1 From Department of Medicine, The Johns Hopkins University, Baltimore, MD (T.M.M.); and Division of Cardiology, Section for Cardiac Electrophysiology, Hospital of the University of Pennsylvania, Philadelphia (S.N.).
2 From Department of Medicine, The Johns Hopkins University, Baltimore, MD (T.M.M.); and Division of Cardiology, Section for Cardiac Electrophysiology, Hospital of the University of Pennsylvania, Philadelphia (S.N.). saman.nazarian@uphs.upenn.edu.