A Novel CT Perfusion-Based Fractional Flow Reserve Algorithm for Detecting Coronary Artery Disease

Area of Science:

• Cardiovascular Imaging
• Non-invasive Cardiac Diagnostics
• Computational Fluid Dynamics in Cardiology

Background:

• Diagnostic accuracy of fractional flow reserve derived from coronary computed tomography angiography (FFR-CT) requires improvement.
• An innovative myocardial computed tomographic perfusion-derived fractional flow reserve (CTP-FFR) model has been developed.
• The clinical feasibility of CTP-FFR for detecting coronary artery ischemia in suspected coronary artery disease (CAD) remains unproven.

Purpose of the Study:

• To evaluate the diagnostic performance of a novel CTP-FFR model in patients with suspected CAD.
• To compare the accuracy of CTP-FFR against CCTA, FFR-CT, and CTP.
• To assess the impact of lesion calcification on CTP-FFR measurements.

Main Methods:

• Retrospective study of 93 patients (103 vessels) with suspected CAD undergoing CCTA and CTP.
• Invasive coronary angiography (ICA) performed within 2 weeks as a reference standard.
• Independent assessment of CTP-FFR, CCTA (stenosis ≥50% and ≥70%), ICA, FFR-CT, and CTP; analysis of diagnostic ability across stenosis severity and calcification levels.

Main Results:

• CTP-FFR demonstrated superior diagnostic performance with an area under the curve (AUC) of 0.953, outperforming CTP (0.876), FFR-CT (0.873), and CCTA (0.830) (p < 0.001).
• CTP-FFR achieved high sensitivity (0.87) and specificity (0.88), with improved accuracy and AUC compared to CCTA and FFR-CT (p < 0.05).
• A strong correlation was observed between CTP-FFR and invasive FFR (r=0.89); specificity was higher in severe calcification groups.

Conclusions:

• The novel CTP-FFR model shows significant promise for detecting myocardial ischemia in CAD.
• CTP-FFR offers enhanced diagnostic value, particularly for mild-to-moderate coronary stenotic lesions.
• This non-invasive approach provides a valuable tool for assessing coronary artery stenosis severity and functional significance.