CT-derived epicardial adipose tissue density: Systematic review and meta-analysis

Coronary artery calcifications are not associated with epicardial adipose tissue volume and attenuation on computed tomography in 1,945 individuals with various degrees of glucose disorders

Background

The quantification of coronary artery calcifications (CAC) is a mainstay in radiological assessment of coronary atherosclerosis and cardiovascular risk, but reflect advanced, possibly late-stage changes in the arteries. Increased volume and changes in attenuation of the epicardial adipose tissue (EAT) on computed tomography (CT) have been linked to adverse cardiovascular events, and these changes in the EAT might reflect earlier stages of the processes leading to clinically manifest atherosclerosis. The relationship between EAT and CAC is subject to a knowledge gap, especially in individuals with no previously known coronary artery disease.

Methods

Fully automated EAT analysis with an artificial intelligence-based model was performed in a population sample enriched for pre-diabetics, comprising a total of 1,945 individuals aged 50-64 years, where non-contrast CT images, anthropometric and laboratory data was available on established cardiovascular risk factors. Uni- and multivariable linear regression, gradient-boosting and correlation analyses were performed to determine the explanatory value of EAT volume and attenuation data with regards to CAC data.

Results

Neither EAT volume nor EAT attenuation was associated with the presence or severity of CAC, when adjusting for established cardiovascular risk factors, and had only weak explanatory value in gradient-boosting and correlation analyses. Age was the strongest predictor of CAC in both sexes.

Conclusion

No independent association was found between CAC and total EAT volume or attenuation. Importantly, these findings do not rule out early stage or local effects on coronary atherosclerosis from the EAT immediately surrounding the coronary arteries.

Epicardial adipose tissue, cardiac damage, and mortality in patients undergoing TAVR for aortic stenosis

Computed tomography (CT)-derived Epicardial Adipose Tissue (EAT) is linked to cardiovascular disease outcomes. However, its role in patients undergoing Transcatheter Aortic Valve Replacement (TAVR) and the interplay with aortic stenosis (AS) cardiac damage (CD) remains unexplored. We aim to investigate the relationship between EAT characteristics, AS CD, and all-cause mortality. We retrospectively included consecutive patients who underwent CT-TAVR followed by TAVR. EAT volume and density were estimated using a deep-learning platform and CD was assessed using echocardiography. Patients were classified according to low/high EAT volume and density. All-cause mortality at 4 years was compared using Kaplan-Meier and Cox regression analyses. A total of 666 patients (median age 81 [74-86] years; 54% female) were included. After a median follow-up of 1.28 (IQR 0.53-2.57) years, 11.7% (n = 77) of patients died. The EAT volume (p = 0.017) decreased, and density increased (p < 0.001) with worsening AS CD. Patients with low EAT volume (< 49cm3) and high density (≥-86 HU) had higher all-cause mortality (log-rank p = 0.02 and p = 0.01, respectively), even when adjusted for age, sex, and clinical characteristics (HR 1.71, p = 0.02 and HR 1.73, p = 0.03, respectively). When CD was added to the model, low EAT volume (HR 1.67 p = 0.03) and CD stages 3 and 4 (HR 3.14, p = 0.03) remained associated with all-cause mortality. In patients with AS undergoing TAVR, CT-derived low EAT volume, and high density were independently associated with increased 4-year mortality and worse CD stage. Only EAT volume remained associated when adjusted for CD.

Correlation analysis between epicardial adipose tissue and acute coronary syndrome

