The Dartmouth Institute for Health Policy and Clinical Practice, Audrey and Theodor Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Department of Medicine, Audrey and Theodor Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Department of Community and Family Medicine, Audrey and Theodor Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire. Electronic address: jbrown@dartmouth.edu. The Dartmouth Institute for Health Policy and Clinical Practice, Audrey and Theodor Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire. The Dartmouth Institute for Health Policy and Clinical Practice, Audrey and Theodor Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Department of Medicine, Audrey and Theodor Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; Department of Community and Family Medicine, Audrey and Theodor Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire. Department of Cardiology, Virgen Macarena University Hospital, Seville, Spain. Hospital São Lucas, PUCRS, Porto Alegre, Rio Grande do Sul, Brazil. Department of Cardiology, Odense University Hospital, Odense, Denmark. Department of Cardiology, University Hospital Basel, Petersgraben, Switzerland. Division of Cardiology, Misericordia e Dolce Hospital, Prato, Italy. Fletcher Allen Health Care, University of Vermont School of Medicine, Burlington, Vermont.