What is the treatment for ventricular tachycardia?

Treatment of Ventricular Tachycardia

For hemodynamically unstable VT (hypotension, altered mental status, chest pain, heart failure, or heart rate ≥150 bpm), perform immediate synchronized DC cardioversion starting at 100J, escalating to 200J then 360J if needed; for hemodynamically stable monomorphic VT, procainamide is the first-line pharmacological agent at 10 mg/kg IV over 10-20 minutes. 1, 2, 3

Initial Assessment: Determine Hemodynamic Stability

The critical first step is determining whether the patient is hemodynamically stable or unstable. 2

Unstable VT is defined by:

• Hypotension (systolic BP ≤90 mmHg) 4
• Altered mental status or loss of consciousness 5
• Chest pain or acute heart failure 4, 2
• Heart rate ≥150 beats/min 4, 2

For pulseless VT: Follow the VF protocol with immediate unsynchronized defibrillation—this is cardiac arrest. 4, 2

Treatment Algorithm for Hemodynamically Unstable VT

Immediate synchronized DC cardioversion is mandatory without delay. 1, 2, 3

• Start with 100J synchronized shock, escalate to 200J, then 360J if unsuccessful 4, 2
• For polymorphic VT resembling VF, use unsynchronized 200J discharge 3
• Sedate the conscious but unstable patient immediately before cardioversion 1, 2
• If VT recurs after cardioversion, administer antiarrhythmic drugs to prevent reinitiation 3

Treatment Algorithm for Hemodynamically Stable Monomorphic VT

First-Line: Procainamide

Procainamide is the preferred first-line agent for stable monomorphic VT, demonstrating the greatest efficacy among antiarrhythmics. 1, 2, 6

• Dosing: 10 mg/kg IV at 50-100 mg/min over 10-20 minutes (maximum dose 10-20 mg/kg) 1, 2, 7
• Monitor continuously for hypotension and QRS widening during administration 2
• Stop infusion if hypotension develops or QRS widens >50% from baseline 2
• Procainamide is FDA-indicated for documented life-threatening ventricular arrhythmias including sustained VT 7

Important caveat: Avoid procainamide in patients with severe heart failure or acute myocardial infarction—use amiodarone instead. 1

Alternative Agents When Procainamide is Contraindicated

Amiodarone is preferred in patients with heart failure or suspected ischemia:

• Dosing: 150 mg (5 mg/kg) IV over 10 minutes, then 1 mg/min infusion for 6 hours, then 0.5 mg/min 8
• FDA-indicated for hemodynamically unstable VT and frequently recurring VF 8
• Reduces life-threatening arrhythmias, required shocks, and symptomatic VT episodes 1
• Major limitation: Antiarrhythmic effect may take up to 30 minutes, making it less suitable for urgent situations 4, 2

Sotalol may be considered for stable monomorphic VT:

• Can be used in patients with acute myocardial infarction 1
• Exercise caution due to significant beta-sympatholytic properties 9
• Requires QTc monitoring—do not initiate if baseline QTc >450 ms 10

Lidocaine is notably less effective:

• Only moderately effective and inferior to procainamide, sotalol, or amiodarone 1, 2
• Despite being historically popular, current evidence does not support it as first-line therapy 6, 9

Special Considerations for Polymorphic VT

For polymorphic VT with normal QT interval (likely ischemia-related):

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

For polymorphic VT with prolonged QT (Torsades de Pointes):

• IV magnesium sulfate: 8 mmol bolus followed by 2.5 mmol/h infusion 4, 2
• Correct electrolyte abnormalities (potassium, magnesium) 1
• Consider overdrive pacing 2
• Avoid: Isoproterenol in familial long QT syndrome 2

Critical Pitfalls to Avoid

Never assume wide-complex tachycardia is supraventricular—when in doubt, treat as VT. 3

Avoid calcium channel blockers (verapamil, diltiazem) in VT with structural heart disease:

• These agents may precipitate hemodynamic collapse and worsen outcomes 4, 3
• Only safe in fascicular VT, which is rare 3

Do not administer multiple sequential antiarrhythmic drugs:

• If one agent fails to terminate VT, proceed directly to electrical cardioversion rather than trying additional medications 9
• Multiple drug administration increases proarrhythmic risk 9

Long-Term Management Considerations

After acute stabilization:

• Beta-blockers are the cornerstone for catecholaminergic polymorphic VT 1, 2
• Consider ICD implantation for secondary prevention in structural heart disease 2
• Urgent catheter ablation is recommended for incessant VT or electrical storm in scar-related heart disease 1, 3
• Catheter ablation should be considered for recurrent ICD shocks due to sustained VT in ischemic heart disease 1, 3

Monitoring Requirements

For all VT treatment:

• Continuous ECG monitoring is mandatory 1
• Measure and normalize serum potassium and magnesium before initiating antiarrhythmics 1
• Monitor QTc interval—discontinue drug if QTc prolongs to ≥500 ms 1
• Facility must have cardiac resuscitation capabilities immediately available 4, 1