Epicardial Fat Volume Research Articles

Coronary Computed Tomography Angiography in Heart Transplant Patients: Current Insights and Future Directions

Cardiac allograft vasculopathy (CAV) remains a significant challenge after heart transplantation, necessitating effective surveillance methods. This review centers around the role of coronary computed tomography angiography (CCTA) in CAV surveillance, given its unique capabilities to visualize and quantify CAV in comparison with other imaging modalities, including invasive coronary angiography and intravascular ultrasound. CCTA has shown good diagnostic performance for detecting and monitoring CAV, exemplified by a higher sensitivity and negative predictive value compared with invasive coronary angiography. Additionally, CCTA can provide valuable functional insights with fractional flow reserve integration. An additional, considerable benefit of CCTA is that it allows for the opportunity to assess other imaging markers of cardiometabolic and general health, including coronary artery calcium score, epicardial fat volume, liver fat, vertebral bone density, and lung density, which allows for a comprehensive assessment of the overall health of the patient.

Noninvasive predictors of residual coronary microvascular dysfunction after elective percutaneous coronary intervention

Abstract Backgrounds Coronary computed tomographic angiography (CCTA) provides noninvasive assessments of coronary plaque morphologies and perivascular inflammation. Morphological features associated with residual coronary microvascular dysfunction (CMD) after elective percutaneous coronary intervention (PCI) remains unknown. Purpose This study aimed to examine prevalence and predictors of residual CMD and its phenotypes after elective PCI. Methods We investigated consecutive patients who were scheduled for elective fractional flow reserve (FFR)-guided PCI for de novo single lesions with pre-PCI CCTA data. Pre- and post-PCI comprehensive physiological assessments including coronary flow reserve (CFR) and index of microcirculatory resistance (IMR) were performed by using pressure temperature sensor-tipped guidewire in all patients. Patients with periprocedural myocardial infarction were excluded. Residual CMD was defined as lesions with post-PCI coronary flow reserve (CFR) <2.0, which was further categorized as functional (IMR<25) or structural (IMR ≥25) CMD. Results A total of 198 de novo lesions in 198 patients were included in the final dataset. Pre- and post-PCI mean CFR were 1.79 [1.27, 2.53] and 2.72 [2.00, 4.04], respectively. Residual CMD was observed in 24.7% (49/198) of patients, categorized as functional (n=26) or structural (n=23). Patients with residual CMD showed older age, less frequent diabetes mellitus, current smoking and a culprit lesion in left anterior descending artery (LAD), and higher CCTA-defined calcium score in the culprit vessel compared with those in patients without residual CMD. Multivariable logistic regression analysis showed that age (adjusted odds ratio [OR]:1.04; 95% confidence interval [CI]: 1.00 to 1.08; p=0.04) and non-LAD (adjusted OR: 2.18; 95%CI: 1.03 to 4.63; p=0.04) were independently associated with residual CMD. In patients with residual CMD, patients with structural CMD tended to have more frequent diabetes mellitus (43.5% vs 19.2%, P=0.13) and atrial fibrillation (26.1% vs 7.7%) and showed significantly lower pericoronary adipose tissue attenuation (PCATA) in right coronary artery (RCA) by CCTA (-79.9 HU vs -74.6 HU, P=0.04) compared with patients with functional CMD. CCTA-detected epicardial fat volume and attenuation showed no significant differences between patients with residual functional CMD, those with residual structural CMD, and those without residual CMD. Multivariable analysis revealed that diabetes mellitus (adjusted OR: 5.18; 95%CI: 1.14 to 23.7; p=0.03) and PCATA in RCA (adjusted OR: 0.93; 95% CI: 0.85 to 1.00; p=0.05) were independently predictive of residual structural CMD. Conclusions Residual CMD was observed in approximately 25% of patients undergoing elective PCI. CCTA-defined calcium score and PCATA, along with clinical factors could be potential predictors of post-PCI residual CMD and its phenotypes.

Impact of body mass index on the relationship of Epicardial fat volume to coronary artery disease in males

