow cells into a person after their own unhealthy bone marrow has been eliminated.
bowel - small and large intestine.
bowel movement - passage of stool (body wastes) from the large intestine through the rectum and anus.
brady - suffix meaning slow.
bradycardia - abnormally slow heartbeat.
bronchiole - a small airway (subdivision of the bronchus) that leads to areas of the lung and absorbs oxygen from the air.
bronchiolitis - inflammation that involves the bronchioles (small airways).
bronchoscopy - a fiberoptic, flexible tube is passed through the mouth into the bronchi to locate tumors or blockages, and to gather samples of tissue and/or fluid.
bronchus - one of two large subdivisions of the trachea through which air passes to and from the lungs.
bundle-branch block - a condition in which the heart's electrical system is unable to normally conduct the electrical signal.
calcium channel blocker - a medication that lowers blood pressure.
cancer cell - a cell that divides and multiplies uncontrollably and has the potential to spread throughout the body, crowding out normal cells and tissue.
capillaries - tiny blood vessels between arteries and veins that distribute oxygen-rich blood to the body.
carbohydrates - one of three main types of foods, along with proteins and fats; found in breads, cereals, grains, fruits, and vegetables; changes into a simple sugar called glucose during digestion; provides the body with a source of energy.
carcinogen - an agent (chemical, physical, or viral) that causes cancer. Examples include tobacco smoke and asbestos.
cardiac - pertaining to the heart.
cardiac arrest - the stopping of the heartbeat.
cardiac catheterization - a diagnostic procedure in which a tiny, hollow tube (catheter) is inserted into an artery or vein in order to evaluate the heart and blood vessels.
cardiac output - total amount of blood being pumped by the heart over a particular period of time.
cardiologist - a physician who specializes in the medical evaluation and treatment of heart diseases.
cardiology - the clinical study and practice of treating the heart.
cardiomyopathy - a disease of the heart muscle that causes it to lose its pumping strength.
cardiovascular (CV) - pertaining to the heart and blood vessel (circulatory) system.
cardioversion - the procedure of applying electrical shock to the chest to change an abnormal heartbeat into a normal one.
carotid artery - the major arteries in the neck that supply blood to the brain.
catheter - a flexible tube used to drain fluid from or inject fluid into the body. The most common catheters are the Foley catheter, used to drain urine from the bladder, and intravenous (IV) catheters inserted into veins to administer fluids.
cecum - the beginning of the large intestine; attached to the last section of the small intestine, known as the ileum.
chemotherapy - a medication that can help fight cancer.
child life specialist - a hospital staff member who has special training in the growth and development of children. A Child Life Specialist can help your child with play activities, relaxation and pain management skills and help meet the educational and emotional needs of the entire family.
cholangiography - x-rays of the bile ducts.
cholesterol - a substance normally made by the body, but also found in foods from animal sources, like beef, eggs, and butter. Too much cholesterol in the body can lead to narrowing and blockage of the arteries, especially those that feed the heart and keep it healthy. High cholesterol can also cause the formation of gallstones. Ideally, blood cholesterol levels should be less than 200mg/dL.
chromosome - structures in our cells that carry genes, the basic units of heredity. Humans have 23 pairs of chromosomes, one member of each pair inherited from the mother, the other from the father. Each chromosome can contain hundreds or thousands of individual genes.
chronic - referring to a disease or disorder that usually develops slowly and lasts for a long period of time.
chronic myelogenous leukemia (CML) - a slowly progressing cancer of the blood in which too many white blood cells are produced in the bone marrow.
cineangiography - the procedure of taking moving pictures to show the passage of dye through blood vessels.
circulatory system - pertaining to the heart and blood vessels and the circulation of blood.
cirrhosis - a chronic problem that makes it hard for the liver to remove toxins (poisonous substances) from the body. Alcohol, medications, and other substances may build up in the bloodstream and cause problems. Cirrhosis is a result of scarring and damage from other diseases, such as biliary atresia and alcoholism.
closed heart surgery - an operation that repairs problems involving the blood vessels attached to the heart and may not need the use of the heart-lung bypass machine.
clotting - the sealing of a blood vessel with coagulated blood.
coarctation of the aorta - a congenital heart defect that results in narrowing of the aorta.
collateral vessels - new blood vessels that are created by the body to provide extra blood flow to an area when the blood vessel(s) that are already there are too small, narrowed, or blocked.
colon - the large intestine.
colonoscopy - a test using a long, flexible tube with a light and camera lens at the end, which examines the large intestine.
common bile duct - a tube that moves bile from the liver to the small intestine.
complete blood count (CBC) - a measurement of size, number, and maturity of different blood cells in a specific volume of blood.
compliance - fulfillment by the patient of the prescribed orders of treatment (i.e., taking medications after a transplant).
computed tomography scan (Also called a CT or CAT scan.) - a diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general x-rays.
conduction system - the electrical system inside the heart that stimulates the heart to beat.
congenital - present at birth.
congenital heart defect - a heart problem present at birth, caused by improper development of the heart during fetal development.
congenital heart disease - see congenital heart defect.
congestive heart failure - a condition in which the heart cannot pump out all of the blood that enters it, which leads to an accumulation of blood in the vessels leading to the heart and fluid in the body tissues. Excess blood in the pulmonary (lung) blood vessels can also occur, leading to fluid accumulation in the lungs.
constrict - tighten; narrow.
coronary arteries - two arteries that come from the aorta to provide blood to the heart muscle.
corticosteroids - medications that reduce irritation and inflammation.
culture - a laboratory test that involves the growing of bacteria or other microorganisms to aid in the diagnosis.
