Detecting human coronary inflammation by imaging perivascular fat

Perivascular adipocyte size is related to the lipid profile and inflammatory changes in a healthy population

Inflammatory changes in perivascular adipose tissue are associated with atherosclerotic lesions in the adjacent artery and can also be used as a marker in patient workup. While adipocyte size is known to be closely related to adipose tissue dysfunction and inflammation, it has not been widely studied in perivascular adipose tissue obtained from healthy human subjects without clinical atherosclerosis. In this cross-sectional study, we addressed this issue by measuring adipocyte size and defining its relationship to cardiovascular risk factors in a healthy cohort of living kidney donors. The presence of cardiovascular risk factors was established by a standardized questionnaire, clinical measurements and body composition analyses. Adipocyte size was measured in the perivascular depot. The proportions of various macrophage subtypes were determined by flow cytometry. To confirm the results, the proportion of CD68  +  macrophages was additionally assessed by immunohistochemistry. A correlation and principal component analyses were performed to explore associations. Adipocyte size in perivascular adipose tissue correlated with markers of lipid metabolism, inflammation, and glucose metabolism. Further, the positive correlation with the pro-inflammatory subpopulation of macrophages suggests a strong local effect of perivascular adipose tissue. Perivascular adipocyte size was associated with cardiovascular risk factors and markers of inflammation in a healthy cohort of living kidney donors. This further supports the local role of adipose tissue dysfunction and inflammation in early atherosclerosis development and detection.

Machine learning-based radiomic features of perivascular adipose tissue in coronary computed tomography angiography predicting inflammation status around atherosclerotic plaque: a retrospective cohort study

OBJECTIVES

This study expolored the relationship between perivascular adipose tissue (PVAT) radiomic features derived from coronary computed tomography angiography (CCTA) and the presence of coronary artery plaques. It aimed to determine whether PVAT radiomic could non-invasively assess vascular inflammation associated with plaque presence.

METHODS

In this retrospective cohort study, data from patients undergoing coronary artery examination between May 2021 and December 2022 were analyzed. Demographics, clinical data, plaque location and stenosis severity were recorded. PVAT radiomic features were extracted using PyRadiomics with key features selected using Least Absolute Shrinkage and Selection Operator (LASSO) and recursive feature elimination (RFE) to create a radiomics signature (RadScore).Stepwise logistic regression identified clinical predictors. Predictive models (clinical, radiomics-based and combined) were constructed to differentiate plaque-containing segments from normal ones. The final model was presented as a nomogram and evaluated using calibration curves, ROC analysis and decision curve analysis.

RESULTS

Analysis included 208 coronary segments from 102 patients. The RadScore achieved an Area Under the Curve (AUC) of 0.897 (95% CI: 0.88-0.92) in the training set and 0.717 (95% CI: 0.63-0.81) in the validation set. The combined model (RadScore + Clinic) demonstrated improved performance with an AUC of 0.783 (95% CI: 0.69-0.87) in the validation set and 0.903 (95% CI: 0.83-0.98) in an independent test set. Both RadScore and combined models significantly outperformed the clinical model (p < .001). The nomogram integrating clinical and radiomics features showed robust calibration and discrimination (c-index: 0.825 in training, 0.907 in testing).

CONCLUSION

CCTA-based PVAT radiomics effectively distinguished coronary artery segments with and without plaques. The combined model and nomogram demostrated clinical utility, offering a novel approach for early diagnosis and risk stratification in coronary heart disease.

Pericoronary adipose tissue: potential for pathological diagnosis and therapeutic applications

Excessive accumulation of epicardial adipose tissue (EAT) is known to be a risk factor for coronary artery disease and heart failure. In particular, it is thought that inflammation of pericoronary adipose tissue (PCAT) affects the pathology of various coronary artery diseases (CAD). EAT and PCAT are thought to be new therapeutic targets for preventing cardiovascular disease. Although there are no established drugs that specifically reduce inflammation of EAT or PCAT, the basic approach is to improve lifestyle-related diseases through exercise and diet, and to use metabolic improvement drugs and anti-inflammatory drugs as soft support. Potential candidates include statins, SGLT2 inhibitors, and GLP- 1 receptor agonists. In addition to conventional treatments that target substances within blood vessels, treatments that target EAT and PCAT by directly enveloping the coronary arteries and myocardium from outside the body are expected to further suppress cardiovascular events.

Serial assessment of coronary artery inflammation using cardiac CT in anthracycline chemotherapy for breast cancer

OBJECTIVES

There is limited evidence of the pericoronary fat attenuation index (FAI) as an imaging marker to assess cancer therapy-related cardiovascular toxicity. We aimed to measure FAI in four consecutive coronary CT angiography (CTA) scans before and 3, 6, and 12 months after anthracycline treatment in patients with breast cancer to determine trends in dynamic changes in FAI after treatment.

METHODS

We performed a post hoc analysis of a prospective study (between August 2019 and July 2020) in which anthracycline-induced myocardial injury was evaluated using cardiac CT. FAI was quantified using coronary CTA images before and 3, 6, and 12 months after anthracycline treatment. The FAIs of the three coronary arteries were averaged to calculate the FAI (Total).

RESULTS

FAI was analyzed on 14 patients with breast cancer who had adequate CT image quality (mean age, 62 years ± 11 (SD); 14 women). During the observation period, all 14 patients treated with anthracycline developed mild asymptomatic cardiac dysfunction related to cancer treatment (CTRCD). FAI (Total) showed a gradual increase during the observation period compared to baseline (baseline: -77.3 ± 5.6 HU, 3 months: -77.1 ± 4.8 HU, 6 months: -76.5 ± 5.4 HU, 12 months: -73.8 ± 5.8 HU). FAI (Total) was significantly elevated at 12 months compared to baseline (p < 0.001).

CONCLUSION

In patients with breast cancer, FAI showed a gradual increase at 3, 6, and 12 months after treatment with anthracyclines compared to before treatment. FAI may be used as an imaging biomarker of coronary artery inflammation in the follow-up of anthracycline therapy and may contribute to the personalization of therapy through early detection of coronary toxicity.

KEY POINTS

Question Is pericoronary fat attenuation index (FAI) a potential imaging biomarker for assessing changes in pericoronary adipose tissue related to cancer therapy-related cardiovascular toxicity? Findings In 14 patients with breast cancer, FAI showed a gradual increase at 3, 6, and 12 months after treatment with anthracyclines compared to before treatment. Clinical relevance FAI may be an imaging biomarker for the detection and treatment of cancer therapy-related cardiovascular toxicity.

Inflammation in atherosclerotic cardiovascular disease: From diagnosis to treatment

BACKGROUND

Targeting inflammation offers a unique possibility to address residual cardiovascular risk in almost two thirds of all patients with prevalent atherosclerotic cardiovascular disease (ASCVD). However, despite FDA approval and the ESC 2024 Guidelines for the Management of Chronic Coronary Syndrome recommendations to implement low-dose colchicine (0.5 mg daily) in the secondary prevention of ASCVD patients with residual inflammatory risk, its clinical adoption is still limited. In this regard, a simple screening for elevated high-sensitive C-reactive protein (hsCRP) on a routine basis might help to recognize low-grade inflammation as an important therapeutic target.

RESULTS

Within the present review, we first provide recently published epidemiologic evidence that hsCRP is at least as strong a predictor of future ASCVD events as traditional lipoproteins. Furthermore, we summarize our recent knowledge on currently available strategies to modulate an inflammatory process in ASCVD and critically discuss still open issues regarding the benefit of colchicine therapy in the acute coronary setting or for stroke prevention. In addition, we also briefly touch upon some specific issues of safety related to the long-term use of colchicine. Finally, we discuss the next diagnostic and therapeutic frontiers in targeting residual inflammatory risk, such as detection of vascular/coronary inflammation by pericoronary fat attenuation or the use of ziltivekimab, a human monoclonal antibody targeting interleukin-6.

CONCLUSION

Thus, the integration of interventions aimed at lowering the inflammatory burden in combination with aggressive lipid-modifying therapy in secondary prevention may hold the potential to further reduce the still substantial burden of ASCVD.

Impact of CT reconstruction algorithms on pericoronary and epicardial adipose tissue attenuation

OBJECTIVE

This study aims to investigate the impact of adaptive statistical iterative reconstruction-Veo (ASIR-V) and deep learning image reconstruction (DLIR) algorithms on the quantification of pericoronary adipose tissue (PCAT) and epicardial adipose tissue (EAT). Furthermore, we propose to explore the feasibility of correcting the effects through fat threshold adjustment.

METHODS

A retrospective analysis was conducted on the imaging data of 134 patients who underwent coronary CT angiography (CCTA) between December 2023 and January 2024. These data were reconstructed into seven datasets using filtered back projection (FBP), ASIR-V at three different intensities (ASIR-V 30%, ASIR-V 50%, ASIR-V 70%), and DLIR at three different intensities (DLIR-L, DLIR-M, DLIR-H). Repeated-measures ANOVA was used to compare differences in fat, PCAT and EAT attenuation values among the reconstruction algorithms, and Bland-Altman plots were used to analyze the agreement between ASIR-V or DLIR and FBP algorithms in PCAT attenuation values.

RESULTS

Compared to FBP, ASIR-V 30 %, ASIR-V 50 %, ASIR-V 70 %, DLIR-L, DLIR-M, and DLIR-H significantly increased fat attenuation values (-103.91 ± 12.99 HU, -102.53 ± 12.68 HU, -101.14 ± 12.78 HU, -101.81 ± 12.41 HU, -100.87 ± 12.25 HU, -99.08 ± 12.00 HU vs. -105.95 ± 13.01 HU, all p < 0.001). When the fat threshold was set at -190 to -30 HU, ASIR-V and DLIR algorithms significantly increased PCAT and EAT attenuation values compared to FBP algorithm (all p < 0.05), with these values increasing as the reconstruction intensity level increased. After correction with a fat threshold of -200 to -35 HU for ASIR-V 30 %, -200 to -40 HU for ASIR-V 50 % and DLIR-L, and -200 to -45 HU for ASIR-V 70 %, DLIR-M, and DLIR-H, the mean differences in PCAT attenuation values between ASIR-V or DLIR and FBP algorithms decreased (-0.03 to 1.68 HU vs. 2.35 to 8.69 HU), and no significant difference was found in PCAT attenuation values between FBP and ASIR-V 30 %, ASIR-V 50 %, ASIR-V 70 %, DLIR-L, and DLIR-M (all p > 0.05).

