Heart Center Heart glossary

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Elimination or removal.

A test performed to discover genetic disorders and birth defects. The test involves inserting a needle through the abdominal wall of a pregnant woman and into the amniotic sac to retrieve a sample of amniotic fluid.

A widening in a blood vessel or area of the heart that may result in a rupture.

A procedure to widen narrowed arteries.

An abnormal structural feature not usually present in a healthy individual.

The blood vessel that delivers oxygen-rich blood from the left ventricle to the body.

Aortic stenosis
Narrowing of the opening of the aortic valve.

Aortic valve
The valve that regulates blood flow from the left ventricle into the aorta. Consisting of three flaps, or cusps, it prevents blood from flowing back into the ventricle.

An abnormal rhythm of the heart.

Hardening and thickening of the walls of the arteries.

A blood vessel that carries oxygenated blood away from the heart to the body.

The absence of a normal opening in the body.

The top two chambers of the heart. A single chamber is called an atrium.

Atrial fibrillation
Irregular beating of the atria.

Atrial septal defect (ASD)
A hole in the wall between the right and left atria.


Balloon angioplasty
A procedure that uses a catheter (tube) with a balloon in the tip to open up a narrowed valve or blood vessel.

Balloon valvuloplasty
A procedure in which a balloon-tipped catheter is passed into the heart and across a narrow valve, then inflated in order to expand the valve opening.

Birth defect
Any defect present at birth; sometimes referred to as congenital.

Collection of a small sample of tissue for closer examination.

Blood pressure
The pressure of the blood flowing in the arteries.


Calcium channel blocker
A medication that lowers blood pressure.

Blood vessels between arteries and veins that distribute oxygen-rich blood to the body.

Pertaining to the heart.

Cardiac arrest
When the heart stops beating, either temporarily or permanently.

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.

A doctor who specializes in treating heart diseases.

The study and treatment of heart disorders.

A disease of the heart muscle that causes it to lose its pumping strength.

Pertaining to the heart and circulatory (blood vessels) system.

Carotid arteries
The major arteries in the neck that supply blood to the brain.

Closed-heart surgery
Surgery done on the heart without the use of the heart-lung machine.

An attack of crying and apparent abdominal pain in early infancy.

Any trait or condition existing at birth.

Congenital heart defect
A heart problem present at birth, caused by improper development of the heart during fetal development.

Congestive heart failure
Inability of the heart to pump blood efficiently, which results in inadequate blood flow to other organs.

The use of intense cold to destroy the source of abnormal electrical signals, which can cause the heart to beat irregularly.

Bluish color in the skin due to insufficient oxygen.

Condition in which the heart is positioned in the right side of the chest rather than in its normal location on the left.

Tests or procedures that are intended to evaluate a problem, rather than treat it.

Diastolic blood pressure
The pressure of blood inside arteries when the heart is at rest. In a blood pressure reading, it's the bottom number.


Echocardiogram (echo)
A procedure that evaluates the structure and function of the heart.

An increased amount of fluid in the body tissue that results in swelling or puffiness, especially in the hands, feet and around the eyes.

Electrocardiogram (ECG or EKG)
A test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias) and detects heart muscle damage.

Epidural anesthesia
Numbing drugs injected into the fluid sac that surrounds the spinal nerves to prevent pain signals from traveling up the spinal cord to reach the brain.

Esophageal electrophysiology study
A diagnostic test for abnormal heart rhythms. A thin tube is placed down the esophagus to send and receive electrical signals from the heart.


Portion of DNA that determines a characteristic of an organism. Human beings have around 100,000 genes.

Genetic counseling 
An assessment of inherited risk factors and information to patients concerning the consequences of a disorder, the probability of developing or transmitting it, and ways in which it can be prevented, treated and managed.

Genetic testing
Tests performed to determine if a person has a genetic condition or disease or is likely to get the disease.


Heart attack
Interruption of the normal circulation of the heart due to the loss of blood supply. Also called myocardial infarction.

Heart murmur
A noise that occurs as blood flows through the heart, that can be heard by listening with a stethoscope. Some murmurs are heard in children with normal hearts; others may indicate a structural abnormality that may or may not be serious.

Heart valve 
One of the four structures in the heart that control the flow of blood to and from the heart.

Heart valve prolapse 
A condition of the heart valve in which it is partially open when it should be closed.

Heart-lung machine 
A machine that does the work both of the heart (pumps blood) and the lungs (oxygenates the blood) during open-heart surgery.

