Clinical and angiographic factors predicting fractional flow reserve and explaining the visual–functional mismatch in patients with intermediate coronary artery stenosis

Abstract

Background Visual–functional mismatch between coronary angiography and fractional flow reserve (FFR) has been reported, and the underlying reason remains poorly understood. Therefore, the relationship between angiographic measurements and FFR was evaluated, and predictors for FFR in intermediate coronary artery stenosis were determined. Methods Consecutive 314 patients (405 lesions) with a lesion of 30–80% angiographic diameter stenosis who underwent invasive FFR were recruited. The myocardial area supplied by the coronary artery distal to the stenosis was evaluated using a modified version of the Bypass Angioplasty Revascularization Investigation (BARI) score. Participants underwent follow-up, and major cardiovascular events (MACE), including all-cause death, myocardial infarction (MI), and unplanned revascularization were recorded. Results Although % diameter stenosis was correlated with FFR (R = 0.279, P < 0.001), diameter stenosis-FFR mismatch was observed in 37.8% of the lesions. Although FFR values were not associated with clinical factors, such as age, sex, and comorbidities, it was correlated with minimal lumen diameter (MLD), diffuse lesion, presence of proximal lesion, and BARI score. In addition, the lesions in left anterior descending (LAD) coronary artery showed low FFR values compared with those in the left circumflex coronary artery or right coronary artery. In multivariate logistic analysis, MLD (β coefficient = 0.330), diffuse lesion (β coefficient = –0.266), proximal lesion (β coefficient = –0.144), BARI score (β coefficient = –0.219), and LAD lesion (β coefficient = –0.293) were all independent predictors for FFR value. The estimated FFR value based on these factors showed smaller mismatch and higher sensitivity. No difference was observed in the event rates for MACE and MI or revascularization between the FFR-guided and estimated FFR-guided strategies. Conclusions MLD, diffuse lesion, proximal lesion, BARI score, and lesion vessel were independent predictors for FFR in intermediate coronary stenosis. Not only the extent of local lesion stenosis but also the amount of myocardial supply and the lesion location may determine the physiological significance and explain the visual–functional mismatch. The estimation of FFR by these factors may be useful in clinical practice.

Determinants and prognostic implications of instantaneous wave-free ratio in patients with mild to intermediate coronary stenosis: Comparison with those of fractional flow reserve

“…The lesion characteristics, such as minimum lumen diameter, lesion location (LAD versus LCX or right coronary artery), diffuse lesion, proximal lesion, and BARI score FFR, was independently associated with FFR (fit of the model: R 2 = 0.536) [ 10 ]; those lesion characteristics was similarly associated with iFR (fit of the model: R 2 = 0.391). Hemoglobin A1c level was not associated with FFR independently with the multivariate analysis including the lesion characteristics ( p = 0.865).…”

“…CAG was performed with a standard technique involving the transradial or transfemoral approach [10]. Patients were administered intracoronary isosorbide dinitrate (1 to 5 mg) before initial angiography to achieve maximal vasodilation.…”

“…To evaluate the myocardial area supplied by the coronary artery distal to the stenosis, a modified version of the Bypass Angioplasty Revascularization Investigation (BARI) score was utilized, as in a previous study [10].…”

“…Watanabe et al recently reported that not only the extent of local stenosis but also the amount of myocardial supply and the lesion location determined the physiological significance and may explain the visual-functional mismatch between CAG and FFR in mild to intermediate coronary stenosis [10]. Therefore, we evaluated the relationship of iFR with FFR in detail, and we determined the predictors for iFR and its prognostic potentials in 323 consecutive patients with CAD and mild to intermediate coronary artery stenosis.…”

Three-Dimensional Angiographic Characteristics versus Functional Stenosis Severity in Fractional and Coronary Flow Reserve Discordance: A DEFINE FLOW Sub Study

“…The visual–functional mismatch between coronary angiography and FFR has been acknowledged in previous studies, showing a large dispersion of FFR values, especially in angiographic intermediate lesions [ 15 , 16 , 17 ]. This was confirmed by the present study for both FFR and CFR, as there was a poor correlation between visual DS and invasively assessed FFR and CFR values ( Figure 1 ).…”