1. Department of Anatomy and Cell Biology, Faculty of Medicine, University of Extremadura, 06006 Badajoz, Spain
2. Department of Cardiology, Hospital Infanta Cristina, 06080 Badajoz, Spain
3. Department of Cardiology, Hospital Quirón, European University of Madrid, 28223 Madrid, Spain
4. Department of Radiology, University of Southern California, Los Angeles, CA 90089, USA