How are you taking part in this consultation?

You will not be able to change how you comment later.

You must be signed in to answer questions

    The content on this page is not current guidance and is only for the purposes of the consultation process.

    QAngio XA 3D QFR and CAAS vFFR imaging software for assessing coronary stenosis during invasive coronary angiography

    Closed for comments This consultation ended on at   Request commenting lead permission

    1 Recommendations

    1.1 QAngio XA 3D quantitative flow ratio (QAngio QFR) and CAAS vessel fractional flow reserve (CAAS vFFR) are not recommended for routine use during invasive coronary angiography to assess coronary stenosis in stable angina. QAngio QFR shows promise but its clinical effectiveness is uncertain. The diagnostic accuracy and clinical effectiveness of CAAS vFFR are uncertain.

    1.2 Further research is recommended (see section 5) on:

    • people's experiences of QAngio QFR and CAAS vFFR compared with the reference standards of FFR or instantaneous wave-free ratio (iFR)

    • test failure rates of QAngio QFR and CAAS vFFR and how these affect whether revascularisation is done in clinical practice

    • the clinical benefit of using QAngio QFR and CAAS vFFR

    • the diagnostic accuracy of CAAS vFFR.

    Why the committee made these recommendations

    FFR or iFR can be used with invasive coronary angiography to assess coronary stenosis. However, FFR and iFR can have unpleasant side effects and increase the risk of adverse events, such as damage to the artery.

    CAAS vFFR and QAngio QFR use X-ray images taken during an invasive coronary angiography to construct a 3D image of the artery. This image is used to estimate the effect of coronary stenosis on blood flow through the artery without the side effects and risk of adverse events of FFR or iFR.

    Evidence shows that the diagnostic accuracy of QAngio QFR is similar to FFR, but the diagnostic accuracy of CAAS vFFR is very uncertain. Whether QAngio QFR or CAAS vFFR affect clinical outcomes and improve quality of life is also uncertain. Further research is recommended to address these uncertainties.

    The cost-effectiveness estimates for CAAS vFFR and QAngio QFR are uncertain but suggest that they are more cost effective than invasive coronary angiography alone. The estimates suggest they are less cost effective than FFR and iFR.

    Because there are multiple tests available that assess coronary stenosis it is not clear what clinical benefits QAngio QFR and CAAS vFFR offer. Therefore, the tests are not recommended for use in the NHS, and further research is recommended.