title: Long-Term Outcomes of Abdominal Aortic Aneurysm in the Medicare Population.
abstract: BACKGROUND
  Randomized trials and observational studies have shown that perioperative morbidity and mortality are lower with endovascular repair of abdominal aortic aneurysm than with open repair, but the survival benefit is not sustained. In addition, concerns have been raised about the long-term risk of aneurysm rupture or the need for reintervention after endovascular repair.
  
  
  METHODS
  We assessed perioperative and long-term survival, reinterventions, and complications after endovascular repair as compared with open repair of abdominal aortic aneurysm in propensity-score-matched cohorts of Medicare beneficiaries who underwent repair during the period from 2001 through 2008 and were followed through 2009.
  
  
  RESULTS
  We identified 39,966 matched pairs of patients who had undergone either open repair or endovascular repair. The overall perioperative mortality was 1.6% with endovascular repair versus 5.2% with open repair (P<0.001). From 2001 through 2008, perioperative mortality decreased by 0.8 percentage points among patients who underwent endovascular repair (P=0.001) and by 0.6 percentage points among patients who underwent open repair (P=0.01). The rate of conversion from endovascular to open repair decreased from 2.2% in 2001 to 0.3% in 2008 (P<0.001). The rate of survival was significantly higher after endovascular repair than after open repair through the first 3 years of follow-up, after which time the rates of survival were similar. Through 8 years of follow-up, interventions related to the management of the aneurysm or its complications were more common after endovascular repair, whereas interventions for complications related to laparotomy were more common after open repair. Aneurysm rupture occurred in 5.4% of patients after endovascular repair versus 1.4% of patients after open repair through 8 years of follow-up (P<0.001). The rate of total reinterventions at 2 years after endovascular repair decreased over time (from 10.4% among patients who underwent procedures in 2001 to 9.1% among patients who underwent procedures in 2007).
  
  
  CONCLUSIONS
  Endovascular repair, as compared with open repair, of abdominal aortic aneurysm was associated with a substantial early survival advantage that gradually decreased over time. The rate of late rupture was significantly higher after endovascular repair than after open repair. The outcomes of endovascular repair have been improving over time. (Funded by the National Institutes of Health.).
authors.affiliation: From the Departments of Surgery (M.L.S., D.B.B., T.C., J.C.M, J.D.) and Medicine (B.E.L.), Beth Israel Deaconess Medical Center, and the Department of Health Care Policy, Harvard Medical School (B.E.L.) - both in Boston; and the Institute for Health Policy and Clinical Practice, Geisel School of Medicine at Dartmouth, Lebanon, NH (A.J.O.).
authors.forename: Marc L
authors.initials: ML
authors.lastname: Schermerhorn
authors.forename: Dominique B
authors.initials: DB
authors.lastname: Buck
authors.forename: A James
authors.initials: AJ
authors.lastname: O'Malley
authors.forename: Thomas
authors.initials: T
authors.lastname: Curran
authors.forename: John C
authors.initials: JC
authors.lastname: McCallum
authors.forename: Jeremy
authors.initials: J
authors.lastname: Darling
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Landon
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000401:mortality / Q000601:surgery*; D001019:Aortic Rupture / Q000453:epidemiology; D057510:Endovascular Procedures; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007813:Laparotomy; D008297:Male; D006278:Medicare; D011183:Postoperative Complications / Q000453:epidemiology* / Q000401:mortality; D057216:Propensity Score; D012086:Reoperation / Q000706:statistics & numerical data; D015996:Survival Rate; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology; D014656:Vascular Surgical Procedures / Q000379:methods*