1. Saint Luke’s Mid America Heart Institute, Kansas City, Missouri, USA
2. University of Missouri–Kansas City, Kansas City, Missouri, USA
3. Intermountain Heart Institute, Murray, Utah, USA
4. McLaren Northern Michigan Hospital, Petoskey, Michigan, USA
5. Cardiac and Vascular Institute, Gainesville, Florida, USA
6. Swedish Medical Center, Seattle, Washington, USA
7. Cardiovascular Center–Frankfurt, Frankfurt, Germany
8. WellSpan York Hospital, York, Pennsylvania, USA
9. Division of Cardiology, University of Washington, Seattle, Washington, USA