What is the algorithm for managing ventricular tachycardia (VTach)?

Algorithm for Managing Ventricular Tachycardia

The first step in managing ventricular tachycardia is to assess hemodynamic stability, with immediate synchronized cardioversion recommended for patients presenting with hemodynamically unstable VT. 1

Initial Assessment and Management

Step 1: Assess Hemodynamic Stability

• Unstable VT signs: Hypotension, altered mental status, signs of shock, severe chest pain
• Stable VT signs: Normal blood pressure, alert and oriented, no signs of end-organ hypoperfusion

Step 2: Management Based on Stability

For Hemodynamically Unstable VT:

1. Immediate synchronized cardioversion (Class I recommendation) 1

   • Sedate if patient is conscious but proceed without delay
   • Start with 100J (synchronized)
   • Increase energy as needed if initial shock fails

2. After successful cardioversion:

   • Consider IV antiarrhythmic to prevent recurrence
   • Amiodarone 150mg IV over 10 minutes (can repeat to maximum 2.2g/24 hours) 1, 2

For Hemodynamically Stable Monomorphic VT:

1. 12-lead ECG to confirm diagnosis 1

   • Look for:
     • QRS width >0.14s with RBBB or >0.16s with LBBB pattern
     • VA dissociation (pathognomonic for VT)
     • Fusion beats or QR complexes (indicate VT)

2. Pharmacological cardioversion options:

   • First choice: IV Procainamide (Class IIa recommendation) 1, 3

     • Dosage: 10 mg/kg at 50-100 mg/min IV over 10-20 minutes
     • Monitor BP and ECG during administration
     • Contraindicated in patients with severe heart failure or prolonged QT

   • Alternative: IV Amiodarone (Class IIb recommendation) 1, 2

     • Dosage: 150 mg IV over 10 minutes
     • Can repeat as needed to maximum 2.2g/24 hours
     • Particularly useful in patients with heart failure or ischemia

   • Other options:

     • Sotalol 1.5 mg/kg IV over 5 minutes (avoid in prolonged QT) 1
     • Lidocaine (less effective than other options) 1

3. If pharmacological cardioversion fails:

   • Proceed to synchronized electrical cardioversion (Class I recommendation) 1
   • Provide appropriate sedation
   • Start with 100J, increase as needed

Long-term Management

For Patients with Scar-Related VT:

1. Urgent catheter ablation is recommended for patients with:

   • Incessant VT
   • Electrical storm
   • Recurrent ICD shocks due to sustained VT (Class I recommendation) 1

2. Catheter ablation should be considered after first episode of sustained VT in patients with ischemic heart disease and ICD (Class IIa recommendation) 1

Important Considerations:

• Even "stable" VT is associated with high mortality and should be treated aggressively 4
• Electrophysiology consultation should be obtained early in the management
• Pre-excitation syndromes can mimic VT - careful ECG interpretation is essential 1
• Monitor for hypotension during antiarrhythmic administration, especially with amiodarone 1

Special Situations

Polymorphic VT:

• Often associated with acute myocardial ischemia, channelopathies, or ventricular hypertrophy
• May require different management approach including addressing underlying cause
• Some cases may be amenable to Purkinje-fiber targeted catheter ablation 1

VT with Acute Coronary Syndrome:

• Urgent coronary revascularization may be necessary
• Amiodarone preferred over procainamide due to less negative inotropic effect 1

Remember that even stable VT is associated with significant mortality risk and should be treated promptly and aggressively to prevent deterioration to ventricular fibrillation 4.