Safety and Cost-Effectiveness of Early Discharge After Primary Angioplasty in Low Risk Patients With Acute Myocardial Infarction 11Research funding for this study was provided by unrestricted grants from Advanced Cardiovascular Systems, Santa Clara, California; Mallinckrodt Medical, Inc., Saint Louis, Missouri; Datascope Corporation, Montvale, New Jersey; St. Jude Medical, Chelmsford, Massachusetts; and Siemens Corporation, Iselin, New Jersey.