[1] Duke Univ, Med Ctr, Durham, NC USA
[2] Duke Clin Res Inst, Durham, NC 27715 USA
[3] Univ Alberta, Edmonton, AB, Canada
[4] Oslo Univ Hosp, Oslo, Norway
[5] Univ Calif San Francisco, San Francisco, CA 94143 USA
[6] San Francisco VA Med Ctr, San Francisco, CA USA
[7] Cleveland Clin, Cleveland, OH 44106 USA
[8] Kardiol Klin, Wroclaw, Poland