High blood pressure
Blood pressure that is above the normal range. Also called hypertension.

High levels of lipds (fats) in the bloodstream; high cholesterol.

Refers to an organ or part of the body that is enlarged or overgrown.

Refers to an abnormally small organ or blood vessel due to abnormal development prior to birth.

Hypoplastic left heart syndrome (HLHS)
A congenital heart defect in which the left side of the heart is poorly developed, resulting in small mitral valve, left ventricle and aorta.

Low blood pressure.


Idiopathic disease
A disease for which no identifiable cause can be determined.

Passed on to an individual through the parent's genetic code.

Interrupted aortic arch
Part of the aorta is missing. This can lead to severely reduced blood flow to the lower part of the body.

Intravenous (IV)
Into a vein.

Medications or procedures intended to treat an existing problem.


Jugular veins
Veins that carry blood from the head back to the heart.


Left atrium
The upper left-hand chamber of the heart. It receives oxygen-rich (red) blood from the lungs, and then sends this blood to the left ventricle.

Left ventricle
The lower left-hand chamber of the heart. It receives oxygen-rich (red) blood from the left atrium and pumps it into the aorta, which takes the blood to the body.

Lung scan
A diagnostic test to determine the percent of blood flow to each lung by intravenously administering a small amount of fluid.


Magnetic resonance imaging (MRI)
A diagnostic procedure that uses a combination of large magnets, radio frequencies and a computer to produce detailed images of organs and structures within the body.

Marfan syndrome
A genetic disorder that affects the connective tissue of the body. It causes dilation of blood vessels and abnormalities of cardiac valves.

Mitral valve
The valve between the left atrium and left ventricle. Consisting of two flaps, or cusps, it prevents blood from flowing back into the atrium from the ventricle.

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.

The muscular part of the heart which pumps blood. 

Open-heart surgery
Surgery done on an opened heart while blood flow is being diverted through a heart-lung machine.

Narcotic drugs such as morphine and fentanyl often are used to reduce the pain from surgery. While very effective at controlling pain, these drugs may have side effects such as drowsiness, itching, constipation and nausea.

Palliative treatment
Treatment that relieves symptoms, such as pain, but is not expected to cure the disease. The main purpose is to improve the patient's quality of life.

Patent ductus arteriosus
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.

The thin elastic-like sac that covers the heart.

Pertaining to the period immediately before and after birth.

After delivery.

Pertaining to the lungs and respiratory system.

Pulmonary artery
The large artery that receives blood from the right ventricle and carries it to the lungs.

Pulmonary hypertension
Abnormally high blood pressure in the arteries of the lungs.

Pulmonary valve
The heart valve between the right ventricle and the pulmonary artery. It consists of three flaps, or cusps.

Pulmonary vein
The vessel that carries oxygenated blood from the lungs to the left side of the heart. 

Radiofrequency ablation
The use of concentrated radio waves to heat and destroy the source of abnormal electrical signals, which can cause the heart to beat irregularly.

Red blood cells
Blood cells that help transport oxygen to all the tissues in the body.

The abnormal backflow of blood through a valve.

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. 


An artificial connection of blood vessel intended to redirect blood or other fluids.

One of the walls that divides the two chambers on the left side of the heart from the two chambers on the right.

Not inherited, occurring occasionally, in irregular instances.

The narrowing or constriction of a blood vessel or valve in the heart.

A device implanted in a vessel used to help keep it open.

A set of characteristics that tend to occur together and reflect the presence of a particular disease or an increased chance of developing a particular disease.

Systolic pressure
The pressure of blood inside arteries when the heart contracts. In a blood pressure reading, this is the top number.


Thromboembolic pulmonary hypertension
Caused by a blood clot in the lungs, thromboembolic pulmonary hypertension is a dangerous increase in blood pressure in the artery that carries oxygen-poor blood from the heart to the lungs.

Transesophageal echocardiogram
A type of echocardiogram in which sound waves are transmitted into the heart from a thin tube placed down the esophagus, behind the top chambers of the heart. The returning echoes from the surfaces of the heart are recorded.

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.


An opening, covered by membrane flaps, between two chambers of the heart or between a chamber of the heart and a blood vessel.

Pertaining to the blood vessels.

Any one of a series of vessels that carry blood from various parts of the body back to the heart.

One of the heart's two lower chambers that receive blood from the atria.

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.


White blood cells 
Blood cells needed in the destruction of viruses, bacteria and fungi that cause infection.


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- Sandra L. Fenwick, President and CEO

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