Angiography-Based Fractional Flow Reserve: State of the Art

Abstract

Purpose of Review Three-dimensional quantitative coronary angiography-based methods of fractional flow reserve (FFR) derivation have emerged as an appealing alternative to conventional pressure-wire-based physiological lesion assessment and have the potential to further extend the use of physiology in general. Here, we summarize the current evidence related to angiography-based FFR and perspectives on future developments. Recent Findings Growing evidence suggests good diagnostic performance of angiography-based FFR measurements, both in chronic and acute coronary syndromes, as well as in specific lesion subsets, such as long and calcified lesions, left main coronary stenosis, and bifurcations. More recently, promising results on the superiority of angiography-based FFR as compared to angiography-guided PCI have been published. Summary Currently available angiography -FFR indices proved to be an excellent alternative to invasive pressure wire-based FFR. Dedicated prospective outcome data comparing these indices to routine guideline recommended PCI including the use of FFR are eagerly awaited.

Performance of a novel artificial intelligence software developed to derive coronary fractional flow reserve values from diagnostic angiograms

“…Thereafter manual insertion of blood pressure as well as annotation of the target lesion and the surrounding vessel contour needs to be marked by catheterization laboratory (cath-lab) personnel, and only then CFD calculation will start. Total time for annotation and calculation takes between 3 and 5 min [ 17 ], for example, in the FAVOR III China study, the QFR calculation took an average 3.9 ± 1.4 min [ 21 ]. This complex process compromises user experience, wastes valuable Cath-lab time, increases training time and learning curve and may result in suboptimal reproducibility.…”

“…These angiogram-based techniques have specific procedural and post-procedural requirements as well as a relatively long calculation time. The operator needs to acquire specific 2–3 projections of each coronary vessels while table panning is forbidden, and the software requires manual marking of a specific blood vessel segment as well as manual input of aortic pressures; only then calculation begins and typically takes ~4–6 min [ 17 , 18 ].…”

Vessel fractional flow reserve-based non-culprit lesion reclassification in patients with ST-segment elevation myocardial infarction: Impact on treatment strategy and clinical outcome (FAST STEMI I study)

“…With a short analysis time (3.4 to 5.0 min on average), and no need for dedicated pressure wires, microcatheters and/or hyperemic agents, angiography-based FFR offers a unique opportunity for both acute-setting as well as offline physiological lesion assessment guiding complete revascularization or subsequent Heart Team discussion. [9,20] Out of the 498 patients meeting clinical entry criteria in our study, vFFR computation appeared not feasible in only 57 patients (11.4%), illustrating that vFFR is a suitable technique for physiological lesion assessment in the majority of patients, even in a study population with no specific focus on proper image acquisition for the purpose of angiography-based FFR.…”

Three-Year Clinical Impact of Murray Law-Based Quantitative Flow Ratio and OCT- or FFR-Guidance in Angiographically Intermediate Coronary Lesions

“…One of the main novelties in the field of coronary angiography interpretation is represented by the potential to process the acquired images and, using computational μQFR in OCT-and FFR-Guidance models, derive noninvasive evaluations of coronary physiology. 26,27 Such an approach has started to be evaluated in clinical trials, and we tested its potential in the context of the data collected in a prospective randomized trial focused on AICL. We confirmed the feasibility of μQFR evaluation in such a context and found a promising clinical signal since the only clinical predictor of 3-year TVF was post-μQFR for stented lesion (post-PCI OCT-derived parameters were not evaluated) and pre-μQFR for deferred lesions.…”