What are the management options for Paroxysmal Supraventricular Tachycardia (PSVT)?

Management of Paroxysmal Supraventricular Tachycardia (PSVT)

Catheter ablation is the most effective first-line therapy for preventing recurrent PSVT, with success rates of 94-98%, providing a potential cure without the need for chronic medications. 1, 2, 3

Acute Management Algorithm

Hemodynamically Unstable Patients

• Synchronized cardioversion is the immediate treatment of choice 1, 2
• Do not delay cardioversion to administer medications 2

Hemodynamically Stable Patients

1. First-line: Vagal maneuvers (Class I, Level B-R) 1, 2

   • Success rate approximately 27.7% 2
   • Techniques:
     • Modified Valsalva maneuver (most effective at 43%) 3
     • Perform in supine position 1
     • Forcefully exhale against closed airway for 10-30 seconds (30-40 mmHg) 1
     • Apply ice-cold wet towel to face (diving reflex) 1
     • Novel technique: quickly lying backward from seated position 4

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

   • High success rate (91%) 2, 3
   • Acts as both diagnostic and therapeutic agent 2

3. Third-line options if adenosine fails or is contraindicated:

   • Calcium channel blockers: IV diltiazem or verapamil (Class IIa, Level B-R) 1, 2
     • Verapamil: 2.5-5 mg IV bolus over 2 minutes (3 minutes in older patients)
     • Can repeat 5-10 mg every 15-30 minutes to maximum 20 mg 2
   • Beta blockers: IV metoprolol or esmolol (Class IIa, Level C-LD) 1, 2

4. Fourth-line: Synchronized cardioversion for stable patients when medications fail (Class I, Level B-NR) 1, 2

Long-term Management Options

1. Catheter Ablation (First-line)

• Recommended as first-line therapy for recurrent symptomatic PSVT (Class I, Level B-NR) 1, 2, 3, 5
• High success rates (94-98%) 2, 3
• Provides potential cure without chronic medications 1
• Refer to cardiology/electrophysiology within 1-2 weeks after initial presentation 2

2. Pharmacological Management (If ablation not preferred/available)

First-line pharmacological options:

• Oral beta blockers, diltiazem, or verapamil (Class I, Level B-R) 1, 2
  • Effective for ongoing management in patients without pre-excitation 1
  • Well-tolerated with documented reduction in episode frequency 1

Second-line pharmacological options:

• Flecainide or propafenone (Class IIa, Level B-R) 1, 6, 7
  • Reasonable for patients without structural heart disease 1
  • Flecainide: 100-300 mg/day 1
  • Propafenone: 450-900 mg/day 1
  • Contraindicated in structural heart disease or ischemic heart disease 1, 2, 6

Third-line pharmacological options:

• Sotalol (Class IIb, Level B-R) 1

  • May be reasonable when other options fail 1
  • Can be used in patients with structural heart disease (unlike flecainide/propafenone) 1

• Dofetilide (Class IIb, Level B-R) 1

  • May be reasonable when other options are ineffective or contraindicated 1

• Amiodarone (Class IIb, Level C-LD) 1, 2

  • Consider only when other options fail 1
  • Caution due to risk of thyroid disorders (13-36%) 2

Special Considerations

Contraindications and Cautions

• Avoid dihydropyridine CCBs (including nifedipine) for SVT treatment (Class III: Harm) 2
• Avoid verapamil/diltiazem in patients with:
  • Pre-excited atrial fibrillation
  • Significant LV dysfunction
  • Risk for cardiogenic shock
  • PR interval >0.24 seconds
  • Second or third-degree AV block without pacemaker 2
• Avoid combining calcium channel blockers with other AV nodal blocking agents due to risk of profound bradycardia 2
• Monitor for hypotension with rapid administration of calcium channel blockers 2

Patient Education

• Teach proper vagal maneuver techniques for home use 1, 2
• Explain warning signs requiring medical attention 2
• For infrequent, well-tolerated episodes, consider "pill-in-the-pocket" approach 2

By following this management algorithm, clinicians can effectively treat both acute episodes and provide long-term management for patients with PSVT, with catheter ablation offering the best chance for definitive cure in appropriate candidates.