1. MedStar Washington Hospital Center, Washington, DC, US
2. St Francis Hospital, Roslyn, New York, NY, US; Cardiovascular Research Foundation, New York, NY, US
3. St Francis Hospital, Roslyn, New York, NY, US
4. St Francis Hospital, Roslyn, New York, NY, US; Cardiovascular Research Foundation, New York, NY, US; Columbia University Medical Center, New York, NY, US