Factors influencing the functional significance in intermediate coronary stenosis.

Objective: To analyze the influencing factors of the functional significance determined by fractional flow reserve (FFR) in intermediate coronary artery stenosis.

Methods: The study enrolled 143 patients with 203 intermediate coronary lesions. Pressure-derived FFR of these lesions was gained at maximal hyperemia induced by intravenous adenosine infusion. An FFR < 0.80 was considered as abnormal functional significance. Anatomic parameters at the lesion sites were obtained by off-line quantitative coronary angiography analysis (QCA). The predictive value of the demographic characteristics and anatomic parameters for FFR in these intermediate lesions was assessed using multiple linear and binary logistic regression analysis.

Results: Overall, FFR < 0.8 was found in 70 (34%) of the total 203 intermediate coronary lesions. FFR values were positively correlated with QCA-measured minimum lumen diameters (MLD, r = 0.372, P = 0.000) and the reference vessel diameters (RVD, r = 0.217, P = 0.002) were negatively correlated with percent area stenosis (AS, r = -0.251, P = 0.000) and percent diameter stenosis (DS, r = -0.210, P = 0.000). Age, MLD and the lesion location in different coronary arteries were the independent determinants of FFR < 0.8.

Conclusions: MLD can predict the functional significance of intermediate coronary stenosis, while age and the lesion location in different coronary arteries should be taken into account as important influencing factors of FFR values.