1. Cedars‐Sinai Smidt Heart Institute Los Angeles California USA
2. Baylor University Medical Center Dallas Texas USA
3. Columbia University New York New York USA
4. University of Pennsylvania Philadelphia Pennsylvania USA
5. Saint Luke's Hospital Kansas City Missouri USA
6. University of Michigan Ann Arbor Michigan USA
7. Lutheran Hospital Indiana University Fort Wayne Fort Wayne Indiana USA
8. Pennsylvania State University State College Pennsylvania USA
9. University of Wisconsin Madison Wisconsin USA
10. Montefiore Medical Center New York New York USA
11. Stanford University Palo Alto California USA
12. University of Alabama at Birmingham Birmingham Alabama USA
13. University of Chicago Chicago Illinois USA
14. Cleveland Clinic Cleveland Ohio USA
15. University of Utah Salt Lake City Utah USA