Empiric therapy with beta-blockers.

The only class of drugs with significant effects on ventricular fibrillation and sudden death in humans is that of beta-blockers. The exact mechanisms for these prophylactic effects are not known but may be related to both antiischemic or antiarrhythmic influences. It seems reasonable to suggest that one should use a beta-blocker with proven effect on total mortality and sudden cardiac death after myocardial infarction as prophylaxis. Therefore, propranolol, timolol, or metoprolol, should be instituted in order to improve prognosis when there are no contraindications. In addition to possible effects on survival one would also expect to reduce the risk for new ischemic events with angina or reinfarction. In contrast, class I antiarrhythmic agents are useful for symptomatic ventricular arrhythmias but there is no proof for any effect on ventricular fibrillation and sudden cardiac death.