Fractional Flow Reserve and Fractional Flow Reserve Gradient From CCTA for Predicting Future Coronary Events.

Area of Science:

• Cardiovascular Imaging
• Interventional Cardiology
• Computational Fluid Dynamics

Background:

• Coronary computed tomography angiography-derived fractional flow reserve (FFR_CT) assesses cumulative hemodynamic burden per vessel.
• Coronary events often manifest at focal lesions, suggesting limitations of a per-vessel cumulative index alone.

Purpose of the Study:

• To evaluate the additive prognostic value of the FFR_CT gradient, a local hemodynamic measure, beyond FFR_CT for predicting future coronary events.
• To determine if FFR_CT gradient improves risk stratification in coronary artery disease.

Main Methods:

• A cohort of 245 patients (634 vessels) with prior coronary computed tomography angiography was analyzed.
• Future coronary events (myocardial infarction or urgent revascularization) were tracked over a mean of 1.5 years.
• FFR_CT ≤0.80 and FFR_CT gradient ≥0.025/mm were used to classify disease patterns.

Main Results:

• Both FFR_CT and FFR_CT gradient were significant predictors of future coronary events (P < 0.001).
• High FFR_CT gradient (≥0.025/mm) identified increased risk regardless of FFR_CT value.
• Integrating FFR_CT gradient into models with FFR_CT alone significantly improved the prediction of future coronary events (P = 0.015).

Conclusions:

• FFR_CT gradient provides crucial prognostic information for coronary artery disease, independent of FFR_CT.
• The combination of FFR_CT and FFR_CT gradient offers enhanced predictability of future coronary events.
• This suggests FFR_CT gradient is a valuable addition to non-invasive hemodynamic assessment in coronary artery disease.