FFR (Fractional Flow Reserve) and iFR (Instantaneous Wave- Free Ratio) are knowned  technolgies used to mesure the patient stenosis. Recent investigation indicates that results achieved by iFR has better results when compared to FFR since it is a cut down on time, cost, operation complexity of the procedure. Moreover it will eliminate the use of adenosine to stimulate hyperaemia indicates the results presented in San Francisco in the United States during the TCT (Transcatheter Cardiovasluar Therapeutics) exhibition.

The article published by Dr Sen an concludes ” Intracoronary resistance is naturally constant and minimized during the wave-free period. The instantaneous wave-free ratio calculated over this period produces a drug-free index of stenosis severity comparable to FFR. (Vasodilator Free Measure of Fractional Flow Reserve”

It is to note that This study was supported by the Volcano Corporation..