1. Cardiology and Angiology Unit, Department of Clinical and Experimental Internal Medicine, Medical Research Institute, University of Alexandria, Egypt
2. Department of Cardiology, Faculty of Medicine, University of Alexandria, Egypt
3. Department of Cardiology, Faculty of Medicine, University of Alexandria, Egypt; Michigan State University, East Lansing, MI, US
4. Department of Cardiology, Faculty of Medicine, Ain Shams University, Cairo, Egypt