1 Department of Medicine, Stanford University School of Medicine, Menlo Park, California.
2 Quantitative Sciences Unit, Department of Medicine, Stanford University School of Medicine, Menlo Park, California.
3 Department of Medicine, Stanford University School of Medicine, Menlo Park, California; Cardiovascular Division, Department of Medicine, Stanford University School of Medicine, Menlo Park, California; Cardiovascular Institute, Stanford University, Stanford, California.
4 Department of Medicine, Stanford University School of Medicine, Menlo Park, California; Cardiovascular Division, Department of Medicine, Stanford University School of Medicine, Menlo Park, California; Cardiovascular Institute, Stanford University, Stanford, California. Electronic address: [email protected].