Heart Rhythm Disorders

Millions of people experience irregular or abnormal heartbeats, called arrhythmias, at some point in their lives. Most of the time, they are harmless and happen in healthy people free of heart disease. However, some abnormal heart rhythms can be serious or even deadly. Having other types of heart disease can also increase the risk of arrhythmias.

Heart rhythm disorders can be divided into three broad categories, electrical, circulatory, and structural. Cardiologists are physicians who diagnose and treat disorders of the heart. Electrophysiology is a subspecialty branch of cardiology. An electrophysiologist (EP) is highly trained in the management of electrical properties of the heart, and is the most knowledgeable doctor to deal with the many often complex options for treating heart beat, or heart rhythm, disorders.

Electrical

Abnormal heart rhythms (arrhythmias) are caused by problems with the electrical system that regulates the steady heartbeat. The heart rate may be too slow or too fast; it may stay steady or become chaotic (irregular and disorganized). Some arrhythmias are very dangerous and cause sudden cardiac death, while others may be bothersome but not life threatening.

Learn More
Circulatory

High Blood Pressure and coronary artery disease (causing blockages in the pipes (arteries) that supply blood to the heart) are the main causes of blood vessel disorders. They can result in a stroke or heart attack, which can be devastating. Fortunately, there are many preventative and treatment options.

Learn More
Structural

Heart muscle disease (cardiomyopathy) and congenital abnormalities (problems in the development of the heart and blood vessels which are present from birth) are two problems that can damage the heart muscle or valves.

Learn More
Pediatrics and Congenital Heart Disease

This section is for pediatric patients and families living with heart rhythm disorders and heart rhythm disorders related to congenital heart disease (CHD).

Learn More
Last updated on January 12, 2021
Sort results
Sort results
16 total results
More Questions?

Take this information with you to a physician that specializes in heart rhythm disorders by using our international specialist directory.

Find a Specialist
Assess Your AFib Risk

Atrial fibrillation (AFib) is the most common abnormal heart rhythm. In a normal heart, the four chambers of the heart beat in a steady, rhythmic pattern. With AFib, the atria (upper chambers of the heart) fibrillate (quiver or twitch quickly) and create an irregular rhythm.

