Cardiac Center

Glossary of Cardiac Terms

Jump To: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | R | S | T | U | V | W | X

A

Ablation

Elimination or removal. 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.

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.

Anastomosis

A surgical connection, often between two blood vessels.

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.

Anticoagulant

A medication that keeps blood from clotting.

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 left side 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). The head and neck vessels arise from this part of the aorta, directing blood from the heart; the remainder of the blood then goes down to the rest of the body.

Aortic regurgitation

Backwards leakage of blood from the aorta, through a weakened aortic valve, and into the left ventricle, sometimes resulting in stress in the left heart and inadequate blood flow to the body. It can be trivial, mild, moderate, or severe. Read more»

Aortic stenosis

Narrowing of the opening of the aortic valve (the valve that regulates blood flow from the left ventricle into the aorta). This leads to obstruction of the valve that can be mild, moderate, severe, or critical. Read more»

Aortic valve

The valve that regulates blood flow from the heart into the aorta.

Apnea

Cessation of breathing.

Arrhythmia (Also called dysrhythmia)

A fast, slow, or irregular heartbeat.

Arterioles

Small branches of arteries.

Artery

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

Arteriosclerosis

Also called atherosclerosis, and commonly called "hardening of the arteries," a variety of conditions caused by fatty or calcium deposits in the artery walls causing them to thicken.

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), which can be small, moderate, or large in size. Read more»

Atrial septum

The wall between the right and left atria (the two upper chambers of the heart).

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. Also called atrioventricular septal defect or endocardial cushion defect.

Atrium (atria plural)

One of two upper chambers in the heart.

Atrioventricular block

An interruption of the electrical signal between the atria and the ventricles.

Atrioventricular (AV) node

A cluster of cells between the atria and ventricles that regulates the electrical current and is the only normal electrical connection between the atria and ventricles.

B

Bacterial endocarditis

A bacterial infection of the valves or 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.

Beta blocker

A medication that limits the activity of epinephrine (a hormone that increases blood pressure).

Bicuspid

A valve that has two leaflets.

Biopsy

A procedure in which tissue samples are removed from the body for microscopic examination to establish a diagnosis.

Blood clot

A thick, gelled mass of blood.

Blood pressure

The force or pressure exerted by the heart when pumping blood; the pressure of blood in the arteries.

Blood pressure cuff

A device usually placed around the upper portion of the arm to measure blood pressure.

Brady

Prefix meaning slow.

Bradycardia

Abnormally slow heartbeat.

Bundle-branch block

A condition in which one or more of branches of the heart's electrical system is unable to normally conduct the electrical signal in the ventricles.

C

Calcium channel blocker

A medication that lowers blood pressure.

Capillaries

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

Cardiac

Pertaining to the heart.

Cardiac arrest

The stopping of 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. The evaluation includes measuring pressure and oxygen amounts in each chamber as well as angiography.

Cardiac output

The amount of blood that goes through the circulatory system in one minute.

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

Changing an abnormal heartbeat into a normal one. This can occur spontaneously, by giving a medication, or by applying an electrical shock to the chest.

Carotid artery

The major arteries in the neck that arise from the aortic arch and supply blood to the brain.

Catheter

A small, thin tube; may refer to a tube used during a cardiac catheterization procedure to inject dye, obtain blood samples, and measure pressures inside the heart; may also refer to a small tube used to help drain the bladder during and after a surgical procedure.

Cholesterol

A waxy substance that is produced by the human body. It is also found in animal fats, shellfish, and in dairy products (such as beef, chicken, pork, butter, milk, cheese, and eggs). It is an important part of cell membranes as well as a building block for certain hormones.

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.

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.

Coarctation of the aorta

A congenital heart defect that results in narrowing of the aorta. Read more»

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.

Computerized tomography scan (Also called CT or CAT scan)

A non-invasive procedure that takes cross-sectional images of the brain or other internal organs; to detect any abnormalities that may not show up on an ordinary x-ray.

