[1] Creighton Univ, Div Cardiol, Sch Med, Omaha, NE 68124 USA
[2] Rochester Reg Hlth Unity Hosp, Rochester, NY USA
[3] Univ Kentucky, Dept Med, Lexington, KY USA
[4] Iowa Heart Ctr, Div Cardiovasc Med, Des Moines, IA USA
[5] Univ Nebraska, Div Cardiovasc Med, Med Ctr, Omaha, NE USA
[6] MedStar Washington Hosp Ctr, Sect Intervent Cardiol, Washington, DC USA
[7] Keele Univ, Keele Cardiovasc Res Grp, Keele, England