CONCLUSION

Compared to the FBP algorithm, ASIR-V and DLIR algorithms increase PCAT and EAT attenuation values. Adjusting the fat threshold can mitigate the impact of ASIR-V and DLIR algorithms on PCAT attenuation values.

Exerkine-mediated organ interactions: A new interpretation of exercise on cardiovascular function improvement

Cardiovascular diseases impair the structure and function of distal organs, including the liver, skeletal muscle, kidney, and adipose tissue. Exercise stimulates the interaction between the cardiovascular system and distal organs that is important for disease rehabilitation and organ health. However, the mechanisms by which exercise improves cardiovascular function through exerkine-mediated organ crosstalk remain incompletely elucidated. We used cardiovascular, exercise, exerkines, skeletal muscle, liver, kidney, and adipose tissue as keywords to search for the relevant articles, sorted out the differences between different exercise types, summarized the functions of 17 exerkines, focused on reviewing and categorizing the molecular mechanisms of interactions between the cardiovascular system and remote organs. We also look forward to future research perspectives on exercise prevention and control of chronic metabolic diseases. The aim of this review is to provide a new theoretical basis for establishing clinical rehabilitation and exercise prescriptions for cardiovascular system diseases.

Vascular effects of perivascular adipose tissue-derived chemerin in obesity-associated cardiovascular disease

Perivascular adipose tissue (PVAT) is a unique and metabolically active adipose tissue that is adjacent to most systemic blood vessels. Healthy PVAT exerts anticontractile and anti-inflammatory effects, contributing to vascular protection. However, during obesity, PVAT becomes proinflammatory and profibrotic, exacerbating vascular dysfunction. Chemerin, a multifunctional adipokine, has emerged as a key regulator of vascular tone, inflammation, and remodeling. Although liver-derived chemerin dominates the circulating chemerin pool, PVAT-derived chemerin plays a more localized and functionally important role in vascular pathophysiology because of its proximity to the vessel wall. This review highlights the role of PVAT-derived chemerin in vascular health, the mechanistic involvement of PVAT-derived chemerin in certain aspects of obesity-associated cardiovascular diseases, and the therapeutic potential of targeting PVAT-derived chemerin.

Phenotyping atherosclerotic plaque and perivascular adipose tissue: signalling pathways and clinical biomarkers in atherosclerosis

Computed tomography coronary angiography provides a non-invasive evaluation of coronary artery disease that includes phenotyping of atherosclerotic plaques and the surrounding perivascular adipose tissue (PVAT). Image analysis techniques have been developed to quantify atherosclerotic plaque burden and morphology as well as the associated PVAT attenuation, and emerging radiomic approaches can add further contextual information. PVAT attenuation might provide a novel measure of vascular health that could be indicative of the pathogenetic processes implicated in atherosclerosis such as inflammation, fibrosis or increased vascularity. Bidirectional signalling between the coronary artery and adjacent PVAT has been hypothesized to contribute to coronary artery disease progression and provide a potential novel measure of the risk of future cardiovascular events. However, despite the development of more advanced radiomic and artificial intelligence-based algorithms, studies involving large datasets suggest that the measurement of PVAT attenuation contributes only modest additional predictive discrimination to standard cardiovascular risk scores. In this Review, we explore the pathobiology of coronary atherosclerotic plaques and PVAT, describe their phenotyping with computed tomography coronary angiography, and discuss potential future applications in clinical risk prediction and patient management.

Perivascular Adipose Tissue Niches for Modulating Immune Cell Function

Perivascular adipose tissue is a unique fat depot surrounding most blood vessels with a significant role in vascular function. While adipocytes compose the vast majority of the perivascular adipose tissue by area, they only account for around 20% of the total cell number. Most of the cellular component belongs to resident immune cells, with macrophages and lymphoid cells representing ≈30% and 15% of total cells, respectively. Recently, new evidence has shown that aside from their well-known role in modulating the inflammatory tone, immune cells in perivascular adipose tissue can control adipogenesis, vessel integrity, and vascular contractility through complex cellular interactions. These interactions are spatially coordinated and influenced by the environmental state. Here, we review the mechanism by which immune cells regulate perivascular adipose tissue function with a special focus on the spatial organization of immune cells and their heterotypic interactions, supporting tissue function in health and disease.

Quantification of water and lipid composition of perivascular adipose tissue using coronary CT angiography: a simulation study

Early detection of vascular inflammation via perivascular adipose tissue (PVAT) compositional changes (e.g., increased water content) could improve cardiovascular risk stratification. However, CT-based measurements face variability due to tube voltage and patient size. This study aims to quantify perivascular adipose tissue (PVAT) composition (water, lipid, protein) using coronary CT angiography and assess impacts of tube voltage, patient size, and positional variability on measurements. A 320-slice CT simulation generated anthropomorphic thorax phantoms (small, medium, large) with fat rings mimicking different patient sizes. Ten randomized water-lipid-protein inserts were placed within the thorax phantom. Three-material decomposition was applied using medium phantoms with different tube voltages and different patient sizes at 120 kV. PVAT CT number (HU) increased with higher tube voltages and larger patient sizes. The root-mean-squared errors (RMSE) for water volumetric fraction measurements were 0.26%, 0.64%, 0.01%, and 0.15% for 80, 100, 120, and 135 kV, respectively, and 0.19%, 0.35%, and 0.61% for small, medium, and large size phantoms at 120 kV, respectively. The root-mean-squared deviations (RMSD) were 3.52%, 2.94%, 4.96%, and 6.00% for 80, 100, 120, and 135 kV, respectively, and 3.82%, 3.74%, and 6.05% for small, medium, and large size phantoms at 120 kV, respectively. Clinically relevant water fractions spanned 17-37%, with inflammation expected to alter values by approximately 5%. The findings of this study indicate that, after accounting for the effects of tube voltage and patient size, perivascular adipose tissue CT number can be quantitatively represented in terms of its water composition. This decomposition method has the potential to enable quantification of water composition and facilitate early detection of coronary artery inflammation.

Coronary spotty calcification, compared with macro calcification, is associated with a higher level of vascular inflammation and plaque vulnerability in patients with stable angina

BACKGROUND AND AIMS

Spotty calcification in the coronary arteries is considered to represent plaque vulnerability, whereas more advanced calcification is thought to be a feature of advanced stable plaque. However, data supporting this notion is limited. Inflammation plays a key role in atherogenesis, including the formation of early-stage calcification. We aimed to correlate spotty calcification assessed by optical coherence tomography (OCT) with vascular inflammation assessed by percutaneous coronary adipose tissue (PCAT) attenuation on coronary computed tomography angiography (CCTA) and OCT-derived plaque vulnerability.

METHODS

Patients with stable angina pectoris who had both CCTA and OCT prior to coronary intervention were included. Patients were classified into two groups according to the type of calcification assessed by OCT at the target lesion: spotty calcification (maximal calcification arc <90° and length <4 mm) and advanced calcification (maximal calcification arc ≥90° or length ≥4 mm) group. Non-calcified plaques, and plaques with mixed spotty and advanced calcification were excluded.

RESULTS

Among 355 patients, 77 had spotty calcifications and 72 had advanced calcification. The spotty calcification group showed a significantly higher level of PCAT attenuation of target vessel (-69.6 [-75.2 to -66.1] vs. -74.6 [-83.1 to -69.7 HU], p < 0.001) and a significantly higher prevalence of lipid-rich plaque (94.8 % vs. 72.2 %, p < 0.001) and macrophage (77.9 % vs. 59.7 %, p = 0.016), compared with the advanced calcification group.

CONCLUSIONS

Plaques with spotty calcification are associated with a higher level of perivascular inflammation and a higher prevalence of features of plaque vulnerability than those with advanced calcification.

Opportunities and challenges for the use of human samples in translational cardiovascular research: a scientific statement of the ESC Working Group on Cellular Biology of the Heart, the ESC Working Group on Cardiovascular Surgery, the ESC Council on Basic Cardiovascular Science, the ESC Scientists of Tomorrow, the European Association of Percutaneous Cardiovascular Interventions of the ESC, and the Heart Failure Association of the ESC

Animal models offer invaluable insights into disease mechanisms but cannot entirely mimic the variability and heterogeneity of human populations, nor the increasing prevalence of multi-morbidity. Consequently, employing human samples-such as whole blood or fractions, valvular and vascular tissues, myocardium, pericardium, or human-derived cells-is essential for enhancing the translational relevance of cardiovascular research. For instance, myocardial tissue slices, which preserve crucial structural and functional characteristics of the human heart, can be used in vitro to examine drug responses. Human blood serves as a rich source of biomarkers, including extracellular vesicles, various types of RNA (miRNA, lncRNA, and circRNAs), circulating inflammatory cells, and endothelial colony-forming cells, facilitating detailed studies of cardiovascular diseases. Primary cardiomyocytes and vascular cells isolated from human tissues are invaluable for mechanistic investigations in vitro. In cases where these are unavailable, human induced pluripotent stem cells serve as effective substitutes, albeit with specific limitations. However, the use of human samples presents challenges such as ethical approvals, tissue procurement and storage, variability in patient genetics and treatment regimens, and the selection of appropriate control samples. Biobanks are central to the efficient use of these scarce and valuable resources. This scientific statement discusses opportunities to implement the use of human samples for cardiovascular research within specific clinical contexts, offers a practical framework for acquiring and utilizing different human materials, and presents examples of human sample applications for specific cardiovascular diseases, providing a valuable resource for clinicians, translational and basic scientists engaged in cardiovascular research.

Effect of low-dose colchicine on pericoronary inflammation and coronary plaque composition in chronic coronary disease: a subanalysis of the LoDoCo2 trial

BACKGROUND

Low-dose colchicine (0.5 mg once daily) reduces the risk of major cardiovascular events in coronary disease, but its mechanism of action is not yet fully understood. We investigated whether low-dose colchicine is associated with changes in pericoronary inflammation and plaque composition in patients with chronic coronary disease.

METHODS

We performed a cross-sectional, nationwide, subanalysis of the Low-Dose Colchicine 2 Trial (LoDoCo2, n=5522). CT angiography studies were performed in 151 participants randomised to colchicine or placebo coronary after a median treatment duration of 28.2 months. Pericoronary adipose tissue (PCAT) attenuation measurements around proximal coronary artery segments and quantitative plaque analysis for the entire coronary tree were performed using artificial intelligence-enabled plaque analysis software.

