Performance and 12-month Outcomes of a Wire-free Fractional Flow Reserve System for Assessment of Coronary Artery Disease

Background: Fractional flow reserve (FFR) using an invasive pressure wire is recommended to guide coronary revascularisation in stable coronary artery disease. Coronary angiography-based wire-free FFR (CAFFR) determines the significance of a coronary lesion without the requirement of a pressure wire. Deferral of revascularisation of coronary lesions with an FFR >0.8 has been shown to have similar outcomes to patients managed with optimal medical therapy. Objective: The aim of our study was to assess the performance and 12-month clinical outcomes in patients with CAFFR-guided percutaneous coronary intervention (PCI) deferral. Methods: This was a prospective study involving 69 patients (93 vessels) with angiographic stenosis of 30–90%. Patients with CAFFR ≤0.80 or poor image quality were excluded, leaving 29 patients (31 vessels) for analysis. All recruited patients had a CAFFR >0.80 and thus, PCI deferral. This cohort was followed up for 12 months. The primary endpoint was a composite of death from any cause, MI or target vessel revascularisation. Wired FFR was done for comparison on 14 patients (48%) at the operator’s discretion. Results: The mean age was 59.9 (±12.6) years. The majority of patients were men (83%; n=24), 41% (n=12) had diabetes, 62% (n=18) had hypertension, 59% (n=17) had dyslipidaemia, 62% (n=18) had a history of smoking. The mean left ventricular ejection fraction (LVEF) was 52 (±11.4)% and 76% of the patients had a recent acute coronary syndrome. We assessed the left anterior descending artery and 52% (n=16) of vessels had a mean CAFFR was 0.87. At 12 months, all patients were alive, 89.7% remained in chronic coronary syndrome (CCS) class 1 and 3.4% (n=1) of the study population met the primary outcome of target vessel revascularisation. Conclusion: CAFFR showed good agreement with wire-based FFR and 12-month outcomes showed that CAFFR-guided deferral of PCI was safe and comparable to wired-based FFR guidance.