COMPARATIVE ANALYSIS OF CONTRAST-INDUCED DIASTOLIC HYPEREMIA-FREE RATIO (CONTRAST-DFR) WITHFRACTIONAL FLOW RESERVE (FFR) AND DIASTOLIC HYPEREMIA-FREE RATIO (DFR)

Background

Fractional Flow Reserve (FFR) is the gold standard for assessing the functional significance of intermediate coronary artery stenosis.

Aim

To assess the diagnostic accuracy of Diastolic Hyperemia-Free Ratio (DFR), contrast-DFR, post- adenosine DFR, and Fractional Flow Reserve (FFR) for evaluating intermediate coronary artery stenosis.

Methods

We enrolled 45 consecutive patients with 48 intermediate lesions. After intravenous adenosine infusion, maximal hyperemia was achieved, and FFR and post- adenosine DFR measurements were obtained.

A single contrast medium injection of 6 ml (3 ml/s) was performed, and a Contrast DFR was measured within 10 seconds of injection, and lesions with a value of ≤ 0.80 were classified as hemodynamically significant.

Abnormal DFR was defined as a cutoff value of 0.89, Contrast DFR and post-adenosine DFR as a cutoff value of 0.80, and FFR as a cutoff value of 0.80.

Results

Diastolic Hyperemia-Free Ratio (DFR) was identified as hemodynamically significant in 33%, Contrast DFR as hemodynamically significant in 34%, and Post adenosine DFR as hemodynamically significant in 36%. The FFR was identified as hemodynamically significant in 19%.

A positive correlation between FFR and contrast DFR values was detected (r=0.79), a correlation of DFR versus FFR (r=0.76), and a correlation of post-adenosine DFR versus FFR (r=0.93).

Post-adenosine DFR identified a 12% higher prevalence of hemodynamically significant lesions compared to FFR.

Conclusion

This study demonstrates that contrast-induced Diastolic Hyperemia-Free Ratio (Contrast-DFR) measurement is a feasible alternative to FFR evaluation. Contrast-DFR has the potential to provide a further understanding of the functional severity of hemodynamically significant lesions.