[1] Univ Utah, Div Cardiol, Salt Lake City, UT USA
[2] Brigham & Womens Hosp, Div Cardiovasc, Boston, MA 02115 USA
[3] Ohio State Univ, Dept Med, Columbus, OH 43210 USA
[4] Univ Alabama, Dept Med, Birmingham, AL 35294 USA
[5] Univ Cincinnati, Dept Cardiol, Cincinnati, OH USA
[6] Medtronic Inc, Heart Failure Res, Minneapolis, MN USA