BackgroundEpicardial fat tissue refers to a type of visceral fat tissue that envelops the myocardial and visceral pericardium. It is recognized as a novel risk sign for cardiovascular issues, including coronary artery disease, our aim to assess the influence of body mass index on the amount of epicardial fat volume and its association with coronary artery disease in male patients.MethodsEpicardial fat volume was quantified using cardiac Computed tomography scans in a cohort of 119 male patients who were believed to have coronary artery disease. Patients were categorized into three groups based on their body mass index values: Group I Body Mass Index (BMI ≥ 18.5–24.9 kg/m2), Group II (BMI ≥ 25–29.9 kg/m2), and Group III (BMI ≥ 30 kg/m2).ResultsIn Group I, there were twenty-three patients (19.3%) with a mean epicardial fat volume of 40 ± .42.8 ml. In Group II, there were forty-three patients (36%) with a mean Epicardial Fat Volume (EFV) of 56 ± 21.5 ml. In Group III, there were 53 patients (44%) with a mean EFV of 56 ± 15.8 ml, when compared to the results of Group I, which were considerably higher (p = 0.0004). Regarding prevalence of obstructive coronary artery disease in our patient population, 86 individuals (72.3%) were diagnosed with obstructive coronary artery disease and exhibited a tendency to have a greater value of epicardial fat volume at 56.4 ± 18.9 ml, with a range of 19–121 ml, compared to those without coronary artery disease at 45.2 ± 6.7 ml, with a range of 33–55 ml (P < 0.02). The prevalence of coronary artery disease was 85% in group III and 87% in group II. Patients in group III with coronary artery disease exhibited a substantially higher EFV of 46 ± 6.63 vs 16 ± 3.2 ml (p = 0.001) compared to those without obstructive coronary artery disease.ConclusionsAlthough epicardial fat volume was elevated in patients with coronary artery disease independent of their BMI, the predictive ability of epicardial fat volume for coronary artery disease was more pronounced in individuals with a body mass index more than 25 kg/m2.

Quantitative investigation of acute lesions created by ethanol infusion into the vein of Marshall

BackgroundEthanol infusion into the vein of Marshall (EIVOM) has been performed as an adjunctive atrial fibrillation therapy. However, the time course change, quantitative lesion investigation, and effects on epicardial fat pads and fractionated atrial electrograms created by EIVOM have never been investigated. ObjectiveThis study aimed to perform a quantitative analysis of lesions created by EIVOM. MethodsWe created voltage maps using a 3-dimensional mapping system immediately before and 30 minutes and 60 minutes after performing EIVOM to study the time course change in the lesions. We compared differences in the average contact force value required for successful conduction block in the Marshall vein area of patients with and without EIVOM. We also investigated effects of EIVOM on the area of complex fractionated atrial electrograms before and after EIVOM. We measured the total epicardial fat pad volume before and after EIVOM by computed tomography. ResultsVoltage was significantly reduced after EIVOM, and there were significant differences in voltage reduction between the control status and 30 minutes and 60 minutes after EIVOM (P < .05). The average contact force value was significantly lower with vs without EIVOM (P < .05). The total epicardial fat volume and complex fractionated atrial electrogram area also significantly decreased after EIVOM (P < .05). ConclusionEIVOM provided significant therapeutic effects on the left atrial tissue perpetuating atrial fibrillation, which was demonstrated by a quantitative analysis.

Epicardial fat modifies the relationship between coronary calcium score and all-cause mortality: The St. Francis Heart Study

ObjectiveEpicardial fat is associated with cardiovascular risk factors and adverse outcomes. However, it is not clear if epicardial fat remains to be a mortality risk when coronary calcium score (CAC) is taken into account. MethodsWe studied the 1005 participants from the St. Francis Heart Study who were apparently healthy with CAC scores at 80th percentile or higher for age and gender, randomly assigned to placebo or statin therapy. At baseline, lipid profiles and non-contrast CT images were obtained where the epicardial fat volume was analyzed. Likelihood ratio testing was used to assess the additional prognostic value of epicardial fat to CAC for the risk of all-cause mortality. ResultsIncreased epicardial fat volume was associated with higher CAC. For each unit increase in lnCAC, the average epicardial fat volume increased by 3.34 mL/m2. After a mean follow-up period of 17 years, 179 (18%) participants died. Increased epicardial fat volume was associated with an adjusted hazard ratio of 1.11 (95% CI: 1.02 to 1.20) predicting all-cause mortality. In the stratified analysis testing strata of epicardial fat and CAC, those with increased epicardial fat and increased CAC had the highest risk of death. Compared with a model containing lnCAC and traditional risk factors, a model additionally containing epicardial fat volume yielded a better model fit (likelihood ratio test p < 0.001). ConclusionIncreased epicardial fat volume is associated with increased all-cause mortality risk. In addition, it portends incremental prognostic value to CAC score in mortality prediction.

