1. From the Departments of Cardiology (I.K., P.v.d.H., L.v.G., W.H.v.G., D.J.v.V., R.A.d.B.) and Nephrology (G.N.), University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; and the IVth Division of Internal Medicine (F.M.), San Vito Hospital, Torino, Italy.