Comparison of predicted post-PCI FFR derived from coronary computed tomography angiography versus observed...

Fractional flow reserve (FFR) derived from coronary computed tomography angiography (FFR_CT) facilitates virtual PCI planning and informs stent length selection based on predicted post-PCI FFR_CT. This approach was previously validated against pressure-wire based FFR. Whether angiographic FFR can be used to ascertain the target post-PCI FFR_CT predicted from CCTA is uncertain.

Observational cohort study of patients undergoing coronary computed tomography angiography (CCTA) with an FFR_CT ≤ 0.80 that were referred to CCTA-guided PCI using the FFR_CT-based virtual planner (HeartFlow Inc.) for pre-procedural guidance and FFR_angio (CathWorks Ltd.) for intra- and post-procedural assessment. Virtual FFR pullbacks (FFR measurements every 1 mm across the vessel length) were analyzed and compared for both FFR_CT and FFR_angio modalities. We evaluated the agreement between pre- and post-PCI FFR_CT and FFR_angio at matched locations using the Pearson correlation coefficient and Bland-Altman analysis. Virtual FFR pullbacks (FFR measurements every 1 mm across the vessel length) were analyzed and compared for both FFR_CT and FFR_angio modalities.

A total of 2290 post-PCI FFR values were derived from 20 vessels that underwent CCTA-guided PCI virtual PCI followed by post-PCI FFR_angio. FFR values were matched across FFR pullback tracings that allowed the comparison of predicted post-PCI FFR_CT to observed post PCI FFR_angio results. The left anterior descending artery (LAD) (45 %) was the most common target vessel. A strong correlation was observed between FFR_CT and FFR_angio (R = 0.74; p < 0.001). The mean difference at matched locations was -0. 01 FFR units, with a standard deviation of 0.04 and limits of agreement ranging from -0.10 to 0.07.

Predicted post-PCI FFR_CT values derived from CCTA-based virtual PCI have an excellent correlation with observed post-PCI FFRangio values derived from invasive coronary angiography after stenting. These findings highlight the novel concept of wireless end-to-end physiology guided PCI, integrating pre-PCI FFR_CT and post-PCI angiographic FFR as complementary tools.