Epicardial fat volume is associated with primary coronary slow-flow phenomenon in patients with severe aortic stenosis undergoing transcatheter valve implantation

BackgroundPrimary coronary slow flow (CSF) is defined as delayed opacification of the distal epicardial vasculature during coronary angiography in the absence of relevant coronary artery stenoses. Microvascular disease is thought to be the underlying cause of this pathology. Epicardial fat tissue (EFT) is an active endocrine organ directly surrounding the coronary arteries that provides pro-inflammatory factors to the adjacent tissue by paracrine and vasocrine mechanisms. The aim of the present study was to investigate a potential association between EFT and primary CSF and whether EFT can predict the presence of primary CSF.MethodsBetween 2016 and 2017, n = 88 patients with high-grade aortic stenosis who were planned for transcatheter aortic valve implantation (TAVI) were included in this retrospective study. EFT volume was measured by pre-TAVI computed tomography (CT) using dedicated software. The presence of primary CSF was defined based on the TIMI frame count from the pre-TAVI coronary angiograms.ResultsThirty-nine of 88 TAVI patients had CSF (44.3%). EFT volume was markedly higher in patients with CSF (142 ml [IQR 107–180] vs. 113 ml [IQR 89–147]; p = 0.009) and was strongly associated with the presence of CSF (OR 1.012 [95%CI 1.002–1.021]; p = 0.014). After adjustment, EFT volume was still an independent predictor of CSF (OR 1.016 [95%CI 1.004–1.026]; p = 0.009).ConclusionPrimary CSF was independently associated with increased EFT volume. Further studies are needed to validate this finding and elucidate whether a causal relationship exists.

Bariatric surgery partially reverses subclinical proarrhythmic structural, electrophysiological, and autonomic changes in obesity

BackgroundObesity confers higher risks of cardiac arrhythmias. The extent to which weight loss reverses subclinical proarrhythmic adaptations in arrhythmia-free obese individuals is unknown. ObjectiveThe purpose of this study was to study structural, electrophysiological, and autonomic remodeling in arrhythmia-free obese patients and their reversibility with bariatric surgery using electrocardiographic imaging (ECGi). MethodsSixteen arrhythmia-free obese patients (mean age 43 ± 12 years; 13 (81%) female participants; BMI 46.7 ± 5.5 kg/m2) had ECGi pre–bariatric surgery, of whom 12 (75%) had ECGi postsurgery (BMI 36.8 ± 6.5 kg/m2). Sixteen age- and sex-matched lean healthy individuals (mean age 42 ± 11 years; BMI 22.8 ± 2.6 kg/m2) acted as controls and had ECGi only once. ResultsObesity was associated with structural (increased epicardial fat volumes and left ventricular mass), autonomic (blunted heart rate variability), and electrophysiological (slower atrial conduction and steeper ventricular repolarization time gradients) remodeling. After bariatric surgery, there was partial structural reverse remodeling, with a reduction in epicardial fat volumes (68.7 cm3 vs 64.5 cm3; P = .0010) and left ventricular mass (33 g/m2.7 vs 25 g/m2.7; P < .0005). There was also partial electrophysiological reverse remodeling with a reduction in mean spatial ventricular repolarization gradients (26 mm/ms vs 19 mm/ms; P = .0009), although atrial activation remained prolonged. Heart rate variability, quantified by standard deviation of successive differences in R-R intervals, was also partially improved after bariatric surgery (18.7 ms vs 25.9 ms; P = .017). Computational modeling showed that presurgical obese hearts had a larger window of vulnerability to unidirectional block and had an earlier spiral-wave breakup with more complex reentry patterns than did postsurgery counterparts. ConclusionObesity is associated with adverse electrophysiological, structural, and autonomic remodeling that is partially reversed after bariatric surgery. These data have important implications for bariatric surgery weight thresholds and weight loss strategies.

Association of epicardial fat volume with subclinical myocardial damage in patients with type 2 diabetes mellitus.

