Understanding Tachycardia: Causes, Symptoms, Treatment & Prevention

Tachycardia occurs when the heart beats faster than normal, generally over 100 beats per minute (bpm) at rest. For most adults, a normal resting heart rate ranges between 60 and 100 bpm.

A relatively common type of abnormal heart rhythm (arrhythmia), tachycardia can result from an issue with the heart’s electrical signaling system, which normally coordinates the contractions of the heart muscle to ensure a steady and efficient heartbeat. A rapid heartbeat can make the heart less efficient, reducing its ability to pump oxygen-rich blood to organs and tissues throughout the body.

Understanding tachycardia is important because it may signal an underlying heart issue. Early detection and proper management are key to preventing potentially serious health complications, such as heart attack and stroke.

What Are the Types of Tachycardia?

A muscular vital organ, the heart has two upper chambers (atria) and two lower chambers (ventricles). The right atrium receives oxygen-depleted blood from the body and pumps it to the right ventricle, which sends the blood to the lungs for oxygen replenishment. The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle, which sends the blood to organs and tissues throughout the body. Based on the origin of the abnormal electrical signals that are causing the heart rate to increase, tachycardia can be broadly categorized into two main types:

Supraventricular Tachycardia (SVT)

SVT results from abnormal electrical signals in the atria, which suddenly increase the heart rate. While usually not life-threatening, supraventricular tachycardia episodes can be distressing and may require treatment to improve comfort or prevent recurrence. The types of SVT include:

• Atrial fibrillation (Afib) – The atria contract irregularly and are out of sync with the coordinated rhythm of the ventricles.
• Atrial flutter – The atria maintain a rapid, steady rhythm that is not synchronized with the rhythm of the ventricles.
• Paroxysmal supraventricular tachycardia (PSVT) – An abnormal electrical pathway (short circuit) causes electrical signals to loop rapidly in a circular pattern, leading to intermittent and rapid atrial contractions.

Ventricular Tachycardia (VT)

VT occurs when abnormal electrical signals in the ventricles cause the heart to beat faster than normal. A rapid heartbeat can reduce the heart’s ability to pump sufficient blood to the body’s organs and tissues, potentially impairing their function. If not treated promptly, ventricular tachycardia can become life-threatening. The types of VT include:

• Monomorphic VT – The ventricles contract rapidly at a consistent rate and rhythm.
• Polymorphic VT – The ventricles contract rapidly at a rate that varies from one beat to the next. Torsades de Pointes is a rare type of polymorphic VT characterized by a distinctive heartbeat pattern that resembles twisting points or peaks.

What Are the Causes of and Risk Factors for Tachycardia?

Tachycardia can occur for a variety of reasons. In some cases, it is related to an underlying heart condition that interferes with the heart’s electrical signaling system, leading to a rapid heartbeat. Examples include:

• Hypertension – Chronic high blood pressure can damage the heart muscle and disrupt its electrical signals.
• Coronary artery disease – A narrowed or blocked coronary artery can restrict blood flow to the heart and interrupt its electrical signals.
• Heart failure – When the heart cannot pump blood effectively, the body may naturally compensate by increasing the heart rate to make up for the heart’s diminished pumping capacity.
• Heart attack – If the supply of blood and oxygen to the heart is cut off, the affected heart muscle cells may become damaged and begin to die, which can interfere with the heart’s electrical signals.

In addition to certain underlying heart conditions, known risk factors for tachycardia include:

• Advanced age – The risk of tachycardia increases with age.
• Family history – Individuals with a close family member who has arrhythmia or heart failure are at heightened risk.
• Fever – When the body is working hard to fight off an infection, its metabolic rate and temperature will rise, increasing its need for oxygen. To meet the heightened demand for oxygen-rich blood, the body may naturally increase the heart rate.
• Anemia – A low red blood cell count may elevate the heart rate as the body attempts to increase the supply of oxygen to the body’s organs and tissues.
• Hyperthyroidism – An overactive thyroid gland can produce too much thyroid hormone, which stimulates the heart’s natural pacemaker and accelerates the heart’s intrinsic rate.
• Electrolyte imbalances – A low level of potassium, magnesium or calcium can affect the heart’s rhythms.
• Stimulant use – Caffeine, alcohol, nicotine and medications that contain pseudoephedrine can quicken the heart rate.
• Anxiety – Chronic stress or emotional panic can lead to temporary tachycardia.
• Dehydration – If the body is using more fluids than it is taking in, the heart will be forced to work harder and beat faster.
• Obstructive sleep apnea – During sleep, episodes of interrupted breathing can cause oxygen levels to drop and trigger a surge in adrenaline, a stress hormone that causes the heart to beat rapidly.
• Obesity – Excess body weight can strain the heart and lead to hypertension and other conditions that increase the risk of tachycardia.

