Correlation of early diastolic velocities and fractional flow reserve in intermediate coronary artery disease
Background: Fractional Flow Reserve (FFR) is an index of physiological significance of a coronary stenosis and is defined as the ratio of maximal blood flow in a stenotic artery to normal maximal flow. The severity of diastolic dysfunction may affect coronary blood flow, which may interfere with the coronary pressure as measured by the FFR. If there is an inverse relationship between the FFR and early diastolic velocity, then there might be an overestimation of the FFR values that could significantly affect the management of patients with intermediate coronary artery disease. This study aims to determine the relationship of early diastolic velocity as measured by Tissue Doppler Imaging and the Fractional Flow Reserve in intermediate coronary artery disease.
Methods: The research design was a retrospective, cross-sectional chart review. Medical records of subjects who underwent catheterization at St. Luke’s Medical Center from January 2011 to September 2014 were reviewed. Measurements of FFR and Early Diastolic Velocity were analyzed using Pearson r product moment correlation and simple linear regression.
Results: A total of 76 patients who underwent FFR determination were included. The
mean FFR was recorded at 0.86 with standard deviation of 0.11. There was an inverse correlation between Early Diastolic Velocity and Fractional Flow Reserve (r= -0.143, p= 0.547). However, the relationship was not statistically significant.
Conclusion: There is a weak inverse correlation between FFR and Early Diastolic Velocity. Further analysis using a larger sample size is recommended.