Coronary Arteries CT Fractional Flow Reserve FFR

  • FFRCT is a
    • noninvasive
    • image postprocessing technique that enables the
      • determination of physiologic significance of coronary artery stenosis by
      • using data acquired from standard, routine diagnostic coronary CT angiography studies.
      • by evaluating  blood pressure
      • of a partially blocked artery
    • Principles
      • flow is proportional to pressure,
        • if resistance is minimal and constant,
        • pressure can be used as a surrogate of flow during maximal hyperemia.
      • Thus, FFR is simply calculated by
        • using the distal coronary pressure of the stenosis
        • divided by the aortic pressure during maximal hyperemia.
    • dichotomous interpretation strategy to be considered in lesions with FFRCT
      • greater than 0.80 (normal) or
      • less than or equal to 0.75 (are associated with high likelihood of hemodynamic significance)