The Role of Perivascular Fat in the Diagnosis and Prognosis of Atherosclerosis

Abstract

Cardiovascular diseases are the leading cause of morbidity and mortality globally, with obesity serving as a significant yet complex risk factor in this regard. Obesity represents a heterogenous set of conditions that consist of interactions between metabolic physiology, genetic-as well as environmental-factors. Recent advances in adipose tissue biology have provided greater understanding into the distinct structures and functions of different adipose tissue depots. This includes perivascular adipose tissue, which has been shown to engage in bi-directional paracrine-, vasocrine-and endocrine-signalling with the vascular wall that regulates the vascular redox state and atherogenesis. This has implications for how we approach the treatment of cardiometabolic disease, where novel insulin-sensitising agents might reduce the risk of atherosclerosis through pleiotropic effects on the vascular wall, both directly and indirectly through modulating the adipose tissue secretome. Importantly, clinical imaging modalities for visualisation of peri-vascular adipose tissue now exist that allow for more accurate cardiovascular risk-stratification and raise the possibility of more targeted therapeutic approaches in selected patients. In particular, the perivascular Fat Attenuation Index (an artificial intelligence enhanced cardiac computed tomography biomarker) has allowed for the detection of inflammatory changes in perivascular adipose tissue that holds significant potential to improve secondary risk management. Consequently, this review summarises how perivascular adipose tissue biology contributes to the development of atherosclerosis, in addition to discussing how these developments can be detected using novel cardiovascular imaging techniques.

Advances in Clinical Imaging of Vascular Inflammation

“… 51 Adiponectin can then diffuse back to the vascular wall and proximal myocardial tissue and reduce superoxide production by suppressing the activity of nicotinamide adenine dinucleotide phosphate oxidases, as well as by improving the coupling of endothelial nitric oxide synthase in the vascular endothelium. 46 , 47 , 52 During the process of shifting the phenotype of PVAT adipocytes from energy storing to active secretory cells, their dimensions, shape, and content change, becoming smaller in size and with reduced intracellular lipid content.…”