The antiarrhythmic properties of
amiodarone at the ventricular level were discovered in the early 1970s. The unanimously recognised efficacy of
amiodarone includes a weak negative inotropic effect and compensatory vasodilatory properties, making
amiodarone particularly suitable for treating the potentially malignant arrhythmias associated with organic disease. In a review of 611 hospitalised patients on
amiodarone, and 353 patients in whom the
drug had been prescribed, over a 52-month period in our 60-bed department, we noted that
amiodarone was prescribed in 53% of patients for arrhythmias and in 47% of patients for coronary insufficiency. Ventricular arrhythmias represented 13% of the rhythmic indications. These indications differ from those in the USA. The efficacy (70 to 90%) of
amiodarone in
ventricular extrasystoles has been shown in open studies. In coronary patients, the antiarrhythmic activity of
amiodarone is superior to that of
propranolol. However, there has been no controlled study because the need for a loading dosage, and the electrocardiographic effects render such studies difficult. After
myocardial infarction, ventricular arrhythmias constitute a significant risk factor independently of prognosis;
amiodarone may be useful in this indication, and studies of the European
Myocardial Infarction Amiodarone Trial (EMIAT) type will examine its value here. Since 1973, it has been recognised that
amiodarone can prevent
ventricular tachycardia in 55 to 89% of patients in the clinical situation. After a long-standing controversy, the positive predictive value of programmed stimulation has finally been agreed on. In
hypertrophic cardiomyopathy, retrospective studies suggest a reduction in mortality in patients treated with
amiodarone. By contrast, the value of
amiodarone in
dilated cardiomyopathy requires more intensive investigation. We consider
amiodarone to be indicated in ventricular arrhythmic complexes, particularly if they are associated with an ejection fraction of less than 35% and/or
atrial fibrillation. The value of
amiodarone in arrhythmias associated with
heart failure needs to be evaluated. In conclusion,
amiodarone is a powerful antiarrhythmic agent but, because of the possibility of dose- and duration-dependent side effects, evaluation of the risk: benefit ratio in each indication is needed.