Management of Ventricular Tachycardia (V tach)
The management of ventricular tachycardia must be guided by hemodynamic stability, with immediate direct current cardioversion for unstable patients presenting with hypotension, altered mental status, or signs of shock. 1, 2
Initial Assessment and Management
Hemodynamic Stability Assessment
- Determine hemodynamic stability by assessing for hypotension, altered mental status, chest pain, heart failure, or shock 2
- Obtain a 12-lead ECG for all hemodynamically stable patients with sustained VT 2
- When diagnosis is unclear, presume wide-QRS tachycardia to be VT 2
Management of Hemodynamically Unstable VT
- Provide immediate synchronized direct current cardioversion (100 J for monomorphic VT with rates >150 bpm) 1
- Use unsynchronized discharge of 200 J for polymorphic VT that appears similar to VF 1
- For patients who are hypotensive but conscious, administer immediate sedation before cardioversion 1, 2
- Initiate CPR if the patient becomes unresponsive with no breathing or only occasional gasps 2
Management of Hemodynamically Stable VT
- Electrical cardioversion should be the first-line approach even in hemodynamically stable patients with monomorphic VT 2
- For pharmacological management, intravenous procainamide is recommended as first-line therapy for monomorphic VT, with monitoring of blood pressure and ECG 2
- Intravenous amiodarone (150 mg supplemental infusions mixed in 100 mL of D5W and infused over 10 minutes) is preferred in patients with heart failure or suspected myocardial ischemia 1, 2, 3
- For recurrent episodes after cardioversion, consider antiarrhythmic drug therapy to prevent acute reinitiation 1
Special Considerations
Medication Administration
- The recommended starting dose of amiodarone is approximately 1000 mg over the first 24 hours, followed by a maintenance infusion of 0.5 mg/min (720 mg per 24 hours) 3
- Do not exceed an initial amiodarone infusion rate of 30 mg/min to avoid hypotension 3
- Administer amiodarone through a central venous catheter when possible, especially for concentrations greater than 2 mg/mL 3
- Use an in-line filter during amiodarone administration 3
- For LV fascicular VT, intravenous verapamil or beta-blockers should be given 2
Common Pitfalls and Caveats
- Avoid calcium channel blockers (verapamil, diltiazem) in patients with VTach and structural heart disease as they may worsen hemodynamics or precipitate hemodynamic collapse 1
- Don't assume a wide-complex tachycardia is supraventricular - when in doubt, treat as VT 1
- Intravenous amiodarone concentrations greater than 3 mg/mL in D5W have been associated with a high incidence of peripheral vein phlebitis; use concentrations of 2.5 mg/mL or less for peripheral administration 3
- High concentration and rapid infusion rates of amiodarone can result in hepatocellular necrosis and acute renal failure 3
Long-term Management
Catheter Ablation Considerations
- Urgent catheter ablation is recommended in patients with scar-related heart disease presenting with incessant VT or electrical storm 1, 2
- Catheter ablation is recommended in patients with ischemic heart disease and recurrent ICD shocks due to sustained VT 1, 2
- Consider catheter ablation after a first episode of sustained VT in patients with ischemic heart disease and an ICD 1, 2
- For Purkinje-fiber triggered polymorphic VT refractory to drug treatment, catheter ablation may be considered 2
Post-Acute Management
- After converting VT to sinus rhythm, administer an antiarrhythmic infusion to prevent recurrence 4
- For patients with underlying heart disease and ventricular fibrillation or sustained symptomatic VT with hemodynamic compromise, an implantable cardioverter-defibrillator (ICD) is superior to antiarrhythmic drugs for improving overall survival 5
- For patients with sustained VT and a structurally normal heart (idiopathic VT), radiofrequency catheter ablation is a reasonable option 5
- Heart failure management in patients with reduced left ventricular function is crucial for long-term prognosis 6