Fei-Shih Yang

Pericardial and thoracic peri-aortic adipose tissues contribute to systemic inflammation and calcified coronary atherosclerosis independent of body fat composition, anthropometric measures and traditional cardiovascular risks

BACKGROUNDnCoronary atherosclerosis has traditionally been proposed to be associated with several cardiovascular risk factors and anthropometric measures. However, clinical data regarding the independent value of visceral adipose tissue in addition to such traditional predictors remains obscure.nnnMATERIALS AND METHODSnWe subsequently studied 719 subjects (age: 48.1±8.3 years, 25% females) who underwent multidetector computed tomography (MDCT) for coronary calcium score (CCS) quantification. Baseline demographic data and anthropometric measures were taken with simultaneous body fat composition estimated. Visceral adipose tissue of pericardial and thoracic peri-aortic fat was quantified by MDCT using TeraRecon Aquarius workstation (San Mateo, CA). Traditional cardiovascular risk stratification was calculated by metabolic (NCEP ATP III) and Framingham (FRS) scores and high-sensitivity CRP (Hs-CRP) was taken to represent systemic inflammation. The independent value of visceral adipose tissue to systemic inflammation and CCS was assessed by utilizing multivariable regression analysis.nnnRESULTSnOf all subjects enrolled in this study, the mean values for pericardial and peri-aortic adipose tissue were 74.23±27.51 and 7.23±3.69ml, respectively. Higher visceral fat quartile groups were associated with graded increase of risks for cardiovascular diseases. Both adipose burdens strongly correlated with anthropometric measures including waist circumference, body weight and body mass index (all p<0.001). In addition, both visceral amount correlates well with ATP and FRS scores, all lipid profiles and systemic inflammation marker in terms of Hs-CRP (all p<0.001). After adjustment for baseline variables, both visceral fat were independently related to Hs-CRP levels (all p<0.05), but only pericardial fat exerted independent role in coronary calcium deposit.nnnCONCLUSIONnBoth visceral adipose tissues strongly correlated with systemic inflammation beyond traditional cardiovascular risks and anthropometric measures, though only pericardial fat exerted independent role in coronary calcium deposit. Our data suggested that visceral adipose tissue may thus contribute to systemic inflammation and play an independent role in the pathogenesis of atherosclerosis.

Epicardial adipose tissue relating to anthropometrics, metabolic derangements and fatty liver disease independently contributes to serum high-sensitivity C-reactive protein beyond body fat composition: a study validated with computed tomography.

BACKGROUNDnEpicardial adipose tissue (EAT) measured by echocardiography has been proposed to be associated with metabolic syndrome and increased cardiovascular risks. However, its independent association with fatty liver disease and systemic inflammation beyond clinical variables and body fat remains less well known.nnnMETHODSnThe relationships between EAT and various factors of metabolic derangement were retrospectively examined in consecutive 359 asymptomatic subjects (mean age, 51.6 years; 31% women) who participated in a cardiovascular health survey. Echocardiography-derived regional EAT thickness from parasternal long-axis and short-axis views was quantified. A subset of data from 178 randomly chosen participants were validated using 16-slice multidetector computed tomography. Body fat composition was evaluated using bioelectrical impedance from foot-to-foot measurements.nnnRESULTSnIncreased EAT was associated with increased waist circumference, body weight, and body mass index (all P values for trend = .005). Graded increases in serum fasting glucose, insulin resistance, and alanine transaminase levels were observed across higher EAT tertiles as well as a graded decrease of high-density lipoprotein (all P values for trend <.05). The areas under the receiver operating characteristic curves for identifying metabolic syndrome and fatty liver disease were 0.8 and 0.77, with odds ratio estimated at 3.65 and 2.63, respectively. In a multivariate model, EAT remained independently associated with higher high-sensitivity C-reactive protein and fatty liver disease.nnnCONCLUSIONSnThese data suggested that echocardiography-based epicardial fat measurement can be clinically feasible and was related to several metabolic abnormalities and independently associated fatty liver disease. In addition, EAT amount may contribute to systemic inflammation beyond traditional cardiovascular risks and body fat composition.

The normal limits, subclinical significance, related metabolic derangements and distinct biological effects of body site-specific adiposity in relatively healthy population.

