UMCG, Groningen, Netherlands
Eastern Virginia Medical School, Norfolk, Virginia, United States
Cairo, Cairo, Egypt
Faculty of Medicine,Beni-Suef University, Banī Suwayf, Egypt
National Heart Centre Singapore, Singapore, Singapore
Leiden Universitiy Medical Center (LUMC), Leiden, Noord Holland, Netherlands
Faculty of medicine Fayoum univesity, Fayoum, Egypt
Fayoum University, Fayoum, Egypt
Erasme hospital, Brussels, Belgium
Seoul National University Hospital, Seoul, Korea, Republic of