The impact of multiple vessel disease on fractional flow reserve

Background - Fractional flow reserve (FFR) is a method for the assessment of intermediate lesions. The impact of lesions at other coronary arteries on the FFR is not clear. We aimed to investigate the impact of the lesions in the other coronary arteries on FFR measurement. Method - FFR was performed in 113 patients with intermediate lesions at the left anterior descending artery. FFR values at baseline (FFRbase) and after adenosine administration (FFRmin) were cletected. We divided the patients into groups according to FFRmin value. The first group consisted of 52 patients with a FFR < 0.80 and the second group consisted of 61 patients with a FFR >= 0.80. We investigated the relationship between Gensini score and FFR values within the groups. Results - A significant negative correlation was found in the analysis comparing Gensini score with FFRbase and FFRmin among the first group (r = -0.248, P = 0.009 and r = -0.685, P < 0.001, respectively). The relative FFR ratio was also significantly related with the Gensini score in the first group (r = -210, P = 0.047). When we divided the patients into 3 subgroups according to the number of the coronary arteries with significant lesion (>= 70% stenosis) (group I: 1 vessel, group II: 2 vessels, group III: 3 vessels), we observed a relation with FFRbase (0.89 +/- 0.05 vs. 0.87 +/- 0.06 vs. 0.81 +/- 0.09, respectively, P = 0.007) and FFRmin (0.76 +/- 0.04 vs. 0.75 +/- 0.05 vs. 0.68 +/- 0.1 respectively, P = 0.002). In the second group, there was no relationship between Gensini score, FFR values and number of significantly diseased vessels. Conclusion - The overall extent and severity of coronary artery disease in a patient may affect the FFR measurement and may lead to misinterpretation of the lesion severity.