[1] Univ Cincinnati, Med Ctr, 1001 Holmes Bldg,200 Albert Sabin Way, Cincinnati, OH 45267 USA
[2] INOVA Med Ctr, Fairfax, VA USA
[3] Royal Hosp Brompton, London, England
[4] King Saud Univ, Dept Med, Div Pulm Med, Riyadh, Saudi Arabia
[5] Cleveland Clin, Cleveland, OH 44106 USA
[6] Univ Alabama Birmingham, Birmingham, AL USA
[7] Temple Univ, Philadelphia, PA 19122 USA
[8] Mayo Clin, Rochester, MN USA
[9] Univ Utah, Salt Lake City, UT USA
[10] Erasmus Univ, Med Ctr, Dept Resp Med, Rotterdam, Netherlands
[11] Univ Southern Calif, Los Angeles, CA USA
[12] Kings Coll London, London, England
[13] Christ Hosp, Cincinnati, OH 45219 USA