title: The Impact of Aortic Occlusion Balloon on Mortality After Endovascular Repair of Ruptured Abdominal Aortic Aneurysms: A Meta-analysis and Meta-regression Analysis.
abstract: BACKGROUND
  We aimed to investigate whether the use of aortic occlusion balloon (AOB) has an impact on mortality of patients undergoing endovascular repair of ruptured abdominal aortic aneurysms (RAAAs).
  
  
  METHODS
  A meta-analysis of the English-language literature was undertaken through February 2013. Articles reporting data on outcome after endovascular repair of RAAAs were identified and information regarding the use of AOB was sought.
  
  
  RESULTS
  Included in this meta-analysis were 39 eligible studies reporting 1277 patients. The pooled perioperative mortality was 21.6% (95% CI 18.1-25.1%). There was significant within-study heterogeneity (I(2) 50.2%, P < 0.001). A total of 200 patients required AOB with an estimated pooled proportion of 14.1% (8.9-19.3%). Individual random-effects meta-regression investigating the effect of AOB and other risk factors on mortality revealed a significant linear association of hemodynamic instability, bifurcated endograft approach, and primary conversion to open repair with mortality and a nonlinear (second degree polynomial) association of AOB with mortality. On multivariable meta-regression models, both hemodynamic instability and AOB were found to be statistically significant, independent predictors of mortality. In particular, there was a statistically significant negative correlation between AOB and mortality and a positive effect of hemodynamic instability on mortality. In practical terms, mortality was significantly higher in studies with a higher proportion of hemodynamically unstable patients and lower in studies with a higher rate of AOB use.
  
  
  CONCLUSIONS
  This study provides meta-analytical evidence that the use of an AOB in unstable RAAA patients undergoing endovascular repair may improve the results.
authors.affiliation: 5th Department of Surgery, Medical School, Aristotle University of Thessaloniki, Hippocratio Hospital, Konstantinoupoleos 49, 546 42, Thessaloniki, Greece. ckarkos@hotmail.com.
authors.forename: Christos D
authors.initials: CD
authors.lastname: Karkos
authors.affiliation: 5th Department of Surgery, Medical School, Aristotle University of Thessaloniki, Hippocratio Hospital, Konstantinoupoleos 49, 546 42, Thessaloniki, Greece.
authors.forename: Christina T
authors.initials: CT
authors.lastname: Papadimitriou
authors.affiliation: Institute for Environmental Studies, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
authors.forename: Theodoros N
authors.initials: TN
authors.lastname: Chatzivasileiadis
authors.affiliation: Health Economist/Statistical Programmer, Erasmus Universiteit Rotterdam, Rotterdam, The Netherlands.
authors.forename: Nikoletta S
authors.initials: NS
authors.lastname: Kapsali
authors.affiliation: 5th Department of Surgery, Medical School, Aristotle University of Thessaloniki, Hippocratio Hospital, Konstantinoupoleos 49, 546 42, Thessaloniki, Greece.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Kalogirou
authors.affiliation: 5th Department of Surgery, Medical School, Aristotle University of Thessaloniki, Hippocratio Hospital, Konstantinoupoleos 49, 546 42, Thessaloniki, Greece.
authors.forename: Ioakeim T
authors.initials: IT
authors.lastname: Giagtzidis
authors.affiliation: 5th Department of Surgery, Medical School, Aristotle University of Thessaloniki, Hippocratio Hospital, Konstantinoupoleos 49, 546 42, Thessaloniki, Greece.
authors.forename: Konstantinos O
authors.initials: KO
authors.lastname: Papazoglou
mesh_terms: D017544:Aortic Aneurysm, Abdominal / Q000628:therapy*; D001019:Aortic Rupture / Q000628:therapy*; D021721:Balloon Occlusion; D057510:Endovascular Procedures; D006801:Humans; D012307:Risk Factors; D016896:Treatment Outcome
keywords: Abdominal aortic aneurysms (AAA); Acute aortic syndrome; Aorta; Arterial intervention; Endovascular aneurysm; Repair/endovascular aortic repair (EVAR)