To the Editor.
—The article by the Cardiology Working Group1 raises issues relevant to the decision making of cardiologists and is both searching and appropriate. Missing, however, is the exclusion of a major contemporary issue that has a significant effect on the economics of treating acute myocardial infarction. I refer specifically to the widespread use, almost exclusively in the United States, of recombinant tissue plasminogen activator (rTPA), as the primary thrombolytic agent of choice. Clinical trials of over 66 000 patients in hospitals around the world indicate that there is no benefit of rTPA when compared with streptokinase. The report of the International Study of Infarct Survival-3 (ISIS-3) at the 40th Annual Meeting of the American College of Cardiology in Atlanta, Ga, further supports this conclusion (New York Times National Edition. March 4, 1991:B9). The 5-week mortality in ISIS-3 of 46 092 patients with suspected or definite acute myocardial