What is the treatment for ventricular tachycardia (VTach)?

Treatment of Ventricular Tachycardia

For hemodynamically unstable VT, perform immediate synchronized cardioversion starting at 100J, escalating to 200J then 360J; for hemodynamically stable monomorphic VT, procainamide is the first-line pharmacological agent with the greatest efficacy among antiarrhythmics. 1, 2, 3

Initial Assessment: Determine Hemodynamic Stability

The critical first step is determining whether the patient is hemodynamically unstable, defined by any of the following 1, 2:

• Systolic blood pressure ≤90 mmHg 4, 2
• Chest pain or acute heart failure 1, 2
• Heart rate ≥150 beats/min 4, 1
• Altered mental status or signs of shock 1

If the patient has no pulse, this is pulseless VT—follow the VF protocol with immediate unsynchronized defibrillation. 4, 2

Treatment Algorithm for Hemodynamically Unstable VT

Immediate synchronized DC cardioversion is the definitive treatment without delay. 1, 2, 5

Cardioversion Protocol:

• Start with 100J synchronized shock 4, 2
• If unsuccessful, escalate to 200J 4, 2
• If still unsuccessful, escalate to 360J 4, 2
• Sedate the conscious but unstable patient immediately before cardioversion 1, 2

Post-Cardioversion Management:

• If VT recurs after successful cardioversion, administer antiarrhythmic drugs to prevent reinitiation 2
• Amiodarone is indicated for prophylaxis of frequently recurring VF and hemodynamically unstable VT refractory to other therapy 6

Treatment Algorithm for Hemodynamically Stable Monomorphic VT

Procainamide is the preferred first-line pharmacological agent, demonstrating the greatest efficacy among all antiarrhythmics for stable monomorphic VT. 1, 2, 3

Procainamide Administration:

• Dose: 10-20 mg/kg IV at 50-100 mg/min over 10-20 minutes 1, 2, 3
• Monitor continuously for hypotension and QRS widening during administration 1, 2
• Stop infusion if QRS widens by >50% or hypotension develops 2
• Procainamide is FDA-approved for documented life-threatening ventricular arrhythmias such as sustained VT 7

Contraindications to Procainamide:

Avoid procainamide in patients with severe heart failure or acute myocardial infarction—use amiodarone instead. 2

Alternative Pharmacological Agents

Amiodarone (When Procainamide is Contraindicated):

Amiodarone is preferred in patients with heart failure or suspected ischemia. 2, 5

• Loading dose: 150 mg (5 mg/kg) IV over 10 minutes 2, 6
• Maintenance infusion: 1 mg/min for 6 hours, then 0.5 mg/min 2, 6
• For breakthrough VF or hemodynamically unstable VT, repeat the 150 mg bolus 6
• Amiodarone reduces life-threatening arrhythmias, required shocks, and symptomatic VT episodes 2, 5
• Critical caveat: Amiodarone's antiarrhythmic effect may take up to 30 minutes, making it less suitable for emergent situations. 4, 1

Sotalol:

• May be considered for stable monomorphic VT, including patients with acute MI 5
• Exercise caution due to significant beta-sympatholytic properties 2

Lidocaine:

Lidocaine is only moderately effective and less effective than procainamide, sotalol, or amiodarone. 5, 3

• Dose: 1-3 mg/kg IV (100 mg bolus for cardiac arrest), may repeat after 5-10 minutes 4
• Maintenance infusion: 2-4 mg/min 4

Special Considerations for Polymorphic VT

Polymorphic VT with Normal QT Interval (Likely Ischemia-Related):

• Consider IV beta-blockers 1, 2
• Treat underlying ischemia aggressively 2

Polymorphic VT with Prolonged QT (Torsades de Pointes):

Administer IV magnesium sulfate: 8 mmol bolus followed by 2.5 mmol/h infusion. 4, 1, 2

• Correct electrolyte abnormalities (potassium, magnesium) 2
• Magnesium is particularly effective for VF/VT associated with acute MI 4

Catecholaminergic Polymorphic VT:

Beta-blockers are the cornerstone of treatment. 1, 5

• For recurrent sustained VT or syncope despite beta-blockers, consider combination therapy with flecainide, left cardiac sympathetic denervation, and/or ICD 5

Critical Pitfalls to Avoid

Never assume wide-complex tachycardia is supraventricular—when in doubt, treat as VT. 2

Avoid calcium channel blockers (verapamil, diltiazem) in VT with structural heart disease, as they may precipitate hemodynamic collapse and worsen outcomes. 4, 2

• These agents are only appropriate for SVT, not VT 4
• They can cause accelerated ventricular rate leading to ventricular fibrillation in VT 4

Monitoring Requirements During Treatment

• Continuous ECG monitoring is mandatory for all VT treatment 2
• Measure and normalize serum potassium and magnesium before initiating antiarrhythmics 2
• Monitor QTc interval—discontinue drug if QTc prolongs to ≥500 ms 2
• Facility must have cardiac resuscitation capabilities immediately available 2

Long-Term Management After Acute Stabilization

ICD Implantation:

• Consider ICD for secondary prevention in patients with structural heart disease 1, 5
• ICD is superior to antiarrhythmic drugs for improving overall survival in patients with sustained symptomatic VT with hemodynamic compromise 8

Catheter Ablation:

• Urgent catheter ablation is recommended for incessant VT or electrical storm in scar-related heart disease 2, 5
• Catheter ablation is recommended in patients with ischemic heart disease and recurrent ICD shocks due to sustained VT 5
• For idiopathic VT in structurally normal hearts, radiofrequency catheter ablation is a reasonable option 8

Beta-Blocker Therapy:

• Beta-blockers may be useful for preventing recurrence in refractory ventricular tachyarrhythmias 5
• Essential for catecholaminergic polymorphic VT 1, 5