Quantitative flow ratio will supplant wire-based physiological indices: pros and cons

Quantitative flow ratio (QFR) represents a physiological index derived from angiography through three-dimensional (3D) quantitative coronary analysis. When compared to coronary angiography, QFR showed better performance both for guiding percutaneous coronary intervention (PCI) in case of intermediate coronary lesions and for optimising PCI results. In addition, QFR showed good diagnostic agreement with other established physiological indices, such as fractional flow reserve (FFR), with important practical advantages (e.g., fast and offline analysis). However, data on clinical outcomes in comparisons to wire-based physiological indices as well as validation studies in complex PCI and high-risk scenarios are still lacking. Further research is needed to determine the exact field of application of QFR, and whether it can supplant wire-based physiological indices remains a matter of debate.

Niels Ramsing Holm, MD; Birgitte Krogsgaard Andersen, MD

The evaluation of intermediate coronary stenosis remains a controversial topic due to multiple diagnostic pathways and numerous methods in clinical use. For patients reaching the cath lab, pressure wire-based evaluation is currently the gold standard, with some advantages over angiographic assessment. Still, the long-term outcome data supporting routine use...