To investigate the correlation between the density and volume of epicardial adipose tissue(EAT)and acute coronary syndrome (ACS). This study included 355 subjects (mean age: 60.65 ± 9.67 years; 54.65% male), comprising 175 patients with ACS and 180 without ACS. Propensity score matching was applied to balance the variables between the two groups, resulting in 96 successfully matched pairs. Clinical data, epicardial adipose tissue volume (EATV), and epicardial adipose tissue density (EATD) were compared. Independent factors influencing ACS were identified using logistic regression analysis, and the predictive ability of each variable was evaluated using receiver operating characteristic (ROC) curves. Systolic blood pressure, EATV, EATD, fasting blood glucose, triglycerides, and high-sensitivity C-reactive protein were significantly elevated in the ACS group compared with the non-ACS group (all p < 0.05). Spearman correlation analysis revealed a moderate positive correlation between EATV and BMI (r = 0.444, p < 0.001), while EATD showed a weak negative correlation with age (r = -0.177, p = 0.014) and a weak positive correlation with EATV (r = 0.239, p = 0.001). Univariable regression analysis demonstrated that both EATV (OR: 2.018, 95% CI: 1.334-3.052) and EATD (OR: 5.341, 95% CI: 3.293-8.663) were associated with ACS. After adjusting for other risk factors, logistic regression model confirmed that EATV (adjusted OR: 1.892, 95%CI: 1.211-2.955) and EATD (adjusted OR: 6.942, 95%CI: 3.875-12.437) were independent predictors of ACS (both p < 0.001), with EATD showing the highest predictive value (AUC = 0.859). This study identifies a close relationship between EAT and ACS, highlighting EATD and EATV as independent influencing factors for ACS. Among them, EATD demonstrated a stronger predictive value for ACS than both traditional risk factors and EATV.

Prognostic utility of dynamic changes in epicardial adipose tissue in patients undergoing transcatheter aortic valve replacement

BACKGROUND

Epicardial Adipose Tissue (EAT) volume is associated with the risk of cardiovascular events, which can be assessed by cardiac computed tomography. However, he optimal method and their prognostic utility in patients following transcatheter aortic valve replacement (TAVR) is unknown.

METHODS

We evaluated 258 participants, focusing on changes in EAT volume using cardiac CT enhancement. EAT volume was automatically computed as three-dimensional voxels between -190 to -30 HU on contrast-enhanced slices. Univariate and multivariable Cox regression analyses were conducted to assess the association of various clinical parameters and EAT volume indices with major adverse cardiovascular events (MACE).

RESULTS

During a median follow-up of 2.0 years [IQR, 1.8-2.3 years], 34 participants (median age 73 [IQR: -13.1 to -8.3) years, 55.4 % male) experiencing MACE. The optimal cutoff values for EAT volume change fraction (EATVCF) was 15.2 %, determined by the Youden-index. Kaplan-Meier curve analysis revealed that patients with high EATVCF were at higher risk (p < .01). In Cox regression, EATVCF (hazard ratio [HR]: 0.92, 95 % CI: 0.87 to 0.97, p = .001) remained significantly associated with MACE after adjusting for clinical factors. The addition of EATVCF to the clinical model increased the net Reclassification Improvement (NRI) by 30.1 % (95 % CI: 0.07-1.16).

CONCLUSION

EAT volume change fraction emerged as a significant predictor of MACE post-TAVR, highlighting the clinical value of EAT volume assessment in cardiovascular risk stratification.

Effect of Vessel Attenuation, VMI Level, and Reconstruction Kernel on Pericoronary Adipose Tissue Attenuation for EID CT and PCD CT: An Ex Vivo Porcine Heart Study

BACKGROUND. Pericoronary adipose tissue (PCAT) attenuation and the fat attenuation index (FAI) may serve as markers of inflammation and the risk of adverse cardiac events. However, standardization of relevant CT acquisition and reconstruction parameters is lacking. OBJECTIVE. The purpose of this study was to investigate the influence of vessel attenuation, the virtual monoenergetic image (VMI) level, and the reconstruction kernel on PCAT attenuation and FAI by use of energy-integrating detector (EID) and photon-counting detector (PCD) CT systems in an ex vivo porcine heart model. METHODS. The right coronary artery (RCA) of a porcine heart was injected with saline or varying contrast medium dilutions to achieve vessel attenuation ranging from 0 to 1000 HU. After each injection, the heart was sequentially scanned by EID CT at 120 kVp and PCD CT at 140 kVp at a constant CTDIvol of 10 mGy. For EID CT, polychromatic images were reconstructed with a Qr40 kernel. For PCD CT, VMIs (obtained at 40-80 keV in 10-keV increments) were reconstructed with Qr40, Bv40, and Bv56 kernels. ROIs were placed to measure RCA and PCAT attenuation. FAI was determined using software; histogram analysis was performed to assess voxel attenuation in the volumes of interest for FAI calculation. RESULTS. Correlations were observed between attenuation in the RCA and attenuation in the adjacent PCAT (r = 0.3-1.0) and between vessel attenuation and the FAI (r = -0.9 to 1.0). For PCAT attenuation and the FAI, these associations became progressively weaker when progressively sharper kernels were used. For increasing vessel attenuation on EID CT and for increasing VMI level on PCD CT, FAI histograms showed right shifts in peak attenuation values; the percentage of histogram voxels that met the threshold range for inclusion in FAI calculation was 9-38% for EID CT and 6-39% for PCD CT at VMI levels of 70-80 keV. For PCD CT, use of sharper kernels was associated with left shifts in peak attenuation values and greater percentages of voxels within the threshold range for inclusion in FAI calculation. CONCLUSION. PCAT attenuation and the FAI are influenced by vessel lumen attenuation, the VMI level, and the reconstruction kernel. A minority of pericoronary voxels contribute to FAI measurements for polychromatic EID CT and for PCD CT at high VMI levels. CLINICAL IMPACT. These findings may help standardize acquisition and reconstruction parameters for PCAT attenuation and FAI measurements.

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.

Association of epicardial adipose tissue density with postoperative atrial fibrillation after isolated aortic valve replacement

Backgrounds

It is well known that epicardial adipose tissue (EAT) is associated with the development of atrial fibrillation (AF). The aim of this study was to investigate whether EAT density (EAT-d) is associated with the development of new-onset atrial fibrillation (POAF) after aortic valve replacement (AVR).

Methods

We retrospectively studied 143 patients who underwent simple AVR at Department of Cardiovascular Surgery of the General Hospital of Northern Theater Command between June 2020 to August 2023. All patients received cardiac coronary artery computed tomography (CT) before surgery. EAT-d, EAT volume and EAT volume index (EATVI) were quantitatively measured and analysed using EAT analysis software (TIMESlicePro). POAF was detected by 7-day Holter monitoring.

Results

Of 143 patients undergoing AVR, 55 patients (38.46 %) developed POAF after surgery. Male patients and patients who had elder age or smoking history were more likely to develop POAF. On univariable analysis, patients developed POAF had significantly more EAT-d (-79.19(-83.91, -74.69) vs. -81.54(-87.16, -76.76); P = 0.043) and EATVI (4.14(3.32,5.03) vs. 3.90(2.70,4.51); P = 0.043) than patients without POAF. On multivariable analysis, EAT-d and age were independent risk factors for POAF (odds ratio (OR): 1.186, 95 % confidence interval (CI): 1.062-1.324, P = 0.002; OR: 1.119, 95 %CI: 1.055-1.187, P < 0.001). Furthermore, EAT-d was significantly associated with age. Furthermore, EAT-d was associated with cardiac structure changes, such as cardiac left ventricular end-diastolic, left ventricular end-systolic volumes and NT-proBNP before surgery.

Conclusion

EAT-d and age are independent predictors of POAF after simple AVR. EAT-d was related with age.

Relationship between epicardial adipose tissue and coronary atherosclerosis by CCTA in young adults (18-45)

Objective

Epicardial adipose tissue (EAT) is implicated in the pathogenesis and progression of coronary artery disease (CAD). Limited data exists on the interplay between EAT and atherosclerosis in young individuals. Our study aims to explore the relationship between EAT and CAD in a young cohort.

Methods

All young (18-45 years) patients without prior CAD, referred for coronary computed tomography angiography (CCTA) from 2016 to 2022 were included. EAT volume and coronary artery calcium (CAC) were calculated from dedicated non-contrast scans. Coronary plaque presence, extent, and volume were quantified from CCTA. Multivariable logistic regression models for the presence of CAD, defined as any coronary atherosclerosis, were performed.

