Abstract
Although angiography is the technique most interventional cardiologists use to assess the severity of coronary artery disease and guide treatment, conventional angiography has some limitations such as providing a 2D silhouette of the arterial lumen so images may be foreshortened, not depicting plaque characteristics or burden, features of arterial wall structure. With those realities in mind, intravascular imaging modalities emerged including intravascular ultrasound (IVUS), optical coherence tomography (OCT), and near-infrared spectroscopy (NIRS). These techniques provide cross-sectional images of the coronary artery including lumen, wall, plaque burden, plaque composition and distribution, and even structures around the vessel – information that is promised but rarely delivered by angiography. Intravascular imaging (IVI) can be used to answer questions that arise in daily practice as well as follow-up results such as: How severe is this stenosis? What is the culprit lesion? What is the appropriate stent size and length? What is the risk of distal embolization or peri-procedural MI during stenting? Has the intervention been optimized? Why did this stent thrombose or restenose? This article summarizes the applications of intravascular imaging techniques from the past to present as well as data on incorporating them into routine clinical practice and future directions.
