Understanding Arrhythmia – Causes, Symptoms, Treatment & Prevention

An arrhythmia is an irregular heartbeat, which may be too fast, too slow or erratic. While some arrhythmias are harmless, others can disrupt the heart’s ability to pump blood effectively, compromising the delivery of oxygen and vital nutrients throughout the body. Arrhythmias are common, affecting millions of people worldwide.

Understanding arrhythmia is essential for maintaining optimal heart health. Early detection and management of an irregular heartbeat can help prevent potentially serious complications, such as heart failure, stroke and sudden cardiac arrest.

What Are the Types of Arrhythmia?

Arrhythmias are classified based on the speed or pattern of the heartbeat. The types include:

Tachycardia

Tachycardia is characterized by a resting heart rate exceeding 100 beats per minute (bpm). It is usually caused by abnormal electrical signals in either the heart’s upper chambers (atria) or lower chambers (ventricles). When the irregularity originates in the atria, the condition is classified as supraventricular tachycardia. The subtypes of supraventricular tachycardia include:

• Atrial fibrillation (Afib) – Rapid, irregular electrical signals in the atria trigger rapid, irregular heart rhythms.
• Atrial flutter – Similar to Afib, atrial flutter stems from a more organized and predictable electrical signaling pattern.
• Paroxysmal atrial tachycardia (PAT) – A short circuit rhythm in the atria causes a rapid heartbeat that stops and starts abruptly.

When abnormal electrical signals originate in the ventricles, the condition is classified as ventricular tachycardia (VT). The types of VT include:

• Monomorphic VT – The ventricles beat rapidly but consistently.
• Polymorphic VT – The ventricles beat rapidly with beat-to-beat variations.

Bradycardia

Bradycardia is a slower-than-normal heart rate, typically below 60 bpm at rest. This can impair the heart’s ability to pump sufficient blood to the body’s organs and tissues, potentially affecting overall function. Bradycardia is classified based on the origin of the abnormal heart rhythm. The types include:

• Sinus node dysfunction – An area of specialized cells in the right atrium, the sinus (sinoatrial) node serves as a natural pacemaker, generating and conducting electrical impulses that trigger the heart to beat. If the sinus node is damaged or malfunctions, its electrical impulses may become erratic, leading to an irregular or abnormally slow heartbeat.
• Tachycardia-bradycardia syndrome – Sinus node dysfunction sometimes triggers alternating episodes of slow and fast heart rhythms with long pauses between beats, such as those that occur with Afib.
• Heart block – Due to age-related degeneration, heart damage or other causes, the electrical signals that control the heartbeat may be delayed, interrupted or blocked as they travel from the atria to the ventricles. This can slow the heart rate and diminish the heart’s ability to pump blood effectively.

What Are the Causes of and Risk Factors for Arrhythmia?

Arrhythmias result from disruptions in the heart's electrical signals, which can have various underlying causes and risk factors. These include:

• Advanced age – The natural aging process can affect the heart’s electrical system, increasing the risk of arrhythmia.
• Family history of arrhythmias or heart failure – Genetic factors can predispose an individual to arrhythmia and other heart-related conditions.
• Heart disease – Cardiac conditions, such as coronary artery disease, can damage the heart’s electrical pathways, leading to arrhythmia.
• High blood pressure (hypertension) – Chronic hypertension can lead to heart enlargement and increase the risk of arrhythmia.
• Hyperthyroidism or hypothyroidism – Imbalances in thyroid hormone levels can affect heart rhythms.
• Sleep apnea – Interrupted breathing during sleep can lead to irregular heartbeats and other cardiovascular issues.
• Obesity – Excess body weight can strain the heart, increasing the risk of arrhythmia.
• Electrolyte imbalances – Irregularities in potassium, sodium or calcium levels can disrupt the heart's electrical signals.
• Congenital heart defect – A cardiac structural issue present at birth can lead to arrhythmia, particularly in the heart’s electrical system.
• Stress and anxiety – Emotional distress can trigger arrhythmia by affecting the autonomic nervous system.
• Stimulant use – Consumption of caffeine, alcohol or nicotine can overstimulate the heart and cause irregular rhythms.
• Dehydration – Insufficient fluid intake can lead to electrolyte imbalances and trigger arrhythmia.

What Are the Symptoms of Arrhythmia?

