Residual Quantitative Flow Ratio to Estimate Post‐Percutaneous Coronary Intervention Fractional Flow Reserve

Figure 1

Case example of residual QFR analysis. (a-b) Two end-diastolic frames of ICA in a patient with a proximal LAD lesion (FFR: 0.77). The stenosis was angiographically and functionally (post-PCI FFR: 0.96) successfully revascularized (c-d). During the QFR analysis, vessel contours were automatically detected on the two end-diastolic frames and manually corrected if needed (e). A 3D model of the coronary was reconstructed based on the vessels contours and lesions are presented as a drop in vessel diameter and QFR (g-f). The proximal and distal markers of the lesion in the QFR analysis were matched with the treated location during PCI to allow virtual removal of the lesion (c, f-g). Residual QFR was calculated by adding the delta QFR of the lesion to the vessel QFR (g). FFR: fractional flow reserve, ICA: invasive coronary angiography, LAD: left anterior descending artery, PCI: percutaneous coronary intervention, and QFR: quantitative flow ratio.