title: Descending aortic aneurysmal changes following surgery for acute DeBakey type I aortic dissection.
abstract: OBJECTIVE
  The aim of the study was to determine the risk factors for descending aortic aneurysmal changes following surgery for acute DeBakey type I aortic dissection.
  
  
  METHODS
  A total of 129 patients who underwent surgery for acute type I aortic dissection between 2000 and 2010 were evaluated by contrast-enhanced computed tomography (CT) at least 6 months later (median follow-up 29.5 months, interquartile range 16.3-49.3 months). The study endpoint was the development of aortic aneurysms (diameter >55 mm). Risk factors for aortic aneurysms were determined by Cox regression analysis.
  
  
  RESULTS
  Aortic dilatation occurred in 23 of the 129 (17.8%) patients. Aortic aneurysms were observed at the proximal descending in 19 (14.7%) patients, the mid descending in 12 (9.3%) patients, the distal descending in seven (5.4%) patients and at the abdominal aorta in one (0.8%) patient. Multivariate analysis showed that the luminal diameter of the proximal descending aorta on initial CT was the only significant and independent factor predicting aneurysm formation (hazard ratio 1.12, 95% confidence interval [CI] 1.02-1.22, P = 0.014). Receiver operating curves assessing the ability of preoperative proximal descending aorta diameter to predict aortic aneurysms showed an area under the curve of 0.72 (95% CI 0.60-0.84, P = 0.001), with a greatest accuracy at 40.95 mm (sensitivity 65.2%, specificity 78.3%). The 5-year freedom from aortic aneurysm rates in patients with proximal descending diameters ≤ 40 and >40 mm were 84.4 ± 6.6 and 55.6 ± 11.1%, respectively (P = 0.001).
  
  
  CONCLUSIONS
  The proximal descending aorta was the major site of aneurysm formation following surgery for acute type I aortic dissection. The large proximal descending aortic diameter on initial CT predicted the late aneurysm, suggesting that adjunctive procedures combined with aortic replacement are needed to prevent the late aneurysm.
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul,  Korea.
authors.forename: Joon Bum
authors.initials: JB
authors.lastname: Kim
authors.forename: Chee-Hoon
authors.initials: CH
authors.lastname: Lee
authors.forename: Taek Yeon
authors.initials: TY
authors.lastname: Lee
authors.forename: Sung-Ho
authors.initials: SH
authors.lastname: Jung
authors.forename: Suk Jung
authors.initials: SJ
authors.lastname: Choo
authors.forename: Jae Won
authors.initials: JW
authors.lastname: Lee
authors.forename: Cheol Hyun
authors.initials: CH
authors.lastname: Chung
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000784:Aortic Dissection / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery*; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging* / Q000473:pathology; D001014:Aortic Aneurysm / Q000000981:diagnostic imaging / Q000209:etiology / Q000401:mortality / Q000601:surgery*; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000209:etiology; D017545:Aortic Aneurysm, Thoracic / Q000000981:diagnostic imaging / Q000209:etiology; D019917:Blood Vessel Prosthesis Implantation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000209:etiology; D016016:Proportional Hazards Models; D012372:ROC Curve; D012086:Reoperation; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome