Eugene H Blackstone1, Tara B Karamlou2. 1. Department of Thoracic and Cardiovascular Surgery, Heart and Vascular Institute, Cleveland Clinic, Cleveland, Ohio; Department of Quantitative Health Sciences, Research Institute, Cleveland Clinic, Cleveland, Ohio. Electronic address: blackse@ccf.org. 2. Department of Thoracic and Cardiovascular Surgery, Phoenix Children's Heart Center, Phoenix, Ariz.