Health Topic

Arrhythmia

Arrhythmia, also called irregular heartbeat comes in different types. The most common is atrial fibrillation. Read about symptoms and treatment.

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Also called: Irregular heartbeat

Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.

About Arrhythmia

An arrhythmia is a problem with the rate or rhythm of your heartbeat. Your heart beats too quickly, too slowly, or with an irregular pattern. Changes in the electrical signals that control your heartbeat cause arrhythmias.

  • When your heart beats faster than normal, it's called tachycardia.
  • When your heart beats too slowly, it's called bradycardia.
  • When the signal to beat comes too early, it's called a premature or extra heartbeat. It may feel like your heart skipped a beat.

There are many types of arrhythmias. Arrhythmias may affect the upper or lower chamber of your heart. The most common type of arrhythmia is atrial fibrillation, which causes an irregular and fast heartbeat.

Some arrhythmias are harmless, such as when your heart rate speeds up during exercise and slows down when you sleep. But if you have a frequent irregular rhythm, it may mean your heart isn't pumping enough blood into your body. Getting treatment and following a heart-healthy lifestyle can help control arrhythmias. It may also help prevent heart damage that can trigger some heart arrhythmias.

Many factors can affect your heart's rhythm, such as having had a heart attack, smoking, congenital heart defects, and stress. Other factors that could increase your risk for some types of arrhythmias could include if you:

  • Have a family history of arrhythmias.
  • Have certain health conditions, which can include heart and blood vessel diseases, lung diseases, kidney diseases, obesity, and sleep apnea.
  • Are an older adult.
  • Have had recent surgery for your heart, lungs, or throat.
  • Take certain medicines for other health conditions.
  • Use illegal drugs.

If you have risk factors, some situations that make your heart work harder, raise your blood pressure, or cause strong emotional stress may trigger an arrhythmia.

You may not have any noticeable symptoms of an arrhythmia. Your provider may find an arrhythmia during your routine checkup. Symptoms of an arrhythmia can include:

  • Fast or slow heartbeat
  • Skipping, fluttering, or pounding heartbeats
  • Chest pain or discomfort
  • Dizziness or fainting
  • Shortness of breath
  • Sweating
  • Tiredness or weakness

Seek emergency medical care if you have chest pain, shortness of breath, or think you are having a heart attack.

To find out if you have an arrhythmia, your health care provider may order an electrocardiogram (EKG). This test records your heart's electrical activity and is the most common for finding an arrhythmia. Your provider may also:

  • Ask about your medical history, including your symptoms and lifestyle habits.
  • Do a physical exam, which includes checking your heartbeat and pulse.
  • Order blood tests and other heart tests.
  • Check your legs or feet for swelling.
  • Look for signs of other health conditions that could cause an arrythmia, such as thyroid disease.

Treatment may include medicines, an implantable cardioverter-defibrillator (ICD) or pacemaker, or sometimes surgery. Your provider may also recommend avoiding activities that may trigger your arrhythmia.

The goal of treatment is to restore a normal heart rhythm. If not treated, arrhythmias can damage your heart, brain, and other organs and could be life-threatening.

To help prevent an arrhythmia, your provider may suggest that you make heart-healthy lifestyle changes and treat health conditions that may cause arrhythmias.

It sits within Blood, Heart and Circulation.

The lead U.S. institute for this subject is the National Heart, Lung, and Blood Institute.

When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.

Research on Arrhythmia

5,923 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.

What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.

Research currently under way

Research already completed

Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.

Where to read more

Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.

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Diagnosis and Tests

Treatments and Therapies

Prevention and Risk Factors

Related Issues

Genetics

Clinical Trials

Medical subject headings

Clinicians and researchers index this subject under Arrhythmias, Cardiac. These are the terms to use when searching medical literature.

This page is built from the MedlinePlus health topic record for Arrhythmia, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.