Abstract 19676: Diagnostic Performance of Instantaneous Wave-Free Ratio for Intermediate Coronary Artery Stenosis in Patients With Severe Aortic Valve Stenosis
Introduction: Fractional flow reserve (FFR) is a standard technique to assess the functional severity of coronary artery stenosis in the catheterization laboratory, whereas the instantaneous wave-free ratio (iFR) is being introduced as a new non-pharmacologic-stress index of coronary stenosis severity. The iFR could have great advantages in patients with severe aortic valve stenosis (AS), to evaluate physiologically intermediate coronary artery stenosis, because iFR measurement does not require pharmacologic stress test. However, its performance has not been explored yet.
Hypothesis: The hypothesis and aims of this research is to establish best cut off iFR value for FFR ≤0.8 in intermediate coronary artery stenosis in patients with severe AS.
Methods: This clinical research launched from Feb 2015. This data was prospectively obtained from multicenter registry and interstitial review board approved in each center. Severe AS was defined an aortic valve area less than 1.0 cm2, a mean aortic valve gradient of 40 mm Hg or more, or a peak aortic jet velocity of 4.0 m/s or more. We compared iFR with FFR in intermediate coronary artery stenosis in patients with severe AS.
Results: We examined initial consecutive 45 patients (28 females, 57 intermediate coronary artery stenosis vessels). Mean iFR was 0.82 ± 0.18 and FFR was 0.82 ± 0.13. The iFR was well correlated with FFR (r = 0.862, p <0.001). ROC analysis demonstrated cut off iFR value for FFR ≤0.8 was 0.78 (AUC=0.851).
Conclusions: In sever AS patients with intermediate coronary artery stenosis, there is good correlation between iFR and FFR. The iFR measurement could be useful to detect a physiologically significant coronary artery stenosis in AS patients.
Author Disclosures: F. Yamanaka: None. K. Shishido: None. T. Ochiai: None. K. Yamazaki: None. N. Moriyama: None. S. Yamazaki: None. S. Saito: None.
- © 2016 by American Heart Association, Inc.