[1] Mayo Clin, Div Thorac, Coll Med, 200 First St SW, Rochester, MN 55905 USA
[2] Mayo Clin, Div Cardiovasc Radiol, Coll Med, 200 First St SW, Rochester, MN 55905 USA
[3] Univ Kentucky, Div Cardiovasc & Thorac Radiol, UK HealthCare Imaging Informat, Radiol Informat & Integrated Clin Operat, 800 Rose St,HX 302, Lexington, KY 40536 USA