How is FFR used during PTCA?
In recent studies (7,9,11), it has been determined that the diagnostic FFRmyo cut-off point is 0.75 and that FFRmyo = 1.0 is associated with a normal coronary artery (9). Exercise Testing was used as a gold standard to indicate or exclude inducible ischemia and to determine the ranges of FFRmyo indicating or excluding significant coronary artery disease. There was only a minimal overlap between normal and “pathological values, and the cut-off point was 0.74. Note that in most patients, after successful PTCA, FFRmyo did not completely return to normal values but was sufficient to prevent inducible ischemia. The average FFRmyo after PTCA was 0.88 0.07. FFRmyo in 33 coronary arteries in 8 normal patients equaled 0.98 0.03. The value of FFRmyo associated with a normal coronary artery is then 1.0. Experience to date would suggest that FFRmyo result of > 0.90 is an excellent PTCA result. FFRmyo < 0.90 would support a clinical decision to proceed with stent implantation. These values are unde