The warning signs of arrhythmia can vary depending on its type and severity. Possible symptoms include:

• Fluttering, racing or pounding heartbeat (palpitations) – A sensation of the heart beating rapidly or irregularly, often felt in the chest or throat.
• Slow or irregular pulse – The heart rate may be unusually slow or erratic, making it difficult to detect a consistent rhythm.
• Shortness of breath – Difficulty breathing or a feeling of not getting enough air, often occurring during physical activity or at rest.
• Dizziness and lightheadedness – A sensation of feeling faint, dizzy or unsteady, which may occur when standing up or during physical exertion.
• Fatigue and weakness – Feeling unusually tired or weak, even after normal activities, due to the heart's inability to pump blood efficiently.
• Fainting (syncope) or near-fainting episodes – Sudden loss of consciousness or near-fainting, often caused by insufficient blood flow to the brain.

It is important to note that some arrhythmias are asymptomatic and detected during a routine medical exam.

How Is Arrhythmia Diagnosed?

Arrhythmia is typically diagnosed through a medical history review, physical examination and one or more diagnostic tests, which may include:

• Electrocardiogram (ECG/EKG) – An EKG is the primary tool used to measure the electrical activity of the heart and identify irregular rhythms.
• Holter monitor – A portable EKG device can be worn for 24 to 48 hours to continually record the heart’s electrical activity.
• Cardiac event recorder – Similar to a Holter monitor, this wearable EKG device can be used over several weeks to capture intermittent arrhythmia.
• Echocardiogram – A noninvasive imaging test, an “echo” uses high-frequency sound waves to create detailed pictures of the heart, which can help a physician evaluate its structure and function.
• Stress test – A cardiac stress test evaluates how well the heart functions during physical exertion or simulated exercise, typically using a treadmill, stationary bicycle or heart-stimulating medication.
• Electrophysiological (EP) study – An EP study is a specialized procedure that maps the heart's electrical pathways to help a physician pinpoint the source of arrhythmia.
• Tilt table test – Often used to determine the cause of unexplained dizziness or syncope, this diagnostic procedure can help a physician evaluate how changes in body position affect heart rate and blood pressure.

The results of these tests can help the physician identify an arrhythmia and determine the type, cause and severity of an arrhythmia, which can be used to guide treatment decisions.

How Do You Treat Arrhythmia?

Arrhythmia treatment can vary depending on its type and severity. Options may include:

• Observation – If the arrhythmia poses no significant risks, a physician may suggest a “wait and watch” approach to monitor the condition without immediate intervention.
• Lifestyle changes – Many people benefit from adopting healthier habits to minimize arrhythmia triggers, such as reducing stress, limiting caffeine intake and alcohol consumption and maintaining a balanced diet.
• Medication – A physician may prescribe drugs to control the heart rate, restore its rhythm or prevent blood clots.
• Electric shock to restore normal heart rhythm (cardioversion) – A controlled electrical pulse is delivered to the heart to reset its rhythm.
• Catheter ablation – A minimally invasive procedure that uses heat or cold energy can destroy the abnormal tissue that is causing the arrhythmia.
• Pacemaker – A small device may be implanted under the chest skin to regulate the heart’s rhythms and maintain a normal heart rate. A type of device called a biventricular (B-V) pacemaker, which is a type of cardiac resynchronization therapy (CRT) device, is designed to synchronize the contractions of the left ventricle. These devices include an additional lead that extends to the left ventricle, alongside the standard pacemaker leads placed in the right side of the heart. They are often recommended for individuals with heart failure and uncoordinated left ventricular contractions.
• Implantable cardioverter-defibrillator (ICD) - An ICD is a small device placed under the skin that monitors heart rhythms and delivers electrical shocks to correct an abnormally fast heart rhythm.

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

If left untreated, arrhythmia can have several potentially serious complications and long-term effects. These include:

• Heart failure – Chronic arrhythmia can strain the heart and impair its ability to pump enough blood to meet the body’s needs.
• Blood clots – Irregular heart rhythms, particularly in the atria (as in Afib), can disrupt normal blood flow and lead to the formation of semi-solid or gel-like masses in the arteries and veins. Blood clots can block blood flow to vital organs and lead to life-threatening complications, such as stroke.
• Stroke – Blood clots caused by arrhythmia can block blood flow to the brain, leading to a stroke. The resulting neurological damage, which may be permanent, can affect motor skills, speech and cognitive function.
• Heart muscle damage – Long-term arrhythmia can deprive the heart muscle of oxygen-rich blood, causing damage that further impairs the heart’s function and renders it less effective at circulating blood throughout the body.
• Cardiac arrest – Certain arrhythmias, such as VT, can cause the heart to stop abruptly. Sudden cardiac arrest is a life-threatening emergency that requires immediate medical attention to restore the heart’s rhythms.

How Do You Prevent or Reduce Your Risk of Arrhythmia?

