title: The preoperative intraaortic balloon pump in coronary bypass surgery: a lack of evidence of effectiveness.
abstract: BACKGROUND
  There is limited evidence demonstrating the effectiveness of preoperative intraaortic balloon pump (IABP) use in isolated coronary artery bypass graft (CABG) surgery. A single-center randomized trial demonstrated its benefit. We undertook a multicenter observational study to verify this finding.
  
  
  METHODS
  In 29,950 consecutive patients undergoing isolated CABG between 1995 and 2000 at 10 centers, we compared patients with and without a preoperative IABP. We also compared the effect of preoperative IABP use within 7 high-risk clinical subgroups. To validate the previous randomized trial, patients with any 2 of the following were also analyzed: left main > 70%, ejection fraction < 40%, redo CABG, or preoperative intravenous nitroglycerin.
  
  
  RESULTS
  Preoperative IABPs were used in 1896 patients (6.3%). These patients had more comorbid conditions and a higher crude mortality than those who did not have preoperative IABPs (9.5% vs 2.3%, P < .0001). Preoperative IABP patients were caliper matched to non-preoperative IABP patients using a propensity score. Excess mortality associated with preoperative IABP persisted (9.2% vs 5.8%, P = .0004). In 7 high-risk subgroups, mortality was significantly higher with preoperative IABP. We used propensity caliper matching to compare preoperative IABP with non-preoperative IABP patients who met trial criteria (n = 4332). Preoperative IABP was associated with higher mortality (11.0% vs 6.5%, P = .0009). Removing emergency patients did not alter results.
  
  
  CONCLUSIONS
  Use of preoperative IABPs was consistently associated with higher mortality. Despite detailed statistical analysis, we were unable to show benefit from preoperative IABP use or confirm the results of a single-center trial that demonstrated its benefit. Assessment of preoperative IABP efficacy will require a randomized trial.
authors.affiliation: Department of Surgery, Maritime Heart Center, Halifax, Nova Scotia, Canada. rogerbaskett@hotmail.com
authors.forename: Roger J F
authors.initials: RJ
authors.lastname: Baskett
authors.forename: Gerald T
authors.initials: GT
authors.lastname: O'Connor
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Hirsch
authors.forename: William A
authors.initials: WA
authors.lastname: Ghali
authors.forename: Kathryn A
authors.initials: KA
authors.lastname: Sabadosa
authors.forename: Jeremy R
authors.initials: JR
authors.lastname: Morton
authors.forename: Cathy S
authors.initials: CS
authors.lastname: Ross
authors.forename: Felix
authors.initials: F
authors.lastname: Hernandez
authors.forename: William C
authors.initials: WC
authors.lastname: Nugent
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Lahey
authors.forename: Donato
authors.initials: D
authors.lastname: Sisto
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Dacey
authors.forename: John D
authors.initials: JD
authors.lastname: Klemperer
authors.forename: Robert E
authors.initials: RE
authors.lastname: Helm
authors.forename: Andrew
authors.initials: A
authors.lastname: Maitland
mesh_terms: D000368:Aged; D015331:Cohort Studies; D001026:Coronary Artery Bypass / Q000401:mortality; D005260:Female; D006801:Humans; D007423:Intra-Aortic Balloon Pumping; D008297:Male; D011300:Preoperative Care; D011446:Prospective Studies; D018570:Risk Assessment; D016896:Treatment Outcome