RESULTS

Median PCAT attenuation was not significantly different between the two groups (-79.5 Hounsfield units (HU) for colchicine versus -78.7 HU for placebo, p=0.236). Participants assigned to colchicine had a higher volume (169.6 mm3 vs 113.1 mm3, p=0.041) and burden (9.6% vs 7.0%, p=0.035) of calcified plaque, and higher volume of dense calcified plaque (192.8 mm3 vs 144.3 mm3, p=0.048) compared with placebo, independent of statin therapy. Colchicine treatment was associated with a lower burden of low-attenuation plaque in participants on a low-intensity statin, but not in those on a high-intensity statin (pinteraction=0.037).

CONCLUSIONS

Pericoronary inflammation did not differ among participants who received low-dose colchicine compared with placebo. Low-dose colchicine was associated with a higher volume of calcified plaque, particularly dense calcified plaque, which is considered a feature of plaque stability.

Coronary CT angiography-derived pericoronary fat attenuation index: Post-mortem histopathological correlation in fatal plaques

OBJECTIVES

The fat attenuation index (FAI) is a biomarker that has recently gained attention for reflecting perivascular inflammation in coronary arteries. We investigated the utility of the FAI in identifying high-risk coronary plaques responsible for sudden cardiac death (SCD).

METHODS

Using multiphase post-mortem CT angiography (MPMCTA), we analyzed culprit plaques from 35 individuals who died from acute coronary syndrome, comparing these to control vessels from within-subject unaffected coronary arteries, with FAI measurement. Histopathological examination of culprit plaques assessed intraplaque inflammation, adventitial inflammation, and vasa vasorum density.

RESULTS

Perivascular FAI values were significantly higher in culprit lesions than control lesions, -62.5 ± 10.4 vs. -68.5 ± 7.2 HU, respectively (p = 0.003). However, no significant differences in FAI were found between culprit lesions with and without local histopathological inflammation (p = 0.378). Additionally, FAI values ≥ -70.1 HU were more common in culprit than control lesions, though this threshold did not reach statistical significance (p = 0.081). Other imaging biomarkers, including the napkin-ring sign (p = 0.049) and plaque enhancement (p = 0.024), were more closely associated with histopathological inflammation.

CONCLUSION

Our findings support FAI as a surrogate marker of high-risk coronary artery disease, although more extensive studies are needed to confirm its predictive accuracy for SCD. Integrating FAI with routine coronary CT angiography features could improve risk stratification in clinical settings.

SM22α-Lineage Perivascular Stromal Cells Contribute to Abdominal Aortic Aneurysm

BACKGROUND

Perivascular adipose tissue (PVAT) is a key regulator of vascular dysfunction. Impairment of PVAT phenotypic plasticity with aging may play a role in vascular pathology including abdominal aortic aneurysms (AAAs). Yet, the mechanisms underlying PVAT plasticity in aneurysm pathogenesis remain elusive.

METHODS

Single-cell RNA sequencing was performed on perivascular stromal cells from young (2- to 3-month-old) and aged (18- to 20-month-old) mice. The expression of PGC-1α (peroxisome proliferator-activated receptor gamma coactivator-1α) was measured in PVAT of aged mice and human aneurysm samples. Loss- and gain-of-function approaches were used to investigate the role of SM22α-lineage perivascular stromal cell-derived PGC-1α in aneurysm development. Molecular mechanisms were explored through transcriptome and functional studies in young and aged mice, SM22αCre; Rosa26RFP/+; PGC1αf/f and SM22αCre; Rosa26RFP/+ mice with Ang II (angiotensin II)-induced and deoxycorticosterone acetate/salt-induced AAA models.

RESULTS

SM22α+ cells accumulated in PVAT of Ang II-treated aged mice and patients with aortic aneurysms. Single-cell RNA sequencing analysis revealed that aging disrupted the differentiation potential of SM22α-lineage perivascular stromal cells and led to reduced PGC-1α levels. PGC1α downregulation in PVAT was observed in both mouse AAA models and human aneurysm lesions. In mice with SM22α-driven PGC-1α deletion, Ang II-induced AAA formation was accompanied by perivascular stromal cell-to-myofibroblast differentiation. In vitro PGC1α knockdown suppressed nuclear YAP (Yes-associated protein) signaling, reducing adipocyte differentiation, while increasing MMP2 (matrix metalloproteinase 2)-secreting myofibroblasts. Furthermore, PGC-1α overexpression in aged mice or administration of the YAP signaling inhibitor verteporfin in SM22αCre; Rosa26RFP/+; PGC1αf/f mice restored PVAT function and conferred protection against aneurysm formation. Last, we used the radiomics analysis to noninvasively evaluate PVAT in the context of AAA severity in humans.

CONCLUSIONS

PGC-1α deficiency in SM22α-lineage stromal cells disrupts the balance between adipogenic and myofibrogenic differentiation through regulating YAP signaling, ultimately promoting aneurysm development. Radiomics assessment may present a promising noninvasive approach for PVAT evaluation in aneurysms, offering valuable potential for clinical research.

Periaortic Fat Attenuation on Nongated Noncontrast Chest CT Images to Assess Changes in Arterial Inflammation: Impact of Atorvastatin

BACKGROUND

Imaging markers of atherosclerotic inflammation are needed to enhance cardiovascular risk assessment and evaluate the impact of therapies. We sought to test the hypothesis that treatments impacting arterial inflammation can be evaluated using a simplified measure of periaortic fat attenuation (FA) assessed on noncontrast, nongated computed tomography (CT) of the descending thoracic aorta.

METHODS

Measurements were performed on 18F-fluorodeoxyglucose positron emission tomography/CT images from a double-blind, randomized trial conducted between 2008 and 2009 that assessed the impact of statin therapy on arterial inflammation. Periaortic adipose tissue quantification was performed on the chest CT images over a 10 cm portion of the descending aorta. FA was determined as the mean attenuation of the entire volume of delineated periaortic fat. Arterial inflammation (aorta) and leukopoietic activity (bone marrow and spleen) were assessed by measuring standardized uptake values on 18F-fluorodeoxyglucose positron emission tomography images. Baseline relationships and changes from baseline to 12 weeks were assessed. All models evaluating FA were adjusted for baseline kilovoltage peak.

RESULTS

Sixty subjects (79.9% male, mean age 60±8.9 years) with risk factors or established atherosclerosis (32 randomized to atorvastatin 10 mg, 28 randomized to atorvastatin 80 mg) were studied. On average, it took 88±17 seconds to assess FA per subject. At baseline, FA correlated with leukopoietic activity (r=0.412; P=0.021 and r=0.442; P=0.013, for bone marrow and spleen, respectively). Furthermore, FA correlated with aortic inflammation assessed on 18F-fluorodeoxyglucose positron emission tomography as quintiles (r=0.274; P=0.043). Moreover, high dose (versus low dose) atorvastatin was associated with a significant reduction in FA after 12 weeks (standardized β=-0.603; P=0.010) after adjustment for baseline FA, kilovoltage peak, and prior statin use.

CONCLUSIONS

Periaortic FA is a marker of atherosclerotic inflammation that can be easily measured on nongated, nonenhanced chest CT images and be used to provide insights into the impact of therapies on atherosclerotic inflammation.

Peri-coronary adipose tissue attenuation and its association with plaque vulnerability and clinical outcomes in coronary artery disease using combined CCTA and OCT

Vascular inflammation plays a pivotal role in the pathogenesis of atherosclerotic plaques, driving their progression from a stable to an unstable phenotype. Previous research has identified a relationship between peri-coronary adipose tissue (PCAT) attenuation, as assessed by coronary computed tomography angiography (CCTA), and the degree of coronary inflammation, which is associated with an elevated risk of cardiovascular mortality. Nevertheless, the interplay between PCAT attenuation, as determined by CCTA, and plaque characterization via optical coherence tomography (OCT), alongside clinical outcomes, remains inadequately explored. In this study, we retrospectively analyzed data from 111 patients with coronary artery disease who underwent a sequential diagnostic workup comprising CCTA, coronary angiography (CAG), and OCT from January 2022 to May 2023. Patients were stratified into two groups based on a PCAT attenuation threshold of -70.1 Hounsfield units (HU): a high-PCAT attenuation group (n = 39) and a low-PCAT attenuation group (n = 72). The cohort was further divided into major adverse cardiac event (MACE) and non-MACE groups, depending on whether a MACE occurred during a median follow-up period of 504 days. Compared to the low-PCAT attenuation group, patients in the high-PCAT attenuation group were younger (55.77 ± 9.33 vs. 60.07 ± 9.88; p < 0.028) and exhibited a higher incidence of acute coronary syndrome (ACS) (30.8% vs. 13.9%; p = 0.033). Additionally, lipid-rich plaques (84.6% vs. 52.8%; p = 0.001), macrophages (79.5% vs. 51.4%; p = 0.004), thin-cap fibrous atherosclerotic plaques (TCFA) (43.6% vs. 25.0%; p = 0.044), and red blood clots (33.3% vs. 15.3%; p = 0.027) were more prevalent in the high-attenuation group. Multivariate logistic regression analysis revealed that high PCAT attenuation was an independent predictor of lipid plaques, macrophage presence, and TCFA. During the follow-up period, 22 patients (19.8%) experienced a primary clinical endpoint event. Patients in the MACE group demonstrated higher levels of PCAT attenuation compared to those in the non-MACE group (- 69.67 [- 74.75, - 65.59] HU vs. - 73.67 [- 76.67, - 69.50] HU, p = 0.037). Multivariate Cox proportional hazards regression modeling further substantiated that elevated PCAT attenuation was independently associated with an increased risk of MACE. In conclusion, the high-attenuation group exhibited more OCT-detected features indicative of vulnerable plaques and a higher frequency of MACE events relative to the low-attenuation group. These findings suggest a significant association between elevated vascular inflammation, as reflected by PCAT attenuation, vulnerable plaque characteristics identified by OCT, and poorer clinical outcomes.