Background The accumulation of visceral adipose tissue that occurs with normal aging is associated with increased cardiovascular risks. However, the clinical significance, biological effects, and related cardiometabolic derangements of body-site specific adiposity in a relatively healthy population have not been well characterized. Materials and Methods In this cross-sectional study, we consecutively enrolled 608 asymptomatic subjects (mean age: 47.3 years, 27% female) from 2050 subjects undergoing an annual health survey in Taiwan. We measured pericardial (PCF) and thoracic peri-aortic (TAT) adipose tissue volumes by 16-slice multi-detector computed tomography (MDCT) (Aquarius 3D Workstation, TeraRecon, San Mateo, CA, USA) and related these to clinical characteristics, body fat composition (Tanita 305 Corporation, Tokyo, Japan), coronary calcium score (CCS), serum insulin, high-sensitivity C-reactive protein (Hs-CRP) level and circulating leukocytes count. Metabolic risk was scored by Adult Treatment Panel III guidelines. Results TAT, PCF, and total body fat composition all increased with aging and higher metabolic scores (all p<0.05). Only TAT, however, was associated with higher circulating leukocyte counts (ß-coef.:0.24, p<0.05), serum insulin (ß-coef.:0.17, p<0.05) and high sensitivity C-reactive protein (ß-coef.:0.24, p<0.05). These relationships persisted after adjustment in multivariable models (all p<0.05). A TAT volume of 8.29 ml yielded the largest area under the receiver operating characteristic curve (AUROC: 0.79, 95%CI: 0.74–0.83) to identify metabolic syndrome. TAT but not PCF correlated with higher coronary calcium score after adjustment for clinical variables (all p<0.05). Conclusion In our study, we observe that age-related body-site specific accumulation of adipose tissue may have distinct biological effects. Compared to other adiposity measures, peri-aortic adiposity is more tightly associated with cardiometabolic risk profiles and subclinical atherosclerosis in a relatively healthy population.

High pericardial and peri-aortic adipose tissue burden in pre-diabetic and diabetic subjects

BackgroundCentral obesity in relation to insulin resistance is strongly linked to the development of type 2 diabetes. However, data regarding the association between pericardial and peri-aortic adiposity, a potential estimate of visceral adipose tissue burden, and pre-diabetes status remains unclear.The aim of this study was to examine whether the degree of pericardial and thoracic peri-aortic adipose tissue, when quantified by multi-detector computed tomography (MDCT), differs significantly in a normal, pre-diabetic, and overtly diabetic population.MethodsWe studied 562 consecutive subjects including 357 healthy, 155 pre-diabetic, and 50 diabetic patients selected from participants who underwent annual health surveys in Taiwan. Pre-diabetes status was defined by impaired fasting glucose or impaired glucose intolerance according to American Diabetes Association guidelines. Pericardial (PCF) and thoracic peri-aortic (TAT) adipose tissue burden was assessed using a non-contrast 16-slice multi-detector computed tomography (MDCT) dataset with off-line measurement (Aquarius 3D Workstation, TeraRecon, San Mateo, CA, USA). Body fat composition, serum high-sensitivity C-reactive protein (hs-CRP) level and insulin resistance (HOMA-IR) were also assessed.ResultsPatients with diabetes and pre-diabetes had greater volume of PCF (89u2009±u200924.6, 85.3u2009±u200928.7 & 67.6u2009±u200926.7 ml, pu2009<u20090.001) as well as larger TAT (9.6u2009±u20093.1 ml vs 8.8u2009±u20094.2 & 6.6u2009±u20093.5 ml, respectively, pu2009<u20090.001) when compared to the normal group, although there were no significant differences in adiposity between the diabetic and pre-diabetic groups. For those without established diabetes in our study, increasing TAT burden, but not PCF, appear to correlate with insulin resistance (HOMA-IR) and hs-CRP in the multivariable models.ConclusionsPre-diabetic and diabetic subjects, compared to normoglycemia, were associated with significantly higher pericardial and peri-aortic adipose tissue burden. In addition, visceral fat accumulation adjacent to the thoracic aorta seemed to exert a significant impact on insulin resistance and systemic inflammation.

Qualitative and semi-quantitative evaluation of myocardium perfusion with 3 T stress cardiac MRI

Background3xa0T MRI has been adopted by some centers as the primary choice for assessment of myocardial perfusion over conventional 1.5xa0T MRI. However, there is no data published on the potential additional value of incorporating semi-quantitative data from 3xa0T MRI. This study sought to determine the performance of qualitative 3xa0T stress magnetic resonance myocardial perfusion imaging (3xa0T-MRMPI) and the potential incremental benefit of using a semi-quantitative perfusion technique in patients with suspected coronary artery disease (CAD).MethodsFifty eight patients (41 men; mean age: 59xa0years) referred for elective diagnostic angiography underwent stress 3xa0T MRMPI with a 32-channel cardiac receiver coil. The MR protocol included gadolinium-enhanced stress first-pass perfusion (0.56xa0mg/kg, dipyridamole), rest perfusion, and delayed enhancement (DE). Visual analysis was performed in two steps. Ischemia was defined as a territory with perfusion defect at stress study but no DE or a territory with DE but additional peri-infarcted perfusion defect at stress study. Semi-quantitative analysis was calculated by using the upslope of the signal intensity-time curve during the first pass of contrast medium during dipyridamole stress and at rest. ROC analysis was used to determine the MPRI threshold that maximized sensitivity. Quantitative coronary angiography served as the reference standard with significant stenosis defined as >70xa0% diameter stenosis. Diagnostic performance was determined on a per-patient and per-vessel basis.ResultsQualitative assessment had an overall sensitivity and specificity for detecting significant stenoses of 77xa0% and 80xa0%, respectively. By adding MPRI analysis, in cases with negative qualitative assessment, the overall sensitivity increased to 83xa0%. The impact of MPRI differed depending on the territory; with the sensitivity for detection of left circumflex (LCx) stenosis improving the most after semi-quantification analysis, (66xa0% versus 83xa0%).ConclusionsPure qualitative assessment of 3xa0T MRI had acceptable performance in detecting severe CAD. There is no overall benefit of incorporating semi-quantitative data; however a higher sensitivity can be obtained by adding MPRI, especially in the detection of LCx lesions.

