[1] Tufts Univ, New England Med Ctr, Hypertroph Cardiomyopathy Ctr, Boston, MA 02111 USA
[2] Tufts Univ, New England Med Ctr, Div Cardiol, Cardiac Catheterizat Lab, Boston, MA 02111 USA
[3] Minneapolis Heart Inst Fdn, Hypertroph Cardiomyopathy Ctr, Minneapolis, MN USA