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

Objectives: This study aimed to investigate the performance of computed tomography derived fractional flow reserve based interactive planner (FFRCT planner) to predict the physiological benefits of percutaneous coronary intervention (PCI) as defined by invasive post-PCI FFR. Background: Advances in FFRCT 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 FFRCT was calculated using pre-PCI coronary CT angiography. Subsequently, FFRCT and invasive coronary angiography models were aligned allowing virtual removal of coronary stenoses on pre-PCI FFRCT models in the same locations as PCI was performed. Relationships between invasive FFR and FFRCT, between post-PCI FFR and FFRCT planner, and between delta FFR and delta FFRCT were evaluated. Results: Pre PCI, invasive FFR was 0.65 ± 0.12 and FFRCT 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 FFRCT 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 FFRCT 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 FFRCT (r = 0.53, p <.001), between post-PCI FFR and FFRCT planner (r = 0.41, p =.001), and between delta FFR and delta FFRCT (r = 0.57, p <.001). Conclusions: The non-invasive FFRCT planner tool demonstrated significant albeit modest agreement with post-PCI FFR and change in FFR values after PCI. The FFRCT planner tool may hold promise for PCI procedural planning; however, improvement in technology is warranted before clinical application