title: The use of intra-aortic balloon counterpulsation in patients with cardiogenic shock complicating acute myocardial infarction: data from the National Registry of Myocardial Infarction 2.
abstract: BACKGROUND
  Cardiogenic shock complicating acute myocardial infarction (AMI) remains the leading cause of death in patients hospitalized with AMI. Although several studies have demonstrated the importance of establishing and maintaining a patent infarct-related artery, it remains unclear as to whether intra-aortic balloon counterpulsation (IABP) provides incremental benefit to reperfusion therapy. The purpose of this study was to determine whether IABP use is associated with lower in-hospital mortality rates in patients with AMI complicated by cardiogenic shock in a large AMI registry.
  
  
  METHODS
  We evaluated patients participating in the National Registry of Myocardial Infarction 2 who had cardiogenic shock at initial examination or in whom cardiogenic shock developed during hospitalization (n = 23,180).
  
  
  RESULTS
  The mean age of patients in the study was 72 years, 54% were men, and the majority were white. The overall mortality rate in all patients who had cardiogenic shock or in whom cardiogenic shock developed was 70%. IABP was used in 7268 (31%) patients. IABP use was associated with a significant reduction in mortality rates in patients who received thrombolytic therapy (67% vs 49%) but was not associated with any benefit in patients treated with primary angioplasty (45% vs 47%). In a multivariate model, the use of IABP in conjunction with thrombolytic therapy decreased the odds of death by 18% (odds ratio, 0.82; 95% confidence interval, 0.72 to 0.93).
  
  
  CONCLUSIONS
  Patients with AMI complicated by cardiogenic shock may have substantial benefit from IABP when used in combination with thrombolytic therapy.
authors.affiliation: University of California, San Francisco, USA. barron.hal@gene.com
authors.forename: H V
authors.initials: HV
authors.lastname: Barron
authors.forename: N R
authors.initials: NR
authors.lastname: Every
authors.forename: L S
authors.initials: LS
authors.lastname: Parsons
authors.forename: B
authors.initials: B
authors.lastname: Angeja
authors.forename: R J
authors.initials: RJ
authors.lastname: Goldberg
authors.forename: J M
authors.initials: JM
authors.lastname: Gore
authors.forename: T M
authors.initials: TM
authors.lastname: Chou
mesh_terms: D000368:Aged; D017130:Angioplasty; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007423:Intra-Aortic Balloon Pumping / Q000706:statistics & numerical data*; D008297:Male; D009203:Myocardial Infarction / Q000401:mortality / Q000601:surgery / Q000628:therapy; D012042:Registries; D012189:Retrospective Studies; D012770:Shock, Cardiogenic / Q000401:mortality* / Q000601:surgery / Q000628:therapy*; D015912:Thrombolytic Therapy; D014481:United States / Q000453:epidemiology