The influence of side branch stenosis on fractional flow reserve assessment of the main branch in a swine model

Objectives The aim of this study was to explore the effect of one stenosis in a daughter artery on the fractional flow reserve (FFR) of another stenosis parallels in side branch. Background: The impact of one stenosis on the FFR of another parallel stenosis has not been evaluated. Methods: The proximal segments of the left anterior descending (LAD) and left circumflex (LCX) arteries were exposed and encircled with a Teflon pledget complex in seven swine (55–70 kg). Five degrees of stenosis (to approximate angiographic diameter stenoses of 0%, 25%, 50%, 75%, and 100%) were made by tightening the pledgets. FFR was evaluated simultaneously in the LAD and the LCX with two pressure wires in each coronary artery. A mixed-effects linear model was used to evaluate the association between the FFR values. Results: A total of 115 paired FFR values were obtained. The FFR of the LAD and LCX were not significantly associated with each other (F = 0.237 and P = 0.627 for the LCX FFR to predict the LAD FFR; F = 0.541 and P = 0.463 for the LAD FFR to predict the LCX FFR). Conclusions: The individual FFR values of each parallel stenosis in the LAD and the LCX were not significantly influenced by each other. This relationship was independent of the mean aortic pressure and heart rate. © 2016 Wiley Periodicals, Inc.