Using advanced PET/MRI technology researchers at the Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain detected arterial inflammation in regions that have yet to develop atherosclerotic plaques (Fernández-Friera L et al Vascular Inflammation in Subclinical Atherosclerosis Detected by Hybrid PET/MRI. J Am Coll Cardiol. 2019; 73(12): 1371. doi: 10.1016/j.jacc.2018.12.075.)
In the study, the research team used PET/MRI to analyze the inflammatory process in the arteries of a group of people who had already developed atherosclerotic plaques. The results show, for the first time, that inflammation is present at early stages of atherosclerosis, above all in regions that have not developed plaques. The study also shows that this arterial atherosclerosis can be an early indication of the later appearance of plaques. The researchers are currently analyzing the role of arterial inflammation in this process. Although atherosclerosis is known to be a chronic inflammatory disease, the prevalence and distribution of inflammation at early disease stages was unknown.
Dr. Valentín Fuster, CNIC Director and lead investigator on the project, emphasized the power of modern diagnostic imaging technology, which “has revealed that inflammation is present in only 10% of established plaques.” Study coauthor Dr. J Sanz explained that “the atherosclerotic plaques showing signs of inflammation are large, have a high cholesterol content, and tend to be located in the femoral arteries at the arterial bifurcations.” Nevertheless, “most inflammation identified in the arteries of this study subpopulation are located in vessel regions free of atherosclerotic plaques.”
Sanz went on to explain that the study data show inflammation in the arteries of “almost half of the participants, occurring more frequently in the femoral arteries.” Dr. Fernández-Friera added, “inflammation was associated with the presence of more risk factors; obesity and smoking in particular were independent predictors of the presence of arterial inflammation.”
Dr. Fuster emphasized that these findings demonstrate the power of PET/MRI technology to produce live images of inflammation related to systemic atherosclerosis, thus enabling the study of the disease in early stages and the identification of individuals likely to benefit from early medical intervention. He added “Future studies should investigate whether inflammation precedes the development of the plaque and assess how the quantification of inflammation might contribute to the evaluation of cardiovascular risk.”