[1] YALE UNIV, SCH MED,YALE SCH ORG & MANAGEMENT,DEPT MED, DIV CARDIOL, NEW HAVEN, CT 06510 USA
[2] BRIGHAM & WOMENS HOSP, DEPT MED, DIV GEN MED, BOSTON, MA 02115 USA
[3] BRIGHAM & WOMENS HOSP, DIV CARDIOVASC, BOSTON, MA 02115 USA
[4] HARVARD UNIV, SCH MED, BOSTON, MA 02115 USA