[1] Oregon Hlth & Sci Univ, Portland, OR 97201 USA
[2] Univ Calif Los Angeles, Los Angeles, CA USA
[3] Univ Montreal, Montreal Heart Inst, Montreal, PQ H3C 3J7, Canada
[4] Univ Colorado, Denver, CO 80202 USA
[5] Childrens Hosp, Dept Cardiol, Boston, MA 02115 USA
[6] Brigham & Womens Hosp, Div Cardiol, Boston, MA 02115 USA
[7] Med Coll Wisconsin, Milwaukee, WI 53226 USA
[8] Montefiore Med Ctr, Albert Einstein Coll Med, Bronx, NY 10467 USA
[9] Columbia Univ, New York, NY USA
[10] Ohio State Univ, Columbus, OH 43210 USA
[11] Penn State Univ, Milton S Hershey Med Ctr, Hershey, PA 17033 USA
[12] Cincinnati Childrens Hosp, Cincinnati, OH USA