1 Section of Cardiovascular Medicine, Department of Medicine, Boston Medical Center, Boston University Chobanian and Avedisian School of Medicine, Boston, Massachusetts, USA.
2 New York Institute of Technology College of Osteopathic Medicine, New York, New York, USA.
3 Division of Cardiovascular Medicine and Department of Obstetrics and Gynecology, Department of Medicine, University of Southern California, Los Angeles, California, USA.