[1] Hosp Ramon & Cajal, Resp Dept, IRYCIS, E-28034 Madrid, Spain
[2] Univ Gottingen, Dept Cardiol & Pulmonol, Gottingen, Germany
[3] Hosp Ramon & Cajal, Dept Med, IRYCIS, E-28034 Madrid, Spain
[4] Hosp Ramon & Cajal, Dept Cardiol, IRYCIS, E-28034 Madrid, Spain
[5] Univ Hosp Bern, Div Gen Internal Med, CH-3010 Bern, Switzerland
[6] Uniformed Serv Univ Hlth Sci, F Edward Hebert Sch Med, Bethesda, MD 20814 USA
[7] Washington Univ, Sch Med, Div Pulm & Crit Care Med, St Louis, MO USA
[8] Washington Univ, Sch Med, Div Gen Med Sci, St Louis, MO USA
[9] Democritus Univ Thrace, Dept Cardiol, Alexandroupolis, Greece