CHD Definitions

This section contains information about specific heart conditions. Each child can have differing aspects of these conditions so please be aware that not all information may be applicable and for more advice on a specific diagnosis consult your child’s paediatric cardiologist.

Analgesic: A medicine given to stop pain.

Aneurysm: A ballooning of the wall of a vein or an artery or the heart itself due to weakening of the wall by disease, traumatic injury or an abnormality present at birth.

Angiocardiography: A technique for radiographic examination of the heart chambers and thoracic veins and arteries. A liquid radiocontrast agent, typically containing iodine, is injected into the bloodstream, then the tissues are examined using X-rays.

Anomalous Pulmonary Venous Drainage: The pulmonary veins carry red blood from the lungs to the right side of the heart instead of the left side.

Anoxia: Literally, no oxygen. This condition most frequently occurs when the oxygen supply to a part of the body is critically diminished. This may result in the death of the affected tissue.

Antiarrhythmic Drugs: Drugs that are used to treat disorders of the heart rate and rhythm.

Anticoagulant: A medicine such as Warfarin given to stop blood clots forming.

Aorta: Main artery which carries blood from the heart to the body.

Aortic Valve: The valve between the left ventricle and the aorta.

Arrhythmia: Out of rhythm – the heart is beating too fast, too slowly, or irregularly.

Arterial Blood: Blood that picks up oxygen in the lungs and normally passes from the lungs to the left side of the heart via the pulmonary veins. This blood is then pumped by the left side of the heart into the arteries that carry it to all parts of the body.

Artery: Vessel which carries oxygenated blood from the heart to all parts of the body.

Atresia: Blocked or missing.

Atrial Septum: Sometimes called the interatrial septum, this is the muscular wall that divides the left and right upper chambers of the heart, called the atria.

Atrium: An upper chamber of the heart where blood collects before passing to the ventricle.

Bacterial Endocarditis: An inflammation of the inner layer of the heart caused by bacteria, sometimes resulting as a complication of another infectious disease, an operation or injury. The lining of the heart valves is most frequently affected, especially valves with previous damage from rheumatic disease or congenital abnormality.

Balloon septostomy: 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.

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

Bicuspid Valve: Any valve with two cusps (flaps/leaflets). The term may refer to a normal mitral valve or an abnormal aortic or pulmonary valve, which normally has three cusps.

Blood Pressure: The force that flowing blood exerts against the artery walls. Two blood pressures are usually measured: 1)The upper, or systolic, pressure occurs each time the heart contracts to pump blood into the aorta. This part of the heartbeat is called systole; and, 2)The lower, or diastolic, pressure occurs when the heart relaxes and refills with blood. This part of the heartbeat is called diastole. The blood pressure is expressed by two numbers, with the upper one written over the lower one (systolic/diastolic).

Blue Blood: 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.

Bradycardia: Slow heart beat.

BT shunt: Taking blood from an arm artery to the lungs.

Cardiac: Relating to the heart.

Cardiac Arrest: The cessation of the heartbeat. As a result, blood pressure drops abruptly and circulation of blood ceases.

Cardiologist: Doctor specialising in the heart.

Catheter: A narrow tube inserted into a vein or artery and fed to the heart, where it is used to assist in finer diagnosis or repair.

Chest drains: Tubes often left in after heart surgery to drain away fluid

Coarctation of the Aorta: Narrowing in the aorta – the artery taking blood from the heart to the body.

Congenital: Existing at birth.

Congenital Anomaly: An abnormality present at birth.

Congenital Heart Defect: Malformation of the heart or of its major blood vessels present at birth.

Coronary Arteries: The two arteries that arise from the aorta, then arch down over the top of the heart and branch out to provide blood to the working heart muscle.

CPAP: Constant Positive Airway Pressure – this is a way of keeping small airways open, often used before a patient is taken off complete ventilation.

Cyanosed: When there is not enough oxygen in the blood, causing the skin to look blue in some children.

Cyanosis: Blueness of skin caused by insufficient oxygen in the blood. When haemoglobin is not carrying oxygen, it is dark burgundy and is called “reduced haemoglobin.” The blueness of the skin occurs when critical amounts of reduced haemoglobin are present.

Dextra Cardia: The heart is on the right, rather than the left side of the chest.

Digoxin: A drug given to increase the strength, or slow down the rate, of the contraction of the heart.

Dilated cardiomyopathy: A condition in which the heart becomes enlarged and weak, sometimes because of a virus.

Diuretic: Drugs which assist the kidneys to produce and excrete more urine.

Dopple: A 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.

Ductus Arteriosus: A connection outside the heart of the foetus between the pulmonary artery and body of the foetus. Normally this connection closes soon after birth. If it does not close, the condition is known as patent or open ductus arteriosus.

Dysrhythmia (Arrhythmia): An abnormal rhythm of the heart.

Edema: Abnormally large amounts of fluid in the tissues of the body.

ECG: Short for electrocardiogram – for measuring the electrical activity of the heart.

Echo: Short for echocardiogram – an image of the heart created by using high frequency sound waves.

