Click on a highlighted category to view a list of common medical terms. Clicking on the term will reveal the definition. The entire glossary may also be downloaded by clicking on the above print icon.
The main artery coming off the heart which carries blood from the heart to the body.
The valve between the left ventricle and the aorta.
A blood vessel that carries oxygenated blood (red blood) from the heart out to the body.
Plural of atrium. The left atrium pumps oxygenated blood into the left ventricle. The right atrium pumps deoxygenated blood into the right ventricle.
An upper chamber of the heart where blood collects before passing to the ventricle.
(of a valve) Having two cusps, or leaflets.
Blood which is returning from the body to the heart and so pumped to the lungs, where it will pick up oxygen and become red blood.
Normal dilation of the heart's cavities during which they fill with blood.
The thin, inner membrane that lines the cavities of the heart.
The thin, inner membrane that lines the cavities of the heart.
The digestive tube that begins in the back of the oral cavity and extends down to the stomach.
Multi aortopulmonary arteries. A number of additional arteries come from the aorta and supply the lungs with blood.
A blood vessel that connects the pulmonary artery to the aorta and allows red (oxygenated) blood to return from the aorta back to the lungs.
To do with the lungs.
The blood vessel that takes blood from the heart to the lungs.
Blood which has picked up oxygen from the lungs and travels through the left side of the heart to be pumped around the body.
The wall between the left and right chambers of the heart.
The breast bone.
The portion of the heart cycle during which the heart muscle is contracting and squeezing blood out.
The valve between the right atrium and right ventricle which has three cusps.
A blood vessel that carries un-oxygenated blood (blue blood) from the body back to the heart.
Large veins returning deoxygenated blood into the right side of the heart, where it will be pumped into the lungs for oxygenation.
Pumping chambers of the heart - the left ventricle pumps blood out to the body and the right ventricle pumps blood to the lungs.
The cells in the body that help fight infection.
A document you create to designate who will make healthcare decisions and states your wishes if you become unable to make your own healthcare decisions.
Build up of proteins in the body which can be deposited into the heart muscle, among other organs.
Chest pain brought on by heavy activity or exertion because of inadequate blood supply to the heart. Pain is relieved by rest.
A narrowing of the aorta which restricts oxygen-filled blood from pumping out of the heart into the body.
Out of rhythm - the heart is beating too fast, too slowly, or irregularly.
Blood vessels that carry blood away from the heart.
(arrhythmogenic right ventricular cardiomyopathy or arrhythmogenic ventricular dysplasia ARVD or right ventricular cardiomyopathy ) A form of cardiomyopathy in which the heart muscle cells become disorganized and are replaced by fatty tissue.
Asymmetrical septal hypertrophy. This term has been replaced by the current term, hypertrophic cardiomyopathy, because the hypertrophy can occur in any part of the lower heart.
Disease in which fatty deposits build up on the inner walls of the arteries and cause inflammation which causes narrowing or blockage that can lead to a heart attack; commonly known as "hardening of the arteries".
Blocked or missing, most commonly in reference to blood vessels.
Irregularly slow heart beat.
Inflammation of the small breathing tubes (bronchioles) in the lungs.
Commonly refers to "Candida Albicans" which can cause a yeast or fungal infection.
Relating to the heart.
Doctor who specializes in the heart.
A disease of the heart muscle.
A fatty substance that comes mostly from eating certain foods which your body uses for normal regulation of cells; when too much cholesterol builds up in the body, it can lead to atherosclerosis.
When the heart cannot supply the body with enough oxygenated blood to stay healthy. CHF can result when heart muscle cells are abnormal or overworked.
A blue color of the skin due to not enough oxygen in the blood stream.
The muscle separating the abdominal and chest cavities, it assists in breathing.
Enlarged or stretched.
The chambers of the heart become enlarged or stretched out.
Abnormal or difficult breathing.
Swelling from build up of extra fluid.
The percentage of total blood pumped out of the heart during one beat. It is the amount of blood pumped out divided by the amount of blood remaining in the heart at the end of one beat.
A change in mental condition, which can be the result of many things including toxins that normally circulate in the bloodstream that are not cleared properly by the liver and alter brain function.
An infection of the lining of the heart.
The cause of a disease.