The accumulation of epicardial adipose tissue is associated with cardiovascular death after open surgical repair for abdominal aortic aneurysms

BackgroundThe accumulation of adipose tissue, such as increased epicardial adipose tissue volume (EATV) and visceral fat area (VFA), is associated with the development of cardiovascular (CV) disease. However, little information is available regarding the relationship between EATV and CV death in patients who undergo open surgical repair (OSR) for abdominal aortic aneurysms (AAAs). The aim of this study was to evaluate the association between adipose tissue and CV death and to identify factors related to CV death after AAA repair.MethodsBetween June 2005 and December 2019, a total of 739 patients underwent OSR for AAA with or without iliac artery aneurysm and isolated iliac artery aneurysm at our institution. AAA with a diameter of 50 mm or more and iliac artery aneurysm with 35 mm or greater were considered to be a surgical indication. Patients with ruptured AAAs and infected AAAs were excluded. Four hundred ninety-two patients with preoperative optimal computed tomography (CT) scans were included in this study. The EATV, VFA, and subcutaneous fat area (SFA) were retrospectively quantified from preoperative noncontrast CT images. The EATV index was defined as the EATV divided by the body surface area, and the VFA index and SFA index were defined as each number divided by height squared. The correlations among the EATV, VFA, and SFA indices were analyzed, and the cut-off values of the parameters for predicting CV death after OSR for AAA patients were determined via receiver operating characteristic curves. Regression analysis was used to assess predictors of CV death during the follow-up period. Cox hazard regression analysis was performed.ResultsThe median age was 71 years, and 12% of the patients were female. The median body mass index was 23.1 kg/m2. The prevalence of comorbidities was 31% for coronary artery disease, 9% for stroke, 15% for diabetes, and 41% for chronic kidney disease. The median follow-up period for overall patients was 62.5 months (interquartile range: 33.7-99.6). The EATV index was positively correlated with the VFA (R = 0.615, p < .001) and SFA (R = 0.421, p < .001) indices. The cut-off value of the EATV index was 73.8 cm3/m2 (area under the curve (AUC); 0.566). Multivariate analysis revealed that age ≥75 years and an EATV index ≥73.8 cm3/m2 were significantly associated with CV death after AAA repair.ConclusionsThis study demonstrated that the EATV index was associated with CV death in patients who underwent OSR for AAA, suggesting its potential utility as a novel risk stratification tool for personalized postoperative management.

Prognostic Value of Pericoronary Fat Attenuation Index on Computed Tomography for Hospitalization for Heart Failure

BACKGROUND

Pericoronary fat attenuation index (FAI) assessed on computed tomography is associated with the inflammation of the pericoronary artery.

OBJECTIVES

This study aimed to investigate whether pericoronary FAI predicts hospitalization for heart failure with preserved ejection fraction (HFpEF).

METHODS

This retrospective single-center study included 1,196 consecutive patients who underwent clinically indicated coronary computed tomography angiography (CCTA) and transthoracic echocardiography. We assessed the FAI of proximal 40-mm segments for each major epicardial coronary vessel. The primary outcome was the incidence of hospitalization for HFpEF. Patients were divided into groups based on the optimal cutoff value for predicting hospitalization for HFpEF by receiver operating characteristic curve analysis.

RESULTS

During a median follow-up of 4.3 years, 29 hospitalizations for HFpEF occurred. Multivariable Cox regression analysis revealed that a left anterior descending artery (LAD)-FAI ≥-63.4 HU and a left circumflex artery-FAI ≥-61.6 HU were significantly associated with hospitalization for HF after adjustment for age and sex (HR: 4.8; 95% CI: 2.1-10.8 and HR: 4.5; 95% CI: 2.1-9.4, respectively). The addition of LAD-FAI >-63.4 HU to a model incorporating other risk factors, including hypertension, estimated glomerular filtration rate <60 mL/min/1.73 m2, and significant stenosis on CCTA, increased the C-statistic for predicting hospitalization for HFpEF from 0.646 to 0.750 (P = 0.010).

CONCLUSIONS

LAD- and left circumflex artery-FAI can predict hospitalization for HFpEF in patients undergoing clinically indicated CCTA. Pericoronary inflammation may be useful for identifying patients at high risk of developing HFpEF.

The pericoronary adipose tissue attenuation in CT strongly depends on kernels and iterative reconstructions

OBJECTIVES

To investigate the influence of kernels and iterative reconstructions on pericoronary adipose tissue (PCAT) attenuation in coronary CT angiography (CCTA).

MATERIALS AND METHODS

Twenty otherwise healthy subjects (16 females; median age 52 years) with atypical chest pain, low risk of coronary artery disease (CAD), and without CAD in photon-counting detector CCTA were included. Images were reconstructed with a quantitative smooth (Qr36) and three vascular kernels of increasing sharpness levels (Bv36, Bv44, Bv56). Quantum iterative reconstruction (QIR) was either switched-off (QIRoff) or was used with strength levels 2 and 4. The fat-attenuation-index (FAI) of the PCAT surrounding the right coronary artery was calculated in each dataset. Histograms of FAI measurements were created. Intra- and inter-reader agreements were determined. A CT edge phantom was used to determine the edge spread function (ESF) for the same datasets.

RESULTS

Intra- and inter-reader agreement of FAI was excellent (intra-class correlation coefficient = 0.99 and 0.98, respectively). Significant differences in FAI were observed depending on the kernel and iterative reconstruction strength level (each, p < 0.001), with considerable inter-individual variation up to 34 HU and intra-individual variation up to 33 HU, depending on kernels and iterative reconstruction levels. The ESFs showed a reduced range of edge-smoothing with increasing kernel sharpness, causing an FAI decrease. Histogram analyses revealed a narrower peak of PCAT values with increasing iterative reconstruction levels, causing a FAI increase.

CONCLUSIONS

PCAT attenuation determined with CCTA heavily depends on kernels and iterative reconstruction levels both within and across subjects. Standardization of CT reconstruction parameters is mandatory for FAI studies to enable meaningful interpretations.

KEY POINTS

Question Do kernels and iterative reconstructions influence pericoronary adipose tissue (PCAT) attenuation in coronary CT angiography (CCTA)? Findings Significant differences in fat-attenuation-index (FAI) were observed depending on the kernel and iterative reconstruction strength level with considerable inter- and intra-individual variation. Clinical relevance PCAT attenuation heavily depends on kernels and iterative reconstructions requiring CT reconstruction parameter standardization to enable meaningful interpretations of fat-attenuation differences across subjects.

Incremental Value of Pericoronary Adipose Tissue Radiomics Models in Identifying Vulnerable Plaques

OBJECTIVE

Inflammatory characteristics in pericoronary adipose tissue (PCAT) may enhance the diagnostic capability of radiomics techniques for identifying vulnerable plaques. This study aimed to evaluate the incremental value of PCAT radiomics scores in identifying vulnerable plaques defined by intravascular ultrasound imaging (IVUS).

METHODS

In this retrospective study, a PCAT radiomics model was established and validated using IVUS as the reference standard. The dataset consisted of patients with coronary artery disease who underwent both coronary computed tomography angiography and IVUS examinations at a tertiary hospital between March 2023 and January 2024. The dataset was randomly assigned to the training and validation sets in a 7:3 ratio. The diagnostic performance of various models was evaluated on both sets using the area under the curve (AUC).

RESULTS

From 88 lesions in 79 patients, we selected 9 radiomics features (5 texture features, 1 shape feature, 1 gray matrix feature, and 2 first-order features) from the training cohort (n = 61) to build the PCAT model. The PCAT radiomics model demonstrated moderate to high AUCs (0.847 and 0.819) in both the training and test cohorts. Furthermore, the AUC of the PCAT radiomics model was significantly higher than that of the fat attenuation index model (0.847 vs 0.659, P  < 0.05). The combined model had a higher AUC than the clinical model (0.925 vs 0.714, P  < 0.01).

CONCLUSIONS

The PCAT radiomics signature of coronary CT angiography enabled the detection of vulnerable plaques defined by IVUS.

High-risk plaque features and perivascular inflammation

BACKGROUND

The association between high-risk plaque (HRP) on coronary computed tomography angiography (CTA) and the level of perivascular inflammation has not been fully investigated.

METHODS

Patients who underwent both CTA and optical coherence tomography (OCT) were included. The level of perivascular inflammation was assessed by pericoronary adipose tissue (PCAT) attenuation at two levels: lesion-specific and the proximal segment of the culprit vessel. HRP features included positive remodeling (PR), low-attenuation plaque (LAP), napkin-ring sign (NRS), and spotty calcification (SC).

RESULTS

OCT features of plaque vulnerability were evaluated in culprit vessels. A total of 1360 lesions (413 culprit lesions and 947 non-culprit lesions) from 413 patients were evaluated. Lesion-specific PCAT attenuation was higher in lesions with any HRP feature except SC (present vs. absent: PR -71.3 ​± ​10.1 vs. -74.1 ​± ​11.7, P ​< ​0.001; LAP -71.7 ​± ​9.9 vs. -73.0 ​± ​11.4, P ​= ​0.025; NRS -70.3 ​± ​9.6 vs. -72.9 ​± ​11.1, P ​= ​0.001; and SC -71.9 ​± ​9.9 vs. -73.0 ​± ​11.5, P ​= ​0.082). After adjusting for confounders, only PR was associated with higher lesion-specific PCAT attenuation. The number of lesions with PR significantly correlated with higher levels of perivascular inflammation measured by culprit vessel PCAT attenuation. The number of lesions with PR was associated with higher lipid index and macrophage grade at culprit vessels.

CONCLUSIONS

Among 4 HRP features, only PR was significantly associated with higher lesion-specific PCAT attenuation. The number of plaques with PR correlated with the level of perivascular inflammation and vulnerability.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT04523194.

Role of Immune Cells in Perivascular Adipose Tissue in Vascular Injury in Hypertension

Hypertension is associated with vascular injury characterized by vascular dysfunction, remodeling, and stiffening, which contributes to end-organ damage leading to cardiovascular events and potentially death. Innate (macrophages and dendritic cells), innate-like (γδ T cells) and adaptive immune cells (T and B cells) play a role in hypertension and vascular injury. Perivascular adipose tissue that is the fourth layer of the blood vessel wall is an important homeostatic regulator of vascular tone. Increased infiltration of immune cells in perivascular adipose tissue in hypertension results in generation of oxidative stress and production of cytokines that may cause vascular injury. This review presents an overview of the role of the different immune cells that infiltrate the perivascular adipose tissue and are involved in the pathophysiology of hypertension.

