Treatment of Ventricular Tachycardia with Amiodarone

From the Guidelines

Amiodarone is the preferred treatment for ventricular tachycardia (VT) that is unresponsive to initial shocks or has recurred after initial treatment.

Key Points

• The initial dose of amiodarone for VT is 300 mg IV, which can be followed by an additional dose of 150 mg IV if necessary 1.
• Amiodarone can be administered as an infusion, with a rate of 1 mg/min for 6 hours, followed by 0.5 mg/min 1.
• The maximum dose of amiodarone per 24 hours is 2.2 g IV 1.
• Amiodarone has been shown to be effective in preventing recurrent monomorphic VT or treating refractory ventricular arrhythmias in patients with coronary artery disease and poor ventricular function 1.
• The use of amiodarone may be associated with adverse effects such as hypotension, bradycardia, and AV block, but these effects can be minimized with careful dosing and monitoring 1.

Indications and Contraindications

• Amiodarone is indicated for the treatment of VT, including monomorphic and polymorphic VT, as well as ventricular fibrillation (VF) 1.
• Contraindications to amiodarone use include conditions associated with QT interval prolongation, inherited long QT syndrome, sinus bradycardia, and severe AV conduction disturbances 1.

Comparison to Other Antiarrhythmic Agents

• Amiodarone has been shown to be more effective than lidocaine in terminating VT and preventing recurrent arrhythmias 1.
• Amiodarone may be considered as an alternative to other antiarrhythmic agents, such as procainamide and sotalol, in certain situations 1.

From the FDA Drug Label

Amiodarone hydrochloride injection is an antiarrhythmic agent indicated for initiation of treatment and prophylaxis of frequently recurring ventricular fibrillation (VF) and hemodynamically unstable ventricular tachycardia (VT) in patients refractory to other therapy Amiodarone hydrochloride injection is indicated for initiation of treatment and prophylaxis of frequently recurring ventricular fibrillation (VF) and hemodynamically unstable ventricular tachycardia (VT) in patients refractory to other therapy.

Treatment of Ventricular Tachycardia with Amiodarone:

• Amiodarone is indicated for the treatment of hemodynamically unstable ventricular tachycardia (VT) in patients refractory to other therapy 2 2.
• The recommended starting dose is about 1000 mg over the first 24 hours of therapy, delivered by a specific infusion regimen 2.
• For breakthrough episodes of VF or hemodynamically unstable VT, repeat the initial load of 150 mg in 100 mL (in D5W) infused over 10 minutes 2.

From the Research

Treatment of Ventricular Tachycardia with Amiodarone

• Amiodarone is a commonly used anti-arrhythmic drug for the treatment of ventricular tachycardia (VT) and ventricular fibrillation (VF) 3, 4, 5.
• The drug has been shown to be effective in controlling hemodynamically stable VT, polymorphic VT, and wide-complex tachycardia of uncertain origin 3.
• Amiodarone is also used for ventricular rate control of rapid atrial arrhythmias in patients with severely impaired left ventricular function 3.

Efficacy and Safety

• Studies have demonstrated the efficacy of amiodarone in treating VT and VF, with response rates ranging from 64% to 71% 4, 5.
• However, amiodarone has been associated with significant adverse effects, including hypotension, bradycardia, peripheral phlebitis, pulmonary toxicity, and blue skin discoloration 3, 4, 5.
• The risk of adverse effects warrants careful surveillance during treatment with amiodarone 4.

Comparison with Other Anti-Arrhythmic Drugs

• A randomized study compared the safety and efficacy of intravenous procainamide and amiodarone for the acute treatment of tolerated wide QRS tachycardia, and found that procainamide was associated with fewer major cardiac adverse events and a higher proportion of tachycardia termination within 40 minutes 6.
• Another study found that amiodarone did not prevent induction of sustained ventricular tachycardia in any of the patients inducible at baseline, and may have facilitated inducibility of sustained ventricular arrhythmias 7.

Dosage and Administration

• The dosage of amiodarone varies depending on the patient and the specific condition being treated, but typical doses range from 200 to 600 mg/day for long-term treatment 3, 4.
• Intravenous amiodarone has been used for the acute treatment of ventricular tachyarrhythmias, with doses ranging from 5 to 10 mg/kg 7, 6.