[1] Med Univ South Carolina, Dept Neurol, Charleston, SC USA
[2] Med Univ South Carolina, Dept Pediat, Charleston, SC USA
[3] Duke Clin Res Inst, Durham, NC USA
[4] Mayo Clin, Dept Hlth Sci Res, Rochester, MN USA
[5] Duke Univ, Med Ctr, Dept Neurol, Durham, NC USA
[6] Univ Calif Los Angeles, Div Cardiol, Los Angeles, CA USA
[7] Univ Calgary, Hotchkiss Brain Inst, Calgary, AB T2N 1N4, Canada
[8] Massachusetts Gen Hosp, Dept Neurol, Boston, MA 02114 USA
[9] Harvard Med Sch, Boston, MA USA