Chest-CT-based radiomics feature of epicardial adipose tissue for screening coronary atherosclerosis

BACKGROUND AND AIMS

This study aims to investigate the diagnostic value of chest-CT epicardial adipose tissue (EAT) radiomics feature in coronary atherosclerotic stenosis.

METHODS

Clinical data from 215 individuals who underwent coronary angiography and chest-CT scan from January to July 2022 at our institution were retrospectively analyzed. Based on the coronary angiography results, the total population, men, and women were divided into the CAD group and non-CAD group. radiomics feature of EAT at the level of the bifurcation of the left-main coronary artery on the transverse level of chest CT were measured. The features contain both first-order feature and shape-order feature.The differences between groups were analyzed using the t test or Chi-square test. The diagnostic efficacy of each parameter in diagnosing atherosclerotic stenosis of coronary arteries was assessed by plotting the receiver operating characteristic (ROC) curve.

RESULTS

First-order features: Mean, IntDen, Median, and RawIntDen; shape-order features: Area, Perim, Round, and BSA index; and clinical index: HbA1c showed statistical significance between the CAD group and the non-CAD group. The ROC curve analysis demonstrated high diagnostic efficacy, with the best for diagnostic efficacy being Median for the first-order feature parameter (AUC, 0.753; 95% confidence interval [CI], 0.689-0.817; t = 4.785, p < 0.001), Round for the shape-order feature (AUC, 0.775; 95% CI, 0.714-0.836; t = 7.842, p < 0.001), and HbA1c for the clinical index (AUC, 0.797; 95% CI, 0.783-0.856; t = 6.406, p < 0.001). After dividing the participants into male and female subgroups, the best diagnostic efficacy was observed with the BSA index for men (AUC, 0.743; 95% CI, 0.656-0.829; t = 5.128, p < 0.001) and Round for women (AUC, 0.871; 95% CI, 0.793-0.949; t = 7.247, p < 0.001).

CONCLUSIONS

Median, Round in radiomics feature of EAT on chest CT may play a role in the assessment of coronary atherosclerotic stenosis.

Radiomic phenotype of peri-coronary adipose tissue as a potential non-invasive imaging tool for detecting atrial fibrillation

OBJECTIVES

Epicardial adipose tissue (EAT) contributes to atrial fibrillation (AF). We sought to explore the role of fat attention index (FAI), volume, and fat radiomic profile (FRP) of peri-coronary artery adipose tissue (PCAT) on coronary computed tomography angiography (CCTA) in determining the presence of AF and differentiating its types.

METHODS

This study enrolled 300 patients who underwent CCTA retrospectively and divided them into AF (n = 137) and non-AF (n = 163) groups. The imaging parameters of FAI, volume, and FRP were excavated and measured after PCAT segmentation. Every coronary artery extracted 853 radiomics and a total of 2559 radiomics were collected. Significant and relevant FRP was screened by random forest algorithm based on machine learning, and then 3 models-VF (FAI and volume), FRP, and FRPC (FRP and clinical factors)-were then compared. Among AF individuals, the FRP and FRPC scores of persistent AF (PerAF, n = 44) and paroxysmal AF (PAF, n = 93) were compared with boxplot.

RESULTS

In the test cohort, FRP score demonstrated excellent distinctive ability in identifying AF, with an area under the curve (AUC) of 0.89, compared with the model incorporating FAI and volume (AUC = 0.83). The FRPC model, which combined FRP with clinical factors, showed an improved AUC of 0.98. Among AF types, FRP and FRPC scores are significantly higher in the PerAF than PAF patients (P < .001) and 20 most contributive features were selected in identifying AF.

CONCLUSION

Textural radiomic features derived from PCAT on coronary CTA detect micro-pathophysiological information associated with AF, which may help identify and differentiate AF and provide a hopeful imaging target.

ADVANCES IN KNOWLEDGE

The analysis of epicardial tissue around coronary arteries helps identify and differentiate atrial fibrillation and its types. Fat radiomic profiles derived from peri-coronary arteries fat could provide a non-invasive tool for atrial fibrillation.

Non-invasive imaging assessment in angina with non-obstructive coronary arteries (ANOCA)

Due to its significant prevalence and clinical implications, angina with non-obstructive coronary arteries (ANOCA) has become a major focus in modern cardiology. In fact, diagnosing ANOCA presents a significant challenge. The final diagnosis is often difficult, delayed, and frequently necessitates an invasive assessment through coronary angiography. However, recent improvements in non-invasive cardiac imaging allow a diagnosis of ANOCA using a combination of clinical evaluation, anatomical coronary imaging, and functional testing. This narrative review aims to critically assess various non-invasive diagnostic methods and propose a multimodal approach to diagnose ANOCA and tailor appropriate treatments.

Pericoronary fat attenuation in stenotic and vulnerable coronary artery plaques: Implications for coronary artery disease and associated conditions

Background

Pericoronary adipose tissue density (PCAT) is a parameter that quantifies inflammation and atherosclerosis around the coronary arteries.

Purpose

To investigate the correlation between PCAT and plaque features, stenosis degrees in coronary arteries (LAD, RCA, Cx) with stenotic vulnerable plaques.

Material and methods

A Retrospective study including 103 patients (64M, 39F) who underwent coronary computed tomography was retrospectively examined at a single center. PCAT and high-risk plaques were measured independently and compared to stenosis and coronary artery type. Adipose tissue attenuation, ranging from -180 to -25 HU, was measured along the plaque's length and in a 0.5-1 mm region around the perilesional coronary arteries.

Results

The PCAT values increases with the degree of stenosis in the LAD, Cx, and RCA (r = 0.9161, p < .001; r = 0.9717, p < .001; r = 0.9315, p < .001, respectively). PCAT values demonstrate a positive pattern when plaque length increases in all coronary arteries (r = -0.6316, p < .001; r = -0.8825, p < .001; r = -0.7529, p < .001; LAD, Cx, RCA). PCAT values differed significantly based on plaque type in all coronary arteries. Calcified plaques showed statistically significant differences compared to both soft and mixed plaques (p < .05). Patients with positive remodeling had PCAT values of -69.43 (±8.76) HU, while cases without positive remodeling had PCAT values of -84.54 (±7.65) HU, indicating a significant difference (p < .05).

Conclusion

The combined evaluation of plaque features, stenosis degree, and PCAT provides a more accurate prediction of possible acute coronary syndrome cases than analyzing stenosis degree alone.

Different plaque types and its association with the volume and attenuation of pericoronary adipose tissue as assessed by coronary computed tomography angiography

AIM

To explore the relationship between different plaque types and pericoronary adipose tissue (PCAT) volume and attenuation values in patients with stable coronary artery disease (CAD) based on coronary computed tomographic angiography (CCTA).

MATERIALS AND METHODS

Three hundred twenty one patients with stable CAD who underwent CCTA from May 2022 to March 2023 were enrolled. Using semi-automatic software, PCAT volumes and CT attenuation values were measured around the plaque and in the segment and proximal coronary artery where the plaque was located. To compare whether there was a statistical difference in PCAT volume and attenuation values among different plaque types in the periplaque, the segment, and proximal coronary artery in which the plaque was positioned.

RESULTS

In total, 552 lesions were included, with 299 calcified plaques (CPs), 174 noncalcified plaques (NCPs), and 79 mixed plaques (MPs). There were excellent agreements between the two radiologists regarding the measured PCAT volumes and attenuation values (all interclass correlation coefficients values > 0.80). The periplaque PCAT volume was larger in CPs and MPs than in NCPs (291.98[213.25,381.03] mm3 vs. 261.00[173.25,377.85] mm3 vs. 206.54[139.72,284.07] mm3, P < 0.05), and the PCAT attenuation values around the plaque and the segment in which the plaque was positioned were higher in NCPs and MPs compared with CPs (-73.00[-79.00,-68.00] HU vs. -76.00[-79.00,-71.00] HU vs. -85.00[-92.00,-80.00] HU, -81.72 ± 0.70 HU vs. -80.73 ± 1.03 HU vs. -84.31 ± 0.49 HU; P < 0.05).

CONCLUSION

PCAT volume and attenuation values differed significantly among different plaque types, and the differences are particularly significant in measurements around the plaque.

Effect of statin therapy on coronary inflammation assessed by pericoronary adipose tissue computed tomography attenuation

AIMS

Pericoronary adipose tissue (PCAT) attenuation on coronary computed tomography angiography (CCTA) is an imaging biomarker of coronary inflammation. The natural history of PCAT attenuation remains unknown. High-intensity statin therapy has pleiotropic anti-inflammatory effects. We sought to assess temporal changes in PCAT attenuation in patients with and without statin therapy.

METHODS AND RESULTS

This was a multicentre observational study that included consecutive patients with stable coronary artery disease (CAD) undergoing clinically indicated serial CCTA with identical scan parameters ≥ 12 months apart between May 2013 and July 2022. Using semi-automated software, PCAT attenuation was measured on a per-lesion level (PCATlesion) and per-patient level around the proximal right coronary artery (PCATRCA). Of the 96 patients (57 ± 11 years, 60% male), 34 patients were not on a statin at baseline or follow-up (statin-naive), 26 patients were commenced on a statin after the baseline scan (statin-commenced), and 34 patients were on a statin at both time points (statin-continued). There was no significant difference between the groups for age, sex, body mass index (BMI), and prevalence of traditional cardiovascular risk factors except for dyslipidaemia (25.0% vs. 34.6% vs. 64.7%, P < 0.01 for trend). At a median follow-up of 3.8 years, there was a significant reduction in PCATlesion in the statin-commenced (-79.4 ± 11.7 to -86.5 ± 10 HU, P < 0.001) and the statin-continued (-83.5 ± 8.5 to -90.6 ± 8.5 HU, P = 0.001) groups. Meanwhile, no significant difference in PCATlesion was observed in the statin-naïve group (-84.4 ± 9.7 to -86.6 ± 9.5, P = 0.1). Multivariate analysis showed statin intensity and LDL change to be independently associated with percentage change of PCATlesion, after correcting for cardiovascular risk factors, changes in body weight, and coronary artery calcium score.

CONCLUSION

Statin therapy was associated with a reduction in PCATlesion, while no significant change in PCATlesion was observed without statin therapy. If validated in larger studies, PCAT attenuation could potentially be used to monitor the response of the coronary arteries to statins and guide treatment.

