1. From the Vascular Biology Group, Department of Biomedical Science (J.v.d.H., K.H., T.A.J.), University of Copenhagen, Denmark
2. Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine (R.W.M., G.W.A.).
3. Cardiac Electrophysiology Group, Department of Biomedical Science (M.B.T.), University of Copenhagen, Denmark