What happens when the heart cannot supply the body with enough oxygen in the blood to stay healthy. Heart failure can result when muscle cells are abnormal or overworked.
A murmur is a sound made by blood moving through the heart: sometimes, but not always, this can be caused by a heart defect.
The heart's electrical charges are delayed or do not pass from the uppers chambers to the lower chambers; it is classified according to the level of impairment - first-degree heart block, second-degree heart block, or third-degree (complete) heart block.
Excessive iron in the blood which can be deposited in the heart muscle, among other organs.
High blood pressure.
The heart muscle thickens and becomes stiff.
Another name for hypertrophic Cardiomyopathy, where part of the septal wall periodically blocks part of the outflow of blood from the heart.
Low blood sugar.
Failure of an organ or body part to grow and develop fully.
Decreased muscle tone.
Of unknown origin.
Idiopathic hypertrophic subaortic stenosis, a form of hypertrophic cardiomyopathy where the hypertrophy is located under the aortic valve and creates a narrowing (stenosis) that makes it difficult for blood to exit the heart.
Occurs when the body has difficulty breaking down (metabolizing) certain nutrients, i.e. fats, proteins, and carbohydrates.
A document created to specify which kinds of medical treatment you would accept or reject in certain situations; also called a "living will".
Insufficient blood to an organ, caused by narrowing of an artery from blockage, spasm of the wall of the artery, or compression from muscle surrounding the artery.
Type of white blood cell formed in lymphatic tissue; lymphocytes normally comprise about 25% of all white blood cells and play a key role in triggering the body's immune response.
An infection of the lining of the brain.
Excessive acidity in the blood.
The powerhouses located in each cell, providing much of the energy necessary for the cells to function.
Leak in the mitral valve that allows blood to flow backwards from the left ventricle to the left atrium.
Inflammation of the heart.
Physicians who treats disorders of the nervous system.
Not related to insufficient blood flow to the heart.
Forceful irregular heartbeats.
The causes of a disease.
Physician trained to care for children with heart disease.
Pediatric cardiothoracic Unit.
Pediatric Cardiac Intensive Care Unit.
Inflammation of the tissue (pericardium) that surrounds the outside of the heart.
Membranous sac enclosing the heart.
An accumulation of fluid in the pericardial sac, the outer covering of the heart, which, if large, may need to be drained with a needle (pericardiocentesis).
Someone who helps a patient return to normal physical functioning, especially after surgery.
Pediatric Intensive Care Unit.
A disorder that occurs after the Fontan Procedure and results in loss of protein molecules from the blood into the intestine and can cause diarrhea. If enough protein is lost, the low protein levels in the blood lead to leakage of fluid into the tissues, causing swelling of the abdomen, face and legs.
Infection of the lung.
Describes a medicine or procedure intended to prevent illness.
Physician who specializes in treating disorders of mental health.
High blood pressure in the arteries that supply the lungs.
A narrowing of the valve to the lungs.
A type of heart muscle disease that is caused by an inability of the heart muscle to relax properly because it is too stiff.
A virus that causes bronchiolitis.
The heart's natural pacemaker that controls how fast the heart beats.
Short for the oxygen saturation level, a measurement of the amount of oxygen carried by the blood cells.
A natural or artificially created passageway that connects one part of the circulation to another. Shunts are often used to create more blood flow to the lungs by directing blood from the aorta to the pulmonary artery.
A mirror image arrangement of the organs, so that the heart and stomach are on the right and the liver and spleen on the left.
Professional who can help patients with social, financial, and support systems.
Very fast heart beat that starts in the atrium of the heart.
Fast heart beat.
Excess pressure in the veins that leads to leakage of fluid into the tissues.
Any of several forms of a gene, usually arising through mutation, that are responsible for hereditary variation.
Pertaining to different gene constitutions within the same species, antigenically distinct (i.e. a heart transplant from a genetically different human donor).
Structures found in the nucleus of the cell which contain the genes; chromosomes come in pairs, with normal human cells containing 46 chromosomes.
Describes a condition which is present at birth.
Detects a mutation in a gene known to cause a particular disorder. Direct DNA analysis can be accomplished when the gene in question is known and the genetic changes can be found and interpreted.
Biochemical molecule that makes up our genes; it encodes the genetic information necessary for the organization and functioning of most living cells and controls the inheritance of characteristics.
