[1] Univ Pittsburgh, Sch Med, Dept Cardiothorac Surg, Div Cardiac Surg, Pittsburgh, PA USA
[2] West Virginia Univ, Dept Cardiovasc & Thorac Surg, Morgantown, WV USA
[3] Duke Clin Res Inst, Durham, NC USA
[4] Emory Univ, Sch Med, Div Cardiothorac Surg, Dept Surg, Atlanta, GA 30322 USA
[5] Georgetown Univ, Dept Cardiac Surg, Medstar Washington Hosp Ctr, Washington, DC USA
[6] Johns Hopkins All Childrens Heart Inst, Div Cardiovasc Surg, St Petersburg, FL USA