Amiodarone for Refractory Supraventricular Tachycardias

Emmertsen K, Bjerregaard P, Andreasen F (Department of Cardiology, Aarhus Kommunehospital and Institute of Pharmacology, University of Aarhus, Aarhus, Denmark). Amiodarone for refractory supraventricular tachycardias. Acta Med Scand 1987; 221:435–9. Amiodarone was administered to 53 patients with otherwise drug‐refractory supraventricular tachycardias. Therapy was effective in 35 patients and partially effective in nine patients for a median duration of 35 months. The median maintenance dose was 200 mg/day in both groups, whereas the median serum amiodarone concentrations were 1.1 mg/l and 0.7 mg/l, respectively. Amiodarone was ineffective in nine patients despite higher dosage (median 400 mg/day) and insignificantly higher serum concentrations (median 2.0 mg/l). Neither the age of the patients, the duration or type of arrhythmia, the cardio‐thoracic index, nor the type of underlying heart disease were predictive of the efficacy of amiodarone. Side‐effects occurred in 28 patients, leading to withdrawal of therapy in 12 patients. Side‐effects were not associated with higher serum amiodarone concentrations. Despite its efficacy, amiodarone should be reserved for otherwise drug‐resistant supraventricular tachyarrhythmias.