1. Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway;
2. Department of Cardiothoracic Surgery, St. Olav's Hospital, Trondheim University Hospital, Trondheim, Norway;
3. Department of Cardiothoracic Anesthesiology and Intensive Care, St. Olav's Hospital, Trondheim University Hospital, Trondheim, Norway