ABSTRACT
BACKGROUND AND OBJECTIVES: The purposes of this study are 1) to investigate the relationship between resting baseline Pd/Pa, determined by the ratio of the pressures proximal (Pa) and distal (Pd) to the target lesion before, inducing hyperemia and fractional flow reserve (FFR) and 2) to identify a resting baseline Pd/Pa range that might reliably preclude the need for hyperemic induction. SUBJECTS AND METHODS: A total of 622 pressure wire data sets obtained from intermediate stenotic lesions were analyzed. RESULTS: There was a good linear relationship between resting baseline Pd/Pa and FFR (r=0.746, p0.95 (n=257, 41.3%) had a negative predictive value (NPV) of 98.1% and a sensitivity of 97.3%. the resting baseline Pd/Pa < or =0.88 (n=65, 10.5%) had a positive predictive value (PPV) of 96.2% and a specificity of 99.8%. These were consistent regardless of coronary vessel, lesion location, lesion length, or degree of stenosis. CONCLUSION: In intermediate lesions, the resting baseline Pd/Pa was linearly related to FFR. A certain range of the resting baseline Pd/Pa values had an excellent NPV with high sensitivity or excellent PPV with high specificity for determining the lesion significance.