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 enough blood to meet the body's needs, 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.

Coronary arteries

Two arteries that come from the aorta to provide blood to feed the heart muscle.

Cyanosis

Insufficient oxygen in the blood. Patients with this can sometimes appear blue or purple, especially in or around the mouth.

Cyanotic

Appearing blue, due to insufficient oxygen in the blood.

D

Defibrillator

An electronic device used to establish normal heartbeat.

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 can be connected correctly; occurs due to an abnormality in heart development during pregnancy.

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.

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 the blood flowing in the 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.

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.

Dysrhythmia

An abnormal heart rhythm.

E

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)

Also called cardiac ultrasound
A procedure that evaluates the structure and function of the heart by using sound waves (ultrasound) recorded on an electronic sensor which produce a moving picture of the heart and heart valves.

Edema

Collection of extra fluid in tissues that can lead to swelling; seen in congestive heart failure.

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 stress.

Electrophysiological study (EPS)

A cardiac catheterization to study electrical current in patients who have arrhythmias.

Endocardium

The membrane that covers the inside surface of the heart.

Endocarditis

An infection of the valves and interior surfaces of the 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.

Enlarged heart

A condition of the heart in which it is larger than normal.

Epicardium

The membrane that covers the outside of the heart.

Exercise electrocardiogram (ECG or EKG)

A test to assess the cardiac rhythm and function by having the patient exercise on a treadmill or bicycle.

F

Failure to thrive

Failure to grow and gain weight; often due to increased energy expenditure with congenital heart disease.

Fibrillation

Rapid, disorganized, and ineffective 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

Rapid and organized but 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 inferior vena cava to the pulmonary artery, allowing oxygen-poor (blue) blood from the body to flow directly into the lungs. This is performed after a Glenn shunt, where the superior vena cava is attached to the pulmonary artery.

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. About 25-30 percent of all adults still have it patent, or open.

G

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.

H

Heart attack (Also called myocardial infarction)

Occurs when one of more regions of the heart muscle experience a severe or prolonged decrease in oxygen supply caused by a blocked blood flow in a coronary artery to the heart muscle.

Heart block

Slowed or interrupted electrical impulse to heart muscles. Same as atrioventricular block.

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.

High blood pressure (Also called hypertension)

Blood pressure that is above the normal range.

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.

Hypertrophic obstructive cardiomyopathy

(Also called HOCM, hypertrophic cardiomyopathy, asymmetrical septal hypertrophy/ASH, or idiopathic hypertrophic subaortic stenosis/IHSS). Abnormally thickened and enlarged heart muscle that can cause impeded blood flow as well as lethal dysrhythmias. Frequently due to a genetic abnormality.

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 small mitral valve, left ventricle, and aorta. Read more»

Hypotension

Low blood pressure.

Hypoxemia

Abnormally low oxygen content in the blood.

Hypoxia

Abnormally low oxygen content in the organs and tissues of the body.

I

Immunosuppressive medications

Medications that suppress the body's immune system; used to minimize rejection of transplanted organs.

Implantable cardioverter-defibrillator

An electronic device that is surgically placed in the patient's body and connected to the heart in order to detect and to interrupt potentially lethal dysrhythmias.

Implantable loop recorder

An electronic device that is surgically placed in the patient's body and connected to the heart in order to detect dysrhythmias.

Incision

A cut made with a surgical instrument during an operation.

Inferior vena cava

The large blood vessel (vein) that returns blood from the legs and abdomen to the heart.

Insufficiency

A valve deformity that allows the blood to leak backwards when the valve is closed; also called regurgitation.

Ischemia

Decreased flow of oxygenated blood to an organ due to obstruction in an artery. It can lead to tissue damage and, if prolonged, death or infarction of tissue in the organ.

Ischemic heart disease

Coronary artery disease or coronary heart disease caused by narrowing of the coronary arteries and decreased blood flow to the heart.

