title: Operative Results and Clinical Features of Chronic Stanford Type B Aortic Dissection: Examination of 234 Patients Over 6 Years.
abstract: OBJECTIVE
  Recently, the indications for thoracic endovascular aortic repair (TEVAR) have been expanding, and the applicability of TEVAR for acute type B aortic dissection (TBAD) is proposed with regard to the high mortality of open surgery for chronic TBAD. TEVAR in the acute phase may lead to remodeling of the false lumen (FL), but it is controversial whether it completely resolves the aortic expansion in the chronic phase. In this study, operative results and the relationship between FL status and the time before surgical intervention were retrospectively analyzed.
  
  
  METHODS
  From January 2008 to September 2013, 234 patients underwent open surgery for chronic TBAD. Most patients were on left heart bypass. By considering Japanese aortic disease treatment guidelines and the smaller physique of Japanese patients, operative indications were aneurysm >50 mm in diameter or rapid aneurysm enlargement of >5 mm in a 6 month period.
  
  
  RESULTS
  In 180 cases, the FL was patent. The mean interval between onset of TBAD and operation was 61 ± 54 months. There was no significant difference between patients in the patent FL group and those in the thrombosed FL group (p = .44). Mean ratio of FL diameter to maximum aortic diameter (FL/AD) was 0.64 ± 0.21. There was no correlation between FL and AD before the operation (r = .12). Descending thoracic aortic replacement (DTAR) was performed in 127 cases and thoracic ascending aortic replacement (TAAR) in 107 cases (Crawford type I, n = 9; Crawford type II, n = 65; Crawford type III and IV, n = 22, respectively; Safi type V, n = 11). The overall operative mortality was 6.8%: 3.9% (5/127) for DTAR and 10.3% (11/107) for TAAR. The three year survival was 86.7, and the freedom from re-intervention rate was 97.0%.
  
  
  CONCLUSIONS
  Enlargement of uncomplicated TBAD in the chronic phase was poorly related to FL status and the results of open repair have improved. However, further prospective study is necessary.
authors.affiliation: Kawasaki Aortic Center, Kawasaki Saiwai Hospital, Kawasaki, Japan. Electronic address: fujikawa.takuya@gmail.com.
authors.forename: T
authors.initials: T
authors.lastname: Fujikawa
authors.affiliation: Kawasaki Aortic Center, Kawasaki Saiwai Hospital, Kawasaki, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Yamamoto
authors.affiliation: Kawasaki Aortic Center, Kawasaki Saiwai Hospital, Kawasaki, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Sekine
authors.affiliation: Kawasaki Aortic Center, Kawasaki Saiwai Hospital, Kawasaki, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Oshima
authors.affiliation: Kawasaki Aortic Center, Kawasaki Saiwai Hospital, Kawasaki, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Kasai
authors.affiliation: Kawasaki Aortic Center, Kawasaki Saiwai Hospital, Kawasaki, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Mochida
authors.affiliation: Kawasaki Aortic Center, Kawasaki Saiwai Hospital, Kawasaki, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Ozaki
authors.affiliation: Kawasaki Aortic Center, Kawasaki Saiwai Hospital, Kawasaki, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Sasaguri
mesh_terms: D000368:Aged; D000784:Aortic Dissection / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D017545:Aortic Aneurysm, Thoracic / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000401:mortality; D002908:Chronic Disease; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000401:mortality / Q000601:surgery; D012086:Reoperation; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D061665:Time-to-Treatment; D016896:Treatment Outcome; D014654:Vascular Patency
keywords: Chronic dissection; Descending aorta thoraco-abdominal aorta; Open surgery; Stanford type B