[1] Univ Pittsburgh, Med Ctr, Dept Med, Heart & Vasc Inst, 200 Lothrop St,Scaife Hall,S-553, Pittsburgh, PA 15213 USA
[2] Washington Univ, Sch Med, Dept Med, 660 S Euclid Ave, St Louis, MO 63110 USA
[3] Henry Ford Hlth Syst, Dept Med, 205 N East Ave, Jackson, MI 49201 USA
[4] Univ Florida, Dept Med, Div Cardiovasc Med, 1600 SW Archer Rd M509, Gainesville, FL 32610 USA