Treatment for Ventricular Tachycardia Storm
The most effective treatment for ventricular tachycardia (VT) storm is immediate administration of intravenous amiodarone combined with beta-blockers, with hemodynamically unstable patients requiring immediate synchronized cardioversion. 1
Initial Assessment and Management
- For unstable VT with pulse but hypotension (systolic BP ≤90 mmHg), perform immediate synchronized DC cardioversion starting at 100J, then 200J, then 360J as needed with appropriate sedation if the patient is conscious 2, 1
- For hemodynamically stable patients experiencing VT storm, initiate pharmacological management immediately 1
Pharmacological Management
First-Line Therapy
- Administer intravenous amiodarone at 150 mg infused over 10 minutes, followed by a constant infusion of 1.0 mg/min for 6 hours, then maintenance at 0.5 mg/min 1, 3
- Combine amiodarone with intravenous beta-blockers, which are considered the single most effective therapy for polymorphic VT storm 1
- For breakthrough episodes of VF or hemodynamically unstable VT, use 150 mg supplemental infusions of amiodarone (mixed in 100 mL of D5W and infused over 10 minutes) 3
Alternative Agents
- Lidocaine can be used as an alternative or in addition to amiodarone, particularly when VT is thought to be related to myocardial ischemia 1
- Procainamide is another alternative agent, with a loading infusion of 20-30 mg/min up to 12-17 mg/kg, followed by infusion of 1-4 mg/min 4, 1
Advanced Management for Refractory VT Storm
- Consider overdrive pacing for patients with frequently recurring or incessant VT 1
- General anesthesia may be beneficial for patients with frequently recurring or incessant VT 1
- Spinal cord modulation can be considered for some patients with refractory VT storm 1
- For drug-refractory polymorphic VT, implement aggressive measures to reduce myocardial ischemia, including beta-blockade, intra-aortic balloon pumping, and emergency PTCA/CABG surgery 4
Important Considerations and Precautions
- Amiodarone shows considerable interindividual variation in response, requiring close monitoring with dose adjustment 3
- Do not exceed an initial infusion rate of 30 mg/min to avoid hypotension 3
- For infusions longer than 1 hour, do not exceed amiodarone concentrations of 2 mg/mL unless a central venous catheter is used, as higher concentrations are associated with peripheral vein phlebitis 3
- Monitor for side effects of intravenous amiodarone, including hypotension and bradycardia, which can be managed by reducing the infusion rate 5
- Reduce amiodarone infusion rates in older patients and those with heart failure or hepatic dysfunction to avoid toxicity 3
- Correct electrolyte abnormalities, particularly potassium and magnesium, which can contribute to arrhythmias 2
Addressing Underlying Causes
- Aggressively treat heart failure in patients with left ventricular dysfunction 1
- Aggressively treat myocardial ischemia, which is a common trigger for VT storm 1
- Consider coronary revascularization when there is clear evidence of acute myocardial ischemia preceding ventricular fibrillation 1
Evidence of Effectiveness
- Clinical studies have demonstrated that high-dose amiodarone (approximately 1000 mg over 24 hours) is more effective than low-dose therapy (approximately 125 mg over 24 hours) in suppressing recurrent VF or hemodynamically unstable VT 3
- In comparative studies, amiodarone has shown superior efficacy to lidocaine for the treatment of shock-resistant VT, with a 78% immediate VT termination rate for amiodarone versus 27% for lidocaine 6
- Long-term management with amiodarone and beta-blockers has shown effectiveness in preventing recurrence of VT storm, with one case report demonstrating successful control using the combination of propranolol and amiodarone after failure of metoprolol and amiodarone 7