1. Division of Cardiology, Duke University Medical Center, Durham, NC 27710, USA
2. Division of Cardiology, Emory University, Atlanta, GA 30322, USA
3. Division of Cardiology, University Hospital V. I. Lenin, Holguin, Cuba
4. Atlanta Vascular Research Foundation, Atlanta, GA 30084, USA
5. Division of Cardiology, Emory University, Atlanta, GA, USA