Trans-lesional fractional flow reserve gradient as derived from coronary CT improves patient management: ADVANCE registry

Abstract

Background: The role of change in fractional flow reserve derived from CT (FFR CT ) across coronary stenoses (ΔFFR CT ) in guiding downstream testing in patients with stable coronary artery disease (CAD) is unknown. Objectives: To investigate the incremental value of ΔFFR CT in predicting early revascularization and improving efficiency of catheter laboratory utilization. Materials: Patients with CAD on coronary CT angiography (CCTA) were enrolled in an international multicenter registry. Stenosis severity was assessed as per CAD-Reporting and Data System (CAD-RADS), and lesion-specific FFR CT was measured 2 cm distal to stenosis. ΔFFR CT was manually measured as the difference of FFR CT across visible stenosis.

Diagnostic Performance of Angiography-Derived Quantitative Flow Ratio in Complex Coronary Lesions

“…These results suggest potential limitations inherent in the binary interpretation of the FFR, leading to potential misinterpretations around the decision threshold. 27 Integrating the pressure loss across individual lesions may offer a promising approach for identifying ischemia within this ambiguous region 28 and merits further exploration.…”

Identification of ischemia-causing lesions using coronary plaque quantification and changes in fractional flow reserve derived from computed tomography across the lesion

“…The value of FFR CT was measured within 2 cm distal to the lesion plaque, which was colocalized with the invasive FFR. ΔFFR CT was defined as the change in the FFR CT across the lesion by computing the difference between the proximal and distal FFR CT values as follows (9)(10)(11): ΔFFR CT = proximal FFR CT − distal FFR CT . To assess the reproducibility between the observers, 2 experienced radiologists measured the ΔFFR CT of 30 consecutive vessels without knowledge of the patients' conditions.…”

“…Compared to the computational fluid dynamics method, machinelearning (ML)-based FFR CT requires less computation time and power and has been proven to have good diagnostic performance (7,8). Recently, studies have found that the change in FFR CT across the lesion (ΔFFR CT ) has higher diagnostic performance than FFR CT distal to the lesion and can improve patient management (9)(10)(11). The assessment of plaque characteristics based on CCTA is comparable to that of intravascular ultrasonography (IVUS) (12), and a previous study (6) showed that the former is related to the presence of ischemia.…”

CAD-RADS™ 2.0 - 2022 Coronary Artery Disease-Reporting and Data System

“…Given the non-binary nature of CT-FFR, current clinical guidance emphasizes that the CT-FFR value 1-2 cm distal to an area of coronary stenosis should be considered to guide decisions around referral to invasive angiographic and revascularization. 50 The lowest overall value along the entire vessel may be informative but typically reflects total plaque burden and the ratio of coronary volume to mass, and hence reflects vascular health, as a result it can be used to inform medical management but should not be used to guide catheterization laboratory referral. 51 To that end, current evidence suggests possible ICA referral for a symptomatic patient in the setting of an appropriate clinical context for coronary revascularization and the designation of "Iþ" (positive ischemia) for a lesion-specific value 0.75 in a vessel large enough for percutaneous Table 6 Interpretation of CT-FFR.…”

“…For values between 0.76 and 0.80 the modifier "Iþ/¡" (borderline or indeterminate value) is used and decisions around ICA referral will further depend on lesion location, symptom severity and delta CT-FFR (trans-lesional gradient >0.12 considered significant) as measured as the pressure loss from 1 to 2 cm proximal to 1-2 cm distal to a stenosis. 52 For lesions with an abnormal CT-FFR without a concordant anatomic lesion, the modifier "I-" should be described in case the reader is confident that this is false-positive result by CT-FFR or "Iþ/¡" if it is indeterminate and there is questionable interpretation of both findings. In multivessel disease the physiologically significant lesion may not be the most anatomically severe.…”