Looks at submicroscopic pieces of chromosomes to detect missing or extra chromosomal material at the region specific to the FISH assay.
Basic units of heredity consisting of segments of DNA; genes code for specific proteins that perform the functions of the body and lead to particular characteristics.
A medical doctor who specializes in the diseases of inheritance.
When not all carriers of a genetic mutation demonstrate symptoms of disease.
Takes a microscopic picture of the chromosomes in order to reveal the size, shape, and number of chromosomes in the cells. This method can detect large extra, missing, or abnormal positions of chromosome pieces. Not all genetic abnormalities can be detected by a karyotype.
"A gene-hunting technique" which maps genes for disease in relation to their positions along the chromosome in order to locate a disease-causing mutation specific to a family. This test requires several members of a family with a high risk for a genetic condition and can be used when the exact location of the mutation is unknown. This type of testing is usually performed in research laboratories.
A genetic change or alteration that causes disease.
Angiotensin Converting Enzyme (ACE) inhibitors are a group of drugs used to dilate blood vessels and make it easier for the heart to pump blood. They have also been shown to block some of the hormones in the blood that are known to worsen heart failure. Common ACE inhibitors include captopril, enalapril, lisinopril, monopril. Common side effects include high potassium in the blood, low blood pressure, low white blood cell count, and kidney or liver abnormalities.
Intravenous anti-arrhythmic drug used in rhythm disorders with fast heart rates.
A medicine that lowers blood pressure and decreases the workload on the heart. ACE inhibitors, described above, are a class of afterload-reducing medications.
A weak diuretic (water pill) that prevents urinary potassium loss; also used to block a kidney hormone (aldosterone) to decrease scar formation within the heart muscle.
A drug used to treat heart rhythm disorders such as SVT, atrial flutter or junctional/ ventricular tachycardia.
Medication given to stop pain.
Drug designed to block the effects of angiotensin which will help to dilate blood vessels and allow the heart to pump against lower resistance (more dilated) blood vessels. Common examples are Losartan, valsartan, candesartan. Common side effects include diarrhea, muscle cramps, dizziness, and elevated blood potassium and kidney abnormalities
A blood-thinning medication given to help prevent blood clots from forming in the heart or blood vessels. There is a risk of clots forming inside the heart of children whose heart does not contract well. Anticoagulation medications, also known as blood thinners, prevent blood clotting. Some drugs such as warfarin (coumadin), heparin or enoxaparin, act by inhibiting the activation of clotting factors. These drugs require careful monitoring with regular blood testing. Other drugs act by inhibiting clot-forming cells (platelets) and include aspirin and dipyridamole.
Medications that block high levels of adrenaline in the blood stream to help improve the strength of the heart muscle. Beta-blockers slow the heartbeat and reduce the work of contraction of the heart muscle. Slowing the heart rate can help keep a weakened heart from overworking. In some cases, beta-blockers allow an enlarged heart to become more normal in size. Common beta-blockers include atenolol, carvedilol, metoprolol and nadolol. Common side effects include dizziness, low heart rate, low blood pressure and fluid retention.
Diuretic or "water pill" and is a "cousin" of furosemide (lasix).
(also known as calcium antagonists): Improve the filling of the heart by reducing the stiffness of the heart muscle. These are used in patients with chest pain or breathlessness. Calcium channel blockers can cause excessive slowing of the heart rate and lower blood pressure. Common calcium channel blockers are verapamil and diltiazem. Calcium channel blockers are not commonly used in patients with DCM, as they may make the heart failure worse.
A drug (ACE-inhibitor) used to treat high blood pressure and heart failure. It decreases the levels of certain chemicals that act to tighten the blood vessels, so blood flows through more dilated blood vessels at lower pressure which allows the heart to pump using less energy, thereby reducing its workload.
Hormones secreted by the adrenal gland which have many effects. Corticosteroids can be manufactured and in high doses are used as immunosuppressants.
Brand name for warfarin, an anti-coagulant or "blood thinner".
A medicine given to increase the strength of heart contraction or slow down the heart rate. Used appropriately in patients with normal kidney function, side effects are minimal. Drug toxicity can cause vomiting, abnormally slow heart beat, and abnormal conduction.
Anti-platelet medication or "blood thinner".
Medications that help the kidneys pass more water, so reducing excess fluid in the organs, especially the lungs. Diuretics, sometimes called "water pills," reduce excess fluid in the lungs or other organs by increasing urine flow. The loss of excess fluid reduces the workload of the heart, reduces swelling of the legs and liver and helps children breathe more easily. Diuretics can be given either orally or intravenously.
Diuretic or "water pill".
Dobutamine, dopamine, epinephrine, norepinephrine : Sympathomimetic agents that are given by a continuous intravenous infusion used to increase blood pressure and the strength of heart contractions. Common side effects include increased heart rate, arrhythmias and for some, depending on the dose, excessive constriction of the arteries.
A drug (ACE inhibitor) given to lower blood pressure and treat heart failure.
Anticoagulation medication or "blood thinner".
A drug given directly into a vein which thins the blood to reduce the risk of blood clots (an anticoagulant).
Are used to help the heart contract more vogorously. Intravenous ionotropic medications are used to support children who have severe heart failure and do not respond adequately to oral medications.
Medicines administered through an intravenous catheter directly into the bloodstream.
Phosphodiesterase inhibitor that improves heart contraction and decreases the work of the heart by relaxing the arteries. A common side effect is low blood pressure.
A drug used to keep the ductus arteriosus open which may be necessary in certain forms of congenital heart disease (i.e. hypoplastic left heart syndrome, critical aortic stenosis, and severe coarctation of the aorta or pulmonary atresia).
Arrhythmia medication used to treat certain forms of rapid heart beat such as SVT or atrial flutter.
Weak diuretic (aka aldactone) that prevents potassium wasting in the urine (helps maintain normal blood potassium level when on other diuretics like lasix).
Blood hormone that increases blood pressure and improves blood flow to the central organs (heart, lungs, brain). Common side effects include excessive constriction of the arteries, low sodium and decreased blood flow to the kidneys and bowel.
Arterial Blood Gas. Blood drawn from an artery used to measure the amount of oxygen and carbon dioxide in the blood.
An X-ray movie of blood as it moves through the heart and blood vessels after contrast (dye) is injected through a catheter positioned in the heart or nearby blood vessels.
Helps to examine the blood vessels and chambers of the heart. Dye that is visible on an X-ray is injected through the catheter. The flow of the dye can be followed on a video monitor and recorded. The movement of the dye is tracked to assess for "holes" in the heart, abnormal blood pathways through the heart or narrowed blood vessels near the heart.
Removal of a small piece of tissue usually from the heart for microscopic examination (the heart will not miss this very small piece of tissue).
A waste product normally excreted by the kidney; the blood level represents how well the kidneys function.
A tube which is put into the heart via a vein or artery. It is used to help diagnosis by measuring pressures very accurately, or can treat a problem such as widening an artery or closing a hole.
An invasive procedure that involves inserting a thin, flexible, plastic tube (catheter), through a tiny incision in the skin, into a blood vessel (either in the neck or in the groin area) and threading it into the heart or the coronary arteries. The catheterization approach can be used for a range of diagnostic and therapeutic procedures, including measuring blood pressure within the heart and the amount of oxygen that is in the blood in each chamber, as well as determining the pumping ability of the heart muscle.
Uses a small amount of radiation to take a picture of the heart and lungs. Chest X-rays show the size and shape of the heart, the major blood vessels and bones in the chest, and whether there is any fluid present or any abnormalities in the lungs. X-rays can be done at the bedside if the patient cannot be moved safely but are usually performed in the radiology department of the hospital and take just a few minutes to complete.
Computed Axial Tomography. A fancy X-ray scanner which uses computers to generate a three-dimensional image.
Performed as part of the echocardiogram and measures the speed and direction of blood through the valves and chambers of the heart as well as the blood vessels taking blood to or away from the heart.
Short for electrocardiogram - for measuring the electrical activity of the heart.
Short for echocardiogram. An echocardiogram uses high frequency sound waves to produce moving images of the beating heart on a video screen. The echocardiogram usually lasts about 45 minutes to an hour. These images allow the cardiologist to measure muscle thickness, pumping ability, chamber size, and valve movement. Pressures inside the heart chambers and major vessels can also be estimated. The study may be done with the use of oral sedation to help optimize study quality especially in uncooperative children under age 2 years.
