[1] Johns Hopkins Univ, Baltimore, MD USA
[2] Johns Hopkins Univ, Div Cardiovasc Imaging, Baltimore, MD USA
[3] NHLBI, Rockledge Cntr 2, OD, NIH, Bethesda, MD 20892 USA
[4] Univ Calif Los Angeles, Sch Med, Los Angeles, CA USA
[5] Wake Forest Univ Hlth Sci, Winston Salem, NC USA
[6] NIH, Bethesda, MD 20892 USA