[1] Creighton Univ, Sch Med, Dept Med, Omaha, NE USA
[2] Univ Arkansas, Sch Med, Dept Med, Div Cardiovasc Med, Little Rock, AR USA
[3] Univ Connecticut, Sch Med, Dept Med, Farmington, CT USA
[4] East Carolina Brody Sch Med, Dept Med, Greenville, NC USA
[5] Univ Michigan, Sch Med, Dept Med, Sect Cardiovasc Med, Ann Arbor, MI USA
[6] Henry Ford Hosp, Dept Med, Sect Cardiovasc Med, Detroit, MI USA
[7] Harvard Med Sch, Brigham & Womens Hosp, Dept Med, Sect Cardiovasc Med, Boston, MA USA
[8] Inova Heart & Vasc Inst, Virginia Heart, Falls Church, VA USA
[9] Wake Forest Univ, Dept Med, Sch Med, Sect Cardiovasc Med, Winston Salem, NC 27109 USA