Thrombolytic therapy has been proven to be highly effective and safe in patients presenting with acute myocardial infarction. Its use may reduce mortality rates by as much as 50%. Accelerated administration of tissue plasminogen activator (Activase) combined with intravenous heparin shows particular success in reducing mortality rates, especially in patients with anterior infarcts. However, strict compliance to the classic inclusion criteria has limited the number of patients, excluding several groups who have been shown to benefit from thrombolysis: The elderly appear to benefit from early thrombolysis even more than do their younger counterparts. Patients with inferior myocardial infarction and bundle-branch blocks also benefit. Recent trials suggest that thrombolytic therapy can be cautiously extended to patients presenting late (up to 24 hours) after onset of symptoms. Certain patients with a history of cerebrovascular disease or recent surgery, patients with severe hypertension, and those having undergone cardiopulmonary resuscitation should not necessarily be excluded from consideration.