1. From the Departments of Physiology (L.v.H., N.H., M.L.H., I.F-P., R.J.M., A.B., J.v.d.V., G.J.M.S., W.J.P.), Cardiology (J.G.F.B.), Endocrinology (M.D.), and Pathology and Surgery (K.K, H.W.M.N.), Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, the Netherlands; Department of Cardiology (A.J.J.I, G.J.L.), Onze Lieve Vrouwe Gasthuis, Amsterdam, the Netherlands; and Department of Internal Medicine (C.G.S.), University of Maastricht, Maastricht, the Netherlands.