Heart Definitions

When you come to the Heart Institute, you will probably hear words that are not familiar to you. Some commonly used terms are defined in this section.

  • Ablation — a procedure performed in the catheterization (cath) lab in which radiofrequency energy passes through a special catheter to disrupt abnormal electrical pathways inside the heart; it is used to treat arrhythmias
  • Arrhythmia — any change in the normal rate or rhythm of the heartbeat
  • Artery — any large blood vessel that carries blood from the heart to the various parts of the body
  • Atresia — the absence of an opening where one should be located
  • Atria — the two upper chambers of the heart; atrium is the word used to refer to a single chamber
  • Balloon Atrial Septostomy (Rashkind Procedure) — a procedure performed in the cath lab with a special catheter containing a deflated balloon at its tip; the catheter is inserted through a hole in the wall separating the two upper chambers of the heart (atria); when the balloon is inflated and passed through the hole, it usually increases the size of the opening; after this process, the balloon is deflated and the catheter removed
  • Balloon Angioplasty — a procedure performed in the cath lab with a special catheter containing a deflated balloon at its tip; the catheter is inserted into a narrowed blood vessel; when the balloon is carefully inflated, the narrowed area may be stretched open; after this dilation, the balloon is deflated and the catheter removed
  • Balloon Valvuloplasty — a procedure performed in the cath lab with a special catheter containing a deflated balloon at its tip; the catheter is inserted into the opening of a narrowed heart valve; when the balloon is carefully inflated, the valve may be stretched open; after this dilation, the balloon is deflated and the catheter removed
  • Blood Pressure — the pressure of the blood flowing in the arteries
  • Cardiomyopathy — a disease that weakens the heart muscle; it has many different causes
  • Catheter — a long, thin hollow tube that is inserted into a blood vessel during a cardiac catheterization
  • Cyanosis — a blueness of the lips, nail beds and skin; it occurs when there is not enough oxygen in the blood
  • Diastolic Blood Pressure — the bottom number in a blood pressure reading; it is the pressure of the blood in the arteries when the heart muscle is relaxed between each beat
  • Edema — an abnormal amount of fluid in the body tissue; it can result in swelling in various parts of the body, especially the ankles, abdomen, feet or eyelids
  • Endocarditis (Bacterial Endocarditis or BE) — an infection of the inner lining (endocardium) of the heart or heart valves
  • Endocardium — the thin lining which covers the inside of the heart
  • Enlarged Heart — the presence of a heart problem sometimes causes the heart muscle to work very hard; like the body muscles of weight lifters, a heart muscle that is overworked becomes bigger or enlarged
  • Heart Failure — results when the heart cannot effectively pump blood through the body and lungs; inability of the heart to pump well (failure) may cause swelling (edema) to occur in the body or extra fluid to accumulate in the lungs
  • Heart Murmur — an unusual noise made as the blood moves through the heart that can be heard by listening with a stethoscope; there are two kinds of murmurs–one is functional or innocent and is heard in children with normal hearts; the other kind of murmur indicates a structural abnormality, which may or may not be serious
  • Insufficiency — an inadequate functioning of a valve causing regurgitation (leaking or backward flow) of blood through a valve (see Regurgitation)
  • Myocardial Infarction — a heart attack or damage to an area of the heart muscle (myocardium) caused by an interference in blood supply to that area; it is rare in children with heart disease
  • Myocarditis — an inflammation of the heart muscle (myocardium)
  • Myocardium — the muscular part of the heart that pumps blood
  • Occlusion — a procedure performed in the cath lab with a special catheter that allows the placement of various kinds of devices to block patent ductus arteriosus, atrial septal defect or other abnormal connections
  • Pacemaker (Artificial) — a small battery-operated instrument that controls the beating of the heart by sending electrical impulses to the heart muscle; it is used when the heart is beating too slowly; artificial pacemakers may be used temporarily or permanently
  • Pericarditis — an inflammation of the thin, elastic sac around the heart (pericardium)
  • Pericardium — the thin elastic-like sac that covers the outside of the heart
  • Pulmonary Edema — an abnormal amount of fluid that accumulates in the lungs and makes breathing difficult; heart failure may lead to pulmonary edema
  • Pulmonary Hypertension — an abnormally high pressure in the blood vessels of the lungs
  • Regurgitation — the abnormal backward flow of blood through a heart valve caused by a valve that is not functioning adequately (see Insufficiency)
  • Septum — the muscular wall in the middle of the heart that divides the heart into a left side and a right side; the upper part of the septum (atrial septum) separates the right and left atria; the lower part of the septum (ventricular septum) separates the right and left ventricles
  • Stenosis — an abnormal narrowing or tightening of a valve or blood vessel
  • Stent — a device inserted into a blood vessel to make a narrowing larger; the device is implanted with a special catheter during a catheterization procedure
  • Systolic Blood Pressure — the top number in a blood pressure reading; it is the pressure of the blood when the heart muscle contracts with each beat
  • Valves — structures of the heart that act as one-way doors, allowing blood to flow in the proper direction; there are four major valves–mitral, tricuspid, aortic and pulmonary; these structures can be malformed at birth or affected by diseases like rheumatic fever or endocarditis
  • Vein — any blood vessel that carries blood from the body to the heart
  • Ventricles — the two lower chambers of the heart