title: Computed tomography-based study exploring the feasibility of endovascular treatment of type A aortic dissection in the Chinese population.
abstract: OBJECTIVE
  To characterize type A aortic dissection (TAAD) in the Chinese population using high-resolution computed tomography (CT) and explore potential candidacy for endovascular repair of TAAD.
  
  
  METHODS
  The imaging studies and medical records of all 302 patients presenting with TAAD at two Chinese hospitals from 2010 to 2013 were reviewed. Of these, 221 patients were excluded because of missing/inadequate preoperative CT scans. The remaining 91 patients (64 men; mean age 51.1±7.5 years) had CT data adequate to assess anatomical suitability for endovascular treatment. Entry tears were identified using multiplanar reconstructions, while morphological measurements were based on a centerline of flow (CLF) technique. Suitability for endovascular treatment was based on a proximal landing zone ≥20 mm long, a true lumen aortic diameter ≤38 mm, and a total aortic diameter ≤46 mm; no coronary bypass grafts originating from the ascending aorta; no malfunctioning aortic valve; and good cerebral and cardiac perfusion.
  
  
  RESULTS
  In the 91 patients, the precise location of the primary proximal entry tear could be identified in only 34 (37.4%) patients; in these patients, the identifiable intimal tears were located 36.4±41.0 mm distal to the closest coronary artery. The CLF was successfully generated in the CT scans of all patients; the mean lumen and total aortic lumen diameters at the entry tear level were 37.6±6.3 and 44.3±13.3 mm, respectively. Based on the CT measurements, stent-graft repair would have been anatomically feasible in 35 (38.5%) patients. No proximal landing zone (n=23), large aortic diameter (n=15), abnormal aortic valve (n=10), previous coronary bypass graft surgery (n=5), and poor cerebral and cardiac perfusion (n=3) were obstacles that affected the suitability for this treatment.
  
  
  CONCLUSIONS
  Based on high-resolution CT scans, our pilot study suggested that 38% of Chinese patients with TAAD could potentially be treated by stent-grafting based on the anatomical characteristics of the proximal dissection.
authors.affiliation: Department of Vascular Surgery, Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Nanjing, People's Republic of China.
authors.forename: Chen
authors.initials: C
authors.lastname: Huang
authors.forename: Min
authors.initials: M
authors.lastname: Zhou
authors.forename: Zhao
authors.initials: Z
authors.lastname: Liu
authors.forename: Dian
authors.initials: D
authors.lastname: Huang
authors.forename: Feng
authors.initials: F
authors.lastname: Ran
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Ming
authors.initials: M
authors.lastname: Zhang
authors.forename: Cheng
authors.initials: C
authors.lastname: Liu
authors.forename: Chen
authors.initials: C
authors.lastname: Liu
authors.forename: Tong
authors.initials: T
authors.lastname: Qiao
authors.forename: Changjian
authors.initials: C
authors.lastname: Liu
mesh_terms: D000328:Adult; D000784:Aortic Dissection / Q000000981:diagnostic imaging* / Q000208:ethnology / Q000601:surgery*; D017545:Aortic Aneurysm, Thoracic / Q000000981:diagnostic imaging* / Q000208:ethnology / Q000601:surgery*; D001027:Aortography / Q000379:methods*; D044466:Asian People; D019917:Blood Vessel Prosthesis Implantation; D002681:China / Q000453:epidemiology; D057510:Endovascular Procedures; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D018579:Patient Selection; D010865:Pilot Projects; D011237:Predictive Value of Tests; D013997:Time Factors
keywords: Chinese population; anatomical suitability; aortic diameter; ascending aorta; computed tomographic angiography; endovascular repair; entry tear; intimal tear; proximal landing zone; race; stent-graft; type A aortic dissection