1. From the Department of Pulmonology (Y.W., G.R., A.B., A.V.-N.), the Department of Physiology (Y.Y.W., G.R., A.B., N.W., W.J.v.d.L), the Department of Nuclear Medicine and PET Research (M.L., P.G.R., A.A.L.), the Department of Cardiology (P.K.), and the Department of Physics and Medical Technology (J.T.M.), Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands.