1. From the Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (R.F., B.M.W.I., I.B., C.H.G.)
2. Department of Internal Medicine/Cardiology, Heart Center Leipzig at University of Leipzig, Germany (R.L.)
3. Department of Neurosciences, University of Padova, Italy (M.C.)
4. Department of Internal Medicine, King Abdulaziz University Hospital, College of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia (A.R.A.)
5. Department of Neurology, Stanford Medical Center, Palo Alto, CA (D.-I.S., M.M.)
6. University of Virginia School of Medicine, Charlottesville (J.W.).