Medical therapy of acute myocardial infarction: Part II. The role of adjunctive medical therapy.

The second part of this review summarizes the role of other classes of pharmacological therapy in treatment of acute myocardial infarction (MI). The goals of pharmacological therapy are to alleviate symptoms, to stabilize hemodynamic status, and to prevent arrhythmias. These agents have been utilized primarily because of their ability to limit infarct size. Other beneficial properties may include their effects on neurohormonal activation, hemodynamics, and arrhythmias. In an individual patient, age, associated medical conditions, and hemodynamic status are important considerations in choosing a specific class of drug therapy. The beta-adrenergic blocking agents have modest effects on mortality, and they are useful when used alone and in combination with thrombolytic agents. Calcium antagonists have a limited role in acute MI. Diltiazem reduces the incidence of reinfarction in patients with non-Q MI. Oral nitrate therapy has not been shown to reduce mortality. Data from recent trials suggest that prophylactic administration of antiarrhthymic therapy is also not useful in acute MI. The role of angiotensin-converting enzyme inhibitors when administered in the acute phase of MI needs to be evaluated further. These agents are safe and well tolerated, and they offer greatest benefit when given in patients with left ventricular dysfunction.