Results

Overall, 712 patients (39±4.8 years, 54 % female) with 45 % Hispanic, and 21 % non-Hispanic Black were included. Patients with CAD had higher EAT volume than those without (80.80 mL ± 36.00 vs 55.16 mL ± 27.92; P < 0.001). In those with CAC=0, higher EAT was associated with the presence of CAD compared to lower EAT volume (P < 0.001). An EAT volume >76 mL was associated with higher CAC (P < 0.001), segment involvement score (P < 0.001), and quantitative total, non-calcified, and low-attenuation plaque volumes (P < 0.002). At multivariable analysis, EAT volume (per 10 mL, OR: 1.21; 95 %CI: 1.12-1.30; P < 0.0001) was independently associated with the presence of CAD.

Conclusion

In a diverse cohort of young adults without history of CAD and undergoing a clinically indicated CCTA, EAT volume was independently associated with the presence of CAD. Our findings highlight EAT potential as a novel marker for CAD risk-assessment and a potential therapeutic target in young patients.

Epicardial adipose tissue volume and density are associated with heart failure with improved ejection fraction

BACKGROUND

Heart failure (HF) with improved ejection fraction (EF, HFimpEF) is a distinct HF subtype, characterized by left ventricular (LV) reverse remodeling and myocardial functional recovery. Multiple cardiometabolic factors are implicated in this process. Epicardial adipose tissue (EAT), emerging as an endocrine and paracrine organ, contributes to the onset and progression of HF. However, the relation between EAT and the incidence of HFimpEF is still unclear.

METHODS

A total of 203 hospitalized HF patients with reduced EF (HFrEF, LVEF ≤ 40%) who underwent coronary CT angiography (CCTA) during index hospitalization were consecutively enrolled between November 2011 and December 2022. Routine follow-up and repeat echocardiograms were performed. The incidence of HFimpEF was defined as (1) an absolute LVEF improvement ≥ 10% and (2) a second LVEF > 40% (at least 3 months apart). EAT volume and density were semiautomatically quantified on non-enhanced series of CCTA scans.

RESULTS

During a median follow-up of 8.6 (4.9 ~ 13.3) months, 104 (51.2%) patients developed HFimpEF. Compared with HFrEF patients, HFimpEF patients had lower EAT volume (115.36 [IQR 87.08 ~ 154.78] mL vs. 169.67 [IQR 137.22 ~ 218.89] mL, P < 0.001) and higher EAT density (-74.92 ± 6.84 HU vs. -78.76 ± 6.28 HU, P < 0.001). Multivariate analysis showed lower EAT volume (OR: 0.885 [95%CI 0.822 ~ 0.947]) and higher density (OR: 1.845 [95%CI 1.023 ~ 3.437]) were both independently associated with the incidence of HFimpEF. Subgroup analysis revealed that the association between EAT properties and HFimpEF was not modified by HF etiology.

CONCLUSIONS

This study reveals that lower EAT volume and higher EAT density are associated with development of HFimpEF. Therapies targeted at reducing EAT quantity and improving its quality might provide favorable effects on myocardial recovery in HF patients.

Epicardial and pericoronary adipose tissue and coronary plaque burden in patients with Cushing's syndrome: a propensity score-matched study

PURPOSE

To assess coronary inflammation by measuring the volume and density of the epicardial adipose tissue (EAT), perivascular fat attenuation index (FAI) and coronary plaque burden in patients with Cushing's syndrome (CS) based on coronary computed tomography angiography (CCTA).

METHODS

This study included 29 patients with CS and 58 matched patients without CS who underwent CCTA. The EAT volume, EAT density, FAI and coronary plaque burden were measured. The high-risk plaque (HRP) was also evaluated. CS duration from diagnosis, 24-h urinary free cortisol (UFC), and abdominal visceral adipose tissue volume (VAT) of CS patients were recorded.

RESULTS

The CS group had higher EAT volume (146.9 [115.4, 184.2] vs. 119.6 [69.0, 147.1] mL, P = 0.006), lower EAT density (- 78.79 ± 5.89 vs. - 75.98 ± 6.03 HU, P = 0.042), lower FAI (- 84.0 ± 8.92 vs. - 79.40 ± 10.04 HU, P = 0.038), higher total plaque volume (88.81 [36.26, 522.5] vs. 44.45 [0, 198.16] mL, P = 0.010) and more HRP plaques (7.3% vs. 1.8%, P = 0.026) than the controls. The multivariate analysis suggested that CS itself (β [95% CI], 29.233 [10.436, 48.03], P = 0.014), CS duration (β [95% CI], 0.176 [0.185, 4.242], P = 0.033), and UFC (β [95% CI], 0.197 [1.803, 19.719], P = 0.019) were strongly associated with EAT volume but not EAT density, and EAT volume (β [95% CI] - 0.037[- 0.058, - 0.016], P = 0.001) not CS was strongly associated with EAT density. EAT volume, FAI and plaque burden increased (all P < 0.05) in 6 CS patients with follow-up CCTA. The EAT volume had a moderate correlation with abdominal VAT volume (r = 0.526, P = 0.008) in CS patients.

