What is the treatment for ventricular tachycardia (VT)?

Treatment for Ventricular Tachycardia

The treatment for ventricular tachycardia (VT) requires immediate electrical cardioversion for hemodynamically unstable patients, while procainamide is the first-line pharmacological treatment for stable monomorphic VT without severe heart failure or acute myocardial infarction. 1

Initial Assessment and Classification

Treatment approach depends on:

1. Hemodynamic stability:

   • Unstable: Hypotension, altered mental status, chest pain, heart failure
   • Stable: Normal blood pressure, alert, no significant symptoms

2. VT morphology:

   • Monomorphic: Regular QRS complexes of similar shape
   • Polymorphic: Irregular QRS complexes with changing morphology

Treatment Algorithm

Hemodynamically Unstable VT

1. Immediate synchronized cardioversion (100J, 200J, then 360J) 1
2. If pulseless VT develops:
   • Begin high-quality CPR
   • Defibrillate (unsynchronized shock)
   • Follow ACLS protocol for cardiac arrest

Hemodynamically Stable Monomorphic VT

1. First-line medication: Procainamide

   • Dose: 10 mg/kg IV at 50-100 mg/min over 10-20 minutes
   • Monitor blood pressure and ECG during administration 1, 2
   • Contraindicated in severe heart failure or acute MI

2. Alternative medications:

   • Amiodarone: For patients with heart failure or acute MI
     • Initial dose: 150 mg IV over 10 minutes
     • Followed by: 1 mg/min for 6 hours, then 0.5 mg/min 1, 3
   • Sotalol: Alternative for stable monomorphic VT
     • Use with caution due to beta-blocking properties 1

3. If medications fail: Proceed to synchronized cardioversion 1

Polymorphic VT

Treatment depends on QT interval during sinus rhythm:

1. With long QT (Torsades de Pointes):

   • Stop QT-prolonging medications
   • Correct electrolyte abnormalities
   • IV magnesium
   • Consider pacing or isoproterenol if bradycardia present 4

2. Without long QT (most commonly due to ischemia):

   • IV amiodarone
   • Beta-blockers 4, 1

Prevention of Recurrence

1. Pharmacological therapy:

   • Amiodarone reduces recurrent episodes 4, 1
   • Beta-blockers improve survival and reduce recurrent arrhythmias 1

2. Device therapy:

   • ICD implantation for prevention of sudden cardiac death in patients with documented sustained VT 1

3. Catheter ablation:

   • Consider for scar-related VT, incessant VT, electrical storm, or recurrent ICD shocks 1

Special Considerations

• Acute myocardial infarction: Amiodarone preferred over procainamide 1
• Severe heart failure: Avoid procainamide; use amiodarone 4
• Polymorphic VT with familial long QT: Use IV magnesium, pacing, and/or beta-blockers; avoid isoproterenol 4

Pitfalls to Avoid

• Delaying cardioversion in unstable patients
• Using lidocaine as first-line therapy (less effective than other options) 1
• Overlooking underlying causes of VT (ischemia, electrolyte abnormalities, drug toxicity)
• Failure to monitor for hypotension and QT prolongation during antiarrhythmic administration
• Neglecting long-term management after acute stabilization

Remember that while pharmacological therapy can be effective for acute management, many patients will require definitive treatment with ICD implantation or catheter ablation to prevent recurrence and improve long-term outcomes.