Supraventricular Tachycardia

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Supraventricular tachycardia (SVT) is a type of irregular heartbeat where your heart beats too fast. It mostly affects the upper chambers of your heart. Episodes can last from a few seconds to an hour, with your heart racing up to 220 beats per minute. You might feel dizzy, lightheaded, or have chest pain during an episode. Picture this: if an elevator’s doors close too quickly, people struggle to get in before they shut. Similarly, when your heart beats too fast, it doesn’t have enough time to fill with blood before it contracts.

During an SVT episode, your heart can race up to 220 beats per minute, lasting from a few seconds to several hours. Symptoms may include dizziness, lightheadedness, or simply feeling the rapid heartbeat. Although SVT typically isn’t life-threatening, it’s essential to seek medical attention if you experience symptoms.

How Does SVT Differ From VTACH?

SVT is often confused with ventricular tachycardia (VTACH), another type of irregular heartbeat. However, VTACH originates in the heart’s lower chambers (ventricles) rather than the upper chambers (atria). VTACH is more common in older individuals with underlying heart conditions and is generally considered more serious than SVT.

Who gets SVT?

SVT typically affects younger people, often starting in the teens or early twenties. However, it can occur at any age and is more common in women.

How Does Your Heart Normally Beat?

Understanding how your heart functions helps you grasp SVT better. The heart has four chambers: two upper chambers (atria) and two lower chambers (ventricles). The sinoatrial node (SA node), often called the heart’s natural pacemaker, generates electrical signals that regulate the heartbeat.

Normally, the SA node sends signals to the atria, causing them to contract and pump blood into the ventricles. Then, the signal travels to the ventricles, prompting them to contract and pump blood out of the body. This coordinated process results in the familiar “lub-dub” heartbeat pattern, typically occurring 50–99 times per minute at rest.

During SVT, however, the electrical signals in the atria misfire, causing them to contract prematurely. This disrupts the normal heart rhythm, leading to a rapid and irregular heartbeat.

What causes supraventricular tachycardia?

During an SVT episode, electrical signals in the upper chambers fire abnormally early, causing them to squeeze too soon. This disrupts the normal SA node signals and makes your heart beat very fast and irregularly.

Types of Supraventricular Tachycardia

SVT, or supraventricular tachycardia, manifests in various forms, each with its own unique triggers and characteristics.

1. Atrioventricular (AV) Nodal Reentrant Tachycardia: This is the most common type, particularly among young women. It involves an extra pathway near the AV node, causing an electrical signal to loop instead of progressing to the heart’s lower chambers, leading to a rapid heartbeat.
2. AV Reciprocating Tachycardia: characterized by an abnormal pathway connecting the heart’s upper and lower chambers, resulting in a circular movement of the signal. It’s more prevalent in younger individuals and those with Wolff-Parkinson-White syndrome.
3. Atrial tachycardia: This occurs when a short circuit in either atrium triggers an irregular electrical signal, often affecting individuals with heart disease.
4. Sinus tachycardia involves a rapid heartbeat at a normal rhythm, commonly triggered by factors like certain medications, illegal drugs, fever, or stress. While usually not dangerous, persistent sinus tachycardia warrants medical attention.
5. Paroxysmal SVT is characterized by occasional bursts of rapid heartbeat, typically seen in young individuals engaged in intense physical activity.

Other types of tachycardia include sinus nodal reentrant tachycardia, junctional ectopic tachycardia, nonparoxysmal tachycardia, premature atrial contractions, accessory pathway tachycardias (such as Wolff-Parkinson-White syndrome), multifocal atrial tachycardia, atrial fibrillation, and atrial flutter.

Risk Factors for SVT

SVT can be triggered by various factors, including medical conditions, congenital issues, heart surgery, and lifestyle choices.

1. Medical Conditions: Lung disease, thyroid disease, heart failure, or other heart diseases like Wolff-Parkinson-White syndrome can contribute to SVT.
2. Certain Medications: Some medications for asthma, allergies, and colds can affect heart rhythm, potentially triggering SVT.
3. Congenital Issues: Birth defects like extra electrical pathways or abnormal circuits in the heart can lead to SVT.
4. Heart Surgery: Scar tissue from previous heart surgeries can disrupt normal electrical signals in the heart, increasing the risk of SVT.
5. Other Triggers: Stress, anxiety, excessive caffeine or alcohol consumption, smoking, drug abuse, and pregnancy can also provoke SVT episodes.

Certain demographics, such as middle-aged or older individuals and pregnant women, are at higher risk for specific types of SVT. Additionally, underlying health conditions like heart disease, lung disease, thyroid disease, diabetes, and sleep apnea elevate the risk of developing SVT. Lifestyle factors like smoking and illicit drug use further contribute to the

Symptoms of Supraventricular Tachycardia

• Rapid heartbeat (palpitations)
• Chest pain
• Dizziness
• Fatigue
• Shortness of breath
• Fainting
• Sweating
• Weakness
• Pounding feeling in the neck

Diagnosing SVT

Your doctor will ask about your symptoms, when they started, and any potential triggers. They will also perform a physical exam and listen to your heart and lungs. An electrocardiogram (EKG) is a common test used to record your heart’s rhythm and identify abnormalities. Depending on your case, additional tests like Holter monitoring or an electrophysiology study might be needed.

