The Data Monitoring Experience in the Cardiac Arrhythmia Suppression Trial: The Need to Be Prepared Early

Abstract

The Cardiac Arrhythmia Suppression Trial (CAST) was designed to evaluate the hypothesis that suppression of cardiac ventricular arrhythmias in patients with a recent myocardial infarction would reduce the incidence of sudden death and total mortality, using three drugs known to suppress cardiac arrhythmias. Patients were randomized to receive either active drug or a matching placebo. The trial was terminated after only 15% of the planned-for events had been observed with an unexpected but dramatic increase in sudden death and total mortality in those patients receiving two of the active therapies. Later, the third drug was also discontinued.