1. Section of Interventional Cardiology MedStar Washington Hospital Center Washington District of Columbia USA
2. Cardiovascular Branch, Division of Intramural Research National Heart, Lung and Blood Institute National Institutes of Health Bethesda Maryland USA
3. Section of Interventional Cardiology MedStar Union Memorial Hospital Baltimore Maryland USA
4. Department of Cardiology MedStar Washington Hospital Center Washington District of Columbia USA
5. Department of Cardiac Surgery MedStar Washington Hospital Center Washington District of Columbia USA