Sex-Specific Characteristics of Perivascular Fat in Aortic Aneurysms

Aortic aneurysms (AAs), the dilation or widening of the aorta, lead to dissection or rupture with high morbidity and mortality if untreated. AA displays gender disparities in its prevalence, progression and outcomes, with women having worse outcomes and faster aneurysm growth. However, current guidelines do not address gender dimorphism, emphasizing the urgent need for personalized treatment strategies and further research. Perivascular adipose tissue (PVAT), a unique type of fat surrounding blood vessels, plays a critical role in maintaining vasomotor tone and vascular homeostasis, with dysfunction associated with chronic inflammation and vessel-wall remodeling. Indeed, PVAT dysfunction promotes the development of aortic aneurysms, with hormonal and biomechanical factors exacerbating the pathological vascular microenvironment. The sexually dimorphic characteristics of PVAT include morphological, immunological, and hormonally mediated differences. Thus, targeting PVAT-mediated mechanisms may be a promising option for the (gender-specific) therapeutic management of cardiovascular pathologies. This review examines the emerging importance of PVAT in vascular health, its potential therapeutic implications for AA, and identifies gaps in the current state of research.

Improved ASCVD Screening in Diabetes: a Focus on Scoring Models and Detection Techniques

Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of morbidity and mortality in individuals with type 2 diabetes mellitus (T2DM). Diabetes accelerates the progression of atherosclerosis through key mechanisms such as insulin resistance, hyperglycemia, dyslipidemia, chronic inflammation, and oxidative stress, significantly increasing the risk of coronary artery disease, stroke, and heart failure. Traditional risk assessment models and treatment strategies often fall short in fully addressing these complexities, leaving a substantial residual cardiovascular risk in diabetic patients. This review focuses on the need for enhanced screening protocols in diabetic populations, examining advanced risk scoring models and detection techniques aimed at improving early identification and management of ASCVD. Also, this study examines the pathophysiological links between diabetes and atherosclerosis, emphasizing the need for enhanced screening protocols. Emerging tools, such as non-invasive imaging techniques (e.g., coronary artery calcium scoring, CCTA) and biomarkers (e.g., polygenic risk scores), offer promise for improved early detection and risk stratification. Additionally, newer therapeutic strategies targeting inflammation and insulin resistance are being explored to mitigate cardiovascular risks in this population. Given the significant cardiovascular risk associated with diabetes, particularly T2DM, these advancements are crucial in reducing morbidity and mortality related to atherosclerotic events.

Exploring the effect of dapagliflozin on coronary inflammation in type 2 diabetes patients based on the coronary artery perivascular fat attenuation index

BACKGROUND

The pericoronary fat attenuation index (FAI) is a novel biomarker that serves as an indicator of coronary artery inflammation. Dapagliflozin has become an important component of standard treatment for type 2 diabetes because of its cardioprotective and renoprotective effects. The objective of this research was to explore how dapagliflozin impacts coronary artery inflammation in T2DM patients and to establish a novel theoretical framework for the protective role of dapagliflozin in the cardiovascular system.

METHODS

This research retrospectively included 271 T2DM patients treated with coronary computed tomography angiography (CCTA) at Hebei Provincial People's Hospital from January 2021 to November 2024, with 103 patients receiving dapagliflozin therapy (dapagliflozin+) and 168 patients not receiving dapagliflozin (dapagliflozin-) (oral dapagliflozin 10 mg/day for no less than 6 months). Baseline clinical information, laboratory markers, and CCTA-related metrics were collected and analysed across both groups. The relationship between dapagliflozin treatment and the pericoronary FAI was analysed using multiple linear regression to control for confounding variables, and the correlation between the two variables was further examined across various subgroups.

RESULTS

Compared with those in the dapagliflozin- group, the patients in the dapagliflozin+ group were younger (P<0.001), and the proportion of men was higher (P<0.05). There were no between-group differences in the baseline data, such as diabetes course, BMI, and blood lipid status (P>0.05). The FAI of the LAD and RCA in the dapagliflozin+ group was lower than that in the other groups, and the average FAI of the three coronary arteries was also significantly lower, while there was no significant difference in the LCX (LAD: dapagliflozin- group: -85.50 (-90.43, -78.27)，dapagliflozin+ group：-86.94 (-92.81, -81.57)，P= 0.044；RCA：dapagliflozin- group：-86.31 (-92.12, -80.09), dapagliflozin+ group：-88.79 (-94.59, -83.31), P= 0.019; Mean: dapagliflozin- group: -84.05 (-87.73, -77.45), dapagliflozin+ group: -84.88 (-89.82, -79.67), P= 0.022; LCX: dapagliflozin- group：-77.81 (-82.57, -71.75), dapagliflozin+ group: -78.25 (-84.56, -72.15), P = 0.260). Multiple linear regression analyses revealed an independent association between dapagliflozin treatment and a decreased in FAI in the LAD and RCA (LAD: β=-2.449; RCA: β=-3.897; P values are all less than 0.05). This association was different across various subsets of T2DM patients.

CONCLUSION

Dapagliflozin treatment is associated with a significant reduction in coronary artery inflammation in T2DM patients, which may partly explain its beneficial effects on reducing cardiovascular risk.

Association between neutrophil-lymphocyte ratio levels and mortality related to cardiovascular cause and all causes in coronary artery disease patients with low-density lipoprotein cholesterol below 1.4 mmol/L: A multicenter cohort study

BACKGROUND AND AIMS

Neutrophil-lymphocyte ratio (NLR) can reflect the residual risk of patients with coronary atherosclerotic disease (CAD). However, in CAD patients with low density lipoprotein cholesterol (LDL-C) less than 1.4 mmol/L, the relationship between NLR and poor prognosis remains unclear. The purpose of this research is to examine the relationship between NLR and mortality from cardiovascular causes as well as all causes in the study group.

METHODS AND RESULTS

From the beginning of 2007 to the end of 2020, 2749 individuals with LDL-C under 1.4 mmol/L at baseline and CAD diagnosed via coronary angiography were part of this research. The selected population was divided into four groups according to the level of NLR, and Cox regression model was used mainly to evaluate the association between NLR and cardiovascular and all-cause mortality. After a follow-up of median 6 years, a total of 182 cardiovascular deaths and 460 all-cause deaths had occurred. The Cox regression analysis of fully adjusted model showed that an elevated NLR is connected to a higher risk of mortality from cardiovascular cause (HR: 2.18, 95 %CI: 1.38-3.43) and all causes (HR: 1.33, 95 %CI: 1.02-1.74) in the fourth quartile group. Subgroup analysis indicated that younger and middle-aged patients, as well as those with multivessel coronary artery disease, may have a heightened residual risk of inflammation.

CONCLUSION

NLR can be a useful risk factor indicator for cardiovascular and all-cause mortality in CAD patients with LDL-C levels below 1.4 mmol/L, and it also points to residual risk.

Predictive value of pericoronary fat attenuation index for graft occlusion after coronary artery bypass grafting

PURPOSE

Based on coronary computed tomography angiography (CCTA), this study aimed to evaluate the predictive value of pericoronary fat attenuation index (FAI) for graft occlusion in patients following coronary artery bypass grafting (CABG).

MATERIALS AND METHODS

The clinical and imaging data of 100 patients with coronary artery disease (CAD) who underwent CCTA and subsequently received successful CABG between December 2012 and March 2024 were retrospectively collected. According to the subsequent CCTA evaluation of grafts, they were categorized into occlusion group (n = 27) and patency group (n = 73). Based on CCTA images, FAI of the proximal segment of the three coronary arteries and epicardial adipose tissue (EAT) parameters were measured and compared between the two groups. The Cox regression model was employed to screen the independent predictors of graft occlusion. The predictive model was constructed, and the receiver operating characteristic (ROC) curve was drawn to evaluate the diagnostic performance of the model.

RESULTS

Among the 100 cases, 74 were males, with a mean age was 62.42 ± 7.57 years. During the 15.50 (5.00, 36.75) months follow-up period, grafting vessel occlusion occurred in 27 patients (27.0%). The right coronary artery (RCA) in occlusion group was -73.36 ± 7.24HU, which was notably higher compared to patency group (-79.93 ± 9.75HU) (P < 0.05). Multivariable Cox regression analysis indicated that RCA FAI (HR = 5.205, 95% CI 1.938-13.979; P = 0.001) was independently correlated with graft occlusion, with an optimal cutoff value of -79.39 HU.RCA FAI added incremental prognostic value beyond clinical characteristics for patients following CABG (AUC 0.784 vs. 0.677, P = 0.027).

CONCLUSIONS

The RCA FAI can serve as a crucial predictor for graft occlusion in patients following CABG, enabling early identification of high-risk individuals and facilitating timely and effective intervention measures to enhance patient prognosis.

The interaction of lipomatous hypertrophy of the interatrial septum with pericardial adipose tissue biomarkers by computed tomography

OBJECTIVE

Novel pericardial adipose tissue imaging biomarkers are currently under investigation for cardiovascular risk stratification. However, a specific compartment of the epicardial adipose tissue (EAT), lipomatous hypertrophy of the interatrial septum (LHIS), is included in the pericardial fat volume (PCFV) quantification software. Our aim was to evaluate LHIS by computed tomography angiography (CTA), to elaborate differences to other pericardial adipose tissue components (EAT) and paracardial adipose tissue (PAT), and to compare CT with [18F]FDG-PET.

MATERIALS AND METHODS

Of 6983 patients screened who underwent coronary CTA for clinical indications, 190 patients with LHIS were finally included (age 62.8 years ± 9.6, 31.6% females, BMI 28.5 kg/cm2 ± 4.7) in our retrospective cohort study. CT images were quantified for LHIS, EAT, and PAT density (HU), and total PCFV, with and without LHIS, was calculated. CT was compared with [18F]FDG-PET if available.

RESULTS

CT-density of LHIS was higher (- 22.4 HU ± 22.8) than all other pericardial adipose tissue components: EAT right and left (97.4 HU ± 13 and - 95.1 HU ± 13) PAT right and left (- 107.5 HU ± 13.4 and - 106.3 HU ± 14.5) and PCFV density -83.3 HU ± 5.6 (p < 0.001). There was a mild association between LHIS and PAT right (Beta 0.338, p = 0.006, 95% CI: 0.098-577) and PAT left (Beta 0.249, p = 0.030; 95% CI: 0.024-0.474) but not EAT right (p = 0.325) and left (p = 0.351), and not with total PCFV density (p = 0.164). The segmented LHIS volume comprised 3.01% of the total PCFV, and 4.3% (range, 2.16-11.7%) in those with LHIS > 9 mm. [18F]FDG-PET: LHIS was tracer uptake positive in 83.3% (37.5%: mild and 45.8%: minimal) of 24 patients.

