Terminology and Descriptions of the Index Abbreviations - Dr. Ricardo Petraco

Summary

Speaker: Dr Ricardo Petraco, Imperial College Healthcare NHS Trust, London

Ricardo Petraco discusses different physiological indices, and explains the derivation and methods for calculation of each index.

Key learning points:

• 1. Pd/Pa, FFR (Fractional Flow Reserve) , and iFR (Instantaneous Wave-free ration) are pressure-only indices measures using a ratio of the Pd (wire pressure) and Pa (aortic pressure)
• 2. Pd/Pa and FFR are measured across the entire cardiac cycle, typically using a moving average of 3-5 beats
• 3. iFR is measured over a phase in diastole, the Wave Free-period where resistance is low and most stable
• 4. CFR (Coronary Flow Reserve) is the ratio of mean basal flow by mean hyperaemic flow