What Is A Heart Arrhythmia?

Heart rhythm problems (heart arrhythmias) occur when the electrical impulses in your heart that coordinate your heartbeats do not work properly, causing your heart to beat too fast, too slow or irregularly.

Heart arrhythmias may feel like a fluttering or racing heart, and they're often harmless. However, some heart arrhythmias may cause bothersome - sometimes even life-threatening - signs and symptoms.

Types of Arrhythmias

Atrial Fibrillation (A-Fib)

Atrial fibrillation is an irregular and often rapid heart rate that commonly causes poor blood flow to the body. During atrial fibrillation, the heart's two upper chambers (the atria) beat chaotically and irregularly - out of coordination with the two lower chambers (the ventricles) of the heart.

Tachycardia (Fast Heart Rhythms)

Tachycardia is a very fast heart rate of more than 100 beats per minute. The many forms of tachycardia depend on where the fast heart rate begins. If it begins in the ventricles, it is called ventricular tachycardia. If it begins above the ventricles, it is called supraventricular tachycardia. Types of supraventricular arrhythmias include atrial fibrillation (AF), atrial flutter, paroxysmal supraventricular tachycardia (PSVT), and Wolff-Parkinson-White (WPW) syndrome.

Bradyarrhythmias (Slow Heart Rhythms)

Bradycardia is a very slow heart rate of less than 60 beats per minute. It happens when the electrical impulse that signals the heart to contract is not formed in your heart's natural pacemaker, the sinoatrial node (SA node), or is not sent to the heart's lower chambers (the ventricles) through the proper channels.

Premature Contraction

Premature contractions are the most common type of arrhythmia and they typically do not cause any symptoms. When there are symptoms, they can feel like fluttering in the chest. Premature beats most often occur naturally and are not due to heart disease; however certain heart diseases can cause premature beats.


Arrhythmias may not have any signs or symptoms. Your doctor might find you have an arrhythmia before you do, during a routine examination. Noticeable arrhythmia symptoms may include:

  • Fluttering in your chest
  • Racing heartbeat (tachycardia)
  • Slow heartbeat (bradycardia)
  • Chest pain
  • Shortness of breath
  • Lightheadedness
  • Dizziness
  • Fainting

Causes and Risk Factors

Many things can lead to, or cause, an arrhythmia, including:

  • A heart attack
  • Scarring of heart tissue
  • Changes of heart structure, such as cardiomyopathy
  • Blocked arteries, coronary artery disease
  • High blood pressure
  • Diabetes
  • Overactive thyroid gland
  • Smoking
  • Drinking to much caffeine or alcohol
  • Drug use
  • Stress
  • Medication
  • Dietary supplements
  • Electric shock
  • Air pollution


To diagnose a heart arrhythmia, your doctor may ask about - or test for - conditions that may trigger your arrhythmia, such as heart disease or a problem with your thyroid gland. Your doctor may also perform heart-monitoring tests specific to arrhythmias. These may include:


If you have an arrhythmia, treatment may or may not be necessary. Usually it's required only if the arrhythmia is causing significant symptoms or if it's putting you at risk of a more serious arrhythmia or arrhythmia complication. Treatments may include:

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Gina Simpson, Heart Disease