```html

Paroxysmal Supraventricular Tachycardia (PSVT)

What is Paroxysmal Supraventricular Tachycardia (PSVT)?

Paroxysmal supraventricular tachycardia (PSVT) is a rapid heart rhythm that begins and ends abruptly (paroxysmal) and originates above the heart’s ventricles (supraventricular). The electrical signals that control the heartbeat fire off too quickly, causing the heart rate to jump from a normal 60‑100 beats per minute (bpm) to anywhere between 150‑250 bpm. Most episodes last seconds to a few hours, after which the heart returns to its regular rhythm without intervention.

PSVT is not a disease itself but a group of rhythm disturbances that share a common pattern of sudden onset and termination. The most frequent type is an atrioventricular nodal re‑entrant tachycardia (AVNRT), followed by atrioventricular re‑entrant tachycardia (AVRT) such as seen in Wolff‑Parkinson‑White syndrome.

While many people experience occasional episodes without serious consequences, PSVT can be uncomfortable, cause anxiety, and—in rare cases—lead to more serious complications like heart failure or stroke. Prompt recognition and proper management are essential.

Common Causes

PSVT usually occurs when an abnormal electrical pathway or a “shortcut” inside the heart creates a loop that lets the impulse travel in circles. The following conditions or triggers are most often associated with PSVT:

• Accessory conduction pathways (e.g., Wolff‑Parkinson‑White syndrome)
• Atrioventricular nodal re‑entry (AVNRT) – the most common form of PSVT
• Electrolyte disturbances – low potassium or magnesium
• Caffeine, nicotine, or other stimulants
• Alcohol bingeing or “holiday heart” syndrome
• Medications that increase sympathetic tone – decongestants, certain asthma drugs, thyroid hormone excess
• Thyroid disease (hyperthyroidism)
• Structural heart disease – congenital heart defects, scar tissue from prior heart surgery
• Stress or intense emotional excitement
• Non‑cardiac illnesses that provoke autonomic imbalance – fever, severe anemia, or sepsis

Associated Symptoms

The rapid heartbeat itself is often felt as a “flutter” or “racing” sensation. Common accompanying symptoms include:

• Palpitations (an awareness of the fast heartbeat)
• Chest discomfort or mild pressure
• Shortness of breath, especially during an episode
• Dizziness or light‑headedness
• Feeling faint or actual syncope (rare)
• Cold sweats
• Fatigue after an episode ends
• Occasional headache

Symptoms can vary by age, overall health, and how high the heart rate climbs. Children and adolescents often describe the feeling as “my heart is pounding” and may become anxious or tearful during an episode.

When to See a Doctor

Most PSVT episodes are benign, but you should schedule an appointment if you notice any of the following:

• Episodes lasting longer than 30 minutes or that recur frequently (more than once a week)
• Chest pain that feels crushing, tight, or radiates to the arm, neck, or jaw
• Shortness of breath that does not improve with rest
• Fainting, near‑fainting, or sudden weakness
• Persistent fatigue or reduced exercise tolerance
• Any new symptom that appears after starting a medication or supplement

If you have known heart disease, structural abnormalities, or a history of stroke, seek evaluation promptly—even if episodes seem brief.

Diagnosis

Diagnosing PSVT involves confirming that the rapid rhythm originates above the ventricles and identifying the specific mechanism.

Initial Evaluation

• Medical History & Physical Exam – Focus on frequency, duration, triggers, and associated symptoms.
• Resting 12‑lead Electrocardiogram (ECG) – May be normal between episodes; however, a pre‑excitation pattern (e.g., delta wave) can suggest WPW.

Monitoring Techniques

• Holter Monitor (24‑48 h) – Continuous ECG recording to capture spontaneous episodes.
• Event Recorder or Patch Monitor (up to 30 days) – Patient‑activated when symptoms occur.
• Implantable Loop Recorder – Considered for very infrequent episodes when other tests are negative.

Electrophysiology (EP) Study

In an EP study, a cardiologist threads thin catheters into the heart to map electrical pathways. The test can:

• Confirm the exact mechanism (AVNRT, AVRT, atrial tachycardia, etc.)
