title: Quantification of motion of the thoracic aorta after ascending aortic repair of type-A dissection.
abstract: OBJECTIVE
  To quantify cardiac and respiratory deformations of the thoracic aorta after ascending aortic graft repair.
  
  
  METHODS
  Eight patients were scanned with cardiac-resolved computed tomography angiography during inspiratory/expiratory breath-holds. Aortic centerlines and lumen were extracted to compute the arclength, curvature, angulation, and cross-section shape.
  
  
  RESULTS
  From systole to diastole, the angle of graft [Formula: see text] arch increased by 2.4[Formula: see text] ± 1.8[Formula: see text] (P < 0.01) and the angle of arch [Formula: see text] descending aorta decreased by 2.4[Formula: see text] ± 2.6[Formula: see text] (P < 0.05), while the effective diameter of the proximal arch decreased by 2.4 ± 1.9% (P < 0.01), a greater change than those of the graft or distal arch (P < 0.05). From inspiration to expiration, the angle of graft [Formula: see text] arch increased by 2.8[Formula: see text] ± 2.6[Formula: see text] (P < 0.02) with the peak curvature increase (P < 0.05). Shorter graft length was correlated with greater cardiac-induced graft [Formula: see text] arch angulation, and longer graft length was correlated with greater respiratory-induced arch [Formula: see text] descending aorta angulation (R [Formula: see text] 0.50).
  
  
  CONCLUSIONS
  The thoracic aorta changed curvature and angulation with cardiac and respiratory influences, driven by aortic root and arch motion. The thoracic aortic geometry and deformation are correlated with the ascending aortic graft length.
authors.affiliation: Department of Surgery, Stanford University, 300 Pasteur Dr. Suite H3600, Stanford, CA, 94305-5642, USA. gysuh@stanford.edu.
authors.forename: Ga-Young
authors.initials: GY
authors.lastname: Suh
authors.affiliation: Department of Radiology, Stanford University, Stanford, CA, USA.
authors.forename: Dominik
authors.initials: D
authors.lastname: Fleischmann
authors.affiliation: Department of Cardiothoracic Surgery, Stanford University, Stanford, CA, USA.
authors.forename: Ramin E
authors.initials: RE
authors.lastname: Beygui
authors.affiliation: Department of Surgery, Stanford University, 300 Pasteur Dr. Suite H3600, Stanford, CA, 94305-5642, USA.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Cheng
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000784:Aortic Dissection / Q000601:surgery*; D001011:Aorta / Q000601:surgery*; D001013:Aorta, Thoracic / Q000601:surgery*; D002315:Cardiopulmonary Bypass; D000072226:Computed Tomography Angiography; D003971:Diastole; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D009038:Motion; D019651:Plastic Surgery Procedures / Q000379:methods*; D013599:Systole; D014057:Tomography, X-Ray Computed; D014656:Vascular Surgical Procedures / Q000379:methods*
keywords: Cardiac motion; Dissection; Modeling; Respiration; Thoracic aorta