Learn Your Risk for AFib
Atrial Fibrillation (AFib)
Have you or your loved one been diagnosed with atrial fibrillation (AFib)? You should know that you are not alone — many people worldwide have AFib, the most common heart rhythm disorder.
Learn More About Atrial Fibrillation (AFib)
Atrial Flutter (AFL)
Atrial flutter is similar to AFib because it also occurs in the atria or upper chambers of the heart and can result in a fast heartbeat. However, AFL tends to be an organized rhythm that is caused by an electrical wave that circulates very rapidly in the atrium, about 300 times a minute. This can lead to a very fast, but regular, heartbeat. Like AFib, the atria are not able to beat well and this results in an increased risk of a stroke.
Learn More About Atrial Flutter (AFL)
Cardiomyopathy (CM) in Adults
Cardiomyopathy refers to conditions that affect the myocardium (heart muscle). CM can cause your heart muscles to become stiff, enlarged, thick, and/or scarred, making it harder for the heart to pump blood to the rest of the body. The most common complication of CM is heart failure.
Learn More About Cardiomyopathy (CM) in Adults
Heart Attack (Myocardial Infarction)
When arteries become so clogged that the flow of blood to the heart is reduced or stopped, the lack of oxygen can damage or kill the heart muscle, causing a heart attack. Knowing the symptoms of a heart attack and getting immediate emergency treatment can limit or prevent heart muscle damage.
Learn More About Heart Attack (Myocardial Infarction)
Heart Block
Heart block occurs when electrical signals from the upper chambers of the heart (atria) cannot travel to the lower chambers (ventricles). The ventricles then beat too slowly, decreasing the amount of oxygen that gets to the body and brain. This causes a slow pulse and can result in a lack of energy, feeling lightheaded or fainting. Heart block can be a cause of syncope. Pacemakers are commonly used to treat heart block.
Learn More About Heart Block
Heart Failure (HF)
Heart failure (HF), previously called congestive heart failure, is a serious condition most commonly caused by weak pumping of the heart muscle. Poor heart pumping function can cause fatigue, leg swelling, and difficulty breathing, particularly with exertion. Lifestyle changes, medication, pacemakers, defibrillators and even open heart surgery can be used to treat heart failure.
Learn More About Heart Failure (HF)
Heart Valve Problems
Heart valve problems can be inherited or develop on their own, affecting the heart's ability to push blood efficiently from chamber to chamber, and out to the rest of the body. Medication, surgery, and the placement of new valves using catheters (thin tubes placed in the vessels and heart) are treatment options.
Learn More About Heart Valve Problems
Long QT Syndrome
Long QT syndrome is a rare genetic disorder that can cause a chaotic, fast heart rhythm. This fast heart rhythm can lead to fainting or seizures. In some instances, a prolonged episode of this chaotic heart rhythm can lead to sudden death.
Learn More About Long QT Syndrome
Premature Contractions
Extra, early, or "skipped" beats are the most common cause of irregular heart rhythms. These can start in the upper or lower chambers of the heart (atrial or ventricular premature contractions). They may or may not cause symptoms of palpitations, “fluttering”, or lightheadedness. Often they require no treatment, but if they are frequent or highly symptomatic a medical and cardiac evaluation should be undertaken.
Learn More About Premature Contractions
Sick Sinus Syndrome (SSS)
Sick sinus syndrome is not a disease, but a group of signs or symptoms that show that the heart's natural electrical pacemaker, the sinus node, is not working properly. In SSS, the heart rate can alternate between slow (bradycardia) and fast (tachycardia), often in combination with atrial fibrillation or atrial flutter. Treatment of SSS usually involves implanting a pacemaker, often along with medication.
Learn More About Sick Sinus Syndrome (SSS)
Sinus Tachycardia
A harmless faster rhythm, sinus tachycardia is a normal increase in heart rate that happens with fever, excitement, and exercise. There is no need for treatment, except in cases when it is caused by an underlying problem, such as anemia (a low blood count) or hyperthyroidism (overactive thyroid gland), or rarely, happens frequently and without a clear cause (inappropriate sinus tachycardia).
Learn More About Sinus Tachycardia
Stroke
Strokes (brain attacks), although not true heart disorders, are caused by blockage or reduced blood flow to the brain. While some strokes occur when a blood vessel bursts, most happen due to clogged or blocked vessels to the brain, in the same way clogged vessels in the heart can cause a heart attack. Abnormal heart rhythms such as atrial fibrillation and atrial flutter can lead to the formation of blood clots in the heart. Such blood clots can break off and travel to the brain, block a vessel and cause a stroke. All strokes pose serious health threats.
Learn More About Stroke
Sudden Cardiac Arrest (SCA)
Sudden Cardiac Arrest (SCA) occurs when the heart stops beating, abruptly and without warning
Learn More About Sudden Cardiac Arrest (SCA)
Supraventricular Tachycardia (SVT)
Supraventricular tachycardia, most commonly referred to as SVT includes multiple different forms all with similar symptoms. The most common types of SVT are: atrioventricular nodal reentrant tachycardia (AVNRT), atrioventricular reentrant tachycardia (AVRT) and atrial tachycardia (AT).
Learn More About Supraventricular Tachycardia (SVT)
Ventricular Fibrillation (VF)
Sudden Cardiac Arrest (SCA) caused by ventricular fibrillation (VF) is the cause of half of all heart related deaths. VF is sudden, happens without warning, and stops the heart from working. In VF, the heartbeat is fast and chaotic, causing the lower heart chambers(ventricles) to lose their ability to pump effectively. This results in a drop in blood pressure and loss of consciousness. If normal rhythm is not restored it will result in death. . Sometimes, a heart attack (blockage of the heart pipes/arteries) can lead to VF. Bystander CPR can provide circulation and improve the survival rates in people with SCA until defibrillation is performed to restore the normal rhythm. Patients at risk for VF and survivors of SCA can be treated with implantable cardiac defibrillators (ICDs) to provide life-saving prompt treatment.
Learn More About Ventricular Fibrillation (VF)
Ventricular Tachycardia (VT)
Ventricular tachycardia is a rapid heart rhythm that occurs in the lower chambers or ventricles of the heart. It often occurs in people with underlying heart disease like coronary artery disease, heart failure, or history of a previous heart attack. In these situations, it can be a life-threatening arrhythmia which can result in fainting or death if it persists and is untreated. Ventricular tachycardia (VT) can also happen in people with normal hearts and is called idiopathic VT. Because VT is often associated with symptoms and in many people can lead to ventricular fibrillation (a dangerously fast and disorganized heartbeat), it is a serious condition that needs aggressive treatment and follow up.
Learn More About Ventricular Tachycardia (VT)

Keep Exploring

Pediatrics and Congenital Heart Disease (CHD)
This section is for pediatric patients and families living with heart rhythm disorders and heart rhythm disorders related to congenital heart disease (CHD).
Early Warning Signs
If you are experiencing a racing, pounding, rumbling or flopping feeling in your chest or if you have been fainting, having repeated dizzy spells, feeling lightheaded or you are extremely fatigued, it's time to see a doctor to discuss your heart health.
Common Treatments
Learning about the underlying cause of any heart rhythm disorder provides the basis for selecting the best treatment plan. Information and knowledge about care options, and their risks and benefits help you work with your health care provider to make the best choices.
Lifestyle
Since other heart disorders increase the risk of developing abnormal heart rhythms, lifestyle changes often are recommended. Living a “heart healthy” lifestyle can ease the symptoms experienced with heart rhythm disorders and other heart disorders, and can be beneficial to overall patient health.
The Normal Heart
The heart is a fist-sized muscle that pumps blood through the body 24 hours a day, 365 days a year, without rest. The normal heart is made up of four parts: two atria on the top of the heart (right atrium and left atrium), and two ventricles (right ventricle and left ventricle) which are the muscular chambers on the bottom of the heart that provide the major power to pump blood.