Prognostic Values of Fractional Flow Reserve Based on Clinical Outcomes in Patients on Chronic Hemodialysis

The fractional flow reserve (FFR) cut-off values of 0.75 or 0.8 have been widely used; how-ever, whether they apply to patients on hemodialysis remains unknown. We aimed to investigate the cut-off value of FFR associated with clinical outcomes in patients on hemo-dialysis. Using the Japanese multicenter registry, we analyzed data of patients on hemodi-alysis with measured FFR between January 2010 and December 2016. Survival classification and regression tree analysis for the composite primary outcome of cardiovas-cular mortality, myocardial infarction, and target vessel revascularization revealed a threshold FFR of 0.83. Multivariate Cox regression analyses were performed for the clini-cal outcomes. Additionally, the primary outcome was analyzed using propensity score matching by dividing the patients into complete and incomplete revascularization groups according to the presence of residual lesions with an FFR of <= 0.83 after the intervention. Of the 212 included patients, 112 (52.8%) had lesions with an FFR of <= 0.83. After adjust-ing for confounders, an FFR of <= 0.83 was associated with a higher risk for the primary outcome (adjusted hazard ratio 2.01, 95% confidence interval 1.11 to 3.66, p = 0.021). Pro-pensity score matching showed that complete revascularization for lesions with an FFR of <= 0.83 was associated with a reduced risk for the primary outcome compared with incom-plete revascularization (hazard ratio 0.38, 95% confidence interval 0.20 to 0.71, log-rank p = 0.0016). In conclusion, an FFR of <= 0.83 was an independent predictor of clinical events in patients on hemodialysis. Furthermore, complete revascularization was associated with better clinical outcomes. Thus, this population may require a distinct FFR cut-off value. (c) 2023 Elsevier Inc. All rights reserved. (Am J Cardiol 2023;207:441-447)