In type 2 diabetes mellitus (T2DM) patients, left ventricular systolic dyssynchrony (LVSD) with normal left ventricular ejection fraction (LVEF) and normal myocardial perfusion could referred to as subclinical myocardial damage, which is difficult to diagnose at an early stage. Epicardial adipose tissue, a distinctive heart-specific visceral fat, is closely related to various cardiovascular diseases. The objective of this study was to investigate the correlation between epicardial fat volume (EFV) and subclinical myocardial damage in T2DM patients. This retrospective cross-sectional study included 117 T2DM patients with normal myocardial perfusion by single photon emission computed tomography-computed tomography (SPECT-CT) and normal LVEF by echocardiography. The study was conducted from January 2018 to December 2022. Patient data were collected through electronic medical records including basic patient information, medical history, laboratory tests, and medication data. The EFV was quantified through a non-contrast CT scan. Quantitative indicators of LVSD including phase standard deviation (PSD) and phase histogram bandwidth (PBW) were obtained through phase analysis of the gated rest myocardial perfusion imaging (MPI). Additionally, 83 healthy individuals at the same time were selected to gain the reference threshold of LVSD indicators (13.1° for PSD and 37.6° for PBW). Univariate and multivariable logistic regression models were performed to analyze factors influencing LVSD. A generalized additive model (GAM) was applied to explore the relationship between EFV and LVSD. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of EFV for LVSD. Among all patients, 32 (27.4%) patients had LVSD. Compared with the non-LVSD group, the body mass index (BMI) and EFV were higher in the LVSD group (25.83±2.66 vs. 23.94±3.13 kg/m2; 142.41±44.17 vs. 108.01±38.24 cm3, respectively, both P<0.05). Multivariate regression analysis revealed that EFV was independently associated with LVSD [odds ratio (OR) =1.19; 95% confidence interval (CI): 1.06-1.34; P=0.003]. Age, BMI, incidence of hypertension, and LVSD were increased with tertiles of EFV (all P<0.05). The GAM indicated a linear association between EFV and LVSD. The ROC curve analysis concluded that the area under the curve (AUC) of EFV for predicting subclinical myocardial damage in T2DM patients was 0.732 (95% CI: 0.633-0.831, P<0.001), with the optimal threshold of 122.26 cm3, sensitivity of 71.9%, and specificity of 69.4%. EFV is an independent risk factor for LVSD in T2DM patients with normal LVEF and normal MPI, which could potentially serve as a novel imaging marker and a potential therapeutic target for subclinical myocardial damage.

Metabolic Dysfunction Associated Liver Disease in Patients Undergoing Coronary Computed Tomography Angiography.

In this single-center cross-sectional study on patients undergoing coronary computed tomography angiography (CCTA), we assessed the prognostic significance of metabolic dysfunction associated steatotic liver disease (MASLD), metabolic syndrome (MetS), and CCTA-derived parameters for predicting major adverse cardiovascular events (MACE). Over a mean follow-up of 26.9 months, 2038 patients were analyzed, with 361 (17.7%) experiencing MACE. MASLD was associated with a higher MACE incidence (25.90% vs. 14.71% without MASLD, p < 0.001). Cox regression revealed significant associations between MASLD, coronary calcium score (CCS), number of plaques (NoP), epicardial fat volume (EFV), and MACE, with hazard ratios of 1.843, 1.001, 1.097, and 1.035, respectively (p < 0.001 for all). A composite risk score integrating CCS, NoP, EFV, and MASLD demonstrated superior predictive value for MACE (AUC = 0.948) compared to individual variables (p < 0.0001 for all). In conclusion, MASLD is linked to an elevated risk of MACE, and a comprehensive risk-scoring system incorporating imaging and clinical factors enhances MACE prediction accuracy.

Exploring the Complex Interplay: Fatty Liver Severity, Epicardial Fat Volume, and Coronary Artery Calcification

Background and Objective: Cardiovascular diseases and nonalcoholic fatty liver disease are the most common non-communicable diseases in most developed countries, and due to lifestyle changes, their incidence is increasing day by day. The present study aimed to assess the correlation of fatty liver with epicardial fat volume and coronary artery calcium score. Materials and Methods: This cross-sectional study was conducted on 136 patients referred to Hamadan Farshchian Cardiovascular Hospital for computed tomography (CT) angiography. They were selected using a consecutive sampling method. Using a 128-slice multidetector CT scanner, the coronary artery calcium score based on the Agatston criteria and epicardial fat volume were measured. A liver ultrasound was performed using a GE voluson E6 and a 3-5 MHz depth probe, and the severity of the fatty liver was determined based on the echogenicity of the liver on the ultrasound. Data analysis was conducted using the SPSS software (version 26). Results: The mean age scores of patients were 52.90±12.10 years. Regarding gender, 50.5% and 49.5% of cases were male and female, respectively. In terms of fatty liver grade, 64 (47.1%), 48 (35.3%), 21 (15.4%), and 3 (2.2%) cases had grades zero, I, II, and III, respectively. The mean calcium score was 30.76±35.40, and epicardial fat volume was 86.84±36.56. The severity of fatty liver demonstrated no significant relationship with calcium score and epicardial fat (P&gt;0.05). Conclusion: As evidenced by the obtained results, the severity of fatty liver had no relationship with the amount of coronary epicardial fat and coronary artery calcium.

Correlation of ventricle epicardial fat volume and triglyceride-glucose index in patients with chronic heart failure.

