title: Thrombus formation in aortic endografts.
abstract: OBJECTIVE
  To examine the incidence of intraprosthetic thrombotic deposits in aortic endografts.
  
  
  METHODS
  Transfemoral implantation of tube or bifurcated stent-grafts was performed in 82 patients (75 men; average age 67.7 years, range 25-88) for treatment of aneurysms of the abdominal (n = 73) or thoracic (n = 9) aorta in a 3.5-year period. Patients underwent 3-phase helical computed tomographic (CT) examinations at 3-month intervals. The length and cross-sectional area of any thrombotic deposits were measured from axial and 3-dimensional CT images.
  
  
  RESULTS
  Over a 12.1-month mean follow-up, intraluminal deposits of thrombotic material were observed in 19 (23.2%) patients, all with infrarenal endografts that were predominately of a bifurcated design. The first signs of thrombus formation occurred on average 7 months postoperatively (range 1 week to 20 months). In 16 patients, nonocclusive deposits of thrombotic material were seen in the aortic segment of the endograft; a graft limb was involved in 5 patients. Three graft limbs occluded owing to kinking; no thrombus was seen on CT scans taken prior to occlusion. In 3 cases the thrombotic deposits disappeared completely from the prosthesis lumen during follow-up.
  
  
  CONCLUSIONS
  Based on this small experience, nearly 1 in 5 patients may experience some degree of intraluminal thrombus following endovascular treatment of aortic aneurysms. Whether the deposition of thrombus is influenced by the geometry of the aortic stent-graft or by flow conditions within the prosthetic lumen must be determined in future studies.
authors.affiliation: Department of Radiology, University of Ulm, Germany. wegener-ulm@t-online.de
authors.forename: M
authors.initials: M
authors.lastname: Wegener
authors.forename: J
authors.initials: J
authors.lastname: Görich
authors.forename: S
authors.initials: S
authors.lastname: Krämer
authors.forename: T
authors.initials: T
authors.lastname: Fleiter
authors.forename: R
authors.initials: R
authors.lastname: Tomczak
authors.forename: R
authors.initials: R
authors.lastname: Scharrer-Pamler
authors.forename: X
authors.initials: X
authors.lastname: Kapfer
authors.forename: H J
authors.initials: HJ
authors.lastname: Brambs
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019412:Anatomy, Cross-Sectional; D001014:Aortic Aneurysm / Q000150:complications / Q000601:surgery; D001807:Blood Vessel Prosthesis / Q000009:adverse effects*; D019917:Blood Vessel Prosthesis Implantation; D005121:Extremities / Q000033:anatomy & histology / Q000098:blood supply; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D013927:Thrombosis / Q000175:diagnosis / Q000209:etiology*; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014656:Vascular Surgical Procedures