Medical Terms Explained

Analgesic

Any medicine given to stop pain.

Amniocentesis

A test carried out during pregnancy which takes a sample of amniotic fluid which can be tested to check for Down's Syndrome.

Angiocardiogram

An X-ray of the heart assisted by a liquid introduced through a catheter.

Anticoagulant

A drug whose purpose is to reduce blood clotting (see Drugs Topic Note).

Aorta

Main artery of the heart which carries blood to the body.

Aortic Stenosis

A narrowing that restricts the flow of the oxygen rich blood from the left ventricle to the aorta.

Aortic valve

The valve between the left ventricle (pumping chamber) and the aorta.

Arrhythmia

Disturbance of normal rhythm of the heart.

Artery

Blood vessel which carries blood from the heart to all parts of the body and lungs.

ASD (Atrial Septal Defect)

A hole in the septum (central heart wall) between the two atria (collecting chambers) allowing blood to flow from the left to the right side of the heart (see ASD Topic Note).

Aspirin

A drug used to prevent blood clots.

Atresia

Connection that is either blocked or missing altogether.

Atria

The collecting chambers of the heart - plural of atrium.

Atrial Septal Defect (ASD)

A hole in the septum (central heart wall) between the two atria (collecting chambers) allowing blood to flow from the left to the right side of the heart (see ASD Topic Note).

Atrial septostomy

Where a hole is deliberately made between the atria.

Atrio Ventricular Septal Defect (AVSD)

A hole in the septum (central heart wall) between the atria and between the ventricles with often a common valve between all four chambers. The most common heart defect in babies with Down's Syndrome (see AVSD Topic Note).

Atrium

An upper collecting chamber in the heart which receives incoming blood.

AV Canal Defect

Another name for Atrio Ventricular Septal Defect.

AVSD (Atrio Ventricular Septal Defect)

A hole in the septum (central heart wall) between the atria and between the ventricles with often a common valve between all four chambers. The most common heart defect in babies with Down's Syndrome (see AVSD Topic Note).

Banding

Narrowing of the pulmonary artery with a band to reduce blood flow to the lungs.

Bicuspid

Describes a valve which has two cusps (the flaps which should close it.)

Biopsy

A small piece of body tissue taken for examination.

Blue Baby

A baby who has too little oxygenated blood circulating and therefore has a blue tinge to certain parts of the skin (see cyanosis).

Bradycardia

Abnormally slow heart rate.

Bypass

When a machine is used to oxygenate and circulate the blood allowing them to bypass the lungs and heart during surgery.

Cannula

A fine tube inserted into a vein allowing drugs to be given.

Cardiac

Relating to the heart.

Cardiac Liaison Sister

A senior nurse in cardiac units to assist families with queries or problems (see Heart Team Topic Note).

Cardiac Surgeon

A surgeon who specialises in the heart (see Heart Team Topic Note).

Cardiologist

A physician specialising in the heart (see Heart Team Topic Note).

Cardiopulmonary Bypass

A machine which takes over the heart and lung functions during surgery.

Catheter

A narrow tube inserted into a vein or artery and fed to the heart, where it is used to carry out repair or to refine diagnosis (see Catheterisation Topic Note).

Chest Drains

These are tubes left in after heart surgery to drain away excess fluid.

Chylothorax

A fatty fluid which can leak into the chest as a result of the trauma of heart surgery.

Coarctation

A narrowing in a blood vessel.

Congenital

Existing at birth.

Congestion

An excess of fluid in part of the body i.e. the lungs.

CPAP (Continuous Positive Airway Pressure)

This is a way of keeping small airways open, often used before a patient is taken off complete ventilation.

Cyanosis

Blueness of the skin caused by insufficient oxygen in the blood.

Digoxin

A drug which increases the contraction of the heart muscle (see Drugs Topic Note).

Diuretics

Drugs which assist the kidneys to produce and excrete more urine
(see Drugs Topic Note).

Doppler

An echocardiogram test using sound waves to measure the speed and direction of blood flow in the heart.

Drain

A tube to remove fluid from the body.

Duct

A tube in the body which conducts blood.

Echocardiogram

A technique using high frequency sound waves on a screen to produce a picture of the heart and surrounding blood vessels.

