['Cardiac ballet' with and without amiodarone]

Abstract

Two well documented cases of torsades de pointes under amiodarone therapy are discussed. This special form of ventricular tachycardia is also known as "twisting around the points" or "cardiac ballet". Our first case involves recurrent torsades de pointes manifesting almost 2 weeks following onset of amiodarone therapy. They were successfully treated by overpacing. In the second case the isolated torsade de pointes was probably not caused by the longlasting and successful use of amiodarone but reflected severe ischemic heart disease and slight hypokalemia. This was confirmed in the one year follow-up, as torsade de pointes was no longer present despite increased dosage of amiodarone. Amiodarone-induced torsades de pointes is very rare. Most cases reported in the literature are poorly documented or were caused by other factors (electrolyte disturbances, other antiarrhythmic medication). If amiodarone has been administered as a matter of utmost necessity, other etiologies must be excluded or eliminated before amiodarone therapy is stopped when torsades de pointes occurs. Torsade de pointes due to amiodarone arises independently of the duration of therapy, the administered dosage and the extent of QT-prolongation. Holter monitoring does not allow a prediction and the benefit of electrophysiological studies is still controversial. The management of patients with amiodarone-induced torsades de pointes includes administration of magnesium and, frequently, overpacing. Due to the long half-life of amiodarone, prolonged temporary pacing may be required. General experience suggested that amiodarone can be used safely in patients who have developed torsades de pointes with other agents.