An abnormal heart rhythm is when your heart beats too fast, too slow, or irregularly. This is also called an arrhythmia.

Within the heart is a complex system of valves, nodes, and chambers that control how and when the blood is pumped. If the functions of this vital system are disrupted, damaged, or compromised, it can change the pattern with which your heart beats.

Arrhythmias can cause no symptoms, or you may feel discomfort, fluttering, pain, or pounding in your chest.

Not all arrhythmias are life-threatening or cause health complications. But to be on the safe side, you should report any abnormal heart rhythm to your doctor.

The types of abnormal heart rhythms

The most common types of abnormal heart rhythms are:


Tachycardia means that your heart is beating too fast. For example, a normal heart beats 60 to 100 times per minute in adults. Tachycardia is any resting heart rate over 100 beats per minute (BPM).

There are three subtypes of tachycardia:

  • Supraventricular tachycardia occurs in the upper chambers of your heart known as the atria.
  • Ventricular tachycardia occurs in the lower chambers known as the ventricles.
  • Sinus tachycardia is a normal increase in the heart rate that may occur when you’re sick or excited. With sinus tachycardia, your heartbeat returns to normal once you get better or become calm.

Atrial fibrillation

This disorganized heart rhythm occurs in the upper chambers of the heart. It’s the most common arrhythmia.

Atrial fibrillation, or AFib, occurs when many unstable electrical impulses misfire and may result in the atria quivering out of control.

AFib causes the heart rate to increase and become erratic. It can elevate your heart rate to 100 to 200 BPM, which is a lot faster than the normal 60 to 100 BPM.

Atrial flutter

An atrial flutter (AFL) typically occurs in the right atrium, which is one of the two upper chambers of the heart. However, it may occur in the left atrium as well.

The condition is caused by a single electrical impulse that travels rapidly in the affected atrium. This often results in a fast heart rate, but it’s a more regular rhythm.


If you’re bradycardic, it means you have a slow heart rate (less than 60 BPM). Bradycardia generally occurs when the electrical signals traveling from the atria to the ventricles become disrupted.

Some athletes have slower heart rates because they are in excellent physical condition, and this isn’t usually the result of a heart problem.

Ventricular fibrillation

Ventricular fibrillation (VF) can stop the heart from beating and cause cardiac arrest. It occurs in the ventricles, which are unable to pump blood out of your heart to the body and brain due to the irregular heartbeat.

VF is a serious condition that may cause death if it’s not immediately treated.

Premature contractions

With most premature contractions, the heart appears to skip a beat when the pulse is taken in the wrist or chest. The skipped beat is so faint or weak that it’s not heard or felt.

Other types of premature contractions include extra beats and early beats. All three types may occur in the upper or lower heart chambers.

If you have an abnormal heart rhythm, you may experience some or all of these symptoms:

A number of things may cause an abnormal heartbeat, including high blood pressure. Other common causes are:

Coronary heart disease

This serious heart problem occurs when cholesterol and other deposits block the coronary arteries.


Some medications or substances may cause your heart rate to change. These include:

  • caffeine
  • amphetamines, which are drugs that stimulate the brain
  • beta-blockers, which are used to reduce high blood pressure

Other causes

A number of other factors can also cause alterations in your heart’s rhythm. These include:

  • changes in your heart’s muscle after illness or injury
  • healing after heart surgery
  • low potassium and other electrolytes
  • abnormalities of the heart
  • other health conditions

The risks for arrhythmia include:

  • smoking
  • previous heart conditions, or a family history of heart conditions
  • diabetes
  • stress
  • being overweight
  • living a sedentary lifestyle
  • a diet high in fats, cholesterol, and other unhealthy foods
  • high blood pressure or other health problems
  • excessive use of alcohol (more than two drinks per day)
  • drug misuse
  • sleep apnea

Your doctor will perform a physical examination, which will include using a stethoscope to listen to your heart. They may also use an electrocardiogram (EKG or ECG) machine to examine the electrical impulses of your heart. This will help them determine whether your heart rhythm is abnormal and identify the cause.

Other tools that can be used to diagnose an arrhythmia include:

  • Echocardiogram. Also known as a cardiac echo, this test uses sound waves to take pictures of your heart.
  • Holter monitor. You wear this monitor for at least 24 hours while you go about your normal activities. It allows your doctor to track changes in your heart’s rhythm throughout the day.
  • Stress test. For this test, your doctor will make you walk or jog on a treadmill to see how exercise affects your heart.

The Healthline FindCare tool can provide options in your area if you need help finding a cardiologist.

The treatment for an arrhythmia depends on its cause. You may need to make lifestyle changes, like increasing your activity level or changing your diet (for example, limiting your caffeine intake). If you smoke, your doctor will help you stop smoking.

You might also require medication to control your abnormal heartbeat, as well as any secondary symptoms.

For serious abnormalities that don’t go away with behavioral changes or medication, your doctor can recommend:

  • cardiac catheterization to diagnose a heart problem
  • catheter ablation to destroy tissue that causes abnormal rhythms
  • cardioversion by medication or an electrical shock to the heart
  • implantation of a pacemaker or cardioverter defibrillator
  • surgery to correct an abnormality

Although arrhythmia can be quite serious, many cases can be controlled with treatment. Along with treatment, your doctor will want to monitor your condition with regular checkups.

Once your arrhythmia is under control, your doctor will discuss ways to keep it from coming back.

In general, healthy lifestyle choices can go a long way toward helping you control your condition. Your doctor will probably recommend improving your diet, exercising more, and trying to end certain unhealthy behaviors, such as smoking.