cyanosis - bluish color in the skin because of insufficient oxygen.
cyanotic - appearing blue, due to insufficient oxygen in the blood.
cystoscopy (Also called cystourethroscopy.) - an examination in which a scope, a flexible tube and viewing device, is inserted through the urethra to examine the bladder and urinary tract for structural abnormalities or obstructions, such as tumors or stones.
cystourethrogram (Also called a voiding cystogram.) - a specific x-ray that examines the urinary tract. A catheter (hollow tube) is placed in the urethra (tube that drains urine from the bladder to the outside of the body) and the bladder is filled with a liquid dye. X-ray images will be taken as the bladder fills and empties. The images will show if there is any reverse flow of urine into the ureters and kidneys.
defibrillator - an electronic device used to establish normal heartbeat.
dehydration - when the bloodstream and the cells of the body contain less fluid than normal, often due to vomiting or diarrhea. The body's mineral balance may also be affected.
descending colon - the portion of the large intestine located on the left side of the body.
dextrocardia - a heart that is "flipped over," so that the structures that are normally on the right side of the chest are on the left, and vice versa. The arteries and veins are connected correctly; occurs due to an abnormality in heart development during pregnancy.
dialysis - a medical procedure to remove wastes and additional fluid from the blood after the kidneys have stopped functioning.
diaphragm - primary muscle used for respiration, located just below the lung bases.
diastole - the time during each heartbeat when the ventricles are at rest, filling with blood and not pumping.
diastolic blood pressure - the lowest blood pressure measure in the arteries, which occurs between heartbeats.
DiGeorge syndrome (Also known as Shprintzen, velo-cardio-facial, and 22q11.2 deletion syndrome.) - A genetic disease caused by a missing piece of chromosome material on chromosome #22 that results in many different health problems, and affects the normal fetal development of the heart, thymus, and parathyroid glands.
digestion - how the body breaks down food and uses it for energy, cell repair, and growth. Digestion starts in the mouth, continues in the stomach and small intestine, and is completed in the large intestine. The liver and pancreas add enzymes and juices that aid in this process.
digestive tract - the organs that are involved in digestion, including the mouth, salivary glands, esophagus, stomach, pancreas, liver, gallbladder, small intestine, and large intestine.
dilate - relax; expand.
distention - swelling or bloating, usually referring to the abdomen.
diuretic - a medication that helps the kidneys to remove excess fluids from the body, lowering blood pressure as well as decreasing edema (swelling).
Doppler ultrasound - A procedure that uses sound waves to evaluate heart, blood vessels, and valves.
double outlet right ventricle - a congenital heart defect in which both the aorta and the pulmonary artery are connected to the right ventricle.
Down syndrome (Also called trisomy 21.) - A combination of birth defects caused by the presence of an extra #21 chromosome in each cell of the body. Many children with Down syndrome also have congenital heart disease - usually atrioventricular canal defect.
ductus arteriosus - a connection between the aorta and the pulmonary artery that is necessary in fetal life, but becomes unnecessary after birth.
dyspnea - shortness of breath or a difficulty in breathing.
dysrhythmia (Also called arrhythmia.) - a fast, slow, or irregular heartbeat.
Ebstein's anomaly - Abnormal development of the tricuspid valve during pregnancy, causing an abnormally positioned valve that does not open easily (stenosis) and allows backflow of blood from the right ventricle into the right atrium (regurgitation).
echocardiogram (echo) - a procedure that evaluates the structure and function of the heart by using sound waves recorded on an electronic sensor which produce a moving picture of the heart and heart valves.
edema - swelling due to the buildup of fluid.
effusion - a collection of fluid in a closed cavity.
ejection fraction - the measurement of the amount of blood pumped out of the ventricles.
electrocardiogram (ECG or EKG) - a test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias or dysrhythmias), and detects heart muscle damage.
electroencephalogram (EEG) - a procedure that records the brain's continuous electrical activity by means of electrodes attached to the scalp.
electrolytes - minerals in the bloodstream and in the cells of the body, such as sodium (salt), potassium, and calcium. Electrolytes must remain in proper balance for the body to function normally.
electrophysiological study (EPS) - a cardiac catheterization to study electrical current in patients who have arrhythmias.
endocarditis - a bacterial infection of the valves and interior surfaces of the heart.
endocardium - the membrane that covers the inside surface of the heart.
endoscope - a small, flexible tube with a light and a camera lens at the end used to examine the inside of the digestive tract. It can also be used to take tissue samples for testing from inside the digestive tract.
endoscopy - a test that uses an endoscope to examine the inside of part of the digestive tract.
end-stage organ disease - a disease that leads to functional failure of an organ, such as cardiomyopathy (heart).
end-to-end anastomosis - surgical connection of two segments of blood vessel by stitching the open end of one segment to the open end of another segment.
enema - a liquid placed into the rectum to either clear stool out of the large intestine or to examine the large intestine with an x-ray (barium enema).
enlarged heart - a condition of the heart in which it is larger than normal.
enuresis - involuntary discharge of urine usually during sleep at night; bedwetting beyond the age when bladder control should have been established.
eosinophils - a type of white blood cell that can increase in allergy and other infections.
epicardium - the membrane that covers the outside of the heart.
esophagus - the tube that connects the mouth to the stomach.
excrete - remove waste from the body.
exercise electrocardiogram (ECG or EKG) - a test that assesses cardiac rhythm and function during exercise on a treadmill or bicycle.
expiration - exhaling; giving off carbon dioxide.
factor - a protein in the blood that is needed to form a blood clot.
fats - one of three main types of foods, along with proteins and carbohydrates; provides the body with a source of energy; needs bile in order to be digested properly and utilized for energy.
fibrillation - rapid contractions of the heart muscles.
fluoroscopy - an x-ray procedure that takes continuous pictures to evaluate moving structures within the body, such as the heart.
flutter - ineffective contractions of the heart muscles.
