Do you use synchronized cardioversion for ventricular tachycardia (Vt)?

Synchronized Cardioversion for Ventricular Tachycardia

Yes, synchronized cardioversion is the first-line treatment for hemodynamically unstable ventricular tachycardia (VT) and is also recommended for hemodynamically stable VT when pharmacological therapy is ineffective or contraindicated. 1

Approach to VT Management Based on Hemodynamic Status

Hemodynamically Unstable VT

• Immediate synchronized cardioversion is the treatment of choice
• Signs of hemodynamic instability include:
  • Hypotension
  • Acutely altered mental status
  • Signs of shock
  • Chest pain
  • Acute heart failure symptoms

Hemodynamically Stable VT

1. First attempt: Pharmacological therapy

   • Procainamide: Most efficacious (10 mg/kg at 50-100 mg/min IV over 10-20 min) 2
   • Amiodarone: Alternative option, especially for patients with structural heart disease 3
   • Lidocaine: Less effective (converts only about 20% of stable VTs) 4
   • Sotalol: Higher conversion rate (approximately 70%) 4

2. If pharmacological therapy fails: Synchronized cardioversion 2

   • Performed after adequate sedation or anesthesia
   • Highly effective in terminating VT

Special Considerations

Refractory VT

• For VT refractory to standard cardioversion, consider:
  • Double sequential synchronized cardioversion - may be effective without requiring additional medications that could worsen hypotension 5
  • Intravenous amiodarone - effective for unstable, recurrent VT that is resistant to lidocaine or procainamide 4

Energy Settings

• Low energy synchronized shocks (0.025 to 2.0 joules) may be effective for some VT episodes 6
• Higher energy settings are typically used in clinical practice

Pitfalls to Avoid

• Delay in cardioversion for unstable patients: Do not delay electrical cardioversion to attempt pharmacological conversion in hemodynamically unstable patients
• Unsynchronized shock: Ensure synchronization is activated for VT with a pulse to avoid delivering shock during the vulnerable period of cardiac cycle
• Inappropriate medication selection: Avoid calcium channel blockers like verapamil or diltiazem for VT as they may cause hemodynamic collapse 7
• Failure to prepare for deterioration: Always be prepared for VT to deteriorate into ventricular fibrillation, which requires immediate defibrillation (unsynchronized shock)

Long-term Management After Acute Conversion

• Consider implantable cardioverter-defibrillator (ICD) for secondary prevention of sudden cardiac death 1
• Beta-blockers and/or amiodarone for primary prevention of recurrent episodes 1
• Evaluate for underlying structural heart disease or ischemia

Synchronized cardioversion remains a cornerstone of VT management, particularly in unstable patients, and should be readily available in the emergency setting.