1 Division of Cardiovascular Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, Pa. Electronic address: benjamin.smood@pennmedicine.upenn.edu.
2 Division of Cardiac, Thoracic and Vascular Surgery, Department of Surgery, New York Presbyterian/Columbia University Medical Center, New York City, NY. Electronic address: sn2859@cumc.columbia.edu.
3 Division of Cardiovascular Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, Pa.