title: Biomechanical Imaging Markers as Predictors of Abdominal Aortic Aneurysm Growth or Rupture: A Systematic Review.
abstract: Biomechanical characteristics, such as wall stress, are important in the pathogenesis of abdominal aortic aneurysms (AAA) and can be visualised and quantified using imaging techniques. This systematic review aims to present an overview of all biomechanical imaging markers that have been studied in relation to AAA growth and rupture.
  
  
  
  This systematic review followed the PRISMA guidelines. A search in Medline, Embase, and the Cochrane Library identified 1503 potentially relevant articles. Studies were included if they assessed biomechanical imaging markers and their potential association with growth or rupture.
  
  
  
  Twenty-seven articles comprising 1730 patients met the inclusion criteria. Eighteen studies performed wall stress analysis using finite element analysis (FEA), 13 of which used peak wall stress (PWS) to quantify wall stress. Ten of 13 case control FEA studies reported a significantly higher PWS for symptomatic or ruptured AAAs than for intact AAAs. However, in some studies there was confounding bias because of baseline differences in aneurysm diameter between groups. Clinical heterogeneity in methodology obstructed a meaningful meta-analysis of PWS. Three of five FEA studies reported a significant positive association between several wall stress markers, such as PWS and 99th percentile stress, and growth. One study reported a significant negative association and one other study reported no significant association. Studies assessing wall compliance, the augmentation index and wall stress analysis using Laplace's law, computational fluid dynamics and fluid structure interaction were also included in this systematic review.
  
  
  
  Although PWS is significantly higher in symptomatic or ruptured AAAs in most FEA studies, confounding bias, clinical heterogeneity, and lack of standardisation limit the interpretation and generalisability of the results. Also, there is conflicting evidence on whether increased wall stress is associated with growth.
authors: Department of Surgery, Academic Medical Center, Amsterdam, The Netherlands.
authors: R
authors: R
authors: Indrakusuma
authors: Department of Surgery, Academic Medical Center, Amsterdam, The Netherlands.
authors: H
authors: H
authors: Jalalzadeh
authors: Department of Radiology, Academic Medical Center, Amsterdam, The Netherlands.
authors: R N
authors: RN
authors: Planken
authors: Department of Radiology, Academic Medical Center, Amsterdam, The Netherlands; Department of Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, The Netherlands.
authors: H A
authors: HA
authors: Marquering
authors: Department of Surgery, Academic Medical Center, Amsterdam, The Netherlands.
authors: D A
authors: DA
authors: Legemate
authors: Department of Surgery, Academic Medical Center, Amsterdam, The Netherlands.
authors: M J W
authors: MJ
authors: Koelemay
authors: Department of Surgery, Academic Medical Center, Amsterdam, The Netherlands. Electronic address: r.balm@amc.uva.nl.
authors: R
authors: R
authors: Balm
mesh_terms: D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D001019:Aortic Rupture / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D001696:Biomechanical Phenomena / Q000502:physiology*; D018450:Disease Progression; D020342:Finite Element Analysis; D006801:Humans; D018570:Risk Assessment
keywords: Abdominal aortic aneurysm; Biomechanical phenomena; Diagnostic imaging; Growth; Ruptured aneurysm