What is the treatment for ventricular tachycardia?

Treatment for Ventricular Tachycardia

For hemodynamically unstable VT (hypotension, altered mental status, shock, syncope), perform immediate synchronized direct current cardioversion without delay—sedating conscious patients first—starting at 100J for monomorphic VT and 200J unsynchronized for polymorphic VT. 1, 2, 3

Acute Management Algorithm

Step 1: Assess Hemodynamic Stability

Unstable VT is defined by:

• Hypotension
• Altered mental status or syncope
• Signs of shock
• Heart rate ≥150 beats/min 3

Stable VT means the patient is conscious, normotensive, and tolerating the rhythm 1, 3

Step 2: Immediate Treatment Based on Stability

For Hemodynamically Unstable VT:

• Perform immediate synchronized DC cardioversion starting at 100J, escalating to 200J then 360J if needed 2, 3
• If the patient is hypotensive but conscious, give immediate sedation before cardioversion 1, 2
• For polymorphic VT resembling VF, use unsynchronized discharge of 200J 2
• For pulseless VT, follow VF protocol with immediate defibrillation 3

For Hemodynamically Stable Monomorphic VT:

Procainamide is the first-line pharmacological agent 1, 3, 4, 5:

• Dose: 10-20 mg/kg IV at 50-100 mg/min over 10-20 minutes 1, 3
• Monitor continuously for hypotension and QRS widening during administration 3
• Procainamide demonstrates the greatest efficacy among antiarrhythmic drugs 5

Alternative agents if procainamide is unavailable or contraindicated:

• Amiodarone is preferred in patients with heart failure or suspected myocardial ischemia 1, 2, 6:

  • Can reduce life-threatening arrhythmias, required shocks, and symptomatic sustained VT episodes 1
  • Antiarrhythmic effect may take up to 30 minutes, making it less suitable for emergent situations 3
  • FDA-approved for frequently recurring VF and hemodynamically unstable VT refractory to other therapy 6

• Sotalol may be considered for hemodynamically stable sustained monomorphic VT, including acute MI patients 1, 7:

  • Must check baseline QTc—do not initiate if QTc >450 ms 7
  • Reduce dose or discontinue if QTc prolongs to ≥500 ms 7

• Lidocaine is only moderately effective and less effective than procainamide, sotalol, or amiodarone 1, 3

Step 3: Special VT Subtypes

Polymorphic VT with Normal QT:

• Consider IV beta-blockers if ischemia-related 3

Polymorphic VT with Long QT (Torsades de Pointes):

• IV magnesium: 8 mmol bolus followed by 2.5 mmol/h infusion 3
• Pacing and beta-blockers for familial long QT syndrome 3
• Avoid isoproterenol in familial long QT 3

Catecholaminergic Polymorphic VT:

• Beta-blockers are the cornerstone of treatment 1, 3
• For recurrent VT despite beta-blockers, consider combination therapy with flecainide, left cardiac sympathetic denervation, and/or ICD 1

Step 4: Long-Term Management

Catheter ablation is recommended for:

• Patients with scar-related heart disease presenting with incessant VT or electrical storm (urgent ablation) 1, 2
• Ischemic heart disease patients with recurrent ICD shocks due to sustained VT 1, 2
• After first episode of sustained VT in ischemic heart disease patients with an ICD 1
• Purkinje-fiber triggered polymorphic VT refractory to drug treatment 1

ICD implantation should be considered for secondary prevention in patients with structural heart disease 3

Critical Pitfalls to Avoid

• Never use calcium channel blockers (verapamil, diltiazem) in VT with structural heart disease—they may precipitate hemodynamic collapse 2
• Only use calcium channel blockers if you are certain the rhythm is fascicular VT 2
• When in doubt about wide-complex tachycardia, treat as VT rather than assuming supraventricular origin 2
• If VT recurs after cardioversion, add antiarrhythmic drug therapy to prevent acute reinitiation 2
• For patients with an ICD, place defibrillator patches at least 8 cm from the generator position 1
• Most post-MI VT/VF occurs within 48 hours; sustained VT/VF outside this timeframe requires careful evaluation including possible electrophysiology studies 2