title: Air bubbles are released by thoracic endograft deployment: An in vitro experimental study.
abstract: OBJECTIVE
  Embolic stroke is a dreaded complication of thoracic endovascular aortic repair. The prevailing theory about its cause is that particulate debris from atherosclerotic lesions in the aortic wall are dislodged by endovascular instruments and embolize to the brain. An alternative source of embolism might be air trapped in the endograft delivery system. The aim of this experimental study was to determine whether air is released during deployment of a thoracic endograft.
  
  
  METHODS
  In an experimental benchtop study, eight thoracic endografts (five Medtronic Valiant Thoracic and three Gore TAG) were deployed in a water-filled transparent container drained from air. Endografts were prepared and deployed according to their instructions for use. Deployment was filmed and the volume of air released was collected and measured in a calibrated syringe.
  
  
  RESULTS
  Air was released from all the endografts examined. Air volumes ranged from 0.1 to 0.3 mL for Medtronic Valiant Thoracic and from <0.025 to 0.04 mL for Gore TAG. The largest bubbles had a diameter of approximately 3 mm and came from the proximal end of the Medtronic Valiant device.
  
  
  CONCLUSIONS
  Air bubbles are released from thoracic endografts during deployment. Air embolism may be an alternative cause of stroke during thoracic endovascular aortic repair.
authors.affiliation: Department of Surgery, Varberg Hospital, Varberg, Sweden.
authors.forename: Kamuran
authors.initials: K
authors.lastname: Inci
authors.affiliation: Department of Radiology, Sahlgrenska University Hospital, Gothenburg, Sweden.
authors.forename: Giasemi
authors.initials: G
authors.lastname: Koutouzi
authors.affiliation: Department of Applied Mechanics, Chalmers University of Technology, Gothenburg, Sweden.
authors.forename: Valery
authors.initials: V
authors.lastname: Chernoray
authors.affiliation: Department of Thoracic Surgery, Sahlgrenska University Hospital, Gothenburg, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Jeppsson
authors.affiliation: Department of Applied Mechanics, Chalmers University of Technology, Gothenburg, Sweden.
authors.forename: Håkan
authors.initials: H
authors.lastname: Nilsson
authors.affiliation: Department of Radiology, Sahlgrenska University Hospital, Gothenburg, Sweden.
authors.forename: Mårten
authors.initials: M
authors.lastname: Falkenberg
keywords: Air; embolism; experimental; stroke; thoracic endovascular aortic repair