1 Department of Internal Medicine, University of Maryland Medical Center, MD, United States.
2 Heart Rhythm Services, Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, United States.
3 Department of Pediatric and Adolescent Medicine, Division of Pediatric Cardiology, Mayo Clinic, Rochester, MN, United States.
4 Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Osaka, Japan.
5 Heart Rhythm Services, Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, United States. Electronic address: Mcleod.christopher@mayo.edu.