The association among peri-aortic root adipose tissue, metabolic derangements and burden of atherosclerosis in asymptomatic population

AIMnTo describe the relationship between a novel measurement of peri-arotic root fat and ultrasound measures of carotid artery remodeling.nnnMATERIALS AND METHODSnWe studied 1492 consecutive subjects (mean age: 51.04 ± 8.97 years, 27% females) who underwent an annual cardiovascular risk survey in Taiwan. Peri-aortic root fat (PARF) was assessed by cardiac CT using three-dimensional (3D) volume assessment. Carotid artery morphology and remodeling were assessed by ultrasound. We explored the relationships between PARF volumes, cardiometabolic risk profiles and carotid morphology and remodeling.nnnRESULTSnMean PARF volume in current study was 20.8 ± 10.6 ml. PARF was positively correlated with measures of general adiposity, systemic inflammation, and several traditional cardiometabolic risk profiles (all p < 0.001) and successfully predicted metabolic syndrome (MetS) (AUROC: 0.75, 95%, confidence interval: 0.72-0.77). Higher PARF was independently associated with increased carotid artery intima-media thickness (IMT) (β-coef.: 0.08) and diameter (β-coef.: 0.08, both p < 0.05) after accounting for age, sex, BMI and other cardiovascular risk factors. The addition of PARF beyond metabolic syndrome components significantly provided incremental prediction value for abnormal IMT (ΔAUROC: 0.053, p = 0.0021).nnnCONCLUSIONnPeri-aortic root fat is associated with carotid IMT, even after adjustment for cardiometabolic risks, age and coronary atherosclerosis. Further research studies are warranted to identify the mediators of downstream pathophysiologic effects on carotid arteries by PARF and understand the mechanisms related to this correlation.

Excessive interatrial adiposity is associated with left atrial remodeling, augmented contractile performance in asymptomatic population

Abstract Purpose Pericardial adipose tissue had been shown to exert local effects on adjacent cardiac structures. Data regarding the mechanistic link between such measures and left atrial (LA) structural/functional remodeling, a clinical hallmark of early stage heart failure (HF) and atrial fibrillation (AF) incidence, in asymptomatic population remain largely unexplored. Methods This retrospective analysis includes 356 subjects free from significant valvular disorders, atrial fibrillation, or clinical HF. Regional adipose tissue including pericardial and periaortic fat volumes, interatrial septal (IAS), and left atrioventricular groove (AVG) fat thickness were all measured by multidetector computed tomography (MDCT) (Aquarius 3D Workstation, TeraRecon, San Mateo, CA, USA). We measured LA volumes, booster performance, reservoir capacity as well as conduit function, and analyzed their association with adiposity measures. Results All four adiposity measures were positively associated with greater LA volumes (all P < 0.05), while IAS and AVG fat were also related to larger LA kinetic energy and worse reservoir capacity (both P < 0.01). In multivariate models, IAS fat thickness remained independently associated with larger LA volumes, increased LA kinetic energy and ejection force (β-coef: 0.17 & 0.15, both P < 0.05), and impaired LA reservoir and conduit function (β-coef: −0.20 & −0.12, both P < 0.05) after adjusting for clinical variables. Conclusion Accumulated visceral adiposity, especially interatrial fat depots, was associated with certain LA structural/functional remodeling characterized by impaired LA reservoir and conduit function though augmented kinetic energy and ejection performance. Our data suggested that interatrial fat burden may be associated with certain detrimental LA functions with compensatory LA adaptation in an asymptomatic population.

The Associations between Various Ectopic Visceral Adiposity and Body Surface Electrocardiographic Alterations: Potential Differences between Local and Remote Systemic Effects

Background The associations between pericardial adiposity and altered atrial conduction had been demonstrated. However, data comparing differential effects of various body sites visceral adiposity on atrial and ventricular electrocardiographic alterations remains largely unknown. Methods and Results We assessed both peri-cardial fat (PCF) and peri-aortic visceral adiposity (TAT) using dedicated computed tomography (CT) software (Aquarius 3D Workstation, TeraRecon, San Mateo, CA, USA), with anthropometrics including body mass index (BMI) and biochemical data obtained. We further related PCF and TAT data to standardized 12-leads electrocardiogram (ECG), including P and QRS wave morphologies. Among 3,087 study subjects (mean age, 49.6 years; 28% women), we observed a linear association among greater visceral adiposity burden, leftward deviation of P and QRS axes, longer PR interval and widened QRS duration (all p<0.001). These associations became attenuated after accounting for BMI and baseline clinical co-variates, with greater PCF remained independently associated with prolonged QRS duration (β = 0.