Intra-aortic balloon pumps (IABP) are devices that provide hemodynamic support during cardiogenic shock; the balloon inflates during diastole (improving coronary artery perfusion) and deflates during systole (reducing afterload and improving systemic perfusion). Click here to see a 41 second video illustrating how it works.
Several guidelines recommend placement of an IABP for patients in cardiogenic shock secondary to acute myocardial infarction (AMI), if early revascularization (e.g., CABG) is planned (Class I recommendation). Data behind this recommendation, however, is limited.
The IABP-SHOCK II trial was a randomized, multi-center, open-label study that enrolled 600 patients (598 in the analysis) with cardiogenic shock secondary to AMI (STEMI or NSTEMI). Patients were randomized to the control group (receiving standard therapy; N=298) or the experimental group (receiving IABP; N=300).
No significant difference was found between groups with respect to 30-day mortality (primary end-point), secondary end-points (e.g., time to hemodynamic stabilization, renal function, lactate levels, etc.), or complications (e.g., major bleeding, peripheral ischemic complications, etc.).
Bottom line: Perhaps it is time to reassess the approach to cardiogenic shock secondary to AMI when early revascularization is planned. At this time consultation with local expertise is recommended.