Non-invasive procedural planning using computed tomography-derived fractional flow reserve

Abstract

Objectives: This study aimed to investigate the performance of computed tomography derived fractional flow reserve based interactive planner (FFR_CT planner) to predict the physiological benefits of percutaneous coronary intervention (PCI) as defined by invasive post-PCI FFR.

Background: Advances in FFR_CT technology have enabled the simulation of hyperemic pressure changes after virtual removal of stenoses.

Methods: In 56 patients (63 vessels) invasive FFR measurements before and after PCI were obtained and FFR_CT was calculated using pre-PCI coronary CT angiography. Subsequently, FFR_CT and invasive coronary angiography models were aligned allowing virtual removal of coronary stenoses on pre-PCI FFR_CT models in the same locations as PCI was performed. Relationships between invasive FFR and FFR_CT , between post-PCI FFR and FFR_CT planner, and between delta FFR and delta FFR_CT were evaluated.

Results: Pre PCI, invasive FFR was 0.65 ± 0.12 and FFR_CT was 0.64 ± 0.13 (p = .34) with a mean difference of 0.015 (95% CI: -0.23-0.26). Post-PCI invasive FFR was 0.89 ± 0.07 and FFR_CT planner was 0.85 ± 0.07 (p < .001) with a mean difference of 0.040 (95% CI: -0.10-0.18). Delta invasive FFR and delta FFR_CT were 0.23 ± 0.12 and 0.21 ± 0.12 (p = .09) with a mean difference of 0.025 (95% CI: -0.20-0.25). Significant correlations were found between pre-PCI FFR and FFR_CT (r = 0.53, p < .001), between post-PCI FFR and FFR_CT planner (r = 0.41, p = .001), and between delta FFR and delta FFR_CT (r = 0.57, p < .001).

Conclusions: The non-invasive FFR_CT planner tool demonstrated significant albeit modest agreement with post-PCI FFR and change in FFR values after PCI. The FFR_CT planner tool may hold promise for PCI procedural planning; however, improvement in technology is warranted before clinical application.

Keywords: computed tomography derived fractional flow reserve; coronary artery disease; coronary computed tomography angiography; fractional flow reserve; percutaneous coronary intervention.