For many years, coronary angiography has been considered "the gold standard" for evaluating patients with coronary artery disease. However, angiography only provides a planar two-dimensional silhouette of the lumen and is unsuitable for the precise assessment of atherosclerosis. With the introduction of intravascular imaging, direct visualization of the arterial wall is now feasible. Intravascular imaging modalities extend diagnostic information, thereby enabling more precise evaluation of plaque burden and vessel remodeling. Of all technologies, intravascular ultrasound (IVUS) is the most mature and widely used intravascular imaging technique. Optical coherence tomography (OCT) is an evolving technology that has the highest spatial resolution of existing imaging methods, and it is becoming increasingly widespread. These methods are useful tools for planning interventional strategies and optimizing stent deployment, particularly when stenting complex lesions. We strongly support the mandatory use of IVUS for left main percutaneous coronary intervention (PCI). In addition, it can be used to evaluate vascular responses, including neointimal growth and strut apposition, during follow-ups. Adequately powered randomized trials are needed to support IVUS or OCT use in routine clinical practice and to answer whether OCT is superior to IVUS in reducing adverse events when used to guide PCI. The current perception and adoption of innovative interventional devices, such as bioabsorbable scaffolds, will increase the need for intravascular imaging in the future.
Keywords: Imaging; Optical coherence tomography; Restenosis; Stent; Thrombosis; Ultrasonics.