Fractional Flow Reserve and Intravascular Ultrasound in Evaluating Intermediate Coronary Lesions

Recent studies have shown that optimal IVUS criteria defining the functional significance (FFR \< 0.8) of intermediate coronary stenoses is different according to their locations of the coronary tree. Herein, the investigators performed this study to validate these results and to generalize the IVUS criteria defining functional significance of intermediate coronary stenosis in a different location of coronary tree in a larger sample size.