To explore the association of ventricle epicardial fat volume (EFV) calculated by cardiac magnetic resonance (CMR) and the insulin resistance indicator of triglyceride-glucose (TyG) index in patients with chronic HF (CHF), this retrospective cohort study included adult CHF patients with confirmed diagnosis of heart failure from January 2018 to December 2020. All patients underwent 3.0T CMR, and EFV were measured under short-axis cine. Spearman correlation, multivariate linear regression, and restricted cubic spline (RCS) regression were used to analyze their association. There were 516 patients with CHF, of whom 69.8% were male. Median EFV was 57.14mL and mean TyG index was 8.48. Spearman correlation analysis showed that TyG index was significantly correlated with the EFV in CHF patients (r = 0.247, P < 0.001). Further analysis showed that TyG index levels were significantly associated with EFV as both continuous variables (Unstandardized β = 6.556, P < 0.001) and across the increasing quartiles (β = 7.50, 95% CI [1.41, 13.59], P < 0.05). RCS demonstrated there were a positive trend and linear association between EFV and TyG index in CHF patients (P for nonliearity = 0.941). In patients with CHF, the TyG index was positively and linearly associated with the EFV, which supports the metabolic roles of epicardial adipose tissue regarding insulin resistance.

Epicardial fat volume and its association with cardiac arrhythmias in CT coronary angiography.

This retrospective study aimed to investigate the epicardial fat volume in cardiac computed tomography (CT), its relationship with cardiac arrhythmias, and its correlation with the coronary artery disease reporting and data system (CAD-RADS) score. Ninety-six patients who underwent CT coronary angiography (CTCA) were included in this study. Patient data, including demographic information, clinical history, and imaging data were collected retrospectively. Epicardial fat volume was quantified using a standardised algorithm, the CAD-RADS scoring system was applied to assess the extent of coronary artery disease (CAD). Descriptive statistics, correlation analyses, and receiver operating characteristics methods were used. The study found a significant correlation between epicardial fat volume and CAD-RADS score (r2 = 0.31; p < 0.001), indicating the known influence of epicardial fat on CAD risk. Moreover, patients with higher epicardial fat volumes were more likely to experience cardiac tachyarrhythmia (p < 0.001). Receiver operating characteristic analysis established a threshold value of 123 cm3 for epicardial fat volume to predict tachyarrhythmia with 80% sensitivity (AUC = 0.69). In this study a volume of at least 123 cm3 epicardial fat in native coronary calcium scans is associated with cardiac tachyarrhythmia. In these patients, careful selection of suitable imaging protocols is advised.

Low-density lipoprotein- cholesterol and its relation to epicardial fat volume in patients with type II diabetes mellitus

Low-density lipoprotein- cholesterol and its relation to epicardial fat volume in patients with type II diabetes mellitus

Prognostic value of coronary computed tomography angiography parameters, non-alcoholic fatty liver and metabolic syndrome status in symptomatic patients suspected of coronary artery disease

Abstract Background Metabolic syndrome (MetS) is a well-established risk factor for major adverse cardiovascular events (MACE). Previous studies have shown the relationship between MetS, computed tomography derived epicardial fat volume (EFV), non-alcoholic fatty liver disease (NAFLD) status and coronary artery calcium score (CACS) in asymptomatic patients. Objective To assess the prognostic value of coronary computed tomography angiography (CCTA) derived EFV, NAFLD status, CACS and the number of plaques (NoP) in symptomatic patients with and without MetS and to design a new risk score for predicting MACE. Methods We conducted a single-centre, cross-sectional study on 2038 patients with intermediate risk of CAD, which underwent CCTA between March 2019 and May 2022. Data regarding MetS status and other comorbidities were assessed at the moment of the inclusion in the study. CCTA assessment included: CACS, NoP, EFV and NAFLD status. The endpoint was the occurrence of MACE (late revascularization, myocardial infarction, sudden cardiac death). Cox regression was used to assess the relationship between MetS and CCTA derived variables on the occurrence of MACE. Receiver operating characteristic curve analysis was used to determine the prediction value of CCTA derived parameters and of the new risk score. Net reclassification improvement was used to compare the risk score with CACS ability to predict MACE. Results Patients were prospectively followed up during a mean time of 26.9 (standard deviation: 9.5) months. 361 (17.7%) patients developed a MACE (myocardial infarction, n=67; late revascularization, n=282; sudden cardiac death, n=12). More events were seen in MetS+ patients (n=244) versus MetS- patients (n=117) (p&amp;lt;0.001). MetS, age, male gender, CACS, NoP, EFV and NAFLD were all associated with the occurrence of MACE: unadjusted hazard ratios (HR) of: 1.56, 1.25, 1.87, 1.0013, 1.16, 1.053 and 1.67 (p&amp;lt;0.001 for all). However, in the multivariate analysis only the CCTA derived variables showed a significant association with MACE: CCS HR=1.001, NoP HR=1.097, EFV HR=1.035, NAFLD HR=1.843 (p&amp;lt;0.001 for all). Our risk score for predicting MACE included CACS, NoP, EFV and NAFLD. It had an area under the curve (AUC) of 0.948, a sensitivity of 89.7%, a specificity of 92.9% and a negative predicting value of 97.7%. When compared to CCS alone, the risk score correctly reclassified 24 (6.6%) events and 101 (6.2%) non-events, with a net reclassification index of 0.128 (p&amp;lt;0.001). Conclusion MetS is associated with an increased risk for MACE, but not after adjustment for CCS, NoP, EFV, and NAFLD. Adding NoP, EFV and NAFLD to CCS in a risk score further improves the accuracy in predicting MACE, when compared to CCS alone.

