作者单位:Brown Univ, Dept Med, Div Cardiol, Alpert Med Sch, 830 Chalkstone Ave, Providence, RI 02908 USA[1]Univ Sao Paulo, Univ Hosp, Div Internal Med, Sao Paulo, Brazil[2]Univ Florida, Coll Med, Dept Med, Malcolm Randall VA Med Ctr, Gainesville, FL USA[3]