What is the evidence for IABP in STEMI with and without cardiogenic shock?

Intraaortic balloon pump (IABP) is the most widely used left ventricular support device in a variety of indications. This review focuses on the current literature and discusses the evidence of IABP in ST-elevation myocardial infarction (STEMI) with and without cardiogenic shock. In high-risk STEMI patients without cardiogenic shock several randomized clinical trials have been performed. The majority of the studies could not demonstrate an efficacy benefit for IABP as adjunctive therapy in comparison to standard treatment alone. Hence, recent meta-analyses could not reveal diverging mortality rates at a higher incidence of stroke and major bleedings with IABP use independent of the type of reperfusion therapy. IABP in STEMI patients with cardiogenic shock is recommended according to current American College of Cardiology/American Heart Association (AHA/ACC) and European Society of Cardiology (ESC) guidelines. In recent meta-analyses, IABP in cardiogenic shock complicated by STEMI has been shown to be associated with decreased mortality. However, these beneficial effects are limited to patients treated with thrombolysis, whereas in patients undergoing mechanical revascularization IABP therapy is associated with an increase in mortality. Nevertheless, these data only arise from prospective and retrospective cohort studies, as up to date only one very small randomized clinical trial has been completed. In summary, in high-risk STEMI patients without cardiogenic shock, current data do not support the use of IABP and should only be considered as a standby and bailout strategy if patients develop haemodynamic instability. Current data on IABP in patients with cardiogenic shock complicated by STEMI are scarce and highly limited due to the nonrandomized design of previous trials. However, according to current AHA/ACC and ESC guidelines its use is recommended. Although recent meta-analyses challenge current AHA/ACC/ESC guidelines, adequately powered randomized studies are needed to elucidate the role of IABP in patients with acute myocardial infarction complicated by cardiogenic shock.