CONCLUSIONS

Patients with CS have higher EAT volume and coronary plaque burden but less inflammation as detected by EAT density and FAI. The EAT density is associated with EAT volume but not CS itself.

Quality of epicardial adipose tissue predicts major adverse cerebral and cardiovascular events following transcatheter aortic valve implantation

Epicardial adipose tissue (EAT) have been shown to be associated with several heart disease, including coronary artery disease (CAD), atrial fibrillation (AF), and heart failure (HF). It is reported that the quality of EAT, represented by fat attenuation determined using computed tomography (CT) imaging, can detect the histologically-assessed remodeled EAT. We tested the hypothesis that quality of EAT would predict major adverse cerebral and cardiovascular events (MACCE) following transcatheter aortic valve implantation (TAVI) in patients with aortic stenosis (AS). A total of 125 consecutive severe AS patients who underwent TAVI were enrolled (39 male, mean 85.4 ± 4.0 years). Using CT imaging before TAVI, we measured the average CT fat attenuation of EAT (EAT attenuation) and investigated the association with MACCE. During the mean follow up period of 567 ± 371 days, 21 cases of MACCE were observed. Patients with MACCE had greater levels of EAT attenuation compared to those without (- 74 ± 3.7 Hounsfield Units (HU) vs - 77 ± 5.5 HU, p = 0.010). Based on the ROC curves, the high EAT attenuation was defined as > - 74.3 HU. According to this cut-off index, 44 patients were classified into the high EAT attenuation group (28 female, mean age 87 ± 3.6 years), whereas 81 patients were classified into the low EAT attenuation group (13 female, 85 ± 4.1 years). Kaplan-Meier survival curve demonstrated that the patients in the high EAT attenuation group showed greater prevalence of MACCE (log-rank 6.64, p = 0.010). Cox proportional hazards regression analysis revealed that EAT attenuation and Logistic EuroSCORE were independently associated with the incidence of MACCE. Our results suggest that quality of EAT, assessed by EAT attenuation detected by CT imaging, can predict the cerebral and cardiovascular events after TAVI in patients with AS.

CT radiomic features reproducibility of virtual non-contrast series derived from photon-counting CCTA datasets using a novel calcium-preserving reconstruction algorithm compared with standard non-contrast series: focusing on epicardial adipose tissue

PURPOSE

We aimed to evaluate the reproducibility of computed tomography (CT) radiomic features (RFs) about Epicardial Adipose Tissue (EAT). The features derived from coronary photon-counting computed tomography (PCCT) angiography datasets using the PureCalcium (VNCPC) and conventional virtual non-contrast (VNCConv) algorithm were compared with true non-contrast (TNC) series.

METHODS

RFs of EAT from 52 patients who underwent PCCT were quantified using VNCPC, VNCConv, and TNC series. The agreement of EAT volume (EATV) and EAT density (EATD) was evaluated using Pearson's correlation coefficient and Bland-Altman analysis. A total of 1530 RFs were included. They are divided into 17 feature categories, each containing 90 RFs. The intraclass correlation coefficients (ICCs) and concordance correlation coefficients (CCCs) were calculated to assess the reproducibility of RFs. The cutoff value considered indicative of reproducible features was > 0.75.

RESULTS

the VNCPC and VNCConv tended to underestimate EATVs and overestimate EATDs. Both EATV and EATD of VNCPC series showed higher correlation and agreement with TNC than VNCConv series. All types of RFs from VNCPC series showed greater reproducibility than VNCConv series. Across all image filters, the Square filter exhibited the highest level of reproducibility (ICC = 67/90, 74.4%; CCC = 67/90, 74.4%). GLDM_GrayLevelNonUniformity feature had the highest reproducibility in the original image (ICC = 0.957, CCC = 0.958), exhibiting a high degree of reproducibility across all image filters.