Fontan procedure - A surgical procedure performed to repair heart defects in which only one ventricle is functional. It connects the right atrium to the pulmonary artery, allowing oxygen-poor (blue) blood from the body to flow into the lungs.
foramen ovale - a hole between the right and left atria, present in all unborn children, that remains open after birth for variable periods of time.
gallbladder - stores bile made by the liver; sends bile into the small intestine to help digest fats.
gas - air that collects in the stomach and intestines as a natural result of digesting food; passed out of the body via the rectum or the mouth.
gastric - related to the stomach.
gastrointestinal - relating to the digestive tract.
gastrointestinal tract (Also called the digestive tract.) - the parts of the body that break down food into small particles, allowing nutrients from food to be used for energy and growth: the mouth, esophagus, stomach, pancreas, liver, gallbladder, small intestine, and large intestine.
gene - a segment of DNA that codes for a trait such as blood type or eye color, as well as susceptibility to certain diseases.
gene therapy - inserting a normal gene into a person to replace a non-working or missing gene.
genetic - determined by genes or chromosomes.
Glenn shunt - a surgical connection between the superior vena cava and the right pulmonary artery, allowing oxygen-poor (blue) blood to flow into the lungs.
glomerulonephritis - a type of glomerular kidney disease in which the kidneys' filters become inflamed, scarred and slowly lose their ability to remove wastes and excess fluid from the blood to make urine.
glomerulosclerosis - the term used to describe scarring that occurs within the kidneys in the small balls of tiny blood vessels called the glomeruli. The glomeruli assist the kidneys in filtering urine from the blood.
glucose - a simple sugar made by the body from carbohydrates in food. Glucose is the body's main source of energy.
graft - transplanted organs, tissues, or cells.
graft-versus-host disease (GVHD) - the condition that results when the immune cells of a transplant (usually of bone marrow) react against the tissues of the person receiving the transplant.
granulocytes - a type of white blood cells. The different types of granulocytes include basophils, eosinophils, and neutrophils.
heart attack (Also called myocardial infarction.) - occurs when one or more regions of the heart muscle experience a severe or prolonged decrease in oxygen supply caused by a blocked blood flow to the heart muscle.
heart block - interrupted electrical impulse to heart muscles.
heartbeat - one complete contraction of the heart.
heart-lung bypass machine - a machine that performs for the heart and lungs during open heart surgery.
heart valve prolapse - a condition of the heart valve in which it is partially open when it should be closed.
hematocrit - the measurement of the percentage of red blood cells found in a specific volume of blood.
hematologist - a physician who specializes in the functions and disorders of the blood.
hematology - the scientific study of blood and blood-forming tissues.
hematopoiesis - the process of producing and developing new blood cells.
hematuria - the presence of red blood cells in the urine.
hemoglobin - a type of protein in the red blood cells that carries oxygen to the tissues of the body.
hemoglobin S-beta thalassemia - having one copy of the gene that causes sickle cell anemia (HbS) and one copy of a mutated gene in the beta-chain of hemoglobin; this blood disorder produces a moderate anemia and some symptoms similar to sickle cell anemia.
hemolytic anemia - one type of anemia in which the red blood cells are destroyed prematurely.
hemolytic uremic syndrome - a rare kidney disorder that mostly affects children under the age of 10. It is often characterized by damage to the lining of blood vessel walls, destruction of red blood cells, and/or kidney failure.
hemophilia (Also called a coagulation disorder.) - an inherited bleeding disorder caused by low levels, or absence of, a blood protein that is essential for clotting; hemophilia A is caused by a lack of the blood clotting protein factor VIII; hemophilia B is caused by a deficiency of factor IX.
hemorrhagic anemia - anemia caused by a sudden loss of a large amount of blood.
hepatic - relating to the liver.
hepatitis - inflammation of the liver that sometimes causes permanent damage; caused by viruses, drugs, alcohol, or parasites. Hepatitis has the following forms:
hepatitis A - a form of infectious hepatitis caused by the hepatitis A virus. The virus may be spread by fecal-oral contact, fecal-infected food or water, and may also be spread by a blood-borne infection (which is rare).
hepatitis B - a form of infectious hepatitis caused by the hepatitis B virus. Transmission of the hepatitis B virus occurs through blood and body fluid exposure, such as blood, semen, vaginal secretions, or saliva.
hepatitis C - a form of infectious hepatitis caused by the hepatitis C virus. Transmission of the hepatitis C virus occurs primarily from contact with infected blood, but can also occur from sexual contact or from an infected mother to her baby.
hepatitis D - a form of infectious hepatitis caused by the hepatitis (Delta) virus. This form of hepatitis can only occur in the presence of hepatitis B. Transmission of hepatitis D occurs the same way as hepatitis B.
hepatitis E - a form of infectious hepatitis caused by the hepatitis E virus. This form of hepatitis is similar to hepatitis A. Transmission occurs through fecal-oral contamination. Hepatitis E is most common in poorly developed countries and is rarely seen in the US.
hepatitis G - the newest form of infectious hepatitis. Transmission is believed to occur through blood and is seen in IV drug users, individuals with clotting disorders, such as hemophilia, and individuals who require hemodialysis for renal failure.
hepatoblastoma - cancer that originates in the liver.
high density lipoprotein (HDL) - the "good" cholesterol that promotes breakdown and removal of cholesterol from the body.
