1. Division of Cardiology (M.A.A., S.K., R.V., D.P., P.T.E., S.A.L.), Department of Medicine, Massachusetts General Hospital, Boston, MA.
2. Cardiovascular Research Center (M.A.A., S.K., X.W., R.V., D.P., P.T.E., S.A.L.), Department of Medicine, Massachusetts General Hospital, Boston, MA.
3. Cardiovascular Disease Initiative, Broad Institute of Harvard and the Massachusetts Institute of Technology, Cambridge, MA (M.A.A., S.K., X.W., R.V., P.T.E., S.A.L.).
4. Demoulas Center for Cardiac Arrhythmias (S.K., P.T.E., S.A.L.), Department of Medicine, Massachusetts General Hospital, Boston, MA.
5. Division of General Internal Medicine (J.M.A., D.E.S., S.J.A.), Department of Medicine, Massachusetts General Hospital, Boston, MA.
6. Department of Medicine, Harvard Medical School, Boston, MA (D.E.S., S.J.A.).