CONCLUSIONS

LHIS is a distinct compartment of PCFV with higher density suggesting brown fat and has no consistent association with EAT, but rather with PAT.

CLINICAL RELEVANCE STATEMENT

LHIS should be recognized as a distinct compartment of the EAT, when using EAT for cardiovascular risk stratification.

KEY POINTS

LHIS is currently included in EAT quantification software. LHIS density is relatively high, it is not associated with EAT, and has a high [18F]FDG-PET positive rate suggesting brown fat. LHIS is a distinct compartment of the EAT, and it may act differently as an imaging biomarker for cardiovascular risk stratification.

Incremental Prognostic Value of Perivascular Fat Attenuation Index in Patients with Diabetes with Coronary Artery Disease

Purpose To investigate whether pericoronary adipose tissue attenuation (PCATa) provides incremental prognostic value over commonly used coronary CT angiography (CCTA) parameters for predicting major adverse cardiovascular and cerebrovascular events (MACCE) in individuals with diabetes mellitus (DM). Materials and Methods This prospective study included consecutive patients with type 2 DM who underwent CCTA due to suspected coronary artery disease between January 2015 and December 2017. PCATa of three coronary arteries was measured and evaluated. Cox proportional hazards regression was performed to investigate the prognostic value of PCATa for predicting MACCE. The incremental prognostic value of PCATa for MACCE was evaluated by comparing area under the receiver operating characteristic curve (AUC) values of four models (model 1: clinical characteristics, model 2: model 1 + conventional CCTA findings [coronary artery calcium score, Leiden score], model 3: model 2 + advanced CCTA findings [high-risk plaque, CT fractional flow reserve], model 4: model 3 + PCATa). Results Of the 1029 participants (mean age, 60.2 years ± 9.9 [SD]; 539 male) included in the study, 152 (14.8%) experienced MACCE during a median follow-up of 56.5 months. PCATa independently predicted MACCE after adjustment for clinical characteristics and commonly used CCTA findings (hazard ratio, 1.86 [95% CI: 1.24, 2.80]; P = .003). The model incorporating PCATa improved predictive performance for MACCE compared with the model including clinical characteristics and conventional and advanced CCTA parameters (AUC, 0.75 [95% CI: 0.71, 0.79] vs 0.73 [95% CI: 0.68, 0.77]; P = .009). Conclusion PCATa provided incremental prognostic value beyond clinical characteristics and other CCTA findings for prediction of MACCE in individuals with DM. Keywords: CT Angiography, Cardiac, Coronary Arteries, Inflammation, Outcomes Analysis, Coronary Computed Tomography Angiography, Diabetes Mellitus, Coronary Inflammation, Pericoronary Adipose Tissue Attenuation Supplemental material is available for this article. © RSNA, 2025.

Pericoronary adipose tissue attenuation predicts compositional plaque changes: a 12-month longitudinal study in individuals with type 2 diabetes without symptoms or known coronary artery disease

BACKGROUND

Pericoronary adipose tissue attenuation (PCATa), derived from coronary computed tomography angiography (CCTA), is a novel marker of inflammation in the coronary arteries. Patients with type 2 diabetes mellitus (T2DM) are at elevated risk of coronary artery disease (CAD), potentially due to systemic inflammation. This study evaluated whether baseline PCATa predicts changes in plaque composition and burden over 12 months.

METHODS

This prospective longitudinal study included 200 participants with T2DM, who had neither symptoms nor a prior diagnosis of CAD (mean age 61 ± 9.4 years, 72% male). PCATa was measured at the baseline scan along the proximal 40 mm of each major coronary artery, and the values were averaged to calculate the participant-level PCATa. High PCATa levels were determined using the validated cut-off of -70.1 Hounsfield units. Compositional plaque changes were quantified as the differences between baseline and 12-month scans, and plaque burden was calculated as the normalized atheroma volume. Multivariable regression analyses assessed the associations between baseline PCATa and compositional plaque changes and evaluated risk factors, including high PCATa, in predicting non-calcified plaque burden progression.

RESULTS

Plaque compositional volumes and burden increased over 12 months, while PCATa remained stable. After multivariable adjustments, baseline PCATa was significantly associated with changes in total plaque volume (β = 0.005, p = 0.005), non-calcified plaque volume (β = 0.006, p = 0.007), total plaque burden (β = 1.7, p = 0.007), and non-calcified plaque burden (β = 2.0, p = 0.006), but not with calcified plaque volume or burden. High baseline PCATa was observed in 44 participants (22%) and was the only independent predictor of non-calcified plaque burden progression (odds ratio 3.5, p = 0.002).

CONCLUSIONS

Baseline PCATa is significantly associated with increases in total and non-calcified plaque volumes and burden over 12 months in participants with T2DM without symptoms or known CAD. High PCATa levels uniquely predict non-calcified plaque burden progression, suggesting that PCATa may serve as a marker for subclinical atherosclerosis progression. This warrants further investigation into PCATa for cardiovascular risk assessment, particularly in high-risk populations such as individuals with T2DM.

TRIAL REGISTRATION

Trial registration: NCT06644651.

RESEARCH INSIGHTS

What is currently known about this topic? 1. Type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD) share inflammatory mechanisms. 2. Individuals with T2DM face a two- to four-fold increased risk of CAD compared with those without T2DM. 3. Pericoronary adipose tissue attenuation (PCATa) is a novel marker of coronary inflammation. What is the key research question? Can baseline PCATa predict compositional plaque changes over 12 months in T2DM without known CAD? What is new? 1. Baseline PCATa relates to higher total and non-calcified plaque (NCP) volumes after adjustment. 2. Baseline PCATa associates with increased total- and NCP burden after multivariable adjustment. 3. High baseline PCATa (> -70.1 HU) independently predicts NCP burden progression. How might this study influence clinical practice? PCATa may be a marker for subclinical atherosclerosis progression.

Characterizing cardiac adipose tissue in post-acute myocardial infarction patients via CT imaging: a comparative cross-sectional study

AIMS

To identify differences in CT-derived perivascular adipose tissue (PVAT) and epicardial adipose tissue (EAT) characteristics that may indicate inflammatory status differences between post-treatment acute myocardial infarction (AMI) and stable coronary artery disease (CAD) patients.

METHODS AND RESULTS

A cohort of 205 post-AMI patients (age 59.8 ± 9.2, 92.2% male) was propensity-matched with 205 stable CAD patients (age 60.5 ± 10.0, 90.2% male). Coronary CT angiography and non-contrast CT scans were performed to assess PVAT mean attenuation across major coronary segments and EAT mean attenuation and volumes, respectively. For post-AMI patients, CT scans were conducted 28.6 ± 13.8 days after the AMI incidence. Post-AMI patients showed higher non-culprit PVAT and EAT mean attenuation than stable CAD patients (8.01 HU, 95% CI 5.90-10.11 HU, P < 0.001, 2.48 HU, 95% CI 0.83-4.13 HU, P = 0.003, respectively). The EAT volume percentage at higher attenuation levels was higher in post-AMI patients compared with stable CAD (33.93 cm3, 95% CI 16.86-51.00 cm3, P < 0.001), with the difference maximized at the -70 HU threshold (4.75%, 95% CI 3.64%-5.87%, P < 0.001). PVAT mean attenuation positively correlated with EAT mean attenuations and the percentage of EAT volume > -70 HU (P < 0.001 for both).

CONCLUSION

Post-AMI patients showed higher PVAT and EAT attenuation than stable CAD patients, potentially indicating AMI-associated inflammatory cardiac adipose tissue changes. A total of -70 HU can act as a potential cut-off for inflamed EAT. These findings highlight the potential of using CT-derived adipose tissue characteristics to assess inflammation and guide post-AMI management strategies.

Comparative Analysis of Perivascular Adipose Tissue Attenuation on Chest Computed Tomography Angiography in Patients with Marfan Syndrome: A Case-Control Study

Background: Marfan syndrome (MFS) is a rare autosomal dominant disorder affecting connective tissues due to mutations in the fibrillin-1 gene. These genetic changes often result in severe cardiovascular conditions, including asymptomatic thoracic aortic dilation potentially leading to dissection or rupture. Perivascular adipose tissue attenuation (PVAT) observed on computed tomography may serve as a marker of localized inflammation and indicate early histopathological changes in the vascular walls of MFS patients compared to healthy individuals. Objective: This study aimed to compare PVAT values between patients with MFS and healthy controls in order to explore whether MFS patients show higher PVAT secondary to these histopathological abnormalities. Methods: This case-control study assessed PVAT on ascending aorta through computed tomography angiography (CTA) in 54 genetically confirmed MFS patients and 43 controls with low ischemic risk, excluding those with known aortic aneurysms. Results: PVAT analysis revealed significant differences between the MFS patients and healthy controls (-70.6 HU [-72.6 HU to -68.5 HU] versus -75.1 HU [-77.1 HU to -73.1 HU], p = 0.002), suggesting potential early vascular changes in the MFS group. Conclusions: The findings underscore the potential diagnostic role of PVAT in patients with genetically confirmed MFS but normal ascending aorta diameter.

Coronary Inflammation and Cardiovascular Events in Patients Without Obstructive Coronary Artery Disease

PURPOSE OF REVIEW

This review evaluates the role of vascular inflammation in patients who develop myocardial infarction with non-obstructive coronary arteries (MINOCA). It also introduces pericoronary adipose tissue (PCAT) and epicardial adipose tissue (EAT) as possible biomarkers for risk prediction in patients with non-obstructive coronary artery disease (CAD).

RECENT FINDINGS

PCAT and EAT contribute to the development and progression of coronary artery inflammation and plaque vulnerability. Coronary computed tomography angiography (CCTA) can detect localized areas of inflammation through changes in the attenuation values of PCAT and EAT. Attenuation values can be further integrated with traditional risk factors using artificial intelligence to generate risk scores that significantly enhance prognostic accuracy in patients with and without obstructive coronary artery disease. Assessing PCAT and EAT inflammation via CCTA and AI-driven risk algorithms enable precise risk prediction of MINOCA and major adverse coronary events (MACE) in patients with non-obstructive CAD.