Holter monitor - A portable EKG machine worn for a 24-hour period or longer to evaluate irregular, fast, or slow heart rhythms while engaging in normal activities.
homograft - a blood vessel taken from a tissue donor, used to replace a defective blood vessel, most often the pulmonary artery or aorta.
hyperbilirubinemia - too much bilirubin in the bloodstream, due to liver problems; causes a yellow color of the skin known as jaundice.
hypertrophic obstructive cardiomyopathy (Also called HOCM, hypertrophic cardiomyopathy, asymmetrical septal hypertrophy, or ASH, or idiopathic hypertrophic subaortic stenosis, or IHSS.) - enlarged heart muscle that causes impeded blood flow.
hypoplastic - refers to an abnormally small organ or blood vessel due to abnormal development prior to birth.
hypoplastic left heart syndrome - a congenital heart defect in which the left side of the heart is poorly developed, resulting in a small mitral valve, left ventricle, and aorta.
hypotension - low blood pressure.
hypoxia - abnormal oxygen content in the organs and tissues of the body.
IgE antibody - One of the antibodies made by the body found mostly in the skin, nose, lining of the airways, and lungs; involved in allergic reactions.
ileum - the lower end of the small intestine.
imaging studies - methods used to produce a picture of internal body structures. Some imaging methods include x-rays, CT scans, magnetic resonance imaging (MRI), and ultrasound.
immune system - the system composed of lymph fluid, lymph nodes, the lymphatic system, and white blood cells that are responsible for protecting the body against infection and disease.
immunosuppression - a state in which the ability of the body's immune system to respond is decreased. This condition may be present at birth, or it may be caused by certain infections (such as human immunodeficiency virus, or HIV), or by certain cancer therapies, such as cancer cell killing (cytotoxic) drugs, radiation, and bone marrow transplantation.
immunosuppressive medications - medications that suppress the body's immune system; used to minimize rejection of transplanted organs.
immunotherapy - treatments that promote or support the body's immune system response to a disease such as cancer.
incision - a cut made with a surgical instrument during an operation.
indigestion - feeling of nausea, bloating, gas, and/or heartburn caused by poor digestion.
infection - the invasion of the body by microorganisms that cause disease.
inferior vena cava - the large blood vessel (vein) that returns blood from the legs and abdomen to the heart.
informed consent - a legal document that explains a course of treatment, the risks, benefits, and possible alternatives; the process by which patients agree to treatment.
inspiration - inhaling; taking in oxygen.
insufficiency - a valve deformity that allows the blood to leak backwards when the valve is closed.
insulin - a hormone that regulates sugar in the body.
intestine - digestive organs found in the abdomen, also known as either the large or small bowel. The small intestine removes nutrients from food to be used for energy, while the large intestine absorbs water from the digested food and processes it into stool.
intravenous gamma globulin (IVGG) - a protein that contains many antibodies and slows destruction of platelets.
intravenous (IV) line - a thin, plastic tube inserted into a vein (usually in the patient's forearm) through which a volume of fluid is injected into the bloodstream.
intravenous pyelogram (IVP) - a series of x-rays of the kidney, ureters, and bladder with the injection of a contrast dye into the vein - to detect tumors, abnormalities, kidney stones, or any obstructions, and to assess renal blood flow.
iron deficiency anemia - the most common type of anemia. It is the lack of iron in the blood, which is necessary to make hemoglobin.
ischemia - decreased flow of oxygenated blood to an organ due to obstruction in an artery.
ischemic heart disease - coronary artery disease or coronary heart disease caused by narrowing of the coronary arteries and decreased blood flow to the heart.
islet cells - cells within the pancreas that secrete insulin and other hormones involved in breaking down sugars.
jaundice - a yellow color of the skin and eyes that is caused by too much bilirubin in the bloodstream.
jejunum - the middle section of the small intestine.
jugular veins - veins that carry blood from the head back to the heart.
Kawasaki disease - An immune system disorder affecting the heart, particularly the coronary arteries.
kidney transplantation - a procedure that places a healthy kidney from one person into a recipient's body.
kidneys - a pair of bean-shaped organs located below the ribs toward the middle of the back.
laparoscope - a tube with a light and a camera lens at the end to examine organs and check for abnormalities.
laparoscopy - a procedure that uses a tube with a light and a camera lens at the end (laparoscope) to examine organs, check for abnormalities, or perform minimally invasive surgeries. Laparoscopy is a surgery which avoids making large incisions. Tissue samples may also be taken for examination and testing.
large intestine (Also called the colon.) - The last section of the digestive tract, from the cecum to the rectum; absorbs water from digested food and processes it into stool.
larynx (Also called voice box.) - a cylindrical grouping of cartilage, muscles, and soft tissue which contains the vocal cords. The vocal cords are the upper opening into the windpipe (trachea), the passageway to the lungs.
left atrium - the upper left-hand chamber of the heart. The left atrium receives oxygen-rich (red) blood from the lungs via the four pulmonary veins, and then sends this blood to the left ventricle.
left ventricle - the lower left-hand chamber of the heart. The left ventricle receives oxygen-rich (red) blood from the left atrium and pumps it into the aorta, which takes the blood to the body. The left ventricle must be strong and muscular in order to pump enough blood to the body to meet its requirements.
leukemia - a cancer of the blood-forming tissue. Leukemic cells look different than normal cells and do not function properly.
lipid - a fatty substance in the blood.
lipoproteins - transporters of fatty substances in the blood.
liver - a digestive organ located on the right side of the abdomen, under the ribs; has many important functions, including storing and helping make blood, making bile (which aids in the digestion of fats in the food we eat), processing medicines and removing toxins from the bloodstream, and changing food and fats stored in our bodies into energy.
liver function tests - blood tests that indicate how well the liver is working.
lobectomy - removal of an entire lobe of the lung.
low density lipoprotein (LDL) - the primary cholesterol-carrying substance in the body. In large amounts, it accumulates inside arteries.
lower GI series - a study that looks at the rectum, the large intestine, and the lower part of the small intestine. A fluid called barium that shows up well on x-rays is given into the rectum as an enema. X-rays of the abdomen shows strictures (narrowed areas), obstructions (blockages), and other problems.
lumen - the hollow area inside a blood vessel.
lung volume - the amount of air the lungs hold.
lymph - part of the lymphatic system; a thin, clear fluid that circulates through the lymphatic vessels and carries blood cells that fight infection and disease.
lymph nodes - part of the lymphatic system; bean-shaped organs found in the underarm, groin, neck, and abdomen; they act as filters for the lymph fluid as it passes through them.
lymph vessels - part of the lymphatic system; thin tubes that carry lymph fluid throughout the body.
lymphatic system - part of the immune system; includes lymph, ducts, organs, lymph vessels, lymphocytes, and lymph nodes, whose function is to produce and carry white blood cells to fight disease and infection.
lymphocytes - part of the lymphatic system; white blood cells that fight infection and disease.
lymphocytic leukemia - a type of leukemia in which the cancer develops in the lymphocytes (lymphoid cells).
magnetic resonance imaging (MRI) - a diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body.
malignant - a term used to describe cancerous tumors which tend to grow rapidly, can invade and destroy nearby normal tissues, and can spread.
Marfan syndrome - A genetic disorder that affects the connective tissue of the body. It causes dilation of blood vessels and abnormalities of cardiac valves.
mechanical valve - an artificial valve used to replace a diseased or defective valve, most often the aortic valve.
median sternotomy - an incision in the center of the chest, from the top to the bottom of the breastbone, used for many congenital heart defect repair surgeries.
megaloblastic (pernicious) anemia - a rare blood disorder in which the body does not absorb enough vitamin B-12 from the digestive tract, resulting in an inadequate amount of red blood cells (RBCs) produced.
metastasis - the spread of tumor cell in other areas of the body.
mitral valve - the valve that controls blood flow between the left atrium and left ventricle in the heart.
mitral valve prolapse - an abnormality of the valve between the left atrium and left ventricle of the heart that causes backward flow of blood from the left ventricle into the left atrium.
monounsaturated fats - dietary fats, such as olive oil or canola oil, that may lower LDL cholesterol levels.
mucositis - inflammation of the mouth and gastrointestinal tract.
murmur - a blowing or rasping sound heard while listening to the heart that may or may not indicate problems within the heart or circulatory system.
mutation - a change in a gene.
myelogenous leukemia - a type of leukemia in which the cancer develops in the granulocytes or monocytes (myeloid cells).
myelogram - an x-ray of the spine, similar to an angiogram.
myeloproliferative disorders - diseases in which the bone marrow produces too many of one of the three types of blood cells: red blood cells, which carry oxygen to all the tissues in the body; white blood cells, which fight infection; and platelets, which cause blood to clot.
myocardial infarction (Also called heart attack.) - occurs when one of more regions of the heart muscle experience a severe or prolonged decrease in oxygen supply caused by blocked blood flow to the heart muscle.
myocardial ischemia - insufficient blood flow to part of the heart.
myocarditis - inflammation of the heart muscles.
myocardium - the muscular layer of the heart.
nephrectomy - surgery to remove the kidney; the most common treatment for kidney cancer.
nephrologist - a physician who specializes in diseases of the kidneys.
nephrology - the medical specialty concerned with diseases of the kidneys.
nephrotic syndrome - a condition characterized by high levels of protein in the urine, low levels of protein in the blood, tissue swelling, and high cholesterol.
neuroblastoma - cancer occurring in the nerve cells.
neurosurgeon - a physician specializing in operations to treat disorders of the nervous system.
noninvasive procedure - a diagnostic effort or treatment that does not require entering the body or puncturing the skin.
occluded artery - an artery that is narrowed by plaque that impedes blood flow.
oncologist - a physician who specializes in the diagnosis and treatment of cancer.
oncology - the branch of medicine concerned with the diagnosis and treatment of cancer.
open heart surgery - surgery that involves opening the chest and heart while a heart-lung machine performs for the heart and lungs during the operation.
oxygen desaturation - insufficient amounts of oxygen in the bloodstream. Desaturation can occur when oxygen-poor (blue) blood from the right side of the heart circulation mixes with oxygen-rich (red) blood in the left side of the heart circulation and goes to the body. Normal oxygen saturation in the arteries is 95 to 100 percent.
oxygen saturation - the extent to which the hemoglobin is saturated with oxygen. (Hemoglobin is an element in the bloodstream that binds with oxygen and carries it to the organs and tissues of the body.) A normal oxygen saturation of the blood leaving the heart to the body is 95 to 100 percent. The oxygen saturation of the blood returning to the heart after delivering oxygen to the body is 75 percent.
pacemaker - an electronic device that is surgically placed in the patient's body and connected to the heart to regulate the heartbeat.
pain specialist - oncologists, neurologists, anesthesiologists, neurosurgeons, and other physicians, nurses, or pharmacists who are experts in pain. A team of healthcare professionals may also be available to address issues of pain control.
palpitation - sensation of rapid heartbeats.
pancreas - an organ located underneath the stomach that produces enzymes that aid in digestion, and also produces hormones such as insulin, which helps the body use sugar for energy.
parenteral nutrition - a means of providing protein, fats, carbohydrates, fluid, and vitamins to the body through a special solution given through a vein into the bloodstream.