J

Jugular veins

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

K

Kawasaki disease

An immune system disorder causing inflammation of the heart, particularly the coronary arteries. It is also causes rash, swollen lymph nodes, conjunctivitis, red and swollen hands and feet, and inflamed lips and tongue.

L

Left atrium

The upper left-hand chamber of the heart. It receives oxygen-rich (red) blood from the lungs via the pulmonary veins, 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. The left ventricle must be strong and muscular in order to pump enough blood to the body to meet its requirements.

Lesion

An injury or wound.

Lipid

A fatty substance in the blood.

Lipoproteins

Transporters of fatty substances in the blood.

Low density lipoprotein (LDL)

The primary cholesterol-carrying substance in the body. In large amounts, it accumulates inside arteries and can participate in damage to the arterial walls.

Lumen

The hollow area inside a blood vessel.

M

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.

Marfan syndrome

A genetic disorder which 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. Patients with a mechanical valve require anticoagulation medication to prevent clots from forming on the 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.

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 can cause backward flow of blood from the left ventricle into the left atrium.

Mitral valve regurgitation

Backwards leakage of blood from the left ventricle, through a weakened mitral valve, and into the left atrium, sometimes resulting in stress in the left heart and inadequate blood flow to the body. It can be trivial, mild, moderate, or severe.

Mitral valve stenosis

Narrowing of the opening of the mitral valve (the valve that regulates blood flow from the left atrium into the left ventricle). This leads to obstruction of the valve that can be mild, moderate, or severe.

Monounsaturated fats

Dietary fats, such as olive oil or canola oil, that may lower LDL cholesterol levels.

Murmur

A blowing or rasping sound made by turbulent blood flow heard while listening to the heart. It may or may not indicate problems within the heart or circulatory system. Read more»

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 a blocked blood flow to the heart muscle that leads to death of heart tissue.

Myocardial ischemia

Insufficient blood flow to part of the heart that can lead to damage of heart tissue.

Myocarditis

Inflammation of the heart muscles, usually caused by a viral infection.

Myocardium

The muscular layer of the heart.

N

Noninvasive procedure

A diagnostic effort or treatment that does not require entering the body or puncturing the skin.

O

Obesity

Overweight by 30 percent of the ideal body weight.

Occluded artery

An artery that is narrowed by plaque or other obstruction that impedes blood flow.

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 94 to 100 percent.

Oxygen saturation

The extent to which the hemoglobin is saturated with oxygen. (Hemoglobin is a protein in the red blood cells 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 94 to 100 percent. The oxygen saturation of the blood returning to the heart after delivering oxygen to the body is about 75 percent.

P

Pacemaker

An electronic device that is surgically placed in the patient's body and connected to the heart to regulate the heartbeat.

Palpitation

An abnormal sensation in the chest caused by an irregular heartbeat.

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. Read more»

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. Approximately 25 to 30 percent of all adults have a patent foramen ovale.

Pericardial effusion

A build up of excess fluid between the heart and the membrane that surrounds it, often due to inflammation.

Pericarditis

An inflammation or infection of the sac which surrounds the heart that can create a pericardial effusion.

Pericardiocentesis

A diagnostic and therapeutic procedure that uses a needle to draw fluid from the pericardium.

Pericardium

The membrane that surrounds the heart.

Plaque

Deposits of fat or other substances attached to the artery wall.

Platelets

Cells found in the blood that assist in clotting.

Polyunsaturated fat

A type of fat found in vegetable oils and margarines that does not appear to raise blood cholesterol levels.

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.

Prophylaxis

Prevention.

Prostaglandin E1

An intravenous medication used to keep a patent ductus arteriosus from closing and to preserve blood flow to the lungs.

Pulmonary

Pertaining to the lungs and respiratory system.

Pulmonary artery

The blood vessel connecting the right ventricle to the lungs, allowing oxygen-poor (blue) blood to receive oxygen.

Pulmonary edema

A condition in which there is fluid accumulation in the lungs caused by an incorrectly functioning heart. Seen in congestive heart failure.

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 94 to 100 percent.

R

Radioisotope

A radioactive material injected into the body so that a nuclear scanner can make pictures.

Regurgitation

Backward flow of blood caused by a defective heart valve-also called insufficiency.

Renal

Pertaining to the kidneys.

Rheumatic fever

A disease caused by a strep infection that may damage the heart valves. It can also cause rashes, joint pain and swelling, nodules on the arms, and a movement disorder.

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

A condition, element, or activity that may adversely affect the heart.

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.

S

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 connection to allow blood flow between two locations. It can be congenital or it can be placed surgically.

Sinus node

The cells that produce the electrical impulses that cause the heart to contract. The natural pacemaker of the heart.

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.

Sphygmomanometer

An instrument used to measure blood pressure.

Stent

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

Stenosis

Narrowing or constriction of a blood vessel or valve in the heart or circulatory system.

Stethoscope

An instrument used to listen to the heart and other sounds in the body.

Sternotomy

A surgical incision made in the breastbone, or sternum.

Sternum

The breastbone.

Stress

Mental or physical tension that results from physical, emotional, or chemical causes.

Stroke

The sudden disruption of blood flow to the brain.

Subclavian artery

A blood vessel that branches from the aortic arch and takes oxygen-rich (red) blood to the arms.

Subclavian flap

A surgical procedure performed to repair coarctation of the aorta, using part of the left subclavian artery as a patch to enlarge a narrowed aorta.

Superior vena cava

The large vein that returns blood to the heart from the head and arms.

Supraventricular tachycardia

A fast abnormal heart rate that originates in the atria, but does not start in the sinus node.

Syncope

Fainting caused by insufficient blood supply to the brain. Near-syncope is light-headedness due to the same cause.

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.

T

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. Thickening, or hypertrophy, of the right ventricle occurs as the right ventricle copes with obstruction to blood flow. Read more»

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.

Trans fat

Vegetable oil that has been treated with hydrogen in order to make it more solid and give it a longer shelf life.

Transesophageal echocardiography (TEE)

A diagnostic test that uses a long tube guided into the mouth and esophagus to evaluate the structures inside the heart with sound waves.

Transplantation

Replacing a damaged organ with one from a donor.

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. Read more»

Transtelelphonic monitor

A small heart monitor that is worn to record the heart rhythm when activated by the patient or parent. There are two main kinds: loop recorders, which record continuously but store the heart rhythm only when activated, and event (non-looping) recorders, which record and store only when they are placed on the patient's chest and activated.

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.

Tricuspid valve stenosis

Narrowing of the opening of the tricuspid valve (the valve that regulates blood flow from the right atrium into the right ventricle). This leads to obstruction of the valve that can be mild, moderate, or severe.

Triglyceride

A fat-like substance found in the blood.

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. Read more»

U

Ultrasound

A diagnostic tool used to evaluate organs and structures inside the body with high-frequency sound waves.

V

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

Repairing a heart valve by surgery or by using a catheter with a balloon.

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 syncope

A sudden drop in blood pressure, with or without a decrease in heart rate, which is caused by a dysfunction of the nerves controlling the heart and blood vessels.

Vein

A blood vessel that carries blood from back into the heart.

Ventricle

One of the two lower chambers of the heart.

Ventricular fibrillation

A condition in which the ventricles contract in rapid, unsynchronized, and ineffective rhythms and cannot pump blood into the body.

Ventricular septal defect

An abnormal opening in the wall between the right and left ventricles, which can be small, moderate, or large in size. Read more»

Ventricular tachycardia

A condition in which the ventricles beat very quickly.

W

Wolff-Parkinson-White syndrome

An extra electrical pathway that connects the atria and ventricles and can cause supraventricular tachycardia.

X

X-ray

A diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film.