Tachycardia refers to a fast resting heart rate, usually over 100 beats per minute in adults. Some people have no symptoms, but they may notice palpitations, lightheadedness, and other changes.

Depending on its underlying cause and how hard the heart has to work, tachycardia can lead to severe complications.

There are different types of tachycardia based on which part of the heart the problem comes from, according to American Heart Association.

Some people with tachycardia have no symptoms, and complications never develop. However, tachycardia can increase the risk of heart failure, sudden cardiac arrest, and death.

In this article, learn more about the symptoms, causes, and treatment options associated with tachycardia.

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Tachycardia refers to a high resting heart rate. In adults, the heart usually beats between 60 and 100 times per minute.

Doctors usually consider a heart rate of over 100 beats per minute to be too fast. Factors such as age and fitness levels can affect it. Some people can also have an exaggerated response to exercise, and that is also considered a type of tachycardia.

When tachycardia is present, either the upper or lower chambers — or both — beat significantly faster.

When the heart beats too rapidly, it pumps less efficiently. Blood flow to the rest of the body, including the heart, reduces. The pressure in the lungs can also go up, leading to fluid accumulation.

The heart is a muscle. When the muscle is beating too fast, it can cause weakening or “tiring out” of the heart muscle over time. This is called tachycardia-induced cardiomyopathy.

What is arrhythmia?

Atria, ventricles, and the electrical circuitry of the heart

The human heart consists of four chambers: the atria, which are the two upper chambers, and the ventricles, which are the two lower chambers. There are left and right atria and ventricles.

The heart has a natural pacemaker, called the sinoatrial node, in the right atrium. This produces electrical impulses. Each one triggers an individual heartbeat.

As the electrical impulses leave the sinoatrial node, they cross the atria, making the atrial muscles contract. This contraction pushes blood into the ventricles.

The electrical impulses continue to the atrioventricular (AV) node, which is a cluster of cells. The AV node slows down the electrical signals and then sends them on to the ventricles.

In doing so, it allows time for the ventricles to fill with blood. When the ventricular muscles receive the electrical signals, they contract, pumping blood either to the lungs or to the rest of the body.

A problem with the electrical signals can result in a faster-than-normal heartbeat. This is tachycardia.

The following sections will outline some common types of tachycardia.

Sinus tachycardia

In this type, the heart beats faster than usual, but the rhythm is regular, and the impulse comes from the sinoatrial node.

Causes include:

  • mental and physical stress
  • fever
  • the use of certain drugs
  • some health conditions
  • infection, thyroid, or blood count problems

Learn more about sinus tachycardia here.

Inappropriate sinus tachycardia

Doctors do not understand fully what causes inappropriate sinus tachycardia, but neurological factors appear to play a role.

It seems more likely to affect:

  • super athletes
  • people undergoing psychological stress
  • females
  • people following a COVID-19 infection
  • people with POTS (postural orthostasis tachycardia syndrome)

Researchers say treatment is challenging because doctors understand so little about the cause. A doctor may treat inappropriate sinus tachycardia with beta-blockers.

Atrial or supraventricular tachycardia

Atrial or supraventricular tachycardia is an accelerated heart rhythm that starts in the upper chambers of the heart.

It is the most common heart rhythm problem in children and young people. Many people first experience it between the ages of 25 and 40 years.

An episode may last from a few minutes to several hours. It is not usually serious, but in extreme cases, it can lead to unconsciousness and cardiac arrest.

Atrial fibrillation

Sometimes electrical activity in the atria can override the heart’s natural pacemaker. This causes the chambers to contract rapidly and irregularly. This is known as atrial fibrillation (A-fib).

Most people with A-fib also have another heart condition. It is more likely to affect those over the age of 65 years. Consuming alcohol and smoking tobacco may contribute, as might hypertension and sleep apnea.

Atrial fibrillation can increase the risk of a stroke.

Atrial flutter

This is similar to A-fib, but the rhythms are more organized. Many people have both A-fib and atrial flutter.

Ventricular tachycardia

Abnormal electrical signals in the lower chambers result in a rapid heart rate. This can result from cardiovascular problems, such as a previous heart attack, the use of certain drugs, or a genetic condition leading to long QT.

