1. Department of Cardiac Surgery; Zhongshan Hospital; Fudan University; Shanghai 200032 P. R. China
2. Shanghai Institute of Cardiovascular Disease; Shanghai 200032 P. R. China
3. Beijing Advanced Innovation Center for Biomedical Engineering; Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education; School of Biological Science and Medical Engineering; Beihang University; Beijing 100083 P. R. China
4. Division of Engineering in Medicine; Brigham and Women's Hospital; Harvard Medical School; Cambridge MA 02139 USA
5. Department of Chemistry and Institute of Biomedical Science; Fudan University; Shanghai 200433 P. R. China