Optical coherence tomography

Optical coherence tomography (OCT) is a light-based imaging modality which shows tremendous potential in the setting of coronary imaging. Compared to intravascular ultrasound (IVUS), OCT has a ten-fold higher image resolution. OCT has the ability to characterise the structure and extent of coronary artery disease in unprecedented detail as the various components of atherosclerotic plaques have different optical properties. Typically, calcified, fibrous and lipid-rich plaque components can be distinguished, as well as the presence of dense macrophage infiltration, neovascularisation and mural or intraluminal thrombi. These diagnostic capabilities are being applied to study patients with ACS and STEMI in order to improve our understanding of the pathophysiology and progression of atherosclerosis. Likewise, OCT allows the detailed analysis of coronary stents, their interaction with the vessel wall and their long-term outcome. In daily clinical practices, OCT may be efficient in complex interventions. Preliminary data indicates that OCT can change the operator’s intention-to-treat and modify the overall revascularisation strategy, potentially avoiding unnecessary interventional procedures. Recent studies shed light on the role of OCT as an instrumental tool to study plaque composition, particularly the extension of calcific components and select the most appropriate interventional device. This burden of information can ameliorate stent deployment and improve clinical outcome after coronary interventions. As such, OCT may emerge, along with its undisputed position in research, as the tool of choice in all clinical scenarios where angiography is limited by its nature as a two-dimensional luminogram.