1. Division of Cardiology, Brigham and Women’s Hospital, Tower 3B, 75 Francis Street, Boston, MA 02115.
2. Decision Systems Group, Department of Radiology, Brigham andWomen’s Hospital, Boston, Massachusetts
3. Department of Nuclear Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts
4. Decision Systems Group, Department of Radiology, Brigham and Women’s Hospital, Boston, Massachusetts