Some potentially effective ways to prevent or reduce the risk of arrhythmia include:

• Managing other health conditions, such as hypertension, high cholesterol, hyperthyroidism, hypothyroidism and sleep apnea
• Consuming a nutritious, well-balanced diet
• Engaging in regular physical activity
• Achieving and maintaining a healthy body weight
• Staying well hydrated and avoiding excessive alcohol consumption and caffeine intake
• Quitting smoking and avoiding other forms of tobacco use
• Managing stress and anxiety

Additionally, it is important for everyone to stay on top of their heart health by having regular medical check-ups and following the advice of a physician regarding arrhythmia prevention and management.

Living With Arrhythmia

The impact of arrhythmia on a patient’s daily life can vary widely depending on the type and severity of the condition and other factors. Some individuals experience only mild, occasional symptoms, such as palpitations, dizziness and fatigue, while others have more severe, persistent or disruptive issues, such as shortness of breath and syncope. Most people benefit from making positive lifestyle changes, such as avoiding arrhythmia triggers, monitoring their heart health and taking their medications as prescribed.

Frequently Asked Questions (FAQs) About Arrhythmia

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

What Is Arrhythmia?

Arrhythmia is an irregular heartbeat, which may be too fast, too slow or erratic. While some arrhythmias are harmless, others affect the heart’s ability to pump blood to organs and tissues throughout the body, sometimes leading to complications, such as heart failure and blood clots.

What Causes Arrhythmia?

Most arrhythmias are caused by an issue with the heart’s arteries, valves or muscles, which can result from age-related degeneration. Other known risk factors include genetics, heart disease, hypertension, hyperthyroidism, hypothyroidism, sleep apnea, obesity, electrolyte imbalances, stress, stimulant use and dehydration.

What Are the Symptoms of Arrhythmia?

Arrhythmia symptoms can include palpitations, weak pulse, shortness of breath, dizziness, fatigue and syncope. However, some people do not experience noticeable symptoms.

How Is Arrhythmia Diagnosed?

Arrhythmia is typically diagnosed through a physical exam and a combination of tests, which may include EKG, Holter monitor, echocardiogram, stress test, EP study and/or tilt table test. The results can help a physician evaluate the heart’s electrical activity and rhythms.

How Is Arrhythmia Treated?

Arrhythmia treatment can vary depending on its type, severity and other factors. Options may include observation, lifestyle changes, medication, cardioversion, catheter ablation and, in some cases, a pacemaker or defibrillator.

Can Arrhythmia Be Life-Threatening?

If left untreated, some arrhythmias can lead to serious complications, such as stroke and sudden cardiac arrest, which can be life-threatening and require emergency medical attention.

Can Arrhythmia Be Prevented?

While some arrhythmias cannot be prevented, it may be possible to reduce the risk by managing hypertension and other health conditions, consuming a well-balanced diet, exercising regularly, achieving and maintaining a healthy body weight, staying well hydrated, avoiding excessive alcohol consumption and caffeine intake, quitting smoking and managing stress and anxiety.

What Should I Do if I Experience Symptoms of Arrhythmia?

If you experience arrhythmia symptoms, such as palpitations, shortness of breath or dizziness, you should promptly see a physician who can provide an accurate diagnosis and suggest appropriate treatment if needed.

Is Arrhythmia Common?

Yes, irregular heart rhythms are relatively common, especially in older adults. However, arrhythmia affects people of all ages.

Can Arrhythmia Be Cured?

Some arrhythmias can be treated effectively with medication or a medical procedure, while others may require ongoing treatment to control the symptoms and reduce the risk of complications.

Benefit From World-Class Care at TGH

TGH is nationally acclaimed for delivering advanced, high-quality care for patients with heart conditions. The multidisciplinary team at our Heart & Vascular Institute and Electrophysiology Center of Excellence consists of highly regarded specialists dedicated to preventing, diagnosing and treating a wide range of cardiac issues, including all types of arrhythmias. We are a leader in cardiac resynchronization therapy (CRT) and one of only five centers in the U.S. to offer cardiac conduction system pacing, which helps foster normal heart activity with fewer side effects and a reduced risk of heart attack.

In addition, we are honored to be the only hospital in the Tampa Bay area featured on Becker’s Hospital Review’s list of “100 Hospitals and Health Systems with Great Heart Programs.” Plus, U.S. News & World Report has recognized TGH as one of the Nation’s Best Hospitals for Heart & Vascular Care for 2024-25, and Newsweek has ranked TGH as one of America’s Best Specialized Hospitals for Cardiac Care in 2024.

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