What Are the Symptoms of Tachycardia?

The warning signs of tachycardia often reflect the inability of the heart to efficiently pump blood. Common symptoms include:

• Rapid heartbeat (palpitations) – A noticeably fast or irregular pulse may be felt in the chest or throat.
• Shortness of breath – Some people have trouble breathing or feel as if they are unable to take in enough air.
• Chest discomfort – Pressure, tightness or pain in the chest can be a sign that the heart is struggling to pump effectively.
• Dizziness – Faintness, lightheadedness and instability can result from decreased blood flow to the brain.
• Fatigue – Unusual tiredness, even with minimal physical activity, can result from reduced oxygen supply to the body’s organs and tissues.
• Fainting (syncope) – Tachycardia can cause temporary loss of consciousness, usually due to a significant drop in blood pressure or decreased blood flow to the brain.
• Anxiety – Feelings of unease, panic or impending doom may accompany a sensation that the heart is racing.
• Weak pulse – A rapid heart rate may not allow enough time for the heart’s chambers to fill with blood, resulting in reduced blood flow and a weakened pulse.

While some people with tachycardia have mild or unnoticeable symptoms, others experience severe or life-threatening complications. Therefore, it is important to seek medical attention if symptoms develop, especially if they are sudden or severe.

How Is Tachycardia Diagnosed?

Tachycardia is typically diagnosed through a clinical assessment of the heart’s structure, function and electrical activity. In addition to a physical examination, this may include:

• Electrocardiogram (ECG or EKG) – Several adhesive electrodes are placed on the chest, arms and legs. The electrodes are connected to an EKG machine via wires. While the patient relaxes, the machine will record the heart’s electrical impulses and display the results in graphical form on a computer screen or printout.
• Holter monitor – A portable EKG, a Holter monitor is worn for 1 to 2 days to record the heart’s rhythms during normal activities.
• Echocardiogram – Also known as a heart ultrasound, this imaging test uses sound waves to create detailed images of the heart’s structure, including its walls, chambers and valves.
• Stress test – The patient’s heart rhythms are monitored while they run or walk on a treadmill, cycle on a stationary bike or take medication to elevate their heart rate.
• Tilt table test – The patient lies flat on a special table that tilts from a horizontal position to a vertical position. As the table moves upright, a physician will check the patient’s heart rate and blood pressure to evaluate how their body responds to changes in posture.
• Electrophysiology (EP) study – Thin, flexible catheters with electrodes attached are inserted into a vein (usually in the groin) and guided to the heart. The electrodes will record the heart’s electrical signals and can also stimulate the heart to trigger arrhythmia, which can help a physician identify the source of tachycardia.

How Do You Treat Tachycardia?

Tachycardia treatment focuses on controlling the heart rate, reducing the symptoms, addressing the underlying cause, improving heart function and preventing complications, such as blood clots and heart failure. Depending on the type, cause and severity of the condition, options may include:

• Lifestyle modifications – Reducing caffeine intake, managing stress, quitting smoking and increasing physical activity can help prevent tachycardia episodes.
• Medication – Antiarrhythmic drugs, beta blockers or calcium channel blockers may be prescribed to slow the heart rate or regulate its rhythms.
• Cardioversion – In cases of persistent arrhythmia, electrical shocks or medications may be used to reset the heart to a normal rhythm.
• Catheter ablation – This minimally invasive procedure involves placing a catheter to deliver energy (radiofrequency or cryoablation) to small areas of the heart where abnormal electrical signals are originating.
• Implantable device – A pacemaker or implantable cardioverter-defibrillator (ICD) can help monitor and correct abnormal heart rhythms.
• Surgery – In rare cases, surgery may be considered to address severe arrhythmia that does not improve with conservative treatment.

What Are the Potential Complications and Long-Term Effects of Tachycardia?

If left untreated, tachycardia can have various complications and long-term effects, including:

• Chronic fatigue – Reduced cardiac efficiency can lead to persistent tiredness and decreased exercise capacity.
• Frequent syncope – Inadequate blood flow during tachycardia episodes can cause dizziness or fainting, which may result in falls and injuries.
• Worsening of other heart conditions – Tachycardia can exacerbate underlying heart issues, such as coronary artery disease and heart failure.
• Heart failure – Over time, rapid beating can weaken the heart, diminishing its ability to pump blood effectively.
• Blood clots – An accelerated heart rate can create turbulence in the chambers, particularly the atria, potentially allowing blood to pool and increasing the risk of clot formation.
• Sudden cardiac arrest – As the heart beats rapidly and inefficiently, it may not fill with blood, which can significantly reduce blood flow to the body’s organs and tissues and potentially cause the heart to stop pumping altogether.

