1 Department of Cardiothoracic and Vascular Surgery, University of Texas Health Science Center Houston, McGovern Medical School, Houston, TX, USA.
2 Department of Surgery, San Antonio Military Medical Center, Fort Sam Houston, TX, USA.
3 Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine and Texas Heart Institute at CHI Baylor St. Luke's Medical Center, Houston, TX, USA.
4 Division of Cardiothoracic Surgery, New York Presbyterian Hospital-College of Physicians and Surgeons of Columbia University, New York, NY, USA.