1. Ultrasound and Elasticity Imaging Laboratory, Department of Biomedical Engineering, Columbia University , 680 West 168th Street, Physicians & Surgeons 14-418, New York, NY, 10032 , USA
2. Division of Cardiology, Department of Medicine and Vagelos College of Physicians and Surgeons, Columbia University , 177 Fort Washington Avenue, Milstein 5-435F, New York, NY, 10032 , USA
3. Department of Radiology, Columbia University Medical Center , 630 West 168 Street, Physicians & Surgeons Box 28, New York, NY, 10032 , USA