title: Heartbeat-related displacement of the thoracic aorta in patients with chronic aortic dissection type B: quantification by dynamic CTA.
abstract: OBJECTIVE
  The purpose of this study was to characterize the heartbeat-related displacement of the thoracic aorta in patients with chronic aortic dissection type B (CADB).
  
  
  METHODS
  Electrocardiogram-gated computed tomography angiography was performed during inspiratory breath-hold in 11 patients with CADB: Collimation 16 mm x 1 mm, pitch 0.2, slice thickness 1mm, reconstruction increment 0.8 mm. Multiplanar reformations were taken for 20 equidistant time instances through both ascending (AAo) and descending aorta (true lumen, DAoT; false lumen, DAoF) and the vertex of the aortic arch (VA). In-plane vessel displacement was determined by region of interest analysis.
  
  
  RESULTS
  Mean displacement was 5.2+/-1.7 mm (AAo), 1.6+/-1.0 mm (VA), 0.9+/-0.4 mm (DAoT), and 1.1+/-0.4mm (DAoF). This indicated a significant reduction of displacement from AAo to VA and DAoT (p<0.05). The direction of displacement was anterior for AAo and cranial for VA.
  
  
  CONCLUSIONS
  In CADB, the thoracic aorta undergoes a heartbeat-related displacement that exhibits an unbalanced distribution of magnitude and direction along the thoracic vessel course. Since consecutive traction forces on the aortic wall have to be assumed, these observations may have implications on pathogenesis of and treatment strategies for CADB.
authors.affiliation: University of Heidelberg, Department of Diagnostic and Interventional Radiology, 69120 Heidelberg, Germany. tim.weber@med.uni-heidelberg.de
authors.forename: Tim F
authors.initials: TF
authors.lastname: Weber
authors.forename: Maria-Katharina
authors.initials: MK
authors.lastname: Ganten
authors.forename: Dittmar
authors.initials: D
authors.lastname: Böckler
authors.forename: Philipp
authors.initials: P
authors.lastname: Geisbüsch
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Kauczor
authors.forename: Hendrik
authors.initials: H
authors.lastname: von Tengg-Kobligk
mesh_terms: D000784:Aortic Dissection / Q000000981:diagnostic imaging*; D000792:Angiography / Q000379:methods*; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging*; D001014:Aortic Aneurysm / Q000000981:diagnostic imaging*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D009038:Motion; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D011860:Radiography, Abdominal; D013902:Radiography, Thoracic / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods*