Authors
Georgi J. Stoitsev
Department of Surgery, Medical University – Pleven, Bulgaria
Department of Cardiac Surgery, St. Anna University Hospital, Sofia, Bulgaria
Veselin D. Gavrilov
Department of Anaesthesiology and Intensive Care, Blocks Hospital, Sofia, Bulgaria
Vassil A. Gegouskov
Department of Cardiac Surgery, St. Anna University Hospital, Sofia, Bulgaria
Research Institute, Medical University – Pleven, Bulgaria