[1] Columbia Univ, Coll Phys & Surg, Med Ctr, Dept Cardiol, New York, NY 10032 USA
[2] Mayo Clin & Mayo Fdn, Div Cardiovasc Dis & Internal Med, Rochester, MN 55905 USA
[3] Mid Carolina Cardiol, Charlotte, NC USA
[4] Beth Israel Deaconess Med Ctr, Boston, MA 02215 USA
[5] Cardiovasc Res Fdn, New York, NY 10022 USA
[6] Duke Univ, Med Ctr, Durham, NC USA
[7] William Beaumont Hosp, Royal Oak, MI 48073 USA