Glossary of Common Terms Used In Pediatric Cardiology
ABG (arterial blood gas): a test that tells how much oxygen is in the blood and how well the child is breathing.

Aneurysm: a bulging of the wall of an artery, vein, or wall of the heart.

Angiocardiography: a specialized x-ray of the heart. A fluid that shows up on xray is injected in to a vessel or chamber of the heart to make a detailed picture.

Anoxia: no oxygen.

Anticoagulant: medication used to prevent blood clots or stabilize existing blood clots. Also commonly called a blood thinner.

Aorta: the main artery that supplies the blood and oxygen to the body. It usually comes off the left ventricle (main pumping chamber).

Aortic valve: the valve between the aorta and the left ventricle (main pumping chamber). The aortic valve usually has three leaflets.

Arrhythmia: an abnormal pattern of the beating of the heart.

Atrial Septum: the muscular wall between the two collecting chambers of the heart (left atrium and right atrium).

Atrio-Ventricular Node (AV Node): part of the electrical (conduction) pathway of the heart that tells the ventricles when to beat (usually after the atria).

Atrium: one of the two upper chambers of the heart. The right atrium collects unoxygenated blood (blue blood) from the body. The left atrium collects oxygenated blood from the lungs.

Bacterial Endocarditis: an infection of the inner layer and/or valves of the heart, caused by bacteria.

Blood Pressure: the pressure of the blood in the arteries. Systolic blood pressure is the top number when the heart is contracted. Diastolic blood pressure is the bottom number when the heart is relaxed.

Bradycardia: abnormally slow heart rate.

Cardiac Output: the amount of blood pumped by the heart in one minute.

Cardiopulmonary Bypass: a machine that can perform the function of the heart and lung.

Catheter: a small tube used to collect fluid, measure blood pressure or give medication into a blood vessel or other body chamber.

Catheterization: a diagnostic test in which a catheter is inserted into the heart to measure pressure and oxygen, and to take pictures (angiography).

Congestive heart failure: a condition in which the heart cannot pump well enough, and there is backup of blood and congestion in the veins and lungs.

Cyanosis: blueness of the lips and fingernails, caused by a decreased amount of oxygen in the blood.

Diastole: when the heart muscle is relaxed and the ventricles fill with blood.

Heart Rate: how fast the heart is pumping.

Hemodynamics: the study of the flow of blood and the pressures in the heart, usually measured during a catheterization.

Hypertension: high blood pressure.

Hypoxia: less than normal oxygen content in the blood.

Ischemia: lack of blood supply to an organ or tissue.

Leads: the small wires connected to the child's chest by sticky pads which allow measurement of the electrocardiogram.

Mitral Valve: a valve of two leaflets, between the left atrium and left ventricle.

Murmur: an extra heart sound that may be heard between the normal heart sounds. Murmurs may be normal or abnormal. They are caused by increased turbulence of the blood as it moves through the heart, much like water flowing over rocks in a stream.

Myocarditis: an inflammation of the heart muscle, usually caused by a virus or bacteria.

Myocardial Infarction: heart muscle which dies because of lack of oxygen, usually called a heart attack when it occurs in an adult.

Open Heart Surgery: surgery performed on the open heart while the blood flow is diverted through the heart lung machine.

Oxygen: a gas in the air we breath. Sometimes extra is needed due to illness or a heart defect.

Pericarditis: an inflammation of the sac that surrounds the heart.

Pulmonary valve: the valve between the right ventricle and the pulmonary artery.

Septum: dividing wall.

Shunt: an abnormal passage of blood between two blood vessels or between the two sides of the heart.

Stenosis: a narrowing of a heart valve or blood vessel.

Syncope: fainting spell.

Systole: when the heart contracts and pumps the blood into the aorta and pulmonary artery.

Tachycardia: abnormally fast heart rate.

Ventricle: one of the two lower chambers of the heart. The left ventricle pumps to the aorta and supplies blood to the body. The right ventricle pumps to the pulmonary artery and supplies blood to the lungs.

Ventilator: a machine that breathes for a patient or helps his or her breathing.