DR. PETCHA

Conditions

Supraventricular Tachycardia

SVT doesn’t have to control your life. With the right expertise, a clear diagnosis, and tailored treatment, you can regain rhythm—both in your heart and in your daily life.

Woman in hospital gown touching her chest, appearing to experience shortness of breath or chest discomfort

Shortness of breath and chest discomfort can be warning signs of abnormal heart rhythm

When Your Heart Races Without a Warning: Understanding Supraventricular Tachycardia (SVT)

It often starts in the most unexpected moments—during a morning jog, a stressful meeting, or even while sitting quietly. Suddenly, your heart begins to race, flutter, or pound in your chest. It feels like your body’s alarm system is triggered for no reason.

For many of my patients, this puzzling experience is their first brush with a condition called Supraventricular Tachycardia (SVT). While the name may sound intimidating, understanding it is the first step toward taking back control of your heartbeat—and your life.

What Is Supraventricular Tachycardia (SVT)?

SVT is a type of arrhythmia, or abnormal heart rhythm, that begins in the upper chambers of the heart—the atria. It causes the heart to beat much faster than normal, often between 150 and 250 beats per minute. This can be frightening, especially when it happens without warning. The good news? SVT is usually not life-threatening, but it can affect your quality of life if not addressed. It’s different from ventricular tachycardia, which starts in the lower chambers and may require emergency care.

When these fast rhythms come and go suddenly, we call it paroxysmal supraventricular tachycardia (PSVT).

Types of SVT: What’s Behind the Rapid Beat?

Not all SVTs are the same. Understanding the type of SVT helps us decide the best treatment. Here are the most common:

  • Atrioventricular Nodal Reentrant Tachycardia (AVNRT):The most common SVT. It happens due to a short-circuit loop near the AV node.
  • Atrioventricular Reciprocating Tachycardia (AVRT):Caused by an extra electrical pathway between the upper and lower chambers, often seen in Wolff-Parkinson-White (WPW) syndrome.
  • Atrial Tachycardia:Arises from a small area in the atrium outside the usual conduction pathway.
  • Paroxysmal SVT (PSVT):Short, sudden bursts of fast heartbeat that stop on their own.
  • Sinus Tachycardia:A normal response to physical or emotional stress, though sometimes misdiagnosed as SVT.

What Does SVT Feel Like? Common Symptoms

SVT symptoms can vary, but common complaints include:

  • A rapid or pounding heartbeat
  • Heart palpitations or fluttering in the chest
  • Chest discomfort or tightness
  • Shortness of breath
  • Dizziness or lightheadedness
  • Unusual fatigue
  • Rarely, fainting

Episodes can last seconds to hours. Triggers include stress, caffeine, dehydration, and physical exertion.

Why Does SVT Happen?

While SVT can affect anyone, certain risk factors may increase the likelihood of experiencing it.

Health-related causes:

  • Coronary artery disease
  • Heart failure or congenital heart defects
  • Atrial fibrillation
  • Overactive thyroid (hyperthyroidism)
  • Chronic lung disease

Lifestyle and external triggers:

  • Excessive caffeine or alcohol
  • Smoking
  • Stress or anxiety
  • Sedentary habits
  • Certain medications or stimulants
  • Dehydration

Genetic factors:

  • More common in younger adults
  • Can run in families

How Is SVT Diagnosed?

Diagnosing SVT starts with a thorough history and physical exam, followed by tools that record your heart’s electrical activity:

  • Electrocardiogram (ECG/EKG): Captures your heart rhythm in real time
  • Holter monitor: Worn for 24–48 hours to detect intermittent rhythms
  • Event monitor: Used for longer durations if episodes are infrequent
  • Exercise stress test: Measures heart response to exertion
  • Electrophysiological study (EPS): A precise map of your heart’s electrical circuits, often done before treatment like catheter ablation

Treatment Options for SVT

The goal is simple: restore a normal heart rhythm and prevent future episodes.

1. Immediate Relief

  • Vagal maneuvers (like bearing down or applying cold water to the face) may reset the rhythm
  • In emergencies, IV medications like adenosine can stop the arrhythmia quickly

2. Long-Term Management

  • Catheter Ablation:A minimally invasive procedure that uses energy to destroy the faulty electrical pathway. Often curative, with success rates above 90%.
  • Medications:Options include beta-blockers, calcium channel blockers, or antiarrhythmic drugs, depending on the frequency and severity of episodes

3. Lifestyle Modifications

  • Avoid stimulants (caffeine, alcohol, nicotine)
  • Stay hydrated and manage stress
  • Control blood pressure, thyroid levels, and blood sugar

What Happens If SVT Is Left Untreated?

Though usually not dangerous, untreated SVT can lead to:

  • Heart failure in patients with underlying heart conditions
  • Reduced cardiac output, affecting oxygen delivery to the body
  • Falls or fainting, especially in older adults
  • In rare cases, sudden cardiac death, especially with structural heart disease

A Hopeful Outlook: Living With SVT

With modern treatments, the prognosis for SVT is excellent. Many people live symptom-free after catheter ablation, while others manage well with medication and healthy habits. The key is to work with a heart rhythm specialist who understands the full spectrum of arrhythmias.