oice with a loading dose of 150 mg i.v bolus given during 10 minutes. An infusion at 1 mg/min during 6 hours, followed by 0.5 mg/min during 18 hours is also started. The loading dose may be repeated with 15 minute intervals. Maximum dose amiodarone is 2.2 g/day. If amiodarone fails, one should consider electrical cardioversion before considering pharmacological alternatives. Lidocaine is given as iv bolus of 0.75 mg/kg which can be repeated after 5–10 minutes. Infusion lidocaine 1–4 mg/min (maximum dose 3 mg/kg/h) is started simultaneously.
Digoxin induced ventricular tachycardia may be treated as a hemodynamically stable patients above. Note that there are antibodies against digoxin.
Transcutaneous or transvenous pacing: Pacing at higher frequency than the ventricular tachycardia may terminate it (but there is a risk of degeneration into ventricular fibrillation).
Intermittent ventricular tachycardia with frequent capture beats should be treated pharmacologically.
Polymorphic ventricular tachycardia should be considered unstable and treated immediately with electrical cardioversion. Beta-blockers may be administered if the ECG does not show long QT interval. If the ECG does show long QT interval, the condition is classified as torsade de pointes; refer to this article for treatment recommendations. Amiodarone may also be administered if there is no evidence of long QT interval.
Bradycardia induced ventricular tachycardia (sinus bradycardia, AV-block etc): Bradycardia may induce premature ventricular complexes and ventricular arrhythmias. These are treated with atropine, isoproterenol (isoprenaline) or transvenous pacing.
Long-term treatment of ventricular tachycardia
Patients with preserved left ventricular function and asymptomatic non-sustained ventricular tachycardias may be adequately treated with beta-blockers. Sotalol (may cause QT prolongation) and amiodarone may also be considered. Verapamil is contraindicated. If the individual has suffered a myocardial infarction, an ICD should be considered.
Patients with high risk of sudden cardiact arrest (reduced left ventricular function, previous myocardial infarction, structural heart disease) should be considered for an ICD which offers effective protection. Otherwise, amiodarone appears to be the most effective drug in preventing new episodes of ventricular tachycardia.