[1] John Radcliffe Hosp, Dept Cardiol, Oxford OX3 9DU, England
[2] Inst Hosp Jacques Cartier, Massy, France
[3] Erasmus Univ, Ctr Thorax, Med Ctr, NL-3000 DR Rotterdam, Netherlands
[4] Univ Leipzig, Herzzentrum, Leipzig, Germany
[5] CNR Massa, Inst Clin Physiol, Massa, Italy
[6] Maine Med Ctr, Portland, ME 04102 USA
[7] Boston Sci Corp, Natick, MA USA