What is the treatment for paroxysmal supraventricular tachycardia (PSVT)?

Treatment of Paroxysmal Supraventricular Tachycardia (PSVT)

The definitive treatment algorithm for PSVT begins with vagal maneuvers, followed by adenosine for acute termination, and catheter ablation as the most effective long-term solution with success rates of 94-98%. 1, 2

Initial Assessment and Management

Hemodynamic Stability Assessment

• Hemodynamically unstable patients: Immediate synchronized cardioversion is required 1
• Hemodynamically stable patients: Proceed with stepwise approach below

Acute Termination of PSVT

1. Vagal Maneuvers (Class I, Level B-R) 1

   • Modified Valsalva maneuver (43% effective) 2
   • Standard Valsalva maneuver
   • Carotid sinus massage (avoid in elderly or those with carotid disease)
   • Facial application of ice-cold wet towel
   • Head down deep breathing technique 3

2. Adenosine (Class I, Level B-R) 1

   • First-line pharmacological agent when vagal maneuvers fail
   • Highly effective (91% success rate) 1, 2
   • Acts as both diagnostic and therapeutic agent
   • Short half-life with rapid onset of action

3. Calcium Channel Blockers (Class IIa, Level B-R) 1

   • IV diltiazem or verapamil
   • Contraindicated in suspected pre-excited AF or VT
   • Similar efficacy to adenosine but longer half-life 4

4. Beta Blockers (Class IIa, Level B-R) 1

   • IV esmolol or metoprolol
   • Good safety profile but less effective than calcium channel blockers

5. Synchronized Cardioversion (Class I, Level B-NR) 1

   • For patients who fail pharmacological therapy
   • Immediate treatment for hemodynamically unstable patients

Long-term Management

Definitive Treatment

• Catheter Ablation (Class I, Level B-NR) 1, 2
  • Recommended for recurrent symptomatic PSVT
  • Success rates of 94-98%
  • Provides potential cure without need for chronic medications
  • Safe and highly effective as first-line therapy for prevention of recurrence 2

Pharmacological Prevention

• AV Nodal Blockers (Class I, Level B-R) 1

  • Oral beta blockers
  • Diltiazem or verapamil
  • For patients without ventricular pre-excitation

• Class IC Antiarrhythmics (Class IIa, Level B-R) 1

  • Flecainide and propafenone
  • Only for patients without structural heart disease or ischemic heart disease
  • Contraindicated in patients with structural heart disease or recent MI

• Ivabradine (Class IIa, Level B-R) 1

  • 2.5-7.5 mg twice daily
  • Reasonable for ongoing management

• Amiodarone 1

  • Reserved for short-term use or when alternatives aren't viable
  • Caution due to risk of thyroid disorders (13-36% in ACHD patients)

Special Considerations

Pregnancy

• Adenosine is safe due to short half-life 1
• Use lowest recommended medication doses
• Avoid medications in first trimester if possible

End-Stage Renal Disease

• Monitor for electrolyte abnormalities 1
• Be aware of dialysis-related fluid shifts triggering arrhythmias

Important Caveats and Pitfalls

• Do not attempt vagal maneuvers in hypotensive patients as they may worsen hemodynamic status 1
• Do not delay cardioversion to administer medications in hemodynamically unstable patients 1
• Avoid flecainide and propafenone in patients with structural heart disease due to proarrhythmic risk 1
• Monitor closely when administering IV amiodarone due to hypotension risk 1
• Calcium channel blockers are equally effective as adenosine but have a longer half-life and may be more cost-effective 4
• Adenosine has a higher probability of re-initiating arrhythmia compared to calcium channel blockers 4

Follow-up Care

• Refer patients to cardiology or electrophysiology within 1-2 weeks after initial presentation 1
• Educate patients on proper vagal maneuver techniques for home termination of episodes 1
• Monitor patients on medication therapy for side effects and efficacy 1