1. Division of Cardiovascular Medicine; University of Utah; Salt Lake City Utah
2. Department of Medicine; University of Massachusetts Medical School; Worcester Massachusetts
3. Department of Medicine; University of Utah; Salt Lake City Utah
4. Division of Cardiovascular Medicine; Temple University School of Medicine; Philadelphia Pennsylvania
5. Division of Cardiovascular Medicine; University of Arkansas for Medical Sciences; Little Rock Arkansas
6. Cardiovascular Division; Hospital of the University of Pennsylvania; Philadelphia Pennsylvania
7. Division of Cardiothoracic Surgery; Emory University School of Medicine; Atlanta Georgia
8. Clinical Research Unit, Division of Cardiology; Emory University School of Medicine; Atlanta Georgia
9. Division of Cardiovascular Medicine; Texas Tech University Health Sciences Center; El Paso Texas