title: Predictors and outcomes of endoleaks in the Veterans Affairs Open Versus Endovascular Repair (OVER) Trial of Abdominal Aortic Aneurysms.
abstract: OBJECTIVE
  The Veterans Affairs Open Versus Endovascular Repair (OVER) Trial of Abdominal Aortic Aneurysms study was a randomized controlled trial comparing open vs endovascular repair (EVAR) in standard-risk patients with infrarenal aortic aneurysms. The analysis reported here identifies characteristics, risk factors, and long-term outcome of endoleaks in patients treated with EVAR in the OVER cohort.
  
  
  METHODS
  The OVER trial enrolled 881 patients, of whom 439 received successful EVAR. Logistic regression analysis was used to identify predictors for endoleaks and secondary interventions. Kaplan-Meier survival analysis, longitudinal plots, and generalized linear mixed models methods were used to describe time to endoleak detection, resolution, or death.
  
  
  RESULTS
  During a mean follow-up of 6.2 ± 2.4 years, 135 patients (30.5%) developed 187 endoleaks. Four patients with EVAR went on to rupture; these four patients did not all have an endoleak. Mortality between patients who did and did not develop endoleaks was not significantly different. The 187 endoleaks included 12% type I, 76% type II, 3% type III, 3% type IV, and 6% indeterminate. Patient demographics and vascular risk factors were not associated with endoleak development. The presence of endoleaks resulted in an increase in aneurysm diameter over time (P < .0001). Fifty-three percent of endoleaks resolved spontaneously, and 31.9% received secondary interventions. The initial aneurysm size independently predicted a need for secondary interventions (P < .0003). Delayed type II endoleaks (detected >1 year after EVAR) were associated with aneurysm enlargement compared with the early counterpart. There was no difference in aneurysm size or length of survival between type II and other types of endoleak.
  
  
  CONCLUSIONS
  We present one of the most comprehensive and longest follow-up analyses of patients treated with aortic endografts. Endoleaks were common and negatively affected aneurysm diameter reduction. Delayed type II endoleaks were associated with late aneurysm diameter enlargement. Endoleaks and aneurysm diameter enlargement were not associated with excess mortality compared with those without these features.
authors.affiliation: Division of Vascular Surgery, Department of Surgery, University of Maryland School of Medicine and the Baltimore Veterans Affairs Medical Center, Baltimore, Md. Electronic address: blal@smail.umaryland.edu.
authors.forename: Brajesh K
authors.initials: BK
authors.lastname: Lal
authors.affiliation: Division of Vascular Surgery, Department of Surgery, Stanford University and Veterans Affairs Palo Alto Health Care System, Palo Alto, Calif.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
authors.affiliation: Yale University Cancer Center, New Haven, Conn; Veterans Affairs Cooperative Studies Program Coordinating Center, Veterans Affairs Medical Center, West Haven, Conn.
authors.forename: Ziyi
authors.initials: Z
authors.lastname: Li
authors.affiliation: Veterans Affairs Cooperative Studies Program Coordinating Center, Veterans Affairs Medical Center, West Haven, Conn.
authors.forename: Tassos
authors.initials: T
authors.lastname: Kyriakides
authors.affiliation: Division of Vascular Surgery, Department of Surgery, University of Wisconsin School of Medicine and Public Health, Madison, Wisc.
authors.forename: Jon
authors.initials: J
authors.lastname: Matsumura
authors.affiliation: Department of Medicine, Veterans Affairs Health Care System, Minneapolis, Minn.
authors.forename: Frank A
authors.initials: FA
authors.lastname: Lederle
authors.affiliation: Division of Vascular Surgery, Department of Surgery, University of California-Davis, Sacramento, Calif.
authors.forename: Julie
authors.initials: J
authors.lastname: Freischlag
mesh_terms: D000368:Aged; D017544:Aortic Aneurysm, Abdominal / Q000401:mortality / Q000601:surgery*; D019917:Blood Vessel Prosthesis Implantation / Q000401:mortality; D057867:Endoleak / Q000453:epidemiology* / Q000401:mortality / Q000628:therapy; D057510:Endovascular Procedures; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012307:Risk Factors; D016896:Treatment Outcome