Diagnostic value of the fractional flow reserve: attention, blood rheology!

Assessment of hemodynamic significance of coronary artery stenosis has become crucial in determining the treatment strategy for coronary artery disease (CAD). Consequently, invasive methods for evaluating the functional significance of stenosis have become widely used. Additionally, diagnostic technologies that combine coronary angiography and mathematical modeling of coronary flow have also been employed for this purpose. This paper presents an analytical review of the assessment of the functional significance of coronary artery stenosis using the fractional flow reserve (FFR) method. The review covers the fundamental aspects of the FFR method, its practical application, and its diagnostic value. Significant attention is given to blood rheology, particularly dynamic viscosity. Since dynamic viscosity is a key determinant of hemodynamic resistance to blood flow, especially in microcirculation, this factor can influence the interpretation of the results in coronary stenosis assessment.