1. Department of Cardiovascular Diseases, Mayo Clinic College of Medicine and Science, Rochester, MN (M.S.T., P.J.M.B.).
2. Division of Cardiovascular Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia (J.L.).
3. Leon H. Charney Division of Cardiology, Department of Medicine, New York University School of Medicine, New York, NY (N.R.S.).
4. Department of Obstetrics and Gynecology, Division of Maternal Fetal Medicine, Mayo Clinic College of Medicine, Rochester, MN (C.H.R.).