Impact of coronary CT image quality on the accuracy of the FFRCT Planner

Abstract

Abstract Funding Acknowledgements Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The study was sponsored by the Cardiac Research Institute Aalst (Aalst, Belgium) with unrestricted grants from HeartFlow (Redwood City, California, USA) and CardioPath (University of Naples, Naples, Italy). Aims To assess the accuracy of a virtual stenting tool based on coronary CT angiography (CCTA) and fractional flow reserve (FFR) coronary derived from CCTA (FFRCT Planner) across different levels of image quality. Methods and results Prospective, controlled, multicenter, single-arm study of patients with chronic coronary syndromes and significant lesions based on invasive FFR ≤0.80. All patients underwent clinically indicated CCTA performed with recent generation scanners. CCTA image quality was adjudicated using the four-point Likert scale at per-vessel level by an independent committee blinded to the results of the FFRCT Planner. The FFRCT Planner was applied mirroring the percutaneous coronary intervention (PCI) to determine the agreement with invasively measured post-PCI FFR. Overall, 120 patients (123 vessels) were included. Mean age was 64.0±9.2 years, 27% were diabetics. Invasive post-PCI FFR was 0.88±0.06 and Planner FFRCT was 0.86±0.06 (mean difference 0.02 FFR units, LLA −0.12, ULA 0.15). CCTA image quality was assessed as excellent (Likert score 4) in 48.3%, good (Likert score 3) in 45% and sufficient (Likert score 2) in 6.7% of patients. The FFRCT Planner was accurate across the different levels of image quality with a mean difference between FFRCT Planner and invasive post-PCI FFR of 0.02±0.07 in Likert score 4, 0.02±0.07 in Likert score 3 and 0.03±0.08 in Likert score 2, p = 0.695. Conclusion The FFRCT Planner was accurate to predict post-PCI FFR independent of CCTA image quality.