Treating SVT

In some cases, SVT doesn’t require treatment. However, if it bothers you, there are options like:

• Carotid sinus massage (performed by a healthcare professional) to slow down the heart rate.
• Vagal maneuvers (like coughing or holding your breath) that can sometimes trigger the vagus nerve to slow the heart rate.
• Medications to control your heart rate.
• Cardioversion (electric shock) to restore a normal heart rhythm in emergencies.
• Catheter ablation (a procedure to destroy the abnormal electrical pathway causing SVT).
• Pacemaker (implanted device to regulate your heartbeat in rare cases).

Living With SVT

Living with SVT involves adopting healthy habits to support heart health and prevent episodes. Here are some lifestyle and home remedies to consider:

1. Regular Doctor Visits: Schedule regular check-ups with your doctor to monitor your heart health and receive guidance on managing blood pressure, cholesterol, and other factors affecting your heart.
2. Heart-Healthy Diet: Focus on a diet rich in fruits, vegetables, and whole grains while limiting salt, saturated fats, sugars, and carbohydrates.
3. Stay Hydrated: Drink plenty of water to prevent dehydration, which can trigger SVT episodes.
4. Exercise: Engage in regular physical activity such as walking, swimming, or gardening, as approved by your doctor.
5. Quit Smoking: Seek help to quit smoking, as it can exacerbate SVT and other heart-related issues.
6. Maintain a Healthy Weight: Work with your doctor to achieve and maintain a healthy weight suitable for you.
7. Moderate Alcohol Consumption: If you drink alcohol, do so in moderation, adhering to recommended limits based on your age and weight.
8. Limit Caffeine: Moderate your intake of coffee or tea to avoid excessive stimulation of your heart.
9. Avoid Illegal Drugs: Steer clear of drugs like cocaine or methamphetamines, which can trigger irregular heartbeats.
10. Stress Management: Practice stress-reducing techniques such as yoga, meditation, or mindfulness to manage stress levels effectively.
11. Adequate Sleep: Ensure you get enough quality sleep, as sleep deprivation can contribute to SVT episodes.

It’s also essential to be mindful of foods and beverages that may trigger SVT, such as those high in salt, saturated fats, sugars, and carbohydrates.

Foods to Avoid with SVT

Certain foods and beverages can act as triggers for SVT episodes and increase the risk of other heart-related issues. Alongside caffeine and alcohol, it’s advisable to steer clear of items high in:

• Salt
• Saturated fat
• Sugar
• Carbohydrates

Supraventricular Tachycardia Complications

While SVT is typically not life-threatening, in rare instances, it can lead to fainting or even cardiac arrest. Prolonged or frequent bouts of SVT may also weaken the heart, especially if concurrent health conditions are present.

Some treatments for SVT, such as medications or ablation procedures, may have side effects. It’s essential to discuss these potential complications with your doctor and develop strategies to manage them effectively.

SVT Prevention

Adopting a heart-healthy lifestyle is key to preventing SVT episodes. If you’ve already been diagnosed with SVT, keeping track of triggers is crucial. Maintain a diary documenting episodes, including heart rate, symptoms, and activities that may have precipitated the SVT, such as consuming caffeinated beverages or smoking.

Follow your doctor’s instructions precisely if medication has been prescribed for SVT management.

When to Seek Medical Attention

If you experience irregular heartbeats for the first time or if an episode persists for more than a few seconds, contact your doctor promptly.

Seek immediate medical attention if you encounter sudden chest pain accompanied by shortness of breath or if you’ve been diagnosed with SVT and your heart rate has remained elevated for 30 minutes or more.

Key Takeaways About SVT

SVT manifests as a rapid or irregular heartbeat, potentially triggered by faulty electrical signals in the heart or external factors like stress or exercise. While SVT is typically not life-threatening, it may require treatment in some cases. Treatment options may include medication and lifestyle modifications. It’s essential to work closely with your healthcare provider to manage SVT effectively.

Sources:

1. American Family Physician: “Common Types of Supraventricular Tachycardia: Diagnosis and Management.”
2. American Heart Association: “Other Heart Rhythm Disorders,” “Tachycardia — Fast Heart Rate,” “Tachycardia,” “Holter Monitor.”
3. Cleveland Clinic: “Atrial Tachycardia,” “How Does the Heart Beat,” “Sinus Tachycardia,” “SVT (Supraventricular Tachycardia).”
4. Harvard Health Publishing: “Different types of tachycardia.”
5. Texas Heart Institute: “Categories of Arrhythmias,” “Heart Anatomy.”
6. University of Michigan Health System: “Supraventricular Tachycardia (SVT).”
7. Mayo Clinic: “Supraventricular tachycardia,” “Electrocardiogram (ECG or EKG).”