1. Division of Cardiology, Columbia University Medical Center, New York, New York
2. Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, Connecticut
3. Respiratory Department, Hospital Ramón y Cajal, Madrid, Spain
4. Hospital Universitari Germans Trias i Pujol, Badalona, Spain
5. Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, Massachusetts