January 26th, 2015

Measuring FFR During Cardiac Cath: Time to Go with the Flow?

Anecdotally, we’ve noticed that the use of fractional flow reserve (FFR) during cardiac catheterization seems to be increasing, in both community and academic centers. We pose these questions to our fellow members on CardioExchange:

  • Do you feel that FFR is being overused, underused, or neither?
  • Should some sort of objective assessment be mandatory in outpatient PCI?
  • Do results with FFR vary among providers?
  • Does the use of FFR improve care?

Share your reactions with the CardioExchange community.

4 Responses to “Measuring FFR During Cardiac Cath: Time to Go with the Flow?”

  1. Ajay J Kirtane, MD, SM says:

    Brief answers:

    1. FFR is still underused. Outside of the LMCA,it (not IVUS, not OCT) should be the invasive standard for INTERMEDIATE lesion assessment (provided the clinical scenario is not clear).

    2. Absolutely not. No test is infallible, and all tests ought to be interpreted within the context of the patient/clinical scenario using Bayesian constructs of pre/post-test probability. If a symptomatic patient has a 90% proximal LAD stenosis, there is no need to FFR that lesion. If the same patient instead has a 70% lesion with anterior ischemia on stress testing, there is no need to FFR that lesion.

    3. Yes. There is significant variability in the way in which FFR is performed. Issues of ic vs. iv vasodilators, how the wire is equalized, whether pullbacks are performed, etc can all affect the reliability of a test. Another reason why “FFR” is not infallible – not all “documented FFR” is actually true FFR!

    4. FFR can definitely improve care if used in the right context, and if it is done properly and rigorously. However, we have definitely seen cases where the “wrong” clinical decision gets made using incorrectly applied/done FFR. On the other hand, FFR can also be used to safely defer PCI on lesions that might otherwise be treated – a deferral of therapy that is ultimately good for the patient.

  2. 1- Underused. We take the risk of bringing the patient to the cath lab to get answers to questions and then we don’t take the time to do the most thorough exam we can. If a patient has intermediate lesion, I think they should all be FFR’d. In the last decade, FFR is one of the few (if only) diagnostic/interventions we do for elective CAD that actually shows benefit (FAME2) over medical therapy.

    2- Mandatory is a strong word, but I do think we need to pull the FFR wire out more in elective PCI without non-invasive testing. A very short 90% LCx lesion may very well be FFR negative. The vessel and lesion characteristics should be taken into account. If we want to rid ourselves of the “oculo-stenotic” reflex in intervention, then we have to investigate lesions more thoroughly.

    3- Just like a hemodynamic assessment and a sat run during a RHC can vary by operator, so too can FFR. Referring providers know which cath docs to send a RHC to and I think that FFR is the same way.

    4- Without a doubt. Being able to tell a patient that there is a degree of blockage but in lay terms, “but no significant decrease if blood flow.” This gives patients a peace of mind. Also, FAME/FAME2 gives me peace of mind that intervening on ischemic coronaries improves outcomes.

  3. Chong Guan Chan, MBBS says:

    Does the small difference in the degree of stenosis make any difference in long term outcome?
    I have the impression that in this specific situation, quality of plaque determines the outcome.
    Is it wrong to treat a true angina medically?

  4. Saurav Chatterjee, MD says:

    A big criticism of FFR remains that it never influenced ‘hard’ clinical end-points like mortality and MI-and was shown to be significantly influencing care by improving rates of revascularization.Is there a way to further risk stratify +ve FFRs so that in certain population sub-groups they provide specific advantage with actual mortality and/ or MI? Also many contend that the true value of FFR is when its neg in that it provides reassurance that a coronary stenosis was unlikely to progress to an extent to cause MI or CV death-under what common situations can it be false negative?