Evaluation of amiodarone therapy in the treatment of drug-resistant cardiac arrhythmias: long term follow-up

Efficacy and safety of amiodarone in treatment of refractory atrial and ventricular tachyarrhythmias

The efficacy and the safety of amiodarone therapy in 82 patients with recurrent tachyarrhythmias, refractory to conventional antiarrhythmics, were evaluated by a multicenter trial. Clinical episodes of ventricular fibrillation, sustained and non-sustained ventricular tachycardia have been suppressed in 30 of 33, 45 of 50, and 40 of 46 patients, respectively, during a mean follow-up period of 8.3 months. There was no significant relation between QT prolongation and suppressive effects on recurrence of ventricular fibrillation, ventricular tachycardia and on frequency of ventricular premature beats. Recurrence of atrial fibrillation complicating hypertrophic cardiomyopathy has also been suppressed in seven of eight patients during a mean follow-up of 12 months. Adverse effects including thyroid dysfunction, corneal microdeposits, pulmonary abnormalities occurred in 65 percent of patients and treatment had to be discontinued in 15.9 percent. It was concluded that amiodarone is effective for long-term treatment of refractory atrial and ventricular tachyarrhythmias and that adverse effects are frequent but do not often limit treatment.