Role of beta-adrenergic blockade in the therapy of patients with myocardial infarction.
Beta-adrenergic blockade appears to have beneficial effects on ischemic myocardium, both in experimental animals and in patients. There is substantial evidence that beta blockade, when induced promptly after coronary occlusion, is capable of limiting the size of experimentally produced infarcts. Although many mechanisms of action have been proposed, the bulk of available evidence suggests that beta blockade reduces the severity of myocardial ischemia by reducing myocardial oxygen demands. Intravenous and oral therapy with beta-blockers is safe when patients are carefully selected and observed. Invasive hemodynamic monitoring is not usually necessary for safe use of these drugs. Preliminary reports based on studies with several beta-blockers indicate that early intervention might limit infarct size or even prevent its occurrence, particularly in patients with evidence of increased sympathetic activity. However, before early beta blockade can be recommended as standard therapy for uncomplicated myocardial infarction, these findings should be confirmed in rigorously controlled clinical trials utilizing several techniques for assessment of infarct size. The most significant finding with beta-blockers in patients with myocardial infarction has been that these drugs can improve survival when administered to patients on a long-term basis after infarction. Although the mechanism of this protective effect is not yet understood, the results are clear enough to warrant the routine administration of a beta-blocker to patients who have had infarction and who have no contraindications to such therapy.
D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D004285:Dogs; D004562:Electrocardiography; D006321:Heart / Q000187:drug effects; D006801:Humans; D009203:Myocardial Infarction / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D009206:Myocardium / Q000473:pathology; D051381:Rats
D000319:Adrenergic beta-Antagonists