Thrombolytic therapy in acute myocardial infarction.

Thrombolytic therapy has revolutionized the treatment of acute myocardial infarction by reducing mortality and preserving left ventricular function. It is relatively safe and cost-effective. However, it is currently underused in most countries. Patients in whom thrombolysis is indicated include those with ST elevation on the electrocardiogram or bundle branch block pattern who present within 12 hours of myocardial infarction; the indications should be widened to include the elderly, patients who have undergone nontraumatic cardiopulmonary resuscitation, and women during menstruation. The risk-benefit ratio should be assessed for the individual patient. Prehospital thrombolytic treatment has been shown to be feasible with the support of well-trained staff and resuscitation equipment, and may be cost-effective in communities with time delays before hospitalization greater than 1 hour. The most important strategy is to shorten the "door to needle" time in hospital. The importance of full infarct-related artery flow (Thrombolysis in Myocardial Infarction [TIMI] grade 3 flow) for preservation of ventricular function and survival has been documented in the second Thrombolysis Trial of Eminase in Acute Myocardial Infarction (TEAM 2) and the Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO) studies. Aspirin and heparin are beneficial adjunctive regimens to thrombolytic therapy but optimal epicardial reperfusion is achieved in only about half of patients. Improved thrombolytic, adjunctive antiplatelet, and antithrombotic regimens are required to achieve early full reperfusion, which is crucial to improve survival and quality of life.