A supraventricular arrhythmia is an irregular heart rate that begins above the ventricles, which are the two lower chambers of the heart. Most, but not all, supraventricular arrhythmias begin in the atria, the top chambers of the heart. They may cause the heart to beat too fast, too slow, or irregularly.
This article will explain what supraventricular arrhythmia is, and list different types. It will also give information about causes, outlook, and treatment options for the condition.
Electrical signals in the heart help control a person’s heart rate. Problems with the cells that initiate these electrical signals can lead to an irregular heart rate. People with supraventricular arrhythmias may experience:
- Tachycardia: The heart rate is too fast.
- Bradycardia: The heart rate is too slow.
- An irregular heartbeat: The heart might feel like it is skipping or adding beats.
The heart contains four separate chambers: two atria and two ventricles. Irregular heart rates can begin in any of the four chambers or in the regions surrounding these chambers. Supraventricular arrhythmias begin above the ventricles, usually in the atria.
Most types of supraventricular arrhythmias cause the heart to beat too fast. Doctors call this supraventricular tachycardia.
Some types of supraventricular arrhythmias
- Atrial flutter: This happens when
electrical signalsin the atria cause the heart to beat quickly or irregularly. A person may feel that their heart is beating too fast or adding extra beats.
- Atrial fibrillation: Doctors classify atrial fibrillation as a type of supraventricular arrhythmia. This is the most
commonheart arrhythmia in the United States. It happens when the atria beat faster than usual due to dysfunctional electrical signals. A person may experience periods of a very irregular and fast heart rate, at up to 180 beats per minute.
- Atrioventricular nodal reentrant tachycardia or atrioventricular reentrant tachycardia: These are types of paroxysmal arrhythmia. Paroxysmal means that it happens sometimes, not all the time.
Commonin young people, it can cause dizziness, a fast heart rate, or shortness of breath. This arrhythmia happens because an extra pathway in the atrioventricular node or an accessory pathway causes the heart to beat irregularly. One type of atrioventricular reentrant tachycardia is Wolff-Parkinson-White syndrome, which involves an extra electrical pathway between the upper and lower chambers of the heart.
- Sinus tachycardia: Sinus tachycardia is
usuallynot an arrhythmia, and can happen when a person exercises or feels anxious, which causes their heart to beat very fast. However, sometimes the heart sends out signals to beat faster when there is no reason to do so. Doctors call this inappropriate sinus tachycardia. Most people have symptoms similar to those they experience during heavy exercise, including breathlessness and a rapid heart rate.
Ventricular arrhythmias, which are different, are arrhythmias that begin in the ventricles, the lower two chambers of the heart.
Unlike supraventricular arrhythmias, ventricular arrhythmias are more likely to cause serious harm because they can reduce the flow of oxygen-rich blood in the heart and they are more unstable. People with ventricular arrhythmias have a
The most common types of ventricular arrhythmias
Premature ventricular contraction (PVC): This is a less serious arrhythmia than some others. It happens when the ventricles contract too early. It is not usually harmful, but can be of concern if a person has other heart health conditions or if there are too many PVCs, which can weaken the function of the heart.
- Ventricular fibrillation: This is the most dangerous ventricular arrhythmia. It causes several electrical signals at once to initiate irregular and chaotic contractions in the ventricles. This can cause a very high heart rate of up to 300 beats per minute and can be fatal.
- Ventricular tachycardia: This happens when the sinoatrial node fails to control the heart rate in the ventricles. This results in a fast but potentially unstable heart rate. A person may feel dizzy or faint.
Heart rhythm irregularities happen when irregular electrical impulses change the way the heart beats. Many different conditions can cause these irregularities. Some include:
- Medical conditions: A wide range of conditions, especially those affecting the endocrine system, may cause heart rate issues. A person may experience supraventricular arrhythmia due to conditions like:
- Certain medications: Any medication that changes the body’s adrenaline system may cause heart rhythm irregularities. These include medications for conditions like attention deficit hyperactivity disorder (ADHD). This can also include toxins, such as alcohol or cocaine.
- Structural or congenital issues: Some people may be born with conditions that cause heart issues. For example, atrioventricular (nodal) reentrant tachycardia occurs when an extra “open” electrical pathway occurs in the heart. The conduction through this pathway may be present from birth.
- Heart surgery: Surgery in the upper chambers of the heart could cause supraventricular tachycardia. For example, if a person receives surgery for a congenital heart defect, they may notice an irregular heartbeat.
A wide range of behavioral factors may trigger heart rhythm irregularities in people who are susceptible to them. These may include:
The most common symptom of a heart arrhythmia is the sensation that the heart is beating too fast, too slow, or that it is skipping or adding beats. This is true for all arrhythmias, so a person cannot determine which type they have based on symptoms alone.
Some other symptoms a person might notice
Supraventricular arrhythmias are not usually life-threatening. They also tend to be
Certain arrhythmias, such as atrial fibrillation,
In many cases, a doctor can diagnose a heart arrhythmia using an
In some people, diagnosis is more difficult because they only experience periodic heart arrhythmias. When this is the case, a portable heart monitor, called a Holter monitor, can detect irregular heartbeats. A doctor may send a person home to wear the device for a day or even weeks, depending on their symptoms.
A doctor will also ask questions about a person’s medical history, medication and drug use, and other symptoms. Blood work may help rule out other conditions.
The right treatment depends on several factors, including whether the heart arrhythmia is dangerous or upsetting, a person’s overall health, and how frequently a person experiences the arrhythmia. Some treatment options include:
- Medication: Certain drugs, such as beta-blockers, calcium channel blockers, and adenosine may help regulate the heart rate in some people.
- Valsalva maneuver: This can stop a rapid heart rate in some people. Simply hold the nose shut, then blow the nose for 15 seconds. Ask a doctor if this is a safe home option for managing arrhythmias.
- Cold water: People with a sudden rapid heart rate may find that putting cold water on their face slows their heart rate.
- Behavioral changes: Some people can reduce the frequency of arrhythmias with lifestyle changes such as avoiding stimulants like caffeine. Exercise and a heart-healthy diet may also reduce a person’s risk of heart disease, and help prevent some risk factors for arrhythmias, such as high blood pressure.
- Ablation: If medication does not work and a person’s arrhythmia is dangerous, a doctor may recommend catheter ablation. This procedure eliminates or scars damaged or dysfunctional tissue that is causing irregular electrical signals in the heart.
Heart arrhythmias can be very scary, especially for people who do not know why their heart is beating fast. It is important to get a diagnosis since some supraventricular tachycardias are harmless and all are treatable.
A person should not self diagnose at home based on their symptoms or assume a they do not need treatment. People should contact their doctor if they have any concerns.