1. Division of Cardiac Surgery, Queen's University, Kingston, ON Canada
2. Division of Cardiac Surgery, University of Brescia Medical School, Brescia, Italy
3. Division of Cardiac Surgery, University of Milan, Milan, Italy
4. Division of Cardiology, University of Milan, Milan, Italy
5. Division of Cardiology, University of Brescia Medical School, Brescia, Italy
6. Division of Cardiovascular Surgery, CHU Bordeaux Hopital Haut-Leveque, Bordeaux, France.