Department of Surgery-Vascular Surgery Unit, School of Medicine, University of Ioannina, Ioannina, Greece. Department of Anesthesiology, School of Medicine, University of Ioannina, Ioannina, Greece. Department of Internal Medicine, School of Medicine, University of Ioannina, Ioannina, Greece. First Department of Internal Medicine, School of Medicine, University of Athens, Athens, Greece. Department of Surgery-Vascular Surgery Unit, School of Medicine, University of Ioannina, Ioannina, Greece mimats@cc.uoi.gr milmats@gmail.com.