title: Successful ventricular transapical thoracic endovascular graft deployment in a pig model.
abstract: OBJECTIVE
  Aortoiliac occlusive disease may preclude retrograde thoracic endovascular aortic repair. This study evaluated the physiologic and anatomic feasibility of introducing an aortic endograft in an antegrade manner into the descending thoracic aorta of a pig through the left ventricular apex.
  
  
  METHODS
  Twelve adult pigs were to undergo antegrade endograft deployment. Under fluoroscopic guidance, a stiff guidewire was introduced past the aortic valve and into the distal abdominal aorta through the left ventricular apex on a beating heart. An 18F introducer sheath containing a 24 x 36-mm aortic endograft was introduced and deployed in the descending thoracic aorta. The accuracy of graft delivery was determined at necropsy by measuring the distance from the trailing edge of the graft to the downstream margin of the ostium of the left subclavian artery. Aortic valve competency was assessed angiographically and at necropsy. Left ventricular function was assessed angiographically. Five hemodynamic and respiratory variables were recorded at 12 stages during the procedure and assessed for significant changes from baseline.
  
  
  RESULTS
  One animal died during the sternotomy. All remaining pigs survived the experiment with minimal hemodynamic support. A significant drop in systolic blood pressure (75 +/- 2 to 60 +/- 4 mm Hg, P = .05) was noted when the aortic valve was crossed with an 18F sheath. The systolic blood pressure returned to baseline on endograft deployment and at the end of the procedure. Bradycardia was noted at several stages of the procedure, requiring treatment in two pigs. Eleven endografts were deployed; seven grafts were delivered within 5 mm and three grafts within 10 to 20 mm of the intended landing point. One graft was deployed 10 mm too proximally, covering the left subclavian artery. No aortic valvular insufficiency or left ventricular dysfunction was noted.
  
  
  CONCLUSIONS
  An aortic endograft can be delivered in an antegrade manner transapically into the descending thoracic aorta in a pig model with a reasonable degree of accuracy and minimal hemodynamic compromise.
authors.affiliation: Division of Vascular Surgery, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: S Marlene
authors.initials: SM
authors.lastname: Grenon
authors.forename: Shaun
authors.initials: S
authors.lastname: MacDonald
authors.forename: Ravindar S
authors.initials: RS
authors.lastname: Sidhu
authors.forename: John D
authors.initials: JD
authors.lastname: Reid
authors.forename: Anson
authors.initials: A
authors.lastname: Cheung
authors.forename: York
authors.initials: Y
authors.lastname: Hsiang
authors.forename: Jason
authors.initials: J
authors.lastname: Clement
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D005240:Feasibility Studies; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000601:surgery; D006439:Hemodynamics; D023421:Models, Animal; D011474:Prosthesis Design; D015641:Radiography, Interventional; D012119:Respiration; D013249:Sternum / Q000601:surgery; D013552:Swine