patent - open.
patent ductus arteriosus (PDA) - a blood vessel present in all infants that usually closes shortly after birth. It connects the aorta to the pulmonary artery. When it remains open, it allows extra blood to pass through from the aorta to the lungs.
patent foramen ovale - an opening in the atrial septum (wall between the right and left atria) that is present in all infants, but which usually closes shortly after birth. When it remains open, it allows extra blood to pass through the opening from the left atrium to the right atrium.
pathologist - a physician who specializes in diagnosis and classification of diseases by laboratory tests such as examination of tissue and cells under a microscope. The pathologist determines whether a tumor is benign or cancerous and, if cancerous, the exact cell type and grade.
pediatric gastroenterologist - a physician who treats infants and children with diseases of the digestive system.
pediatric oncologist - a physician who specializes in cancers of children.
pediatrician - a physician who specializes in the care of children.
percutaneous - through the skin.
perforation - a hole in the wall of an organ.
perfusion - flow.
pericardial effusion - a build-up of excess fluid in-between the heart and the membrane that surrounds it, often due to inflammation.
pericardiocentesis - a diagnostic procedure that uses a needle to draw fluid from the pericardium.
pericarditis - an inflammation or infection of the sac which surrounds the heart.
pericardium - the membrane that surrounds the heart.
peripheral blood stem cell collection - stem cells are collected from the circulating cells in the blood.
peritonitis - an infection inside the abdominal cavity.
petechia - tiny red dots under the skin that are the result of very small bleeds.
pharynx - the throat.
physical therapist - a health professional who uses exercises and other methods to restore or maintain the body's strength, mobility, and function.
plaque - deposits of fat or other substances attached to the artery wall.
plasma - the watery, liquid part of the blood in which the red blood cells, the white blood cells, and platelets are suspended.
platelets - cells found in the blood that are needed to help the blood to clot in order to control bleeding; often used in the treatment of leukemia and other forms of cancer.
pleura - membrane that covers the outside of the lung.
pluripotent stem cell - the most primitive, undeveloped blood cell.
pneumonectomy - removal of an entire lung.
polycystic kidney disease (PKD) - a genetic disorder characterized by the growth of numerous cysts filled with fluid in the kidneys.
polyunsaturated fat - a type of fat found in vegetable oils and margarines that does not appear to raise blood cholesterol levels.
portal hypertension - high blood pressure in the portal vein that carries blood to the liver.
portal vein - the large vein that carries blood to the liver from the spleen and intestines.
post-anesthesia care unit (Also called recovery room.) - the area a patient is brought to after surgery to recover.
post-pericardiotomy syndrome - a build-up of excess fluid in-between the heart and the membrane that surrounds it, often due to inflammation after open heart surgery. ("Post" means after, and "pericardiotomy" means opening the membrane around the heart for open heart surgery.)
premature atrial contraction (PAC) - an early heartbeat started by the atria.
premature ventricular contraction (PVC) - an early heartbeat started by the ventricles.
prognosis - a prediction of the course of disease; the outlook for the cure of the patient.
prophylaxis - prevention.
prostaglandin E1 - an intravenous medication used to keep a patent ductus arteriosus from closing and preserve blood flow to the lungs.
proteinuria - large amounts of protein in the urine.
protocol - a formal outline or plan, such as a description of what treatments a patient will receive and exactly when each should be given.
pulmonary - pertaining to the lungs and respiratory system.
pulmonary artery - blood vessel delivering oxygen-poor blood from the right ventricle to the lungs.
pulmonary edema - a condition in which there is fluid accumulation in the lungs caused by an incorrectly functioning heart.
pulmonary hypertension - abnormally high blood pressure in the arteries of the lungs.
pulmonary valve - the heart valve located between the right ventricle and the pulmonary artery that controls blood flow to the lungs.
pulmonary vein - the vessel that carries oxygenated blood from the lungs to the left side of the heart.
pulse oximeter - a device that measures the amount of oxygen in the blood. Normal oxygen saturation in the arteries is 95 to 100 percent.
pulse oximetry - a device used to measure the amount of oxygen in the blood.
purpura - the purple color of skin after blood has "leaked" under it, such as in a bruise.
pylorus - where the stomach connects to the small intestine.
radiation therapist - a professional specially trained to operate equipment that delivers radiation therapy.
radioisotope - a radioactive material injected into the body so that a nuclear scanner can make pictures.
radiologist - a physician with special training in diagnosing diseases by interpreting x-rays and other types of imaging studies (i.e., CT scans and magnetic resonance imaging).
rectum - the lower end of the large intestine.
red blood cells (Also called RBCs or erythrocytes.) - blood cells that mainly help transport oxygen to all the tissues in the body.
regimen - a strict, regulated plan (such as diet, exercise, or other activity) designed to reach certain goals. In cancer treatment, a plan to treat cancer.
regurgitation - backward flow of blood caused by a defective heart valve.
rejection - an immune system response to transplanted tissues or organs.
renal - pertaining to the kidneys.
renal angiography (Also called renal arteriography.) - a series of x-rays of the renal blood vessels with the injection of a contrast dye into a catheter, which is placed into the blood vessels of the kidney to detect any signs of blockage or abnormalities affecting the blood supply to the kidneys.
renal ultrasound - a non-invasive test in which a transducer wand is passed over the kidney, produces sound waves which bounce off of the kidney, transmitting a picture of the organ on a video screen. The test is used to determine the size and shape of the kidney and to detect a mass, kidney stone, cyst, or other obstruction or abnormalities.
respiration - gas exchange from air to the blood and from the blood to the body cells.
rheumatic fever - a disease caused by a strep infection that may damage the heart valves.
right atrium - the upper right chamber of the heart, which receives oxygen-poor (blue) blood from the body and sends it to the right ventricle.
right ventricle - the lower right chamber of the heart, which receives oxygen-poor (blue) blood from the right atrium and sends it to the pulmonary artery.
risk factor - anything that increases a person's chance of developing a disease, such as cancer.