A recording of the electrical activity in the brain.
Tests for abnormal electrical conduction pathways which increase susceptibility to arrhythmias, the effectiveness of anti-arrhythmic drugs, and the need for an implantable cardioverter defibrillator. The study uses fine wires inserted through veins in the groin area and threaded to the heart - a similar approach to cardiac catheterization. Electrical stimuli are applied through these wires to map the hearts' electrical system and susceptibility to abnormal rhythms.
Test done in the outpatient setting to evaluate the heart's reserve while the patient is exercising, usually walking on a treadmill or pedaling a stationary bike. The child's blood pressure, heart rhythm, oxygen saturation and breathing are measured during different degrees of exertion.
Records the heart rhythm continuously for 24 hours on a cassette tape. The test is used when an abnormal heart rhythm is suspected. Your child will wear the monitor home and take it off 24 hours later.
A blood test to measure how fast the blood clots; used to adjust the amount of anticoagulant (coumadin) prescribed.
Electrical wires for recording the heart rhythm.
Uses radio waves inside a large magnet to generate a 3- dimensional image which allows doctors to evaluate the heart and blood vessel anatomy, function, and flow dynamics. This is a non-invasive test and does not involve the use of X-rays. Sometimes sedation is required since patient movement can cause image artifact. A typical MRI takes about 45-60 minutes to complete.
(Multiple Gated Acquisition or radionuclide ventriculogram): Similar to an echocardiogram, but offers a more accurate measurement of how well the heart functions as a pump through the use of injected radioactive contrast material. It measures how much blood the heart pumps, or "ejects," with each contraction and how quickly that blood is ejected.
Measures lung function. A child breathes into a tube attached to a measuring device that shows how well the lungs work and often times compliments an exercise stress test. Sometimes PFTs are done with bronchodilators (i.e. albuterol inhaler) to see if these agents improve lung function.
Measures heart function; also known as a MUGA scan (see above description).
Removal of small piece of body muscle for laboratory analysis. This is a surgical procedure and muscle is usually taken from the leg (in small children) or arm.
Allows doctors to see how the blood flows through the heart muscle. Thallium is a radioactive substance that only travels to the heart muscle cells receiving blood, thereby identifying areas of the heart that at high risk for a heart attack. The thallium is injected through an intravenous line. The test is usually performed in two stages, one during exercise on a treadmill and one at rest. This allows doctors to see how blood flows through the heart while working hard (on the treadmill) and when resting. Aside from the injection, this is a non-invasive test. The imaging can take up to 25 minutes. However, because it takes time for the thallium to circulate, the entire test may take upwards of five hours.
The transplant of an organ or tissue from one individual to another of the same species with a different genotype. A transplant from one person to another, but not an identical twin, is an allograft.
A substance that is produced by the immune system in response to specific foreign material, thereby helping the body to fight infection.
Substances foreign to the body causing the immune system to form antibodies.
Special white blood cells responsible for the body's immunity; B cells play a central role in antibody production.
An immunosuppressant drug of major importance in fighting organ rejection.
Removal of a tiny piece of heart tissue for analysis, including testing for organ rejection; also called a cardiac biopsy.
Another term used for the donor organ, both before and after transplantation.
Body's defense against disease.
Agents that act to suppress the body's natural immune responses, helping to decrease the chance of rejection for transplanted patients.
To reduce to body's ability to protect itself against infection and foreign substances.
Infections that prey on those with compromised immune systems, such as persons with AIDS or transplant recipients taking immunosuppressant medicines.
The most common surgical procedure for attaching the new heart.
Therapy used to combat organ rejection by increasing one's dosage of the immunosuppressant prednisone.
Episode wherein the immune system identifies a transplanted organ as an antigen or foreign item and rallies an immunologic attack against it.
Referring to transplantation of organs from one species into another.
Electric current or radio-frequency energy can be used via a catheter to destroy tissue in the heart which is causing an arrhythmia (abnormal heart rhythm).
Automatic internal cardioverter defibrillator; electronic device that helps control the heart's rhythm.
Using a tube (catheter) to reach a narrow (stenosed) part of the heart such as an artery or valve and making it bigger by inflating a balloon on the end of the catheter.
