Optimizing the Technique for Invasive Fractional Flow Reserve to Assess Lesion-Specific Ischemia.
Circ Cardiovasc Interv
Background: Invasive fractional flow reserve (FFRINV) is the standard technique for assessing myocardial ischemia. Pressure distortions and measurement location may influence FFRINV interpretation. We report a technique for performing invasive fractional flow reserve (FFRINV) by minimizing pressure distortions and identifying the proper location to measure FFRINV.
Methods: FFRINV recordings were obtained prospectively during manual hyperemic pullback in 100 normal and diseased coronary arteries with single stenosis, using 4 measurements from the terminal vessel, distal-to-the-lesion, proximal vessel, and guiding catheter. FFRINV profiles were developed by plotting FFRINV values (y-axis) and site of measurement (x-axis), stratified by stenosis severity. FFRINV≤0.8 was considered positive for lesion-specific ischemia.
Results: Erroneous FFRINV values were observed in 10% of vessels because of aortic pressure distortion and in 21% because of distal pressure drift; these were corrected by disengagement of the guiding catheter and re-equalization of distal pressure/aortic pressure, respectively. There were significant declines in FFRINV from the proximal to the terminal vessel in normal and stenotic coronary arteries (PP
Conclusions: Meticulous technique (disengagement of the guiding catheter, FFRINV pullback) is required to avoid erroneous FFRINV, which occur in 31% of vessels. Even with optimal technique, FFRINV values are influenced by stenosis severity and the site of pressure measurement. FFRINV values from the terminal vessel may overestimate lesion-specific ischemia, leading to unnecessary revascularization.
Renard BM, Cami E, Jiddou-Patros MR, Said A, Kado H, Trivax J, Berman A, Gulati A, Rabah M, Timmis S, Shoukfeh M, Abbas AE, Hanzel G, Hanson I, Dixon S, Safian RD. Optimizing the Technique for Invasive Fractional Flow Reserve to Assess Lesion-Specific Ischemia. Circ Cardiovasc Interv. 2019 Oct;12(10):e007939. doi: 10.1161/CIRCINTERVENTIONS.119.007939. Epub 2019 Oct 14. PMID: 31607155.