title: Cannulation of the noncalcified aorta generates particles of microembolic nature: an experimental study using pig aorta.
abstract: OBJECTIVE
  Aortic cannulation during cardiac surgery is a potential etiological factor for perioperative stroke. Cannulae may dislodge aortic-wall calcifications. In addition, the sharp edge of the cannula-tip may shear off vessel-wall tissue, which can be expelled into the lumen. This hypothesis concerning source of emboli was tested in a noncalcified aortic perfusion model.
  
  
  METHODS
  Pig aortas were pressurized and cannulated. Washout samples were collected before and after cannulation (n = 40). Particles were deposited onto a 10-microm filter and evaluated by microscopy and digital image analysis.
  
  
  RESULTS
  A higher incidence of particles generated by cannulation was noted as compared to before the maneuver (p < 0.001). This increase included small (<0.1 mm, p < 0.001) and intermediate-size particles (0.1-0.5 mm, p < 0.001). Particles above 0.5 mm were few and were not associated with cannulation.
  
  
  CONCLUSIONS
  Cannulation was a source of embolic material in the noncalcified aortic model. However, these particles were less than 0.5 mm in diameter and may contribute to neurocognitive decline after cardiac surgery.
authors.affiliation: Department of Surgical and Perioperative Science, Heart Center, Cardiothoracic Division, Umeå University Hospital, Umeå, Sweden. magnus.hedberg@vll.se
authors.forename: Magnus
authors.initials: M
authors.lastname: Hedberg
authors.forename: Bertil
authors.initials: B
authors.lastname: Funck
authors.forename: Karl Gunnar
authors.initials: KG
authors.lastname: Engström
mesh_terms: D000818:Animals; D001011:Aorta; D002404:Catheterization / Q000009:adverse effects*; D004195:Disease Models, Animal; D004617:Embolism / Q000209:etiology*; D020521:Stroke / Q000517:prevention & control*; D013552:Swine