The reasons why fractional flow reserve and instantaneous wave-free ratio are similar using wave separation analysis

摘要

Changes in pressures before and after Hyperemia and wave free period extraction through WIA analysis. a Aortic and distal pressures (Pa, Pd), forward and backward waves (Pfor, Pback) in a cycle at pre-hyperemia and hyperemia, and horizontal lines are their average values over a cycle. Pa decreased little but Pd decreased more at hyperemia. Although overall Pback decreases a lot at hyperemia, there is little change in Pfor between pre-hyperemia and hyperemia. b Wave free period was extracted through wave intensity analysis (WIA) as shown in green boxes