Looking after your heart


A treatment to cure or improve symptoms related to fast heart rhythms, involving passage of wires through the blood vessels to enable treatment to be given to an area of electrical abnormality. Ablation usually involves the delivery of radio frequency (RF) energy to heat the tissues of the heart or cryotherapy where the tissues are cooled.

Ambulatory monitoring
Recording of the heart rhythm for 24 hours or longer by a portable ECG recording machine.

Use of drugs that prevent blood clotting. These are used during some cardiac procedures or taken as tablets to prevent stroke in atrial fibrillation.

Abnormal heart rhythm, slow or fast, sometimes irregular, often giving rise to symptom of palpitation.

Cessation of the heart beat.

Top chambers of the heart that receive blood from the body and lungs. The right atrium is where the heart’s natural pacemaker (sino atrial node) can be found.

Atrial fibrillation
Very fast beating of the atria giving rise to a fast and irregular rate of ventricular beating. It is commonly associated with palpitations, breathessness and lethargy. It is associated with an additional risk of stroke if not treated.

AV node
Atrio ventricular node. A critical part of the heart’s electrical conduction system connecting the electrical system in the atria to that in the ventricles.

Slow heart rate.

Cardiac arrest
Cessation of an effective heart beat due to either slowing or ventricular fibrillation/ventricular tachycardia.

Cardiac physiologist
Astaff member skilled in interpreting and providing information on your heart rhythm.

Cardiac resynchronisation therapy (CRT)
The use of an additional pacemaker lead to stimulate the left ventricle so as to improve performance of the heart (biventricular pacing). Used in conjunction with a pacemaker or implantable cardiac defibrillator.

The use of a small energy shock to stop a fast or irregular heart rhythm.

Delivery of an internal or external shock (usually at high energy levels) to restore the heart to normal rhythm from ventricular fibrillation.

Electrocardiogram. The recording of the electrical activity of the heart using 10 electrodes placed on the skin of the arms, legs and chest wall.

An ultrasound scan of the heart that is able to study in detail the muscle and valvular function.

Electrophysiology study
Atest involving recording of electrical signals from inside the heart.

Exercise tolerance test (ETT)
Recording simultaneously the ECG and blood pressure during exercise. This is normally performed on a treadmill or exercise bicycle.

Event monitor
An external recording device to record heart rhythm.

Heart attack
Blockage of a heart artery resulting in death of some or most of the heart muscle, leading to damage to pump action, frequently to abnormal heart rhythms and sometimes to death.

Implantable cardiac defibrillator. An implanted device connected to the heart via leads which are capable of delivering shock treatment internally should the heart go into ventricular tachycardia or ventricular fibrillation. These devices prevent sudden cardiac death.

Implantable loop recorder
An implanted monitor which records heart rhythm continuously for up to 3 years.

An implanted device connected to the heart via pacing leads which control heart rhythm.

A term used to describe a wide range of symptoms, all of which have in common a sensation of abnormality of heart beats (usually a rapid or irregular rhythm)

Remote Patient Monitoring
A new technology allowing physicians to monitor patients with ICDs and pacemakers in the comfort of their own homes. This utilises technologies such as wireless communication and secure internet servers. Heart Rhythm Clinic plans to offer this service to its patients in the very near future.

Sinus node
The area of the right atrium that initiates the heart beat.

Loss of consciousness due to fast or slow rhythms or blood pressure drop.

Sudden cardiac death
Death within 1 hour of the onset of symptoms, frequently caused by abnormal heart rhythm and often associated with heart attacks.

Supraventricular tachycardia (SVT)
Fast heart rhythms involving the atria, often causing palpitations but rarely dangerous.

Tilt table test
A test to investigate reflex control of heart rate and blood pressure.

Vasovagal syndrome
An abnormal reflex causing a drop in heart rate, pressure or both leading to collapse.

The two lower chambers of the heart. These are the main pumping chambers. It is the right ventricle which pumps blood into the lungs and the left ventricle which pumps blood around the body.

Ventricular tachycardia
A fast and usually regular rhythm of the ventricles. Can cause severe symptoms such as syncope or even death. In some situations this can be a benign rhythm.

Ventricular fibrillation
An extremely fast and iirregular rhythm of the ventricles. Without prompt treatment this will lead to sudden cardiac death.

Wolff Parkinson White (WPW) syndrome
A particular form of supraventricular tachycardia, often associated with palpitation but a rare cause of sudden cardiac death.

If you feel that other terms should be included in this glossary then please let the Heart Rhythm Clinic know at info@heartrhythmclinic.com


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Heart Rhythm Clinic is based at Spire Southampton Hospital but also consults in Lymington, Sarum Road (Winchester) and the Nuffield Hospital, Southampton.