The speed of the heartbeat does not allow the ventricles to fill and contract properly, thereby reducing blood supply to the body.

The cause and severity of the symptoms determine how serious it is. Long episodes can be very serious and need immediate medical attention. They can cause the heart to stop.

Ventricular fibrillation

Ventricular fibrillation (V-fib) is a serious cardiac disturbance. The ventricles quiver instead of beating, resulting in poor blood supply to the body.

V-fib is a medical emergency. If a normal heart rhythm does not return quickly, blood circulation can cease, which can lead to death.

Tachycardia usually stems from a disruption in the normal electrical impulses that control the heart’s pumping action, or the rate at which the heart pumps.

Depending on the type and cause of tachycardia, the following factors may trigger it:

However, sometimes the exact cause may not be clear.

Depending on the type and what’s causing tachycardia, the following symptoms may occur:

However, many people have no symptoms and only find out that they have tachycardia during a routine examination.

If a person seeks medical advice for a suspected heart rhythm problem, the doctor will:

  • ask about their symptoms
  • carry out a physical exam
  • order tests

These tests may include:

  • Electrocardiogram: Electrodes attached to the skin can measure electrical impulses that the heart produces.
  • Echocardiogram: This is a type of ultrasound that produces a moving image of the heart.
  • Wearable devices: The person can carry a Holter monitor or event recorder. These devices can monitor heart rhythms or electrical impulses for days or weeks.
  • Blood tests: These help determine whether thyroid or other problems are contributing to tachycardia.
  • Graded exercise test: This can help identify how physical activity impacts heart rhythms.
  • Implantable loop recorder: A loop recorder is a device that a doctor can insert under the skin. They can do this in the office. It records the heart’s activity continuously and can stay in for several years. It can help diagnose or monitor heart arrhythmias that occur more intermittently.
  • Electrophysiology study: These are invasive tests that help doctors understand why an arrhythmia occurs and where it originates from.

Tachycardia treatment depends on various factors, including:

  • the cause
  • the age of the person
  • their overall health
  • heart function and structure

Treatment aims to address the cause, but a doctor may also try to:

  • slow the heart rate
  • prevent further episodes
  • reduce the risk of complications

If there is no clear underlying cause, it may take some time to find a suitable treatment option.

There are several ways to slow a rapid heartbeat during an episode. The following sections will look at these in more detail.

Vagal maneuvers

The vagus nerve helps regulate the heartbeat.

Some techniques, or maneuvers, can affect this nerve and help slow the heartbeat. Such techniques include:

  • applying abdominal pressure
  • applying cold water to the person’s face
  • applying gentle pressure to the area of the neck where the carotid artery is
  • holding the nostrils closed while the person blows out through the nose
  • blowing on your thumb
  • bearing down like you are having a bowel movement
  • coughing

These may be helpful in an emergency.

Medication

A doctor can administer antiarrhythmic drugs either orally or intravenously. These drugs aim to restore a normal heart rhythm and control the heart rate.

Some examples of antiarrhythmic drugs include:

  • adenosine (Adenocard)
  • diltiazem (Cardizem CD)
  • metropolol (Lopressor)
  • amiodarone (Cordarone)
  • sotalol (Betapace)
  • mexiletine (Mexitil)

Cardioversion and defibrillators

A healthcare professional can attach patches, or electrodes, to the person’s body and have a machine deliver an electric shock to their heart. This resets the electrical impulses in the heart and may restore a normal rhythm.

There are different ways of performing cardioversion or defibrillation.

These are as follows:

  • In an emergency setting: While waiting for medical help to arrive, a first responder or bystander may use an automatic external defibrillator if the person’s heart goes into a rhythm that prevents it from beating properly.
  • In the hospital: A cardiologist may use cardioversion as part of a scheduled treatment.
  • Ongoing treatment: An implantable cardioverter defibrillator can continuously monitor the person’s heartbeat. A cardiologist can implant the small device into the chest, where it detects abnormal heartbeats and delivers a shock to restore a normal rhythm when needed.

Cardioversion aims to treat the abnormal heartbeat and change it to a regular rhythm. A doctor may use medicines or electrical energy to do this. Electrical treatment provides quick, synchronized low energy shocks to restore the rhythm.

