Prof. (Dr.) Young Keun On graduated from the College of Medicine, Seoul National University, Seoul, Korea, in 1991. The clinical training includes an internal medicine residency and cardiology fellowship. He was a doc visiting scholar at the Krannert Institute of Cardiology, Indiana University, from 2008 to 2009. He is currently a Professor of the Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine. Prof. On is an active clinical cardiac electrophysiologist. He is a member of the Korean Society of Circulation, the Korea Heart Rhythm Society, and the Heart Rhythm Society. Also, he is a Fellow of the Heart Rhythm Society.