Early detection and appropriate management of tachycardia are essential to minimize these risks and protect overall heart health.

How Do You Prevent or Reduce Your Risk of Tachycardia?

To help prevent or reduce the risk of tachycardia, it is important to maintain a healthy lifestyle by:

• Managing stress levels
• Practicing relaxation techniques
• Avoiding excessive caffeine intake and alcohol consumption
• Quitting smoking and avoiding other forms of tobacco use
• Exercising regularly
• Having routine medical checkups
• Managing other health conditions, such as hypertension and diabetes
• Taking prescribed medications as directed

Living With Tachycardia

The impact of tachycardia on a patient’s daily life can vary greatly depending on the type and cause of the condition, the severity of its symptoms and other factors. For some people, the rapid heartbeat may be intermittent and cause few symptoms; for others, it can be persistent and lead to frequent episodes of palpitations, dizziness, chest discomfort and shortness of breath. These symptoms can potentially affect day-to-day activities, making it difficult to fully participate in work, school, exercise and social events.

Some people with tachycardia experience fear or anxiety about the possibility of having an episode, which can further exacerbate the related stress and discomfort. Additionally, if left untreated, a rapid heartbeat can lead to blood clot formation and other potentially serious complications, which can cause ongoing worry about long-term health risks.

Effective management of tachycardia often requires a combination of lifestyle adjustments, medications and possibly a medical procedure, which may improve the symptoms and quality of life. Patients who are diagnosed with tachycardia often work closely with their healthcare team to monitor their condition and reduce the associated risks.

Frequently Asked Questions (FAQs) About Tachycardia

The following FAQs and corresponding answers provide additional information about tachycardia:

What Is Tachycardia?

Tachycardia occurs when the heart beats faster than normal, which can affect its ability to pump blood efficiently.

What Causes Tachycardia?

Tachycardia can have many causes, including an underlying heart condition, age-related heart changes, fever, anemia, hyperthyroidism, electrolyte imbalances, anxiety, dehydration, sleep apnea, obesity and the use of stimulants, such as caffeine.

How Do I Know if I Have Tachycardia?

Possible warning signs of tachycardia include palpitations, shortness of breath, chest pain, dizziness, fatigue, syncope, weak pulse and anxiety. However, some people do not have noticeable symptoms.

Is Tachycardia Dangerous?

If left untreated, tachycardia can lead to potentially dangerous complications, such as frequent syncope, blood clots, stroke, heart failure and sudden cardiac arrest, especially if the condition is severe or prolonged.

How Is Tachycardia Treated?

Treatment options for tachycardia may include lifestyle modifications, medication and medical procedures, such as electrical cardioversion, catheter ablation or the implantation of a pacemaker or ICD to correct abnormal heart rhythms.

Can Tachycardia Be Prevented?

While some risk factors for tachycardia, such as a family history of heart disease, cannot be controlled, others often can be managed by maintaining a healthy lifestyle. This includes exercising regularly, quitting smoking, avoiding stimulants, reducing stress, having routine medical checkups and treating any underlying health conditions, such as hypertension and diabetes.

Benefit From World-Class Care at TGH

TGH is nationally recognized for providing advanced, superior care for patients with heart conditions. The multidisciplinary team in our high-volume Heart & Vascular Institute and Electrophysiology Center of Excellence includes respected specialists who focus exclusively on preventing, diagnosing and treating cardiac issues, including tachycardia and other arrhythmias. In addition, Tampa General is among the select few centers specializing in ablations to treat ventricular tachycardia, a condition that can become life-threatening in seconds. TGH serves as a renowned referral center for handling the most challenging cases, including complex arrhythmias and lead extractions.

We are proud to be the only hospital in the Tampa Bay region to be included in the list of “100 Hospitals and Health Systems with Great Heart Programs” compiled by Becker’s Hospital Review, and we are recognized by U.S. News & World Report as one of the Nation’s Best Hospitals for Heart & Vascular Care for 2024-25.

If you would like to learn more about tachycardia, please contact us at (813) 844-3900 or email us at heart-vascular@tgh.org to request an appointment with an expert in our Heart & Vascular Institute.