Defibrillation is an electrical treatment that provides more powerful shocks to the heart to restore a perfusing rhythm, which allows blood to start circulating again. Automated external defibrillators (AED) are available in many public places for emergency use. An implantable defibrillator is a device a doctor implants under the skin to provide a shock when needed.

Some measures can help prevent and manage tachycardia. The following sections will discuss these measures in more detail.

Lifestyle factors

Some ways to prevent tachycardia and other heart issues at home include:

  • avoiding the use of tobacco and illegal drugs
  • limiting the consumption of alcohol and caffeine, energy drinks, Adderall, cocaine, methamphetamine, and cardiac stimulants
  • reducing stress, if possible
  • getting enough sleep
  • following a nutritious diet and getting regular exercise

Medications

Medications that can help people manage tachycardia include:

Blood thinners can help manage the complications of atrial fibrillation. Examples include warfarin (Coumadin) and apixaban (Eliquis).

Radiofrequency catheter ablation

An electrophysiologist can insert catheters into the heart through the blood vessels.

Electrodes at the ends of the catheter can ablate, or damage small sections of the heart that are responsible for the abnormal heartbeat.

Surgery

Sometimes a doctor will recommend surgery to make repairs or changes that can help reduce the risk of tachycardia. A pacemaker or defibrillator can help manage some types of tachycardia.

A doctor will only recommend surgery if other therapies have not worked or if the person has another heart condition.

The following factors can increase the risk of tachycardia:

  • age, as some kinds affect different age groups
  • genetic factors
  • a personal or family history of heart disease
  • anxiety
  • a high consumption of caffeine and alcohol
  • high blood pressure
  • diabetes
  • mental stress
  • smoking
  • the use of illegal drugs
  • thyroid disease

The risk of complications depends on several factors, including:

  • the severity and duration of the tachycardia
  • the type
  • the overall health of the person
  • any other heart conditions they may have
  • the structure and function of the heart muscle

The most common complications include:

  • Blood clots: Blood clots can significantly increase the risk of heart attack or stroke.
  • Heart failure: Without treatment, the heart can become weaker, increasing the risk of heart failure.
  • Fainting: A person with a rapid heartbeat may lose consciousness, increasing their risk of a fall or other accident.
  • Sudden death: This usually only occurs with ventricular tachycardia or ventricular fibrillation.

A person may also experience:

  • palpitations
  • fainting and dizziness
  • tiredness and fatigue
  • shortness of breath
  • chest pain and tightness, or angina
  • low blood pressure and shock
  • heart failure

Here are some questions people often ask about tachycardia.

What can trigger tachycardia?

Tachycardia can happen for many reasons, including:

  • the use of some drugs, prescription medications, or substances such as caffeine
  • health issues, such as cardiovascular disease, anemia, and some lung problems
  • stress and anxiety
  • heart problems that a person is born with
  • electrolyte problems or dehydration

What heart rate is tachycardia?

In an adult, a doctor will diagnose tachycardia if a person’s heart rate is over 100 beats per minute. Most people have a heart rate of 60–100 beats per minute, but this can vary according to age and other individual factors.

What is the first-line treatment for tachycardia?

There are many options, but the choice depends on the type and cause of tachycardia and various individual factors. A doctor may prescribe antiarrhythmic drugs, such as amiodarone (Cordarone) or sotalol (Betapace) or beta-blockers, for instance, propanolol.

They may also recommend radiofrequency or catheter ablation, surgery, a pacemaker, and lifestyle changes, such as quitting smoking if a person smokes.

Tachycardia refers to rapid heart rhythms, usually over 100 beats per minute in an adult. Some causes include heart disease and various lifestyle factors.

Some tachycardias are a “normal” response and not an arrhythmia, for example sinus tachycardia. In this case, the doctor will treat the underlying condition rather than the tachycardia. However, if tachycardia is an arrhythmia or abnormal heart rhythm, a doctor will treat the tachycardia itself with medication, ablation or surgery.

It is possible to have tachycardia, such as atrial fibrillation, without symptoms. But it can lead to complications, such as a heart attack or stroke.

Anyone who has concerns about their heart health should seek medical advice, as early treatment can help prevent long-term and possibly life threatening complications.

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