CONCLUSION

The accuracy evaluation of EATV and EATD and the reproducibility of RFs from VNCPC series make it an excellent substitute for TNC series exceeding VNCConv series.

Role of epicardial adipose tissue in diabetic cardiomyopathy through the lens of cardiovascular magnetic resonance imaging - a narrative review

Accumulating evidence suggests that ectopic/visceral adiposity may play a key role in the pathogenesis of nonischaemic cardiovascular diseases associated with type 2 diabetes. Epicardial adipose tissue (EAT) is a complex visceral fat depot, covering 80% of the cardiac surface with anatomical and functional contiguity to the myocardium and coronary arteries. EAT interacts with the biology of the underlying myocardium by secreting a wide range of adipokines. Magnetic resonance imaging (MRI) is the reference modality for structural and functional imaging of the heart. The technique is now also emerging as the reference imaging modality for EAT quantification. With this narrative review, we (a) surveyed contemporary clinical studies that utilized cardiovascular MRI to characterize EAT (studies published 2010-2023); (b) listed the clinical trials monitoring the response to treatment in EAT size as well as myocardial functional and structural parameters and (c) discussed the potential pathophysiological role of EAT in the development of diabetic cardiomyopathy. We concluded that increased EAT quantity and its inflammatory phenotype correlate with early signs of left ventricle dysfunction and may have a role in the pathogenesis of cardiac disease in diabetes with and without coronary artery disease.

CT Images in Follicular Lymphoma: Changes after Treatment Are Predictive of Cardiac Toxicity in Patients Treated with Anthracycline-Based or R-B Regimens

The aim of this study is to evaluate changes in epicardial adipose tissue (EAT) and cardiac extracellular volume (ECV) in patients with follicular lymphoma (FL) treated with R-CHOP-like regimens or R-bendamustine. We included 80 patients with FL between the ages of 60 and 80 and, using computed tomography (CT) performed at onset and at the end of treatment, we assessed changes in EAT by measuring tissue density at the level of the cardiac apex, anterior interventricular sulcus and posterior interventricular sulcus of the heart. EAT is known to be associated with metabolic syndrome, increased calcium in the coronary arteries and therefore increased risk of coronary artery disease. We also evaluated changes in ECV, which can be used as an early imaging marker of cardiac fibrosis and thus myocardial damage. The R-CHOP-like regimen was associated with lower EAT values (p < 0.001), indicative of a less active metabolism and more adipose tissue, and an increase in ECV (p < 0.001). Furthermore, in patients treated with anthracyclines and steroids (R-CHOP-like) there is a greater decrease in ejection fraction (EF p < 0.001) than in the R-B group. EAT and ECV may represent early biomarkers of cardiological damage, and this may be considered, to our knowledge, the first study investigating radiological and cardiological parameters in patients with FL.

Relationships of pericoronary and epicardial fat measurements in male and female patients with and without coronary artery disease

INTRODUCTION

Although pericoronary adipose tissue (PCAT) is a component of the epicardial adipose tissue (EAT) depot, they may have different associations to coronary artery disease (CAD). We explored relationships between pericoronary adipose tissue mean attenuation (PCATMA) and EAT measurements in coronary CT angiography (CCTA) in patients with and without CAD.

MATERIAL AND METHODS

CCTA scans of 185 non-CAD and 81 CAD patients (86.4% >50% stenosis) were included and retrospectively analyzed. PCATMA and EAT density/volume were measured and analyzed by sex, including associations with age, risk factors and tube voltage using linear regression models.