Association between index of microcirculatory resistance and patients' characteristics, coronary computed tomography findings, and the sensor location

Abstract Background The index of microcirculatory resistance (IMR) has been widely used for the assessment of microcirculatory function and the detection of the territory with microvascular dysfunction. For measuring coronary physiological indices including IMR, a pressure/temperature sensor-tipped guidewire is recommended to be located distally to the target lesion, however the determinants of IMR including wire location other than the hyperemic microvascular resistance itself are still undetermined. Purpose This study aimed to clarify the determining factors including coronary computed tomography angiography (CCTA) findings, wire position and vessel anatomy and its effect on IMR values. Methods We retrospectively investigated 121 intermediate left anterior descending artery lesions in chronic coronary syndrome patients in our institutional physiological registry (July 2020 to Aug 2022). All patients underwent preprocedural CCTA and coronary physiological assessment with pressure/temperature sensor-tipped guidewire during invasive coronary angiography or percutaneous coronary intervention (PCI). We placed the wire as far distal as practical for the assessment of physiological indices. Under adenosine-induced hyperemia, the wire was pulled manually to the guide catheter and its pullback length was recorded. CCTA assessment included qualitative lesion morphology assessment (spotty calcification, low attenuation plaque, napkin ring sign) and quantitative plaque analysis (remodeling index). Epicardial fat volume is also measured with the proprietary semi-automated software. The predicting factors for IMR was investigated. Result In a total cohort, IMR was 20.40 (14.07-29.92), and the prevalence of IMR&amp;gt;25 was 36 %. On linear regression analysis, patient characteristics including age and gender were not significant predictors for IMR. CCTA-based high risk plaque features (Spotty calcification, low attenuation plaque and napkin ring sign) were also not associated with IMR. In univariable and multivariable linear regression analysis, wire pullback length, remodeling index and epicardial fat volume were significant predictors for IMR (β 1.369 [0.223-2.515, p=0.020, β 6.651 [1.486-11.815], p=0.012, and β 0.055 [0.008-0.103], p=0.023, respectively). Conclusion Wire location (length form the coronary ostium), remodeling index and epicardial fat volume affects IMR values. Caution should be exercised for the interpretation of IMR values in consideration of these factors.

High FABP4, associated with low-voltage areas, increases the epicardial fibrosis and its glucose metabolism

Abstract Background High plasma levels of FABP4 were associated with epicardial fat volume on persistent AF patients. FABP4 can be released by differentiated adipocytes and macrophages, which can be involved in fibrosis. Purpose Our main objective was to study the association between FABP4 and epicardial fibrosis, which can explain low-voltage areas (LVA) and atrial fibrillation (AF) recurrence. Material and methods Peripheral levels of FABP4 and Galectin-3 were analysed on AF patients undergoing pulmonary vein isolation (PVI) (n=299) and signed informed consent. During the intervention, LVA was evaluated by invasive electroanatomic voltage mapping (EAM). Epicardial (EAT) (n=6) and subcutaneous adipose tissue (SAT) (n=5) were obtained from undergoing open heart surgery patients. Stromal cells were isolated by collagenase digestion, cultured and treated with and without FABP4 100 ng/mL and/or galectin-3 30 ng/mL for 24 hours. The proliferation and migration rate were measured by wound healing assay; mitochondrial activity was studied by MTT assay; and glucose and lactate consumption were detected by colorimetric and fluorescence enzymatic assays, respectively. Gene expression levels were assessed by real-time PCR. Results Regression analysis determined that the main independent predictors of LVA were age, left atrial area and FABP4 levels. Preclinical "in vitro" studies have shown that FABP4 100 ng/mL induced fibrosis in epicardial stromal cells (p=0.0039) and subcutaneous stromal cells (p=0.0009), evidenced by wound healing assay and by the increment of associated fibroblast genes (COL1A2, VIM, TGF-β1). Moreover, the high FABP4 concentration modulates the protein levels and metabolic genes expression (CPT1, FASN, ATGL, related to transport, synthesis and degradation of fatty acids, respectively) on EAT stromal cells. Glucose metabolism without lactate production was also incremented after FABP4 treatment (p&amp;lt;0.0001). Even, on SAT cells, released lactate was reduced after FABP4 treatment (p=0.0218). Conclusions Plasma FABP4 was a predictor of LVA. Our results suggest that this association might be explained by the fibrotic and metabolic role of FABP4 in epicardial cells. Future studies will shed light on the benefits on atrial remodelling with FABP4 modulators.Figure 1Figure 2

