1. Department of Internal Medicine, Baylor University Medical Center, Dallas, Texas
2. Baylor Heart and Vascular Institute, Dallas, Texas
3. Texas A&M University Health Science Center College of Medicine, Dallas, Texas
4. Baylor Jack and Jane Hamilton Heart and Vascular Hospital, Dallas, Texas
5. The Heart Hospital Baylor Plano, Plano, Texas
6. Baylor Scott & White Research Institute, Dallas, Texas