RESULTS

In non-CAD and CAD, mean PCATMA and EAT volume were higher in men than in women (non-CAD: -92.5 ± 10.6HU vs -96.2 ± 8.4HU, and 174.4 ± 69.1 cm3 vs 124.1 ± 57.3 cm3; CAD: -92.2 ± 9.0HU vs -97.4 ± 9.7HU, and 193.6 ± 62.5 cm3 vs 148.5 ± 50.5 cm3 (p < 0.05)). EAT density was slightly lower in men than women in non-CAD (-96.4 ± 6.3HU vs -94.4 ± 5.5HU (p < 0.05)), and similar in CAD (-98.2 ± 5.2HU vs 98.2 ± 6.4HU). There was strong correlation between PCATMA and EAT density (non-CAD: r = 0.725, p < 0.001, CAD: r = 0.686, p < 0.001) but no correlation between PCATMA and EAT volume (non-CAD: r = 0.018, p = 0.81, CAD: r = -0.055, p = 0.63). A weak inverse association was found between EAT density and EAT volume (non-CAD: r = -0.244, p < 0.001, CAD: r = -0.263, p = 0.02). In linear regression models, EAT density was significantly associated with PCATMA in both non-CAD and CAD patients independent of risk factors and tube voltage.

CONCLUSION

In CAD and non-CAD patients, EAT density, but not EAT volume, showed significant associations with PCATMA. Compared to women, men had higher PCATMA and EAT volume independently of disease status, but similar or slightly lower EAT density. Differences in trends and relations of PCATMA and EAT by sex could indicate that personalized interpretation and thresholding is needed.

Epicardial Adipose Tissue Assessed by Computed Tomography and Echocardiography Are Associated With Adverse Cardiovascular Outcomes: A Systematic Review and Meta-Analysis

BACKGROUND

Epicardial adipose tissue (EAT) has garnered attention as a prognostic and risk stratification factor for cardiovascular disease. This study, via meta-analyses, evaluates the associations between EAT and cardiovascular outcomes stratified across imaging modalities, ethnic groups, and study protocols.

METHODS

Medline and Embase databases were searched without date restriction on May 2022 for articles that examined EAT and cardiovascular outcomes. The inclusion criteria were (1) studies measuring EAT of adult patients at baseline and (2) reporting follow-up data on study outcomes of interest. The primary study outcome was major adverse cardiovascular events. Secondary study outcomes included cardiac death, myocardial infarction, coronary revascularization, and atrial fibrillation.

RESULTS

Twenty-nine articles published between 2012 and 2022, comprising 19 709 patients, were included in our analysis. Increased EAT thickness and volume were associated with higher risks of cardiac death (odds ratio, 2.53 [95% CI, 1.17-5.44]; P=0.020; n=4), myocardial infarction (odds ratio, 2.63 [95% CI, 1.39-4.96]; P=0.003; n=5), coronary revascularization (odds ratio, 2.99 [95% CI, 1.64-5.44]; P<0.001; n=5), and atrial fibrillation (adjusted odds ratio, 4.04 [95% CI, 3.06-5.32]; P<0.001; n=3). For 1 unit increment in the continuous measure of EAT, computed tomography volumetric quantification (adjusted hazard ratio, 1.74 [95% CI, 1.42-2.13]; P<0.001) and echocardiographic thickness quantification (adjusted hazard ratio, 1.20 [95% CI, 1.09-1.32]; P<0.001) conferred an increased risk of major adverse cardiovascular events.

CONCLUSIONS

The utility of EAT as an imaging biomarker for predicting and prognosticating cardiovascular disease is promising, with increased EAT thickness and volume being identified as independent predictors of major adverse cardiovascular events.

REGISTRATION

URL: https://www.crd.york.ac.uk/prospero; Unique identifier: CRD42022338075.

Assessment of epicardial adipose tissue on virtual non-contrast images derived from photon-counting detector coronary CTA datasets

OBJECTIVES

To assess epicardial adipose tissue (EAT) volume and attenuation of different virtual non-contrast (VNC) reconstructions derived from coronary CTA (CCTA) datasets of a photon-counting detector (PCD) CT-system to replace true non-contrast (TNC) series.

METHODS

Consecutive patients (n = 42) with clinically indicated CCTA and coronary TNC were included. Two VNC series were reconstructed, using a conventional (VNC_Conv) and a novel calcium-preserving (VNC_PC) algorithm. EAT was segmented on TNC, VNC_Conv, VNC_PC, and CCTA (CTA_-30) series using thresholds of -190 to -30 HU and an additional segmentation on the CCTA series with an upper threshold of 0 HU (CTA₀). EAT volumes and their histograms were assessed for each series. Linear regression was used to correlate EAT volumes and the Euclidian distance for histograms. The paired t-test and the Wilcoxon signed-rank test were used to assess differences for parametric and non-parametric data.

