ABSTRACT
INTRODUCTION Coronary angiography remains the “gold standard” for the diagnosis of epicardial coronary artery disease. However, precise quantification of lesions severity is limited because of the complex three-dimensional geometry of epicardial plaques. Moreover, coronary physiology and physiopathological effects of lesions cannot be determined.1-3 Accurate identification of both normal and diseased vessel segments is complicated by diffuse disease as well as by angiographic artefacts of contrast streaming, image foreshortening, and calcification. Bifurcation or ostial lesion locations may be obscured and difficult to assess by overlapping branch segments. Measurements of coronary pressure and flow provide complementary information to the anatomic characterization of coronary disease obtained by both angiographic and intravascular ultrasound examinations. In particular, fractional flow reserve (FFR) has been demonstrated to be a useful tool to easily and reliably assess lesions significance and physiopathology.4 FFR in the catheterization laboratory can facilitate timely and more objective decision making about therapy, especially in complex and difficult settings. Table 15.1 summarizes current recommendations for the application of physiologic measurements with FFR, and shows how its use in more complex settings is still under investigation.5 In this chapter, we describe the utility and limitations of this technique in particular complex situations, such as ostial location, bifurcation, tandem lesions, ectasic vessel, and in-stent restenosis (Table 15.1).
