Multicenter Unsustained Tachycardia Trial (MUSTT)

BACKGROUND:

Cardiac arrest (sudden cardiac death) occurs relatively frequently in asymptomatic patients who have had myocardial infarctions, have ejection fractions less than 40 percent, and non-sustained ventricular tachycardia. However, it is not possible to predict who will die suddenly or when cardiac arrest will occur. Current efforts to reduce sudden death in such long-term survivors of myocardial infarction or in patients with coronary disease have produced results that are not very encouraging.

Such patients may feel quite well. They survived their myocardial infarction and may have slight or even moderate reduction of exercise ability, but by 'pacing' themselves, such patients can lead relatively normal lives. They may be aware of their arrhythmia because of short periods of palpitations which may only trouble them transiently. Consequently, this group of patients, many still in the prime of their lives, are at relatively high risk of dying suddenly.

The multicenter trial may reveal the most effective treatment for such patients, the value of electrophysiologic studies in predicting who is most at risk of sudden cardiac death, and whether electrophysiologic studies can help select the best mode of treatment. The protocol for performing programmed stimulation and serial drug testing is designed to mirror those currently in use by many practicing electrophysiologists.

DESIGN NARRATIVE: