August 30th, 2011

Intra-Aortic Balloon Counterpulsation (IABP) Burned to a CRISP


Intra-aortic balloon counterpulsation (IABP) is a bust in AMI patients without cardiogenic shock, according to the Counterpulsation to Reduce Infarct Size Pre-PCI Acute Myocardial Infarction (CRISP AMI) trial.

This open-label, 30-center, randomized, controlled trial was performed to determine if a routine strategy of IABP before primary PCI (and continued for at least 12 hours afterward) would reduce infarct size in patients with acute anterior STEMI without cardiogenic shock. A 6-month follow-up for clinical events was also conducted.

The routine use of IABP in patients with anterior STEMI without cardiogenic shock did not lead to a reduction in infarct size or to an improvement in clinical outcomes at 6 months.







P value

4 days
     – Infarct size




30 days
    – Major bleeding or transfusion




    – Major vascular complications




6 months
   – Death




   – Composite (death, recurrent MI,
heart failure)





As the accompanying editorial points out, five randomized trials have previously assessed the role of IABP in patients with AMI without cardiogenic shock; in aggregate, they also show no mortality benefit (21 deaths in 518 patients in the IABP groups vs. 21 deaths in 536 patients in the control groups).

Based on this (and previous) studies, what is the role of IABP in AMI?  In the absence of cardiogenic shock, there’s no benefit.

What about IABP for AMI and cardiogenic shock?  Even though it’s “guideline-recommended,” it’s not been properly studied.  A randomized trial is underway, with plans to enroll 600 patients with STEMI and shock

Would you enroll your patients with cardiogenic shock in this trial, knowing there’s a chance they won’t get IABP?  

4 Responses to “Intra-Aortic Balloon Counterpulsation (IABP) Burned to a CRISP”

  1. A 3.3% absolute risk difference in mortality and 4.6% absolute risk difference in death, MI or heart failure would have been hailed as a triumph, if only the trial had been (or could be) powered for clinical outcomes!

    As for infarct size, I don’t know what to make of it’s clinical relevance or the current tools to detect it.
    I don’t think we would be hailing IABP if it had improved infarct size but not clinical outcomes!!

  2. William DeMedio, MD says:

    I don’t see the logic of using IABC outside of cardiogenic shock. It would seem to me the risk would outweigh the benefit. This study backs up what common sense should tell us.

    Competing interests pertaining specifically to this post, comment, or both:

  3. Even for patients with cardiogenic shock, is there sufficient data showing that any benefit of IABP outweighs its risks?

  4. Alain Efstratiou, MD says:

    Abdel-Wahab et al in Am J Car 2010 105:967-971 published their experience claiming that inserting IABP before PCI for STEMI is essential. I have found this to be true. Designing a multi-center study to prove this will depend largely on the quality of the operators as for example the studies on renal stenting have shown. The idea that IABP can help after PCI without shock, I think originated after an old study by Magnus Ohman done of course before the era of modern stents. I would still insert a balloon at the end of a case if I am not completely happy with the result.

    Competing interests pertaining specifically to this post, comment, or both: