[1] Univ Hosp Giessen, Dept Internal Med 2, Pulm Hypertens Div, Giessen, Germany
[2] Massachusetts Gen Hosp, Pulm & Crit Care, Boston, MA 02114 USA
[3] Univ Hosp Gasthuisberg, Dept Pneumol, Leuven, Belgium
[4] Univ Bologna, Inst Cardiol, Bologna, Italy
[5] Charles Univ Prague, Clin Dept Cardiol & Angiol, Fac Med 1, Dept Med 2, Prague, Czech Republic
[6] Actel Pharmaceut Ltd, Allschwil, Switzerland
[7] Univ Western Ontario, Dept Med, Div Respirol, London Hlth Sci Ctr, London, ON, Canada
[8] Natl Inst Cardiol, Cardiopulm Dept, Mexico City, DF, Mexico
[9] CARE Hosp, Dept Cardiol, Hyderabad, Andhra Pradesh, India
[10] Univ Paris 11, CHU Bicetre, Le Kremlin Bicetre, France
[11] Univ Sao Paulo, Sch Med, Inst Heart, Dept Pulm, Sao Paulo, Brazil
[12] ECZ Otwock, Dept Pulm Circulat & Thromboembol Dis, Ctr Postgrad Med Educ, Otwock, Poland
[13] Univ Calif San Diego, Div Pulm & Crit Care Med, San Diego, CA 92103 USA