[1] Advocate Illinois Mason Med Cntr, Internal Med, Chicago, IL USA
[2] Univ Massachusetts, Sch Med, Dept Cardiol, Worcester, MA USA
[3] Wayne State Univ, Detroit Med Cntr, Internal Med, Detroit, MI USA
[4] Harlem Hosp Cntr, Internal Med, New York, NY USA
[5] Univ Iowa Hosp & Clin, Div Cardiovasc Dis, Iowa City, IA 52242 USA
[6] Rush Med Coll, Cardiol, Chicago, IL 60612 USA