1. Division of Cardiology, Duke University, Durham, North Carolina2Duke Clinical Research Institute, Durham, North Carolina
2. Duke Clinical Research Institute, Durham, North Carolina
3. Division of Cardiology, Veterans Affairs Puget Sound Health System and the University of Washington, Seattle
4. Division of Cardiology, University of California, Davis, Sacramento
5. Division of Cardiology, Mid-America Heart Institute, Kansas City, Kansas
6. Division of Cardiology, University of Texas–Southwestern, Dallas