Peripheral and local inflammatory markers associated with epicardial fat volume in patients underwent open heart surgery

Abstract Introduction Epicardial fat (EF) is a source of inflammation, and it is associated with cardiovascular diseases. However, the correlation between EF volume (EFV) and local and peripheral biomarkers as well as adipogenesis behavior were not studied yet. Our objective was to a) Find the peripheral and local markers related to EFV independent of age and BMI. b) Study the relationship between the adipogenesis capacity and the EFV in each patient. Materials and Methods We included 33 patients underwent open heart surgery with preoperative cardiac CT imaging. Blood samples of 24 patients were obtained, neutrophils were isolated using polymorphprep and 16 activity markers were analyzed. Twelve biomarkers in plasma associated with metabolism and inflammation were analyzed. The epicardial adipose tissue biopsies were obtained during the surgery. The fat pads were homogenized and RNA was isolated and retrotranscripted to cDNA. Then 17 markers associated with adipogenesis and inflammation were analyzed by real time PCR. Stromal cells from EF of 21 patients were isolated after collagenase activity and cultured for 14 days and then induced to adipogenesis for the next 14 days. Multimarkers on plasma, peripheral neutrophils, EF and primary cultures were analyzed by multiplex assay and real time PCR, respectively. EFV was measured from CT, percentage of EFV in total heart volume was calculated. The association between FV and biomarkers were evaluated with independent sample t-test, linear regression analysis and correlation analysis. Results The main clinical characteristics of studied patients were (69 ± 9 years old, 30 ± 4 kg/m², 76% HT, 67% DLP, 33% CAD, 27% HF, 30% AF, 30% T2DM). EFV (148±55 cm³) was more correlated with age (r=0.4, p=0.023), but not with BMI. Percentage of EFV in total heart volume (12.9±4.9%) was positively correlated with lymphocytes and monocytes markers, CD3G and CXCR2 levels (r=0.5, p=0.008; r=0.49, p=0.028 respectively), and inversely with FABP4 (r=0.46, p=0.043) in EF. Circulating inflammatory markers, plasma C5a and MPO on neutrophils were associated with a greater amount of EFV (r=0.7, p=0.001 for C5a and r=0.75, p=0.001 for MPO) and percentage of EFV in total heart volume (r=0.63, p=0.003 for C5a and r=0.84, p&amp;lt;0.000 for MPO). Neutrophils markers, NGAL (r=0.49, p=0.048), LF (r=0.52, p=0.034), DEFA3 (r=0.57, p=0.023) were also correlated with percentage of EFV to total heart volume. Lineal regression determined that among local markers CD3G was the best EF predictor (r=0.4, p=0.008); regarding peripheral markers, the C5a expression levels on neutrophils was the best EF predictor (r=0.61, p=0.002). There were no association between adipogenesis ability and EFV among studied patients. Conclusion EFV from patients undergoing open heart surgery were associated with local and peripheral inflammatory markers. It might contribute to cardiovascular disease progression. Long term follow-up is needed to clarify this process.

Epicardial fat volume, an independent risk factor for major adverse cardiovascular events, had an incremental prognostic value to myocardial perfusion imaging in Chinese populations with suspected or known coronary artery disease with a normal left ventricular ejection fraction.

