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Updated: Apr 15, 2026
The Intra-Aortic Balloon Pump
Published on: February 5, 2021
Intra-aortic Balloon Pump Therapy for Acute Myocardial Infarction: A Meta-analysis
Yousif Ahmad1, Sayan Sen1, Matthew J Shun-Shin1
1International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, London, United Kingdom.
Importance:
Intra-aortic balloon pump (IABP) therapy is a widely used intervention for acute myocardial infarction with cardiogenic shock. Guidelines, which previously strongly recommended it, have recently undergone substantial change.
Objective:
To assess IABP efficacy in acute myocardial infarction.
Data Sources:
Human studies found in Pubmed, Embase, and Cochrane libraries through December 2014 and in reference lists of selected articles. Search strings were "myocardial infarction" or "acute coronary syndrome" and "intra-aortic balloon pump" or "counterpulsation."
Study Selection:
Randomized clinical trials (RCTs) and observational studies comparing use of IABP with no IABP in patients with acute myocardial infarction.
Data Extraction And Synthesis:
Two reviewers independently extracted the data, and risk of bias in RCTs was assessed using the Cochrane risk of bias tool. We conducted separate meta-analyses of the RCTs and observational studies. Data were quantitatively synthesized using random-effects meta-analysis.
Main Outcomes And Measures:
Thirty-day mortality.
Results:
There were 12 eligible RCTs randomizing 2123 patients. In the RCTs, IABP use had no statistically significant effect on mortality (odds ratio [OR], 0.96 [95% CI, 0.74-1.24]), with no significant heterogeneity among trials (I2 = 0%; P = .52). This result was consistent when studies were stratified by the presence (OR, 0.94 [95% CI, 0.69-1.28]; P = .69, I2 = 0%) or absence (OR, 0.98 [95% CI, 0.57-1.69]; P = .95, I2 = 17%) of cardiogenic shock. There were 15 eligible observational studies totaling 15 530 patients. Their results were mutually conflicting (heterogeneity I2 = 97%; P < .001), causing wide uncertainty in the summary estimate for the association with mortality (OR, 0.96 [95% CI, 0.54-1.70]). A simple index of baseline risk marker imbalance in the observational studies appeared to explain much of the heterogeneity in the observational data (R2meta = 46.2%; P < .001).
Conclusions And Relevance:
Use of IABP was not found to improve mortality among patients with acute myocardial infarction in the RCTs, regardless of whether patients had cardiogenic shock. The observational studies showed a variety of mutually contradictory associations between IABP therapy and mortality, much of which was explained by the differences between studies in the balance of risk factors between IABP and non-IABP groups.
