Determination of the potential value of thrombolytic therapy in patients with acute myocardial infarction was an issue of major importance in 1983. An estimated 1.4 million heart attacks occurred each year, of which over 500,000 were fatal. Reduction of mortality required an effective means to reduce infarct size. Studies indicated that reperfusion represented a potent means of achieving salvage of ischemic myocardium. Pilot clinical studies indicated that reperfusion could be achieved in a substantial percentage of patients by lysis of coronary thrombosis with both intracoronary and intravenous streptokinase administration. Intracoronary thrombolysis was receiving widespread clinical applications but had many limitations. The intracoronary route took 90-120 minutes longer to administer than the intravenous route. Because intracoronary therapy required the availability of a catheterization laboratories and highly skilled invasive cardiologists, this treatment was not available to large numbers of patients who were hospitalized in smaller community hospitals.