Clinical Validation of a Virtual Planner for Coronary Interventions Based on Coronary CT Angiography

Background: Low fractional flow reserve (FFR) values after percutaneous coronary intervention (PCI) carry a worse prognosis than high post-PCI FFR values. Therefore, the ability to predict post-PCI FFR might play an important role in procedural planning. Post-PCI FFR values can now be computed from pre-PCI coronary computed tomography angiography (CTA) using the fractional flow reserve derived from coronary computed tomography angiography revascularization planner (FFR Planner).

Objectives: The aim of this study was to validate the accuracy of the FFR Planner.

Methods: In this multicenter, investigator-initiated, prospective study, patients with chronic coronary syndromes and significant lesions based on invasive FFR ≤0.80 were recruited. The FFR Planner was applied to the fractional flow reserve derived from coronary computed tomography angiography (FFR) model, simulating PCI. The primary objective was the agreement between the predicted post-PCI FFR by the FFR Planner and measured post-PCI FFR. Accuracy of the FFR Planner's luminal dimensions was assessed by using post-PCI optical coherence tomography as the reference.

Results: Overall, 259 patients were screened, with 120 patients (123 vessels) included in the final analysis. The mean patient age was 64 ± 9 years, and 24% had diabetes. Measured FFR post-PCI was 0.88 ± 0.06, and the FFR Planner FFR was 0.86 ± 0.06 (mean difference: 0.02 ± 0.07 FFR unit; limits of agreement: -0.12 to 0.15). Optical coherence tomography minimal stent area was 5.60 ± 2.01 mm, and FFR Planner minimal stent area was 5.0 ± 2.2 mm (mean difference: 0.66 ± 1.21 mm; limits of agreement: -1.7 to 3.0). The accuracy and precision of the FFR Planner remained high in cases with focal and diffuse disease and with low and high calcium burden.

Conclusions: The FFR-based technology was accurate and precise for predicting FFR after PCI. (Precise Percutaneous Coronary Intervention Plan Study [P3]; NCT03782688).