RESULTS

EAT volumes from VNC and CCTA series showed significant differences compared to TNC (all p < .05), but excellent correlation (all R² > 0.9). Measurements on the novel VNC_PC series showed the best correlation (R² = 0.99) and only minor absolute differences compared to TNC values. Mean volume differences were -12%, -3%, -13%, and +10% for VNC_Conv, VNC_PC, CTA_-30, and CTA₀ compared to TNC. Distribution of CT values on VNC_PC showed less difference to TNC than on VNC_Conv (mean attenuation difference +7% vs. +2%; Euclidean distance of histograms 0.029 vs. 0.016).

CONCLUSIONS

VNC_PC-reconstructions of PCD-CCTA datasets can be used to reliably assess EAT volume with a high accuracy and only minor differences in CT values compared to TNC. Substitution of TNC would significantly decrease patient's radiation dose.

KEY POINTS

• Measurement of epicardial adipose tissue (EAT) volume and attenuation are feasible on virtual non-contrast (VNC) series with excellent correlation to true non-contrast series (all R²>0.9). • Differences in VNC algorithms have a significant impact on EAT volume and CT attenuation values. • A novel VNC algorithm (VNC_PC) enables reliable assessment of EAT volume and attenuation with superior accuracy compared to measurements on conventional VNC- and CCTA-series.

Cardiac Computed Tomography Evaluation of Association of Left Ventricle Disfunction and Epicardial Adipose Tissue Density in Patients with Low to Intermediate Cardiovascular Risk

Background and objectives: Epicardial adipose tissue density (EAD) has been associated with coronary arteries calcium score, a higher load of coronary artery disease (CAD) and plaque vulnerability. This effect can be related to endocrine and paracrine effect of molecules produced by epicardial adipose tissue (EAT), that may influence myocardial contractility. Using coronary computed tomography angiography (CCT) the evaluation of EAD is possible in basal scans. The aim of the study is to investigate possible associations between EAD and cardiac function. Material and Methods: 93 consecutive patients undergoing CCT without and with contrast medium for known or suspected coronary CAD were evaluated. EAD was measured on basal scans, at the level of the coronary ostia, the lateral free wall of the left ventricle, at the level of the cardiac apex, and at the origin of the posterior interventricular artery. Cardiac function was evaluated in post-contrast CT scans in order to calculate ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), and stroke volume (SV). Results: A statistically significant positive correlation between EAD and ejection fraction (r = 0.29, p-value < 0.01) was found. Additionally, a statistically significant negative correlation between EAD and ESV (r = -0.25, p-value < 0.01) was present. Conclusion: EAD could be considered a new risk factor associated with reduced cardiac function. The evaluation of this parameter with cardiac CT in patients with low to intermediate cardiovascular risk is possible.

Epicardial Adipose Tissue: A Novel Potential Imaging Marker of Comorbidities Caused by Chronic Inflammation

The observation of correlations between obesity and chronic metabolic and cardiovascular diseases has led to the emergence of strong interests in “adipocyte biology”, in particular in relation to a specific visceral adipose tissue that is the epicardial adipose tissue (EAT) and its pro-inflammatory role. In recent years, different imaging techniques frequently used in daily clinical practice have tried to obtain an EAT quantification. We provide a useful update on comorbidities related to chronic inflammation typical of cardiac adiposity, analyzing how the EAT assessment could impact and provide data on the patient prognosis. We assessed for eligibility 50 papers, with a total of 10,458 patients focusing the review on the evaluation of EAT in two main contexts: cardiovascular and metabolic diseases. Given its peculiar properties and rapid responsiveness, EAT could act as a marker to investigate the basal risk factor and follow-up conditions. In the future, EAT could represent a therapeutic target for new medications. The assessment of EAT should become part of clinical practice to help clinicians to identify patients at greater risk of developing cardiovascular and/or metabolic diseases and to provide information on their clinical and therapeutic outcomes.