[1] Northwestern Univ, Sch Med, Div Cardiol, Chicago, IL 60611 USA
[2] Duke Clin Res Inst, Durham, NC USA
[3] Univ N Carolina, Heart Failure Program, Chapel Hill, NC USA
[4] Univ Alabama Birmingham, Birmingham, AL USA
[5] Boston Univ, Sch Med, Boston, MA 02118 USA
[6] Vet Affairs Med Ctr, San Francisco, CA 94121 USA
[7] Univ Hosp Cleveland, Cleveland, OH 44106 USA
[8] EHS Christ Hosp & Med Ctr, Oak Lawn, IL USA