CORONARY ARTERY DISEASE Original Studies Expert Consensus Statement on the Use of Fractional Flow Reserve, Intravascular Ultrasound, and Optical Coherence Tomography: A Consensus Statement of the Society of Cardiovascular Angiography and Interventions

The rationale for use of intracoronary physiology assessment and imaging arises from the limitations of coronary angiography, the traditional method for determining the severity of coronary stenoses. The visual assessment of percent diameter reduction has significant interobserver variability [1–3], even among experienced angiographers [4]. Computer-assisted quantitative coronary angiography only marginally improves diagnostic accuracy and its estimate of functional significance [5]. Fractional flow reserve (FFR) is used to determine the functional significance of a coronary stenosis [6]. Intravascular ultrasound (IVUS) offers excellent visualization of intraluminal and transmural coronary anatomy. Optical coherence tomography (OCT) further improves vascular visualization. There is now persuasive evidence regarding intracoronary diagnostic lesion assessments using physiology and anatomy. These adjunctive diagnostic procedures may influence the decision for coronary revascularization, guide the performance of percutaneous coronary interventions (PCI), and optimize procedural outcomes. There are substantial long-term outcome data showing benefit associated with FFR-guided decision-making. However, these techniques are underutilized in contemporary practice: the rates of use of IVUS and FFR during PCI for intermediate coronary stenoses (40–70% diameter stenosis) are 20.3% and 6.1% respectively [7]. In 2011, the ACCF/AHA/SCAI PCI guidelines [8] assigned levels of evidence for the use of these modalities in various clinical situations (Table I). The purpose of this consensus statement is to review recent studies, to develop a consensus of how these