Arrhythmia (Irregular Heartbeat) | Heart and Vascular


What Is Arrhythmia?

Arrhythmia is a condition in which your heartbeat may be too fast (tachycardia), too slow (bradycardia), or irregular. Physicians may also refer to this condition as heart arrhythmia, cardiac arrhythmia or dysrhythmia.

If your heart doesn't beat properly, blood can't travel effectively to your lungs, brain or other organs. Without proper blood flow, your organs may become damaged or stop working.

Severity of arrhythmia can vary from no symptoms to stroke or cardiac arrest. This is based on the source of arrhythmia, the cause as well as the type of arrhythmia.  


Symptoms of Arrhythmia

Arrhythmia symptoms can range from unnoticeable to severe pain, heart attack and stroke. If you have heart disease, your symptoms may be more noticeable and could get worse.

Your health care provider may also notice an irregular heartbeat during your examination for another health reason. The most common arrhythmia symptoms include extreme tiredness, dizziness or fluttering in the chest.

Common Symptoms

It’s important to talk to your physician if you experience any arrhythmia symptoms, which can include:

  • Alternating fast (tachycardia) and slow (bradycardia) heartbeat
  • Dizziness or feeling lightheaded
  • Fainting or near-fainting
  • Fluttering sensation in the chest
  • Sweating
  • Tiredness or weakness

Emergency Symptoms

Heart fluttering and skipped or extra heartbeats (palpitations) are signs of arrhythmia or something more serious. In some cases, arrhythmia can be dangerous and require fast medical attention.

Call 911 immediately if you experience chest pain or heart attack symptoms, such as:

  • Chest pain, pressure
  • Cold sweat, nausea or lightheadedness
  • Collapse and sudden cardiac arrest
  • Discomfort in the upper body, including both arms, the back, stomach, neck and jaw
  • Heart palpitations
  • Shortness of breath

Causes of Arrhythmia

Arrhythmia, or an irregular heartbeat, can happen for many reasons. Heart rhythm problems often result when the electrical signals that direct your heartbeat don't work properly.

Heart Disease

Heart diseases are the most common cause of severe arrhythmias. Possible contributing conditions include:

  • Congenital heart disease
  • Abnormal heart valve function
  • Heart failure
  • Cardiomyopathy
  • Coronary artery disease
  • Inflammation and infiltrative diseases
High Blood Pressure

High blood pressure can force your heart to work harder to pump blood through your arteries and veins. This extra effort could throw off your heart’s natural rhythm.


Heightened emotions like anger and anxiety can throw your heart’s electrical signals off, causing minor arrhythmia.

Substance Use

Caffeine, alcohol, methamphetamine, cocaine and marijuana can all affect the heart in different ways.


Many medications can speed up or slow down your heart rate as a side effect.


Arrhythmia Risk Factors

Changes in heartbeat are normal and expected during sleep, physical activity and moments of stress.

However, you should talk to your physician if you experience irregular heartbeat, as it may be a serious problem. Untreated arrhythmias could result in cardiac arrest and stroke.

Risk factors for arrhythmia include:

Advanced Age

As you get older, your heart and other organs may not work as well as they once did. With normal aging comes general wear on your body.


Low blood sugar levels can throw your heart off its rhythm.


Obesity can increase your blood pressure and heart output without necessarily changing your heart rate. Changes in blood flow can stretch the walls of your heart chambers, affecting how well they pump.

Sleep Apnea

Sleep apnea is a sleep disorder in which your breathing stops and starts throughout the night. Halted breathing can disrupt your heart rate.


Diagnosis of Arrhythmia

Expect your physician to do a physical exam and ask questions about your medical history and symptoms. Keep track of when and how often your symptoms occur, and bring that information to your appointment. Your observations can help your physician diagnose and treat arrhythmia.

There are several types of arrhythmias. They can range from a minor to severe risk to your health.

Your physician may order common tests to confirm an irregular heartbeat and any conditions that can cause arrhythmias.

These tests may include: 

  • Ambulatory monitors (Holter monitor) that record your heart’s activity over a period of time  
  • Blood tests to check your electrolyte levels or look for genetic issues 
  • Cardiac catheterization, a procedure where physicians place a tube called a catheter in your coronary arteries to understand how your heart is working.  
  • Tilt table test may be used if you’ve had fainting spells. It safely tests your body’s reaction to moving from lying to standing.  
  • Stress tests that are medically supervised exercise tests performed on a treadmill or stationary bike. If your physician suspects physical exertion is triggering your arrhythmia, they may recommend this test.  

 Your physician may also recommend imaging tests, such as: 

  • Computed tomography (CT) scan to assess the size and function of your heart and heart valves. CT scans use X-rays to produce images of your chest. 
  • Echocardiogram that uses sound waves to create pictures of your heart’s size, structure, and motion 
  • Electrocardiogram (ECG or EKG) to detect your heart’s electrical activity and measure the time and duration  
  • Electrophysiology testing (EP study) which reveals the electrical activity in your heart through electrodes placed in the heart’s blood vessels.  
  • Magnetic resonance imaging (MRI) that uses magnets and radio waves to create images of your heart 

Treatments for Arrhythmia

Arrhythmia is a common condition that is treated with lifestyle changes, medicines, therapies, and surgery to help prevent blood clots and restore your heart’s normal rhythm.

Your physician will recommend treatments based on the type and severity of your arrhythmia and can include: 


There are several medications available that restore your heart’s normal rhythm by slowing your heart rate. There are others that physicians use to prevent blood clots from forming.

Your physician may recommend: 

  • Beta blockers
  • Blood thinners
  • Calcium channel blockers
  • Other heart rhythm medications

Lifestyle Changes and Therapies

Adopting heart-healthy lifestyle changes is the most common way to prevent arrhythmia and reduce your risk of more severe health complications.

These changes include: 

  • Controlling cholesterol levels 
  • Controlling blood pressure 
  • Eating a heart healthy diet 
  • Exercising regularly 
  • Limiting or avoiding alcohol consumption 
  • Avoiding drugs of abuse 
  • Losing excess weight 
  • Managing stress 
  • Quitting smoking or other tobacco use 

Check out our classes to learn more about heart health


In addition to medication and lifestyle changes, your physician may also recommend therapies to correct your irregular heartbeat.

These therapies include: 

  • Cardioversion 
  • Catheter ablation 
  • Implantable devices such as pacemakers or defibrillators 


If medications, therapies and lifestyle changes are not effective, your physician may recommend surgery to treatment the arrhythmia. Some surgeries involve the use of a narrow tube (catheter) to implant a device that will restore the rhythm of your heart. Other procedures may require open-heart surgery.

Arrhythmia surgeries include: 

  • Catheter ablation
  • Implantable cardioverter defibrillator
  • Maze procedure
  • Pacemaker implant

How common is arrhythmia?

12.1MPeople in the U.S. expected to be diagnosed with atrial fibrillation (AFib)

Source: Centers for Disease Control and Prevention: Atrial Fibrillation

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