What Is Arrhythmia?

An arrhythmia is any kind of irregular heartbeat. If you have an arrhythmia, your heart might beat too fast, too slow or in an erratic pattern.

For many people, arrhythmias are harmless. Sometimes, though, an arrhythmia makes the heart unable to pump blood effectively. The condition may prevent enough blood and oxygen from reaching the brain, heart and other organs – and can cause serious, life-threatening conditions.

The good news is that we can successfully treat even serious arrhythmias. In fact, Aurora Health Care is Wisconsin’s leader in understanding and correcting abnormal heart rhythms. That means that with treatment, chances are excellent that you’ll live an active, healthy life.


Types of Arrhythmias

After a complete medical examination, we will identify your specific type of arrhythmia and its causes. Then, we’ll develop a personalized treatment plan to control your heartbeat.

Understanding Types of Arrhythmias

Doctors describe arrhythmias by their speed and location in the heart. Arrhythmias prevent enough blood from reaching your brain and other parts of the body. Without enough blood flow to the brain, you can become confused, dizzy, disoriented and even pass out.

  • Ventricular arrhythmias happen in the ventricles (lower heart chambers).
  • Supraventricular arrhythmias happen above the ventricles – usually in the atria (upper heart chambers).
  • Tachycardia means the heart beats very fast – usually 100 beats per minute or more. Tachycardia accounts for many cases of arrhythmia.
  • Bradycardia, also called bradyarrhythmia, means your heart is beating very slowly – usually less than 60 beats per minute.

Ventricular Arrhythmias

Ventricular arrhythmias are irregular heartbeats that start in the ventricles. Some ventricular arrhythmias are very dangerous and can cause sudden cardiac arrest (SCA) or sudden cardiac death (SCD).

Types of ventricular arrhythmias include:

  • Premature ventricular contractions (PVCs): These irregular heartbeats that occur in the ventricles are the most common type of arrhythmia and are usually harmless.
  • Ventricular fibrillation (VF or V-Fib): The ventricles quiver in a fast, irregular pattern instead of pumping steadily.
  • Ventricular tachycardia (VT or V-tach): In older adults and people with heart conditions, this rapid, regular heartbeat can be dangerous. It can lead to fainting (syncope), ventricular fibrillation and SCD.

Supraventricular Arrhythmias

Supraventricular arrhythmias are tachycardias, rapid heartbeats that begin in the atria. The types include:

  • Atrial fibrillation: A rapid, irregular heartbeat is called atrial fibrillation.
  • Atrial flutter: Atrial flutter is a rapid, but regular, heartbeat.
  • AV nodal reentrant tachycardia (AVNRT): AVNRT is a common SVT that begins in the AV node – a group of cells located between the atria and ventricles.
  • Wolff-Parkinson-White syndrome: A type of congenital heart disease, Wolff-Parkinson-White syndrome is a rare tachycardia involving an extra electrical pathway in the heart.
  • Premature atrial contractions (PACs): A common type of irregular heartbeat that occurs in the atria is known as PACs.


Symptoms of Arrhythmia

The fluttering or pounding sensation of an irregular heartbeat can be stressful. Everybody feels an abnormal heart rhythm once in a while. But if it happens often or for no apparent reason, it could be a sign of arrhythmia.

If you experience any of the following symptoms, you should call your doctor or 911:

  • A fast heartbeat (tachycardia)
  • A slow heartbeat (bradycardia)
  • Heart palpitations (heart skipping a beat or beating too hard or fast)
  • Chest pain
  • Shortness of breath
  • Sweating
  • Weakness, dizziness and light-headedness
  • Loss of consciousness, blackouts or fainting (syncope)

Causes & Complications

Arrhythmia: Causes and Complications

An arrhythmia happens because of a problem with the heart's electrical system.

  • When the heart is pumping correctly, tiny electrical currents signal the heart to beat.
  • With arrhythmia, the heart may have extra signals, missing signals or slow signals. Or the signals might not travel normally through the heart.

Causes of arrhythmia include:

Causes of ventricular arrhythmia include:

  • Abnormally low levels of electrolytes, such as sodium, calcium or potassium
  • Accidental electrical shocks
  • Coronary artery disease

If arrhythmia isn’t treated, it can create health problems over time, such as:

  • Blood clots: An abnormal heart rhythm can prevent proper blood flow through the heart, causing blood to back up. Blood clots can form, which raises the risk of having a stroke.
  • Heart failure: AFib can weaken the heart’s chambers and result in heart failure and other conditions.


Diagnosing Arrhythmia

Sometimes, people feel arrhythmia as a fluttering sensation in the chest. Other times, your doctor might detect an arrhythmia in test results or when listening to your heartbeat.

To confirm an arrhythmia diagnosis, we will perform a physical exam. We may order additional tests, if necessary, including:

  • Laboratory testing: Blood work and other laboratory testing can detect abnormal electrolyte or thyroid hormone levels, signs of arrhythmia.
  • Heart function tests: Several tests can help doctors check the function of your heart. These may include:
  • Portable monitoring: Holter monitoring uses a portable EKG that continuously monitors your heart for 24 to 48 hours. Event monitoring records heart rhythms when symptoms occur, over about a month.
  • Stress test: Sometimes, we test people while they exercise so doctors can see how their heart functions when it is working hard. If you are unable to exercise, we can give you medication to simulate exercise during the stress test.
  • Minimally invasive procedures: We insert catheters, thin tubes with a tiny camera, through a blood vessel to examine the arteries and heart. Sometimes, we add dye to a cardiac catheterization to review the blood flow through your heart. This test is called coronary angiography.
  • Nuclear heart scan: Doctors may use nuclear cardiology imaging tests, including a positron emission tomography (PET) scan, which uses a safe dose of radioactive material to evaluate blood flow through the heart.

Learn more about heart and vascular diagnosis and testing at Aurora.


Individualized Arrhythmia Care

Treating underlying conditions is often an important first step in arrhythmia management.

Your doctor may prescribe medications to help regulate your heartbeat. We also may recommend treatment such as:

  • Cardiac ablation: In this procedure, we thread catheters through a blood vessel to your heart. Energy travels through the catheters to treat the tissue that is causing the arrhythmia. Learn more about cardiac ablation.
  • Electrical cardioversion: This quick procedure, performed under anesthesia, uses a mild electric shock to return the heartbeat to a normal rhythm. People usually go home an hour or two after the procedure. Find out more about electrical cardioversion.
  • Implantable defibrillator: In some cases, we may recommend an implantable cardioverter defibrillator (ICD). This device detects an arrhythmia and sends a mild electric shock to correct the heart’s rhythm. Read more about a ICDs.
  • Pacemaker: A pacemaker is a small device that we can implant in your chest to keep your heart beating regularly – not too fast or too slow. Find out more about a pacemaker implant.
  • Surgery: Our surgeons are skilled experts in a minimally invasive hybrid ablation procedure for people with arrhythmia. This procedure corrects heart rhythm almost painlessly and more effectively than many medications.

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