title: Impact of introducing endovascular aneurysm repair on treatment strategy for repair of abdominal aortic aneurysm--National Hospital Organization network study in Japan.
abstract: BACKGROUND
  The objective of the present study was to assess the hypothesis that the introduction of endovascular aneurysm repair (EVAR) into Japan has expanded the indication of abdominal aortic aneurysm (AAA) repair without increasing surgical mortality.
  
  
  RESULTS
  From 10 national hospitals, we registered a total of 2,154 consecutive patients (Open surgery [OS]: n=1,577, EVAR: n=577) over 8 years, divided into 4 time periods: Group I (2005-2006: n=522), Group II (2007-2008: n=475), Group III (2009-2010: n=551), Group IV, (2011-2012: n=606). Mean age increased over the 4 time periods (P<0.0001). The incidences of COPD, smoking history, history of abdominal surgery and concomitant malignancy significantly increased as well, while the numbers of patients with preoperative shock or high ASA status reduced over time. The proportion of EVAR in AAA repair increased from: 0% in Group I, 11.6% in Group II, 41.0% in Group III, to 48.8% in Group IV (P<0.0001). Early mortality was 0.8% in the EVAR and 3.4% in the OS (P<0.001) groups. Survival rates among the 4 groups free of all-cause death and aneurysm-related death at 1 year were 92.1-96.3% (P=0.1555) and 95.5-96.8% (P=0.9891), respectively. Multiple logistic regression analysis for surgical death failed to demonstrate survival advantage of EVAR over OS.
  
  
  CONCLUSIONS
  Introduction of EVAR expanded the indication of AAA repair without increasing mortality, while high risk for anesthesia and emergency cases reduced over time. UMIN-CTR (UMIN000008345).
authors.affiliation: Affiliations of the National Hospital Organization Network Study Group for Abdominal Aortic Aneurysm in Japan are listed as in the Appendix.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Handa
authors.forename: Masafumi
authors.initials: M
authors.lastname: Yamashita
authors.forename: Toshiki
authors.initials: T
authors.lastname: Takahashi
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Onohara
authors.forename: Minoru
authors.initials: M
authors.lastname: Okamoto
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Shimoe
authors.forename: Masahiro
authors.initials: M
authors.lastname: Okada
authors.forename: Yoshimitsu
authors.initials: Y
authors.lastname: Ishibashi
authors.forename: Fuminori
authors.initials: F
authors.lastname: Kasashima
authors.forename: Jyunji
authors.initials: J
authors.lastname: Kishimoto
authors.forename: Akihiro
authors.initials: A
authors.lastname: Mizuno
authors.forename: Jyun-ichi
authors.initials: J
authors.lastname: Kei
authors.forename: Mikizou
authors.initials: M
authors.lastname: Nakai
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Suhara
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Endo
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nishina
authors.forename: Tadashi
authors.initials: T
authors.lastname: Furuyama
authors.forename: Masakazu
authors.initials: M
authors.lastname: Kawasaki
authors.forename: Yoichirou
authors.initials: Y
authors.lastname: Ueno
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000401:mortality* / Q000601:surgery*; D044466:Asian People; D018572:Disease-Free Survival; D057510:Endovascular Procedures; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D015996:Survival Rate; D013997:Time Factors