ECMO: A by-pass machine which can be used to support the heart so that it can be rested after surgery, or during a viral illness for example

Endocarditis: An infection of the lining of the heart.

Heart Block: A condition in which the electrical impulse that travels through the heart’s specialised conduction system to trigger the events of the heartbeat is slowed or blocked along its pathway. This can result in a dissociation of the rhythms of the upper and lower heart chambers, and is the major disorder for which artificial pacemakers are used.

Heart Disease: A general term used to mean ailments of the heart or blood vessels related to structure or function. May be present at birth (congenital) or developed after birth (functional).

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 seriously below what is required.

Heart-Lung Machine: A special instrument used to provide circulation to the body during open-heart surgery.

Heart murmur: A murmur is a sound made by blood moving round the heart: sometimes but not always this could be caused by a heart defect.

Heparin: A type of anticoagulant that is given by injection.

Homograft: Putting in human tissue – such as a valve or artery.

Hypertrophic Cardiomyopathy: The heart muscle becomes so thick that it can interfere with its proper function.

Hypoplastic Right Ventricle: The right ventricle has not developed properly so it is small.

ICU (or ITU): Intensive Care Unit – provides a high level of specialist care immediately after surgery.

Mitral Valve: The heart valve between the left atrium and left ventricle. It has two cusps, or flaps.

Open Heart Surgery: Operations performed on the inside of the opened heart.

Pacemaker: A small battery placed under the skin and joined to the heart by pacing wires, which measure the pulse and corrects too fast or too slow rhythms.

PDA: Patent or persistent ductus arteriosus – a passage used for circulation before the baby is born remains open, instead of closing shortly after birth. This causes red blood to return from the aorta back to the lungs.

PICU: Paediatric Intensive Care Unit.

Pericardial effusion: Fluid collects in the pericardial sac – the outer covering of the heart – which can be drawn off using a needle, or drained using diuretics.

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

Pulmonary atresia: Blood cannot be pumped to the lungs from the right ventricle through the pulmonary artery, which is blocked or missing.

Pulmonary hypertension: High pressure of blood moving into the lungs.

Pulmonary stenosis: A narrowing between the right ventricle and the lung artery.

Patent Foramen Ovale: An oval hole, called the foramen ovale, between the left and right upper chambers of the heart, which normally closes shortly after birth, remains open.

Pulmonary: Pertaining to the lungs.

Pulmonary Edema: Congestion of lung tissues often resulting from critical, congenital, or acquired heart or lung disease.

Pulmonary Valve: The heart valve between the right ventricle and pulmonary artery. It has three flaps, or cusps.

Red blood: Blood which has picked up oxygen from the lungs and travel through the left side of the heart to be pumped around the body.

Regurgitation: The abnormal backward flowing of blood through a valve of the heart.

SADS: Sudden Adult/Arrhythmia Death Syndrome.

Sats: Short for saturation levels (of oxygen in the blood).

Septa: The muscular walls dividing the two chambers on the left side of the heart from the two chambers on the right. The atrial septum separates the top chambers and the ventricular septum separates the bottom chambers.

Septostomy: Making a hole in the septum, the wall, between the left and right chambers of the heart.

Shock: Collapse of the circulation related to a congenital heart defect or acquired heart disease or loss of blood volume.

Shunt: A natural or artificially created passageway between two parts of the heart.

Stenosis: A narrowing or stricture of an opening. Mitral stenosis, aortic stenosis, etc., means that the valve indicated has become so narrowed that it does not function normally. Also refers to narrowing of a blood vessel.

Stent: A short, metal mesh tube. Using balloon dilation this is expanded into a narrow artery to hold it open.

Sternum: The breastbone.

Symptomatic: A person is considered symptomatic when he exhibits functional evidence of a disease or condition.

Systolic Blood Pressure: Pressure inside the arteries when the heart contracts with each beat.

Tachycardia: An abnormally rapid heart rate.

TCPC: Total Cavo Pulmonary Connection – a surgical procedure which bypasses the right atrium and pulmonary valve.

Trachea: The Windpipe.

Tracheostomy: A hole cut into the windpipe to help breathing.

Tricuspid atresia: The tricuspid valve is absent.

Tricuspid valve: the valve between the right atrium and right ventricle which has three cusps.

Ultrasound: High frequency sound vibrations, not audible to the human ear. In a sonar-like application, ultrasound can be used by a cardiologist as a diagnostic tool, usually echocardiography.

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

Valve Conduit: An artificial tubing with an artificial valve used in some congenital heart surgeries.

Valvular Insufficiency: Valves that close improperly and permit a backflow of blood. Valvular insufficiency may result from either congenital or acquired heart disease.

Vascular: Pertaining to the blood vessels.

Vein: A vessel carrying blood back to the heart.

Venous Blood: Refers to blood returning to the heart. It is unoxygenated when returning from the body and oxygenated when returning from the lungs.

Ventricle: One of the two main pumping chambers of the heart. The left ventricle pumps oxygenated blood through the arteries to the body. The right ventricle pumps unoxygenated blood through the pulmonary artery to the lungs.