ECMO

A bypass machine similar to the heart lung machine which is sometimes used to support the heart and give it a rest after surgery.

Electrocardiogram

A technique which records the electric currents produced by the heart.

Endocarditis

An infection of the heart lining or the heart valves.

Fallot's

See Tetralogy of Fallot.

Heart Failure

Inability of the heart to maintain adequate blood circulation.  It does not mean that the heart has ceased to function, but that it is operating inefficiently.

Heart Lung Machine

A machine through which the bloodstream is diverted which is used to oxygenate blood and pump it round the body during open heart operations.

HDU (High Dependency Unit)

Sometimes after leaving the Intensive Care Unit, a higher level of care is needed than that on the normal ward, so patients are transferred to the High Dependency Unit.

Heart Murmur

The sound made by blood flowing through the heart.

ICU / ITU (Intensive Care Unit)

Provides a high level of specialist care especially immediately after surgery (see Intensive Care Topic Note). See also PICU for babies and children.

INR test

This is a blood test used to check how fast the blood is clotting and adjust the level of anticoagulants prescribed.

Mitral Valve

Valve between the left atrium and left ventricle.

Murmur

The noise produced by blood flow within the heart which can indicate a heart defect.

Naso gastric or NG tube

A tube used for feeding directly into the stomach.  It goes into the nose and then down the throat.

Oedema

A build up of excess fluid accumulating in body tissue.

Open Heart Surgery

Operations performed on the inside of the opened heart.

Pacemaker

A device which controls the rhythm of the heart if it becomes unsettled.

Pacing Wires

Wires which are used to connect a pacemaker to the heart.

Paediatrics

The branch of medicine dealing with the diseases of children.

PDA (Persistent Ductus Arteriosus)

A congenital condition where the duct between the aorta and the pulmonary artery sides of the heart fails to close after birth, as it should do, and allows blood to flow between the two sides of the heart (see PDA Topic Note).

Pericardium

The sac or bag surrounding the heart.

PICU (Paediatric Intensive Care Unit)

Provides a high level of specialist care especially immediately after surgery (see Intensive Care Topic Note).

Polycythaemia

A condition where there are an increased number of red cells within the blood.

Prognosis

The estimated outcome of the particular problem a patient has.

Prophylactic

A preventative medicine given to protect against the possibility of infection.

Pulmonary

Relating to the lungs.

Pulmonary Artery

The large artery which conveys deoxygenated blood from the heart to the lungs.

Pulmonary Hypertension

Elevated pressure of blood flowing into the lungs, often caused by the left to right shunting through a septal defect.

Pulmonary Valve

The valve between the right ventricle and the pulmonary artery.

Sats

Common abbreviation for saturation levels referring to the percentage of oxygen found in the blood (see Non Invasive Tests Topic Note).

Septostomy

The process of making a hole in the septum (heart wall).

Septum

The tissue wall in the heart which divides the chambers on the left side from the chambers on the right side and thus separates the oxygenated from the deoxygenated blood, with their different blood pressures (see Pulmonary Hypertension Topic Note).

Shunt

A natural or surgically inserted connection between the two sides of the heart.

Stenosis

A narrowing of a vessel.

Sternum

The breastbone.

Tachycardia

An abnormally rapid heart rate.

Tetralogy of Fallot

A congenital malformation of the heart involving four defects (see Fallot's Tetralogy Topic Note).

Transoesophageal echocardiogram

An echocardiogram performed by passing the transducer down the throat into the oesophagus (see Non Invasive Tests Topic Note).

Tricuspid Valve

Valve, consisting of three cusps, or triangular segments, between the right atrium and the right ventricle.

Valve

A structure which opens and closes. When open it allows blood flow in one direction and when closed prevents back flow or leakage.

Vascular

Pertaining to blood vessels.

Vasodilators

Drugs which increase the size of the blood vessels and thus reduce blood pressure (see Drugs Topic Note).

Vein

A vessel carrying blood back to the heart.

Ventricle

The lower chambers of the heart which act as the pump for the blood's circulation.

VSD (Ventricular Septal Defect)

A hole in the septum (central heart wall) between the two ventricles (pumping chambers) which allows blood to flow between the two sides of the heart (see VSD Topic Note).