[The patient at risk of sudden death:value of drug therapy]

The evaluation of antiarrhythmic therapy should be based on its effects on total mortality assessed by controlled trials. The author reviews the large trials on antiarrhythmic drugs, during the past ten years, and concludes with the current importance of such therapy. Trials have been conducted in three kinds of high-risk populations: patients with malignant ventricular arrhythmias, survivors of myocardial infarction and patients with congestive heart failure. The results have been disappointing, showing either an increase in mortality with antiarrhythmic drugs (class I, d-sotalol) or a neutral effect (amiodarone). Trials conducted in patients with malignant arrhythmias have shown that the implantable cardioverter-defibrillator was superior to the best available antiarrhythmic therapy. In other high-risk populations, the only drugs that consistently reduced mortality were betablockers, which might have other mechanisms of action besides the antiarrhythmic effect. Amiodarone, the most potent suppressor of ventricular arrhythmias, is indicated in highly symptomatic patients; dl-sotalol is a good alternative to amiodarone. We may conclude from these large trials that study endpoints must be correctly chosen in order to assess the real value of an antiarrhythmic drug. The study population must have a high risk of sudden death and be within an appropriate time window of maximal risk. Antiarrhythmic trials must proceed, learning the lessons from the old studies, trying to test new drugs or new therapeutic strategies, better selecting study populations and new risk markers superior to those currently available.