Assessing the impact of COmorbidities and Sociodemographic factors on Multiorgan Injury following COVID-19: rationale and protocol design of COSMIC, a UK multicentre observational study of COVID-negative controls

INTRODUCTION

SARS-CoV-2 disease (COVID-19) has had an enormous health and economic impact globally. Although primarily a respiratory illness, multi-organ involvement is common in COVID-19, with evidence of vascular-mediated damage in the heart, liver, kidneys and brain in a substantial proportion of patients following moderate-to-severe infection. The pathophysiology and long-term clinical implications of multi-organ injury remain to be fully elucidated. Age, gender, ethnicity, frailty and deprivation are key determinants of infection severity, and both morbidity and mortality appear higher in patients with underlying comorbidities such as ischaemic heart disease, hypertension and diabetes. Our aim is to gain mechanistic insights into the pathophysiology of multiorgan dysfunction in people with COVID-19 and maximise the impact of national COVID-19 studies with a comparison group of COVID-negative controls.

METHODS AND ANALYSIS

COmorbidities and Sociodemographic factors on Multiorgan Injury following COVID-19 (COSMIC) is a prospective, multicentre UK study which will recruit 200 subjects without clinical evidence of prior COVID-19 and perform extensive phenotyping with multiorgan imaging, biobank serum storage, functional assessment and patient reported outcome measures, providing a robust control population to facilitate current work and serve as an invaluable bioresource for future observational studies.

ETHICS AND DISSEMINATION

Approved by the National Research Ethics Service Committee East Midlands (REC reference 19/EM/0295). Results will be disseminated via peer-reviewed journals and scientific meetings.

TRIAL REGISTRATION NUMBER

COSMIC is registered as an extension of C-MORE (Capturing Multi-ORgan Effects of COVID-19) on ClinicalTrials.gov (NCT04510025).

Estimating inflammatory risk in atherosclerotic cardiovascular disease: plaque over plasma?

Inflammation is an important driver of disease in the context of atherosclerosis, and several landmark trials have shown that targeting inflammatory pathways can reduce cardiovascular event rates. However, the high cost and potentially serious adverse effects of anti-inflammatory therapies necessitate more precise patient selection. Traditional biomarkers of inflammation, such as high-sensitivity C-reactive protein, show an association with cardiovascular risk on a population level but do not have specificity for local plaque inflammation. Nowadays, advancements in non-invasive imaging of the vasculature enable direct assessment of vascular inflammation. Positron emission tomography (PET) tracers such as 18F-fluorodeoxyglucose enable detection of metabolic activity of inflammatory cells but are limited by low specificity and myocardial spillover effects. 18F-sodium fluoride is a tracer that identifies active micro-calcification in plaques, indicating vulnerable plaques. Gallium-68 DOTATATE targets pro-inflammatory macrophages by binding to somatostatin receptors, which enhances specificity for plaque inflammation. Coronary computed tomography angiography (CCTA) provides high-resolution images of coronary arteries, identifying high-risk plaque features. Measuring pericoronary adipose tissue attenuation on CCTA represents a novel marker of vascular inflammation. This review examines both established and emerging methods for assessing atherosclerosis-related inflammation, emphasizing the role of advanced imaging in refining risk stratification and guiding personalized therapies. Integrating these imaging modalities with measurements of systemic and molecular biomarkers could shift atherosclerotic cardiovascular disease management towards a more personalized approach.

Perivascular fat attenuation index (FAI) on computed tomography coronary angiography reclassifies individual cardiovascular risk estimation

Background

The perivascular fat attenuation index (FAI) detects and quantifies coronary inflammation by measuring phenotypic changes in perivascular adipose tissue by using computed tomography coronary angiography images.

Aim

The primary objective of this study was to evaluate the reclassification of cardiovascular (CV) risk after incorporating perivascular FAI assessment in currently used risk score algorithms.

Methods

This was a single-center, retrospective study of 200 patients with suspected coronary artery disease who underwent computed tomography coronary angiography in clinical practice between January 2022 and May 2022. From the patients who met the inclusion criteria, we included 50 patients with the highest CV risk according to the U-prevent calculator score to perform the perivascular FAI analysis. High perivascular FAI was defined as either a FAI-Score of ≥75th percentile in the left anterior descending artery or right coronary artery, or ≥95th percentile in the left circumflex artery.

Results

In 62 % of the patients, there was a reclassification in CV risk after perivascular FAI assessment; individual risk was upgraded in 22 % of patients and in 40 % their risk was downgraded. The presence of any plaque (72.7 % vs. 94.1 %; P = 0.032) and the proportion of patients with moderate-to-high coronary artery calcium score (≥100 Agatston units) was higher in the high perivascular FAI group compared to the low FAI group (76.5 % vs. 36.4 %; P = 0.016). Major adverse cardiac and cerebrovascular events did not differ between both groups.

Conclusion

The findings in this study suggest the potential valuable role of perivascular FAI assessment in individual CV risk prediction for patients with documented or suspected coronary artery disease.

Comparative Efficacy of Non-contrast vs. Contrast-enhanced CT Radiomics in Predicting Coronary Artery Plaques Among Patients with Low Agatston Scores

RATIONALE AND OBJECTIVES

Patients with a low Agatston score often present with clinical signs and symptoms suggestive of coronary artery disease, despite having minimal calcium deposits. This study aimed to compare the efficacy of low-dose non-contrast cardiac CT with coronary computed tomography angiography (CCTA) in pericoronary adipose tissue (PCAT) radiomics for predicting coronary artery plaques, using CCTA as the reference standard.

MATERIALS AND METHODS

This retrospective study analyzed 459 patients with suspected coronary artery disease and a coronary artery calcium score < 100 Agatston units, who were treated between June 2021 and December 2023 at a tertiary hospital. Three predictive models for coronary artery plaques were developed: (1) a clinical factor model, (2) a hybrid model integrating clinical factors and CT PCAT radiomics, and (3) a hybrid model integrating clinical factors and CCTA PCAT radiomics. Multivariable logistic regression and receiver operating characteristic curve evaluations were performed to develop and validate predictive models.

RESULTS

Both hybrid models showed significant correlations in the training set (r = 0.890, P < 0.001) and the validation set (r = 0.920, P < 0.001). The mean agreement in the training set is 0, with 3.42% (11/322) of the data points outside the 95% CI (-0.18-0.18, P < 0.001). The mean agreement in the validation set is -0.244, with 6.57% (9/137) of the data points outside the 95% CI (-0.443-0.045, P < 0.001).

CONCLUSIONS

Non-contract CT PCAT radiomics showed comparable efficacy to CCTA PCAT radiomics in predicting coronary artery plaques among patients with low Agatston scores.

Incremental prognostic value of pericoronary adipose tissue attenuation beyond conventional features in patients with nonobstructive coronary artery disease

BACKGROUND AND AIMS

It remains uncertain whether pericoronary adipose tissue attenuation (PCATa) is associated with clinical outcome in patients with nonobstructive coronary artery disease (CAD). We aim to investigate the incremental prognostic value of PCATa beyond clinical and coronary computed tomographic angiography (CCTA) features in patients with nonobstructive CAD.

METHODS

Consecutive patients with chest pain suspected of CAD referred for CCTA from January 2017 to December 2018 were prospectively included. Multivariable Cox proportional hazard regression analysis was employed to identify the predictive factors for major adverse cardiovascular events (MACE), while the receiver operating characteristics (ROC) curve was utilized to assess the discriminatory capacity of PCATa. Kaplan-Meier curves were ultilized to visually represent event-free survival and were compared using Log-rank tests among groups stratified by high-risk plaque (HRP) and PCATa.

RESULTS

Of the 1614 patients (mean age 59.0 years, 55.6 % male) with nonobstructive CAD, 68 (4.2 %) suffered MACE during a median follow-up of 28.6 months. After multivariable adjustment, PCATa was identified as an independent predictor (HR: 1.060, 95%CI: 1.025-1.096, p = 0.001). The inclusion of PCATa significantly enhanced the discrimination capacity [AUC:0.72 (0.66-0.78), p = 0.041] and risk reclassification (NRI = 1.99, p < 0.001; IDI = 0.93, p < 0.001) beyond the influence of clinical and CCTA factors. In the presence of HRP, a higher PCATa was found to be associated with a relatively higher risk of MACE compared to a lower PCATa (HR: 2.45, 95%CI: 1.09-5.52, p = 0.031).

CONCLUSIONS

PCATa is positively correlated with adverse outcome in patients with nonobstructive CAD, and it offers incremental predictive value beyond clinical variables and CCTA characteristics.

Right coronary artery pericoronary fat attenuation index as a future predictor for acute coronary events in nonobstructive coronary artery disease - a prospective single centre study

AIM

Evaluation of pericoronary adipose tissue changes induced by inflammation by non-invasive techniques is challenging.

PURPOSE

To find the association between pericoronary adipose tissue attenuation (FAI) changes and future acute coronary events in nonobstructive coronary artery disease.

MATERIALS AND METHODS

Ours was a single-centre, prospective observational study on patients with atypical chest pain who underwent coronary computed tomography angiography (CCTA). In patients with CADRADS 1 to 3 nonobstructive coronary artery disease (CAD), pericoronary FAI was measured around the proximal right coronary artery (RCA) and coronary artery segment with plaque using semi-automated postprocessing software. Patients were followed up for development of acute coronary events (ACE). Kaplan-Meier curves were used to see event-free survival rates.

RESULTS

Of 120 patients with a mean follow-up period of 67 months, 21 patients developed acute coronary events. RCA-FAI and lesion FAI of patients with ACE were significantly higher as compared to patients without events. ROC curve analysis showed RCA-FAI as the best predictor of ACE at a cut-off point of > -77.3 Hounsfield unit (HU) (with an AUC of 0.915) with high sensitivity (95.24%), specificity (83.84%), and negative predictive value (98.80%). On multivariate analysis, RCA-FAI, diabetes mellitus, and stenosis ≥50% were independent risk factors of ACE with hazard ratios of 1.335 (1.173-1.518), 4.950 (1.716-14.278), and 7.446 (2.257-24.566), respectively.

CONCLUSION

RCA FAI can predict ACE in nonobstructive coronary artery disease patients. Detection of high RCA FAI of > -77.3 HU on CCTA can help to identify high-risk patients who need regular follow-up and early initiation of interventions.