[1] Univ Glasgow, British Heart Fdn, Cardiovasc Res Ctr, Glasgow, Lanark, Scotland
[2] Case Western Reserve Univ, Dept Med, Lerner Coll Med, Cleveland Clin, Cleveland, OH 44106 USA
[3] Cleveland Clin, Dept Cardiovasc Med, Heart Vasc & Thorac Inst, Cleveland, OH 44106 USA
[4] Cleveland Clin Akron Gen, Sect Cardiovasc Res, Heart Vasc & Thorac Dept, Akron, OH USA
[5] Cleveland Clin, Dept Quantitat Hlth Sci, Lerner Res Inst, Cleveland, OH 44106 USA
[6] Harvard Med Sch, Cardiovasc Div, Brigham & Womens Hosp, Boston, MA 02115 USA