Background: In previous guidelines, intra-aortic balloon pump (IABP) use was strongly recommended in the treatment of cardiogenic shock in the context of acute myocardial infarction. The recent IABP-SHOCK II trial demonstrated no benefit in short- and medium-term mortality with the use of IABP. It was our objective to evaluate in a real life nationwide population of patients with acute myocardial infarction the impact of IABP in short- and medium-term mortality.
Methods: We included patients admitted with acute myocardial infarction in Killip class IV in the first 24 hours, all submitted to urgent coronary angiography. Our study objective was the occurrence of hospital and six-month all-cause mortality.
Results: From the 33,300 patients included in the registry, 4.2% presented with Killip class IV in the first 24 hours and 646 (43.6%) were submitted to urgent coronary angiography. IABP was implanted in 19.8% of these patients. The IABP group was younger, had higher admission heart rate, more multivessel disease and more left main disease. There were 260 hospital deaths (40.2%), similar between groups (46.1% vs. 38.8%, p=0.132). IABP use was associated with a deleterious effect in patients with previous MI and beneficial effect in patients with mechanical complications. IABP use had a neutral effect on mortality (hazard ratio 1.14, 95% confidence interval 0.84-1.56). This was further confirmed in a propensity score matching analysis.
Conclusions: In a real life population of patients with acute myocardial infarction, the use of IABP for the treatment of cardiogenic shock was associated with a neutral effect.
Keywords: Intra-aortic balloon pump; acute myocardial infarction; cardiogenic shock.