CORONARY ARTERY DISEASE (CAD);

INTERMEDIATE CAD WITH FFR (FRACTION FLOW RESERVE) EVALUATION

Abstract

Background: Coronary artery lesion severity is physiological assessed by
fractional myocardial flow reserve (FFR). Angiographic assessment of intermediate severity
lesions is problematic as inter-observer variability is significant. Hence one is not sure about
the hemodynamic or functional significance of these lesions. FFR is helpful in this situation
by assessing functional or hemodynamic significance of these intermediate coronary lesions.
An FFR value <0.80 identifies ischemia-causing coronary stenosis with an accuracy of >90%
suggesting that intermediate coronary lesion is in fact functionally important. Objective: To
determine the correlation between mean lesion length of diffuse intermediate stenosis (40%-
70% stenosis) of proximal and mid segment of major coronary arteries and mean fractional flow
reserve (FFR). Study duration: From 1-07-2015 to 31-12-2015. Study design: Cross sectional
study. Methodology: After approval from hospital Ethical committee and Informed consent, 60
patients with intermediate diffuse lesions on coronary angiography from Faisalabad Institute of
Cardiology were enrolled. FFR assessment of diffuse intermediate lesion was done by author.
FFR assessment was done using FFR wire during maximal blood flow (hyperemia) which
was induced by injecting bolus dose of intracoronary adenosine. The cost of procedure was
managed by hospital. Results: In this study, 28.33% (n=17) were between 20-50 years of age,
mean+SD was calculated as 55.17+8.04 years, 51.67% (n=31) were male and 48.33% (n=29)
were females. Correlation between mean lesion length of diffuse intermediate stenosis (40%-
70% stenosis) of proximal and mid segment of major coronary arteries and mean fractional
flow reserve (FFR) was recorded it shows that mean lesion length was 24.53+4.78 mm while
FFR was recorded as 0.72+0.12, the value of R is -0.1928, technically a negative correlation,
the relationship between variables is only weak (the nearer the value is to zero, the weaker
the relationship). The value of R2, the coefficient of determination, is 0.0372. Conclusion: The
correlation between mean lesion length of diffuse intermediate stenosis (40%-70% stenosis) of
proximal and mid segment of major coronary arteries and mean fractional flow reserve (FFR)
was weak and did not suggest any hemodynamic significance of diffuse intermediate coronary
artery lesions.