Use of amiodarone in the postmyocardial infarction patient.

Amiodarone appears to be an effective antiarrhythmic agent for reducing mortality in the postmyocardial infarction patient with ventricular ectopic activity. Such activity has long been recognized to have an adverse effect on prognosis after acute myocardial infarction. When a strong correlation between ectopic activity and left ventricular dysfunction was demonstrated, ventricular ectopic activity was thought to be a consequence of underlying myocardial damage. However, ventricular ectopic activity is now considered to be an independent risk factor for mortality after myocardial infarction. Because of the basic premise that a positive correlation existed between arrhythmia suppression and improved survival, it had been common practice to use antiarrhythmic agents to treat asymptomatic ventricular ectopic activity in the postinfarction patient. After the results of the Cardiac Arrhythmia Suppression Trial (CAST) were released, this practice was largely abandoned. In the post-CAST era, however, amiodarone has appeared to improve survival in patients who have sustained myocardial infarctions. In this report, we briefly review the pharmacology of amiodarone and discuss the results of relevant clinical trials. Large, multicenter trials currently under way may clarify some of the unanswered questions surrounding the use of this promising antiarrhythmic agent in postmyocardial infarction patients.