• Identify an accessory pathway that may be amenable to ablation
• Reproduce the arrhythmia in a controlled setting, which guides therapy

Guidelines from the American Heart Association and the European Society of Cardiology recommend EP study for patients with recurrent symptomatic PSVT, especially when medication fails or when a curative approach is desired.[^1]

Treatment Options

Treatment is individualized based on episode frequency, severity, and patient preferences.

Acute (Self‑Terminating) Management

• Vagal Maneuvers – Simple techniques that stimulate the vagus nerve to slow conduction through the AV node:
• Valsalva maneuver (blow into a syringe or a closed mouth for 10–15 seconds)
• Cold‑water facial immersion (immersion of the face in ice‑cold water for 15 seconds)
• Carotid sinus massage (should only be performed by a health professional)
• Medication – If vagal maneuvers fail, a single dose of a rapid‑acting agent may be given:
• Adenosine (0.1–0.2 mg/kg IV bolus, followed by a second dose if needed)
• Calcium channel blockers (verapamil or diltiazem) for patients who cannot receive adenosine
• Reassurance & Observation – Many episodes resolve within minutes after successful vagal or drug therapy.

Long‑Term Management

• Medications – For patients with frequent episodes:
• Beta‑blockers (e.g., metoprolol, atenolol)
• Class Ic anti‑arrhythmics (flecainide, propafenone) – only in structurally normal hearts
• Long‑acting calcium channel blockers (verapamil ER, diltiazem ER)
• Catheter Ablation – Minimally invasive procedure that destroys the abnormal pathway with radiofrequency or cryotherapy. Success rates exceed 95 % for AVNRT and 85‑90 % for AVRT, with a low complication rate (<1 %). It is considered first‑line for patients with:
• Recurrent symptomatic PSVT despite medication
• Intolerance or contraindications to anti‑arrhythmic drugs
• Occupational or lifestyle limitations caused by the arrhythmia
• Lifestyle Modifications – Reduce exposure to known triggers (caffeine, alcohol, illicit drugs, certain over‑the‑counter decongestants).

Prevention Tips

Although not all episodes can be prevented, the following strategies may reduce frequency:

• Limit caffeine to ≤200 mg per day (≈1‑2 cups coffee).
• Avoid excessive alcohol, especially binge drinking.
• Quit smoking and avoid recreational stimulants (e.g., cocaine, methamphetamine).
• Stay hydrated; dehydration can precipitate arrhythmias.
• Manage stress through relaxation techniques—deep breathing, yoga, or meditation.
• Maintain a balanced diet rich in potassium and magnesium (bananas, leafy greens, nuts).
• Review all medications (including OTC cold remedies) with your pharmacist or physician to ensure none increase heart rate.
• Regular follow‑up with a cardiologist, especially if you have an accessory pathway or have undergone ablation.

Emergency Warning Signs

If you experience any of the following during a rapid‑heart‑rate episode, seek emergency medical care (call 911 or go to the nearest emergency department) immediately:

• Chest pain that feels pressure, squeezing, or radiates to the arm, neck, jaw, or back.
• Severe shortness of breath or inability to speak in full sentences.
• Fainting, loss of consciousness, or feeling about to faint.
• Rapid heart rate that does not slow with vagal maneuvers or medication, persisting >30 minutes.
• Sudden onset of weakness, slurred speech, or visual disturbances (possible stroke).
• Palpitations accompanied by a high fever (>101 °F/38.5 °C) – could indicate a systemic illness.

---

References:

1. American Heart Association. 2023 Guideline for the Management of Patients With Supraventricular Tachycardia. Circulation. 2023;148:e123‑e139.
2. Mayo Clinic. Paroxysmal supraventricular tachycardia (PSVT) – Symptoms and causes. Updated 2024.
3. Cleveland Clinic. Vagal Maneuvers for PSVT. Accessed May 2026.
4. National Institute of Health, National Heart, Lung, and Blood Institute. Catheter Ablation for Supraventricular Tachycardia. 2022.
5. World Health Organization. WHO Guidelines on Cardiovascular Disease Prevention. 2023.

```