Cardiac Electrical System
Heart Rhythm Disorders
Heart rhythm disorders, also called arrhythmias, can involve the heart rate, how regular the rhythm is, how electrical impulses are formed, or how they travel through the heart. This page helps you find the right information.
On this page
The basics
Understanding Heart Rhythm
A normal heartbeat starts with an electrical impulse in the sinus node in the upper right chamber. The impulse spreads through the upper chambers, passes through the atrioventricular node and then travels along specialised pathways to the lower chambers, which contract to pump blood.
In an arrhythmia, part of this process changes. The rhythm may be too fast, too slow or irregular. An impulse may start in an unusual place, follow an extra pathway, or be delayed or blocked on its way. Some arrhythmias are harmless, while others need assessment and treatment.
Some rhythm disorders tend to appear at particular stages of life. For example, atrial fibrillation becomes more common with advancing age, while re-entrant tachycardias such as SVT often begin in younger people. These are general tendencies only and not diagnostic rules; symptoms at any age deserve proper assessment.
Find your topic
Main Groups of Rhythm Disorders
Rhythm disorders are often grouped by where they arise and how they behave. Each group below leads to the detailed pages.
Atrial rhythm disorders
Arise in the upper chambers of the heart.
An irregular and often fast rhythm from the upper chambers.
A more organised, usually fast rhythm in the upper chambers.
Supraventricular tachycardias
Fast rhythms that involve the upper chambers or the AV node, including re-entry circuits such as AVNRT, which is mentioned within the SVT page.
Episodes of rapid heartbeat that start above the lower chambers.
A re-entry circuit in or near the AV node that causes a sudden, rapid and regular heartbeat.
A condition with an extra electrical pathway between the upper and lower chambers.
Ventricular rhythm disorders
Arise in the lower chambers of the heart.
Extra beats that start in the lower chambers.
A fast rhythm that starts in the lower chambers.
A wider overview of rhythm problems from the lower chambers.
A life-threatening ventricular rhythm that needs emergency treatment.
Slow rhythms and conduction disorders
The heart rate is slow or electrical signals are delayed or blocked.
Slow heart rhythms and problems with electrical conduction.
Inherited rhythm disorders
Conditions that run in families, including Brugada syndrome, which is described within the inherited syndromes page.
An overview of inherited electrical conditions of the heart.
An inherited electrical condition associated with a characteristic ECG pattern.
Symptoms and related conditions
Common presentations and related findings that often prompt a rhythm assessment.
An overview of inherited electrical conditions of the heart.
An overview of inherited electrical conditions of the heart.
An overview of inherited electrical conditions of the heart.
Possible presentation
Symptoms That May Be Related
People with rhythm problems may notice different things, and some notice nothing at all. Symptoms that may be related include:
Rhythm
Heartbeat sensations
Palpitations, skipped beats, a rapid heartbeat or a slow heartbeat.
Circulation
Dizziness or fainting
Light-headedness, near-fainting or fainting.
Effort
Exercise and breathing
Reduced exercise tolerance or shortness of breath.
Energy
Fatigue
Unusual tiredness or weakness, particularly when it comes with a slow, fast or irregular pulse.
Pulse
Irregular or rapid pulse
A pulse that feels irregular, unusually fast or unusually slow, at the wrist or neck or on a home device.
Warning signs
Symptoms that need urgent help
Fainting, chest pain or severe breathlessness need urgent medical care and should not wait for a routine appointment.
These symptoms have many possible causes, and having one of them does not mean that you have an arrhythmia. A doctor can help to work out the reason. Seek urgent medical help for fainting, chest pain or severe breathlessness.
Age and context
Age and Clinical Context
Rhythm disorders can occur at any age, but the pattern differs. Younger people more often present with regular, sudden-onset fast rhythms such as SVT or conditions involving an extra electrical pathway. Atrial fibrillation becomes more common with increasing age, as do slow rhythms and conduction problems.
Children and athletes may need different clinical context. Normal heart rates and rhythm variations differ with age and with training, so findings are interpreted accordingly, sometimes with paediatric expertise. Treatment is never chosen by age alone. See Other Heart Rhythm Disorders.
Diagnosis
How Rhythm Disorders Are Assessed
Assessment starts with your symptoms and history and then uses tests to record the heart’s rhythm. Which tests are used depends on how often symptoms occur and what question needs to be answered.
Overview
Treatment Overview
Treatment depends on the type of rhythm disorder, the symptoms and the individual situation. Some people need monitoring only, and others are offered medicines, a procedure or a device. These pages explain the options.
Procedures
Catheter-based treatment
Catheter ablation and AF ablation, with different energy technologies.
Rhythm restoration
Cardioversion
A planned procedure to restore a normal rhythm in selected patients.
Devices
Pacemaker and ICD
Implanted devices for slow rhythms or dangerous fast rhythms.
- Catheter Ablation
- Atrial Fibrillation Ablation
- Radiofrequency Ablation
- Cryoablation
- Pulsed Field Ablation
- Electrical Cardioversion
- Pacemaker
- Implantable Cardioverter-Defibrillator (ICD)
- Atrial Flutter Ablation
- SVT Ablation
- PVC Ablation
- VT Ablation
- Epicardial Ablation
- Cardioneuroablation
- Left Atrial Appendage Closure
- All treatments
Questions
Frequently Asked Questions
What is a heart rhythm disorder?
A condition in which the heart beats too fast, too slow or irregularly, or in which electrical signals do not travel normally.
Are all arrhythmias dangerous?
No. Some are harmless and others need treatment. Assessment helps to tell them apart.
Do palpitations always mean an arrhythmia?
No. Palpitations have many causes. A doctor can help to find out whether the rhythm is involved.
Which test will I need?
This depends on your symptoms and how often they occur. The diagnostics page explains the main options.
Can rhythm disorders run in families?
Some can. These are described under inherited arrhythmia syndromes.
Do all rhythm disorders need a procedure?
No. Treatment depends on the type of rhythm problem, symptoms and individual factors.
When should I seek urgent help?
For fainting, chest pain, severe breathlessness or any sudden serious symptom, seek emergency medical help.
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