Most coronary artery disease (CAD) patients with a normal left ventricular ejection fraction (LVEF) experience a poor prognosis. Single-photon emission computerized tomography (SPECT)-myocardial perfusion imaging (MPI), a routine examination, is useful in assessing risk and predicting major adverse cardiovascular events (MACEs) in populations with suspected or known CAD. SPECT/CT is a "one-stop shop" examination, which, through non-contrast CT, can produce attenuation correction for MPI and obtain information on coronary artery calcium (CAC) and epicardial fat volume (EFV) simultaneously. This study aims to investigate the predictive and incremental value of EFV to MPI for MACE in Chinese populations with suspected or known CAD with a normal LVEF. We retrospectively studied 290 suspected or known CAD inpatients with a normal LVEF who underwent SPECT/CT between February 2014 and December 2017. Abnormal MPI was defined as a summed stress score ≥4 or summed difference score ≥2. EFV and CAC were calculated using non-contrast CT. The end date of follow-ups was in February 2022. The follow-up information was obtained from the clinical case notes of the patients or reviews of telephone calls. MACE was defined as cardiac death, late coronary revascularization ≥3 months after MPI, non-fatal myocardial infarction, angina-related rehospitalization, heart failure, and stroke. During the 76-month follow-up, the event rate was 32.0% (93/290). Univariate and multivariate Cox regression analyses concluded that high EFV (>108.3 cm3) [hazard ratio (HR): 3.3, 95% CI: 2.1-5.2, P < 0.000] and abnormal MPI (HR: 1.8, 95% CI: 1.1-2.8, P = 0.010) were independent risk factors for MACE. The event-free survival of patients with high EFV was significantly lower than that of the low EFV group (log-rank test P < 0.001). In the subgroup with normal MPI, high EFV was associated with reduced event-free survival (log-rank P < 0.01), with a higher annualized event rate (8.3% vs. 1.9%). Adding high EFV to MPI could predict MACEs more effectively, with a higher concordance index (0.56-0.69, P < 0.01), higher global chi square (7.2-41.4, P < 0.01), positive integrated discrimination improvement (0.10, P < 0.01), and net reclassification index (0.37, P < 0.01). In Chinese populations with suspected or known CAD with normal LVEF, high EFV was an independent risk factor for MACE after adjusting for traditional risk factors, CAC and MPI. In subgroups with normal MPI, EFV could also improve risk stratification. Adding EFV to MPI had an incremental value for predicting MACE.

Epicardial Fat Volume as a Good Predictor for Multivessel Coronary Artery Disease.

Epicardial adipose tissue may have an important role in the pathogenesis of coronary artery disease (CAD). We aimed to study the association between epicardial fat volume (EFV) and presence of obstructive as well as multivessel CAD. A total of 87 adult subjects with suspected CAD who underwent both quantified by multidetector computerized tomography (MDCT) and Invasive Coronary Angiography (ICA) were enrolled in this observational study. EVF was measured by MDCT by calculating the sum of cross- sectional areas of fat multiplied by slice thickness. EFV measurement and its association with the presence of obstructive CAD (defined as coronary artery stenosis > 70%) was evaluated. Overall, 89.6% patients had obstructive CAD with higher EFV as compared to 10.3% patients with non-obstructive CAD (57 ± 20.14 cm3 vs. 44 ± 7.4 cm3; P < 0.001). Furthermore, EFV was significantly increased in group II as compared with group I (74 ± 24.3 ml vs. 53 ± 16.2 ml; P < 0.003). On the hand, the coronary calcium score (CAC) was insignificantly increased in group II as compared with group I (486.1 vs. 211.2; P = 0.10). Multivariate analysis revealed that, EFV might be an independent risk factor for not only the presence of obstructive CAD (odds ratio [OR], 1.062; 95% CI 1.018- 1.108; P < 0.005) but also in predicting multivessel disease affection. Our results demonstrated that, EFV was significantly increased not only with obstructive CAD, independent of other traditional risk factors and CAC score, but also it can be considered a good predictor of multivessel disease occurrence.

Epicardial fat in patients with metabolic syndrome: A systematic review and meta-analysis

PurposeAbnormally increased epicardial fat appears to be associated with an additional risk of major adverse cardiovascular events (MACEs) in the context of metabolic syndrome (MetS). However, evidence on the relationship between epicardial fat volumes (EFVs), epicardial fat thickness (EFT) and MetS remains inconsistent. MethodsSpecific searches of electronic databases from 1 January 2000 to 31 October 2022 were independently performed by two researchers. In this study, two quantification measures of epicardial fat were included: comparison of total computed tomography–based EFVs and EFT between two groups (individuals with and without MetS), estimating standardized mean difference (SMD) with corresponding 95 % confidence intervals (CIs) through a random-effects model analysis. The heterogeneity in the included studies was explored by meta-regression and subgroup analyses. ResultsThe EFVs were significantly increased in MetS subjects compared with non-MetS subjects (SMD: 1.07, 95 % CI: 0.69–1.45, p < 0.001), and the EFT was also significantly larger in MetS patients than in the Non-MetS (SMD: 1.12, 95 % CI: 0.84–1.41, p < 0.001). We compared the Caucasian and American subgroups with the Asian and African subgroups, and the EFT was greater in the former subgroups (SMD: 1.32, 95 % CI: 0.44–2.20, p < 0.001). When comparing the EFT among the age subgroups, there was a significant SMD between adolescents and adults or elderly individuals (SMD: 1.21, 95 % CI: 0.84–1.52, p < 0.001). ConclusionsMetS patients tend to present greater EFT near the right ventricular free wall and greater total EFVs. Increased epicardial fat, an imaging biomarker, independently affects the onset of MetS.