Influence of the length of coronary artery lesions on fractional flow reserve across intermediate coronary obstruction

The aim of the study was to assess the effect of coronary lesion length (LL) on fractional flow reserve (FFR) in coronary arteries with intermediate diameter stenosis (DS; 30–60%). Eighty-three patients (89 lesions) with coronary artery disease underwent FFR measurement using a Radi or Volcano pressure wire. Diameter stenosis and LL were determined by quantitative coronary angiography, and the relationship between DS, LL, and FFR was assessed by regression analysis. Seventy-nine lesions had DS between 30 and 60% and were entered into the retrospective analysis. Mean DS and LL were 41.6 (±6.77%) and 9.2 (±6 mm), respectively. Fractional flow reserve ranged from 0.5 to 1.0. Pearson correlation coefficient for FFR vs. LL was 0.42 (P < 0.001). Using FFR = 0.8 as a cut-off point, there was no difference in mean DS between the two subgroups (42 vs. 41.5%, P = NS), while there was a significant difference in the LL (12.39 vs. 7.83 mm, P = 0.002). In intermediate coronary artery lesion, there is a strong inverse correlation between FFR and LL.