[1] Cleveland Clin Fdn, Dept Cardiovasc Med, Cleveland, OH 44195 USA
[2] Hop Cardiol, F-59037 Lille, France
[3] Mayo Clin, Rochester, MN USA
[4] Montreal Heart Inst, Montreal, PQ H1T 1C8, Canada
[5] Lenox Hill Heart & Vasc Inst, New York, NY USA
[6] Washington Univ, St Louis, MO USA