title: The influence of thrombus, calcification, angulation, and tortuosity of attachment sites on the time to the first graft-related complication after endovascular aneurysm repair.
abstract: OBJECTIVE
  Endovascular aneurysm repair (EVAR) is associated with high graft-related complication rates during follow-up. Anatomical fit between patient and endograft could be an important factor for successful treatment. Aim was to assess whether extent of thrombus, calcification, angulation, and tortuosity are associated with occurrence of complications after EVAR.
  
  
  METHODS
  Patients in either United Kingdom EVAR trial 1 or 2 were included if they had undergone EVAR within 6 months of randomization and had a preoperative computed tomography (CT) scan of adequate quality in the core laboratory. Three-dimensional CT imaging was used to assess extent of preoperative thrombus, calcification, angulation, and tortuosity in aneurysm neck and iliac segments. Cox regression modeling, adjusted for the variables tested and for known confounding variables, was used to investigate whether these factors were associated with increased rates of reported first complications.
  
  
  RESULTS
  A total of 217 patients with 53 first graft-related complications were analyzed after a mean follow-up of 3.6 years. Adjusted hazard ratios (95% confidence intervals, P values) for complications per unit increase of variable were 0.96 (0.92-0.99, 0.018) for neck thrombus, 1.06 (1.00-1.12, 0.044) for neck calcification, 1.02 (1.00-1.05, 0.079) for neck angulation, 1.04 (1.01-1.06, 0.011) for common iliac thrombus, 0.96 (0.93-1.00, 0.033) for common iliac calcification, and 5.96 (1.53-23.28, 0.010) for common iliac tortuosity.
  
  
  CONCLUSIONS
  Increased neck angulation and calcification and common iliac thrombus and tortuosity are associated with higher rates of graft-related complications after EVAR. Increased neck thrombus and common iliac calcification appear to protect against complications. Careful evaluation of these factors prior to EVAR might lead to lower complication rates.
authors: Vascular Surgery Research Group, Imperial College London, Charing Cross Hospital, London, United Kingdom.
authors: Thomas R
authors: TR
authors: Wyss
authors: Florian
authors: F
authors: Dick
authors: Louise C
authors: LC
authors: Brown
authors: Roger M
authors: RM
authors: Greenhalgh
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D001027:Aortography / Q000379:methods; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects* / Q000295:instrumentation; D002114:Calcinosis / Q000150:complications* / Q000000981:diagnostic imaging; D057510:Endovascular Procedures / Q000009:adverse effects* / Q000295:instrumentation; D005260:Female; D006801:Humans; D007083:Iliac Artery / Q000000981:diagnostic imaging; D021621:Imaging, Three-Dimensional; D008297:Male; D016016:Proportional Hazards Models; D011474:Prosthesis Design; D011857:Radiographic Image Interpretation, Computer-Assisted; D018570:Risk Assessment; D012307:Risk Factors; D013927:Thrombosis / Q000150:complications* / Q000000981:diagnostic imaging; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D006113:United Kingdom