What is the treatment for ventricular tachycardia (VTach)?

Treatment for Ventricular Tachycardia

The treatment for ventricular tachycardia (VT) depends primarily on hemodynamic stability, with immediate electrical cardioversion being the first-line treatment for hemodynamically unstable VT, while pharmacological therapy is appropriate for stable VT, with procainamide being the preferred first-line medication for stable monomorphic VT without severe heart failure or acute myocardial infarction. 1

Initial Assessment and Hemodynamic Stability

• Determine hemodynamic stability - VT is considered unstable if the patient has hypotension, chest pain, heart failure, or a heart rate ≥150 beats/min 2
• For hemodynamically unstable VT, immediate electrical cardioversion is indicated without delay 2, 1
• For pulseless VT, follow the VF protocol with immediate defibrillation 2

Treatment Algorithm for Ventricular Tachycardia

Hemodynamically Unstable VT

• Provide immediate synchronized DC cardioversion starting at 100J, increasing to 200J and then 360J if needed 2
• Sedate the patient before cardioversion if conscious but unstable 1
• After successful cardioversion, consider antiarrhythmic drugs to prevent recurrence 3

Hemodynamically Stable Monomorphic VT

1. First-line pharmacological treatment:

   • Procainamide: 10-20 mg/kg IV at 50-100 mg/min over 10-20 minutes 1, 4
   • Monitor for hypotension and QRS widening during administration 2

2. Alternative medications if procainamide is unavailable or contraindicated:

   • Amiodarone: 150 mg IV over 10 minutes, followed by 1.0 mg/min for 6 hours, then 0.5 mg/min maintenance 2, 5
   • Lidocaine: 1-1.5 mg/kg IV bolus, with supplemental boluses of 0.5-0.75 mg/kg every 5-10 minutes to maximum 3 mg/kg, followed by infusion of 2-4 mg/min 2
   • Sotalol: May be considered for hemodynamically stable sustained monomorphic VT, including patients with AMI 2, 6

3. If pharmacological treatment fails:

   • Proceed to synchronized electrical cardioversion 4, 7

Special Considerations for Specific Types of VT

• Polymorphic VT with normal QT interval:

  • Consider IV beta-blockers if ischemia-related 2, 1
  • Consider isoproterenol for catecholaminergic VT 2

• Polymorphic VT with long QT syndrome:

  • IV magnesium (8 mmol bolus followed by 2.5 mmol/h infusion) 2
  • Pacing and beta-blockers for familial long QT syndrome 2
  • Avoid isoproterenol in familial long QT syndrome 2

• Polymorphic VT with acquired long QT syndrome:

  • IV magnesium 2
  • Consider pacing or isoproterenol if associated with bradycardia 2

Long-term Management After Acute Episode

• Evaluate for underlying cardiac disease and treat accordingly 8
• Consider ICD implantation for secondary prevention in patients with structural heart disease 3
• Catheter ablation may be indicated for recurrent VT, especially in patients with ischemic heart disease 1
• Beta-blockers are the cornerstone of treatment for catecholaminergic polymorphic VT 1

Common Pitfalls and Caveats

• Lidocaine is less effective than procainamide, sotalol, or amiodarone for stable VT 1, 4
• Amiodarone's antiarrhythmic effect may take up to 30 minutes, making it less suitable for emergent situations 2
• Patients with VT during acute myocardial infarction have higher mortality and require more aggressive management 7
• Approximately half of stable VT patients treated with amiodarone will convert to sinus rhythm under paramedic care 9
• Prolonged episodes of VT may lead to hemodynamic and metabolic decompensation, so early termination is warranted 8