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Automatically detected fractional flow reserve (FFR) is often lower than true steady-state FFR, potentially impacting treatment decisions. Careful interpretation of FFR values near the cutoff is crucial.

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Area of Science:

  • Cardiovascular Medicine
  • Interventional Cardiology
  • Diagnostic Imaging

Background:

  • Fractional flow reserve (FFR) is a standard diagnostic tool in cardiac catheterization.
  • FFR analysis traditionally relies on pressure recordings during steady-state hyperemia.
  • Automated FFR detection may not always capture true steady-state conditions.

Purpose of the Study:

  • To compare automatically detected FFR with true steady-state FFR.
  • To evaluate the clinical implications of discrepancies between automated and steady-state FFR measurements.

Main Methods:

  • Analysis of pressure tracings from 105 coronary lesions in 77 patients.
  • Intravenous adenosine used to achieve maximum hyperemia (140 µg/kg/min).
  • Comparison of automatically calculated FFR with manually determined steady-state FFR.

Main Results:

  • In 40% of lesions, automatically detected FFR was lower than steady-state FFR.
  • A mean bias of 0.009 was observed between the two methods.
  • Different treatment recommendations occurred in 3.8% of cases, with instantaneous wave-free ratio confirming steady-state FFR.

Conclusions:

  • Automated FFR detection can be lower than steady-state FFR in a significant proportion of cases.
  • Close attention is needed when interpreting automated FFR values near the diagnostic cutoff.
  • Discrepancies may influence clinical decision-making in interventional cardiology.