A tube (catheter) is put into the heart and a balloon inflated on the end of it to make a hole, or increase the size of a hole, in the wall (septum) of the heart.
Making the pulmonary artery narrower with a band to reduce blood flow to the lungs.
Mechanical device that helps do the work of both heart chambers.
Blalock-Taussig shunt. A hollow tube that connects the aorta to the pulmonary artery to supply extra blood flow to the lungs.
Using a machine that provides blood flow and oxygen to the body so that the blood flow bypasses the heart and lungs during surgery.
Machines that do the work of the heart by using a mechanical pump to deliver blood to the body.
Hollow, flexible drainage tubes used to drain away fluid, blood or air from the space between the lungs and the chest wall (the pleural space) and allow full expansion of the lungs.
The delivery of air into the lungs under constant pressure to keep the small airways open, used especially before completely off ventilation.
(extracorporeal membrane oxygenation) : A by-pass machine which can be used as a short-term cardiac assist device used either to rest the heart until it recovers or to support the circulation for the critically ill child waiting for a donor heart. This device is similar to the cardiopulmonary bypass machine used during open-heart surgery. It mechanically pumps oxygenated blood into the circulation and helps circulate blood through the body.
A soft flexible tube that is placed through the skin into the stomach to permit direct delivery of food and fluids.
The superior vena cava, which normally brings blood back to the right side of the heart, is connected to the pulmonary artery, so the venous blood is delivered directly to the lungs, bypassing the right ventricle.
Putting in human tissue - such as a valve, artery, or heart.
(implantable cardioverter-defibrillator) : An electronic device installed inside the body to provide an electrical "shock(s)" to the heart to stop an abnormal fast heart rhythm and return the heart to a normal rhythm. Also known as an AICD (automatic implantable cardioverter defibrillator).
A therapeutic device used to encourage and measure breathing strength after an operation.
The placement of a tube through the nose or mouth into the windpipe (trachea) to facilitate mechanical ventilation.
(Intra-Venous) Antibiotics directly into the blood.
Drugs given directly into the blood stream.
Used to take impurities from the blood when the kidneys are not working properly.
Are specifically designed to take over the function of the heart's left ventricle, while BiVentricular Assist Devices (BIVADs) offer support for both ventricles. In one type of LVAD, the pumping device is surgically implanted in the chest, while the battery and controller remain outside the body (external), worn on a belt. A tube placed in the left ventricle diverts blood from the heart to the pump. The pump then propels the blood back into the aorta - with enough force to be distributed adequately throughout the body.
A machine used to supply a controlled flow of oxygen and air into the lungs.
Involves the removal and examination of a piece of muscle tissue or skin cells. This tissue is sent to a pathologist for microscopic examination. Muscle biopsy plays an integral role in the evaluation of the person with neuromuscular disease.
A hollow, flexible tube inserted into the nose down through the esophagus into the stomach used for feeding or medication administration.
Sometimes used to help increase the amount of oxygen in the blood stream and to reduce the heart's workload.
A small battery-powered implantable device (generator) placed under the skin and joined to the heart by wires, which electrically stimulates the heart to contract and pump blood throughout the body. The wires (leads) are either connected directly to the surface of the heart (epicardial leads) or threaded through veins into the heart (transvenous leads). The devices monitor the heartbeat and help the heart to beat in a regular rhythm. Small electrical charges travel from the pacemaker, through the wire, to an electrode placed in the heart wall.
A medical device (pacemaker) designed to regulate the electrical activity of the heart. It either stimulates or regulates the hearts electrical activity when the rate is not fast enough.
Replacing the child's aortic valve with his or her own pulmonary valve and implanting another valve to replace the pulmonary valve.
A surgery that is performed to remove thickened muscle of the septum (the wall dividing the two sides of the heart) when that muscle has narrowed the pathway from the ventricle into the aorta obstructing the blood flow from the heart.
A short, metal mesh tube. Using balloon dilation this is expanded into a narrow artery to hold it open.
A surgical procedure that connects blood returning from the body directly to the pulmonary arteries, bypassing the right side of the heart.
IV feeding that provides a patient with all the fluid and essential nutrients when they are unable to feed by mouth.
A hole cut into the windpipe (trachea) to help breathing.
Food is given through a tube that runs from the nose directly into the stomach (NG tube, nasogastric tube).