Impact of the lesion location on fractional flow reserve

Fractional flow reserve (FFR) is a method to determine the significance of a lesion. Although an FFR measurement of < 0.75 is accepted to show ischaemia, the effect of the location of the lesion on the coronary artery is not known. This study investigates the effect of lesion location on the FFR measurement.

Ninety-nine eligible patients who had undergone FFR measurement of an intermediate lesion (40-70% stenosis) at the left anterior descending coronary artery (LAD) were included. The lesions proximal to the origin of the first diagonal branch were accepted as proximal lesions and the remaining lesions were accepted as distal.The patients were categorized according to the degree of the percent diameter stenosis (40-50%, 50-60%, and > 60%) and the reference vessel diameter (RVD) (> or = 2.8 mm and < 2.8 mm). We compared the FFR measurements between proximal and distal lesions among different categories which were set according to anatomical features of the lesions.

No significant difference was found between the FFR values of proximal and distal lesions with a similar percent diameter stenosis (0.86 +/- 0.08 vs. 0.83 +/- 0.08; 0.77 +/- 0.11 vs. 0.80 +/- 0.09; 0.75 +/- 0.07 vs. 0.77 +/- 0.08; P = 0.646).We did not find a difference between the FFR values of proximal and distal lesions with a similar RVD either (0.78 +/- 0.03 vs. 0.81 +/- 0.02; 0.84 +/- 0.03 vs. 0.81 +/- 0.01; P = 0.976). Major adverse cardiac event incidence was also similar for proximal and distal lesions (23% vs. 20%; P = 0.793).

Fractional flow reserve can show the physiological significance of a stenosis independent of the anatomical location of the lesion on the coronary artery.