Clinical Molecular Imaging for Atherosclerotic Plaque

Abstract

Atherosclerosis is a well-known disease leading to cardiovascular events, including myocardial infarction and ischemic stroke. These conditions lead to a high mortality rate, which explains the interest in their prevention, early detection, and treatment. Molecular imaging is able to shed light on the basic pathophysiological processes, such as inflammation, that cause the progression and instability of plaque. The most common radiotracers used in clinical practice can detect increased energy metabolism (FDG), macrophage number (somatostatin receptor imaging), the intensity of cell proliferation in the area (labeled choline), and microcalcifications (fluoride imaging). These radiopharmaceuticals, especially FDG and labeled sodium fluoride, can predict cardiovascular events. The limitations of molecular imaging in atherosclerosis include low uptake of highly specific tracers, possible overlap with other diseases of the vessel wall, and specific features of certain tracers’ physiological distribution. A common protocol for patient preparation, data acquisition, and quantification is needed in the area of atherosclerosis imaging research.

Early Assessment of Atherosclerotic Lesions and Vulnerable Plaques in vivo by Targeting Apoptotic Macrophages with AV Nanobubbles

“…Many research reported different imaging modalities for identification and visualization of AS lesions or plaque vulnerability, 19,43 such as micro-CT imaging, 44 intravascular ultrasound (IVUS) imaging, 45 optical coherence tomography (OCT) imaging, 46 contrast-enhanced MRI, 47 as well as CEUS. [48][49][50] However, these researches mainly focused on monitoring the outcomes of plaque formation, such as assessment of plaque neovascularization, macrophage distribution, vascular plaque burden and atherosclerotic plaque composition.…”

“…Currently, molecular imaging can show specific biological pathways or cellular processes for a better understanding of the molecular events responsible for plaque destabilization. 19,20 Ultrasound molecular imaging technology presented great potentials to characterize and image the occurrence and development of diseases on the molecular level. [21][22][23] In particular, the development of a wide range of imaging contrast agents, functionalized with targeting ligands such as antibodies, peptides or aptamers, 24,25 could be promising for probing the molecular biomarkers of the atherosclerotic processes, promoting the translational potential of novel technologies.…”

Emerging Nuclear Medicine Imaging of Atherosclerotic Plaque Formation

“…This phenomenon is most pronounced in hypoxic areas where it compensates for inefficient glucose utilization [ 48 ]. The possibilities and limitations of this technique were discussed in a previous study [ 7 ].…”

“…Choline incorporation into the cell membrane is a multi-stage process, the main stages of which include entering the cell via specific transport mechanisms, phosphorylation by choline kinase, and conversion to phosphatidylcholine [ 49 ]. This technique was discussed in a previous study [ 7 ].…”

“…In our previous review, we discussed radiopharmaceuticals that are available for the clinical practice of plaques and the role of vulnerable plaque in major cardiovascular events [ 7 ]. The goal of this review is to analyze published studies of radiopharmaceuticals targeted at components of the atherosclerotic process but still described only in experimental or small-scale clinical studies.…”