The American journal of cardiology
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Review Randomized Controlled Trial Comparative Study Clinical Trial
Advantages of beta blockers versus antiarrhythmic agents and calcium antagonists in secondary prevention after myocardial infarction.
Patients who have sustained greater than or equal to 1 myocardial infarcts are at high risk for sudden death or reinfarction; the risk is highest for those with lowest ventricular ejection fraction, continuing myocardial ischemia and asymptomatic high-density and complex premature ventricular contractions. At present, beta blockers when given prophylactically are the only agents that reduce the incidence of sudden death and reinfarction in survivors of myocardial infarction (MI) in the first 2 years. The beneficial effect was shown to correlate with a reduction in heart rate, the effect being absent or deleterious with beta blockers with marked sympathomimetic activity. ⋯ Whether these data can be extrapolated to all class I agents is uncertain. Preliminary data with class III antiarrhythmic agents suggest that these agents, especially amiodarone, similarly to beta blockers, have the potential to reduce mortality in survivors of MI. Evolving data suggest that in the secondary prevention of morbid events in the survivors of acute MI, the focus must shift away from antiarrhythmic agents that delay conduction and toward beta blockers and antifibrillatory actions resulting from a prolongation of refractoriness.