The effect of transcatheter aortic valve implantation on fractional flow reserve and non-hyperemic pressure ratios

Abstract Background Coronary artery disease in patients undergoing transcatheter aortic valve implantation (TAVI) is a very frequent clinical issue. Complex coronary artery disease can negatively influence outcomes after TAVI, however, angiography-guided percutaneous coronary intervention (PCI) has not been shown to offer any prognostic benefit. Coronary pressure indices, to select which lesions need treatment, are promising but are currently underused in aortic stenosis (AS) patients due to many physiological pitfalls. Available studies are small and show conflicting results on the effect of transcatheter aortic valve implantation (TAVI) on these indices. Purpose The aims is to compare the effects of TAVI on fractional flow reserve (FFR) and Non-hyperemic pressure ratio’s (NHPRs). Both immediate and long-term effects were studied. Methods Lesion specific coronary pressure data was extracted from 6 studies resulting in 147 lesions for immediate change in FFR analysis and 105 for NHPR analysis. To investigate the long-term changes, 93 lesions for FFR analysis and 68 for NHPR analysis were found. Results Immediately after TAVI, FFR decreased significantly (-0.0130 ± 0.0406 standard deviation, p-value: 0.0002) while NHPR remained stable (0.0003 ± 0.0675, p-value: 0.9675). Long-term after TAVR, FFR decreased significantly (-0.0230 ± 0.0747, p-value:0.0038) while NHPR increased non-significantly (0.0166 ± 0.0699, p-value: 0.0543). This increase in NHPRs became significant when only borderline NHPR lesions were considered (0.0249 ± 0.0441, p-value: 0.0015). All other results were confirmed in borderline-only lesions. Conclusions TAVI caused small significant, but opposite, changes in FFR and NHPR. In AS, FFR might underestimate lesion significance while NHPRs might overestimate its significance. This is only clinically relevant in borderline lesions, clear positive or negative physiological assessments can be trusted.Figure 1Figure 2