1. UPMC Heart and Vascular Institute and Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, USA
2. Department of Cardiothoracic Surgery, UC Davis Medical Center, Sacramento, CA, USA
3. Department of Cardiovascular Surgery, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
4. Department of Cardiac Surgery, Na Homolce Hospital, Prague, Czech Republic
5. Department of Cardiac Surgery, Main Line Health - Lankenau Heart Institute, Wynnewood, PA, USA
6. Division of Cardiac Surgery, University of Toronto, St. Michael’s Hospital, Toronto, ON, Canada
7. Division of Cardiac Surgery, Thomas Jefferson University, Philadelphia, PA, USA