METHODS AND RESULTS: We undertook an observational cohort study of 21,210
ST-segment elevation myocardial infarction patients treated between 2005-2015 at the eight
Heart Attack Centres in London, UK. Patients' details were recorded at the time of the procedure into local databases using the British Cardiac Intervention Society
percutaneous coronary intervention dataset. There were 1890 patients who presented with
cardiogenic shock. The primary outcome was all-cause mortality at a median follow-up of 4.1 years (interquartile range: 2.2-5.8 years). Increasing rates of
cardiogenic shock were seen over the course of the study with consistently high mortality rates of 45-70%. A total of 685 patients underwent intra-aortic balloon pump insertion during primary
percutaneous coronary intervention for
cardiogenic shock with decreasing rates over time. Those patients undergoing intra-aortic balloon pump
therapy were younger, more likely to have poor left ventricular function and less likely to have had previous
percutaneous coronary intervention compared to the control group. Procedural success rates were similar (86.0% vs 87.1%, p=0.292) although crude, in-hospital major
adverse cardiac event rates were higher (43.8% vs 33.7%, p<0.0001) in patients undergoing intra-aortic balloon pump
therapy. Kaplan-Meier analysis demonstrated significantly higher mortality rates in patients receiving intra-aortic balloon pump
therapy (50.9% intra-aortic balloon pump vs 39.9% control, p<0.0001) during the follow-up period. After multivariate Cox analysis (hazard ratio 1.04, 95% confidence interval 0.62-1.89) and the use of propensity matching (hazard ratio: 1.29, 95% confidence interval: 0.68-1.45) intra-aortic balloon pump
therapy was not associated with mortality.
CONCLUSION: