A significant pressure drop across a stenosis, indicated by a higher ratio of upstream to downstream pressure, correlated with worse outcomes in patients not receiving stenting in the FAME study.

“ffr evolved as a sort of hemodynamic way to be able to impute this severity of the stenosis and so I think Fame was the first of these studies and it showed that if you had a significant pressure drop um if the ratio of the pressure and the sort of Upstream sensor was was much you know higher than the uh Downstream sensor that that uh conveyed that there was a bad lesion and that it conveyed worse outcomes in people uh who didn't get stented”