Ross procedure - A surgical procedure performed to repair aortic stenosis. The child's own pulmonary valve and base of the pulmonary artery (autograft) replace the defective aorta, while a homograft (blood vessel from a tissue donor) replaces the pulmonary valve and base of the pulmonary artery.
rubella - an illness that can cause birth defects, including congenital heart disease, if a woman contracts it for the first time during pregnancy; can be prevented by immunization with the MMR vaccine.
saline solution - a solution containing sodium chloride.
sarcoma - a malignant tumor growing from connective tissues, such as cartilage, fat, muscle, or bone.
saturated fat - fat that is found in foods from animal meats and skin, dairy products, and some vegetables. Saturated fats are usually solid at room temperatures and can increase LDL levels.
septal defect - a hole in the wall between the atria or the ventricles (upper or lower heart chambers).
septum - the muscle wall between the atria or ventricles (upper or lower heart chambers).
shunt - a connector to allow blood flow between two locations.
sickle cell anemia - an inherited blood disorder characterized by defective hemoglobin, where there are two copies of an abnormal hemoglobin gene present (HbSS).
sickle cell - hemoglobin C disease - having one copy of the gene which causes sickle cell anemia (HbS) and one copy of another altered hemoglobin gene (HBc); this blood disorder is similar to sickle cell anemia.
sickle cell - hemoglobin E disease - having one copy of the gene which causes sickle cell anemia (HbS) and one copy of another altered hemoglobin gene (HbE); this blood disorder may/may not cause symptoms except under stress (exhaustion, infection, etc.).
sickle cell trait - having one copy of the gene which causes sickle cell anemia (HbS), and one copy of the normal hemoglobin gene.
sickle crisis (Also called pain crisis or vasoocclusive crisis.) - in sickle cell diseases, the pain that occurs when the flow of blood is blocked to an area because the sickled cells are stuck in a blood vessel.
side effects - unwanted effects of treatment such as hair loss caused by chemotherapy and fatigue caused by radiation therapy.
sigmoid colon - the lower part of the large intestine that empties into the rectum.
sinus node - the cells that produce the electrical impulses that cause the heart to contract.
sinus rhythm - a normal heart rhythm in which each heartbeat originates in the sinus node and proceeds through the rest of the electrical conduction system normally.
sinus tachycardia - a heart rhythm that originates in the sinus node and proceeds through the rest of the electrical conduction system, but is faster than normal.
small intestine - the section of the digestive tract between the stomach and the large intestine. Most of digestion occurs here as nutrients are absorbed from food.
smooth muscle - muscle that performs automatic tasks, such as constricting blood vessels.
sphincter muscles - circular muscles that help keep urine from leaking by closing tightly like a rubber band around the opening of the bladder.
sphygmomanometer - an instrument used to measure blood pressure.
spinal tap (Also called a lumbar puncture.) - a special needle is placed into the lower back, into the spinal canal. This is the area around the spinal cord. The pressure in the spinal canal and brain can then be measured. A small amount of cerebral spinal fluid (CSF) can be removed and sent for testing to determine if there is an infection or other problems. CSF is the fluid that bathes your child's brain and spinal cord.
spirogram - record of the amounts of air being moved in and out of the lungs.
spleen - an organ found on the left side of the abdomen, next to the stomach. Makes white blood cells that help fight infection and filters and cleanses the blood.
stem cells - the blood cells that produce other blood cells. It is the stem cells that are needed in bone marrow transplantation.
stenosis - narrowing or constriction of a blood vessel or valve in the heart.
stent - a device implanted in a vessel used to help keep it open.
sternotomy - a surgical incision made in the breastbone.
sternum - the breastbone.
stethoscope - an instrument used to listen to the heart and other sounds in the body.
stress - mental or physical tension that results from physical, emotional, or chemical causes.
stridor - a high-pitched sound heard best on inspiration.
stroke - the sudden disruption of blood flow to the brain.
subclavian - a blood vessel that branches from the aorta and takes oxygen-rich (red) blood to the head and arms.
superior vena cava - the large vein that returns blood to the heart from the head and arms.
supraventricular tachycardia - a fast heart rate that originates in the aorta, but does not start in the sinus node.
syncope - light-headedness or fainting caused by insufficient blood supply to the brain.
syngeneic bone marrow transplantation - an allogeneic transplant from an identical twin.
systemic - relating to a process that affects the body generally.
systole - the time during the heartbeat when the ventricles are pumping blood either to the lungs or to the body.
systolic blood pressure - the highest blood pressure measured in the arteries.
tachycardia - rapid heartbeat.
tachypnea - rapid breathing.
tamponade - an emergency situation that occurs when blood or fluid fills the pericardial sac surrounding the heart, preventing the heart from beating effectively.
telemetry unit - a small box with wires attached to EKG patches on the chest; used to send information about the heartbeat via radio transmission to healthcare professionals for evaluation.
tetralogy of Fallot (TOF) - a group of congenital heart defects, including a ventricular septal defect, obstruction to blood flow out of the right ventricle to the lungs, and an aorta that is shifted to the right. Enlargement of the right ventricle occurs as the right ventricle copes with obstruction to blood flow.
thalassemia - an inherited blood disorder in which the chains of the hemoglobin (a type of protein in red blood cells that carries oxygen to the tissues) molecule are abnormal; alpha thalassemia is where a mutation occurs in the alpha chain, while beta thalassemia is where the mutation occurs in the beta chain; signs and symptoms of thalassemias vary from mild (little to no symptoms) to severe (life-threatening).
thoracotomy - an incision made on the right or left side of the chest between the ribs in order to access the heart or lungs during surgery.
total parenteral nutrition - see parenteral nutrition.
transesophageal echocardiography (TEE) - a diagnostic test that uses a long tube guided into the mouth, throat, and esophagus to evaluate the structures inside the heart with sound waves.
transplantation - to transfer organs, tissues, or cells from one person to another or from one area of the body to another in order to replace a diseased structure and to restore function.
transposition of the great arteries (Also called transposition of the great vessels.) - a congenital heart defect involving abnormal development of the great arteries (the aorta and the pulmonary artery) during the time the heart is forming prior to birth. The aorta ends up being connected to the right ventricle, and the pulmonary artery is connected to the left ventricle, which is the opposite of how they are normally connected.
tricuspid atresia - a congenital heart defect in which the tricuspid valve and right ventricle do not develop properly, preventing oxygen-poor (blue) blood from reaching the lungs via its normal pathway.
tricuspid valve - the heart valve that controls blood flow from the right atrium into the right ventricle.
triglyceride - a fat-like substance found in the blood.
trisomy 21 (Also called Down syndrome.) - the presence of three #21 chromosomes in each cell of the body, rather than the usual pair, which causes the features otherwise known as Down syndrome. Many children with Down syndrome also have congenital heart disease - usually atrioventricular canal defect.
truncus arteriosus - a congenital heart defect involving incomplete separation of the great arteries (the aorta and the pulmonary artery) during the time the heart is forming prior to birth.
ultrasound (Also called sonography.) - a diagnostic imaging technique which uses high-frequency sound waves and a computer to create images of blood vessels, tissues, and organs. Ultrasounds are used to view internal organs as they function, and to assess blood flow through various vessels.
umbilical cord blood transplant - a bone marrow transplant using stem cells from cord blood.
unilateral - affecting one side of the body. For example, unilateral kidney cancer occurs in one kidney only.
United Network for Organ Sharing (UNOS) - A nonprofit, charitable organization that maintains the nation's organ transplant waiting list under contract with the Health Resources and Services Administration of the US Department of Health and Human Services. UNOS also helps to develop organ transplantation policies.
upper GI series - a test that looks at the organs of the upper part of the digestive system: the esophagus, stomach, and duodenum (upper small intestine). A liquid that shows up well on x-rays called barium is swallowed. X-rays are then taken to evaluate the digestive organs.
urea - the nitrogen part of urine produced from the breakdown of protein.
ureteroscope - an optical device which is inserted into the urethra and passed up through the bladder to the ureter; to inspect the opening of the ureters.
ureters - two narrow tubes that carry urine from the kidneys to the bladder.
urethra - narrow channel through which urine passes from the bladder out of the body.
urethritis - infection limited to the urethra.
urinalysis - laboratory examination of urine for various cells and chemicals, such as red blood cells, white blood cells, infection, or excessive protein.
urinary incontinence - loss of bladder control.
urinary tract infection - an infection that occurs in the urinary tract; often caused by bacteria such as Escherichia coli. A urinary tract infection often causes frequent urination, pain, burning when urinating, and blood in the urine.
urogenital - refers to the urinary and reproductive systems.
urologist - a physician who specializes in treating problems of the urinary tract in males and females.
urology - the branch of medicine concerned with the urinary tract in both genders, and with the genital tract or reproductive system in the male.
valves - the "doors" between the chambers of the heart that allow blood to move forward and prevent it from moving backward. The heart valves are called tricuspid, pulmonic, mitral, and aortic.
valvuloplasty - surgical repair of a heart valve for relief of stenosis or incompetence.
vascular - pertaining to blood vessels.
vasodilator - a medication that dilates or widens the opening in a blood vessel.
vasopressor - a medication that raises blood pressure.
vasovagal syndrome - a sudden drop in blood pressure, with or without a decrease in heart rate, that is caused by a dysfunction of the nerves controlling the heart and blood vessels.
vein - a blood vessel that carries blood from the body back into the heart.
ventilation - movement of air (gases) in and out of the lungs.
ventricle - one of the two pumping chambers of the heart; right ventricle receives oxygen-poor blood from the right atrium and pumps it to the lungs through the pulmonary artery; left ventricle receives oxygen-rich blood from the left atrium and pumps it to the body through the aorta.
ventricular fibrillation - a condition in which the ventricles contract in rapid and unsynchronized rhythms and cannot pump blood into the body.
ventricular septal defect - an abnormal opening in the wall between the right and left ventricles.
ventricular tachycardia - a condition in which the ventricles beat very quickly.
vertigo - dizziness.
vesicoureteral reflux (VUR) - the abnormal flow of urine from the bladder back into the ureters; often as a result of a urinary tract infection or birth defect.
vomiting - the release of stomach contents through the mouth; also known as throwing-up.
von Willebrand disease - a form of hemophilia caused by an abnormality in the von Willebrand factor, which is necessary for platelets to be able to attach themselves to a vein or artery to form a clot to stop bleeding.
white blood cells (Also called leukocytes or WBCs.) - blood cells involved in the destruction of viruses, bacteria, and fungi that cause infection.
Wilms tumor - A cancerous tumor originating in the cells of the kidney.
Wolff-Parkinson-White syndrome - An extra electrical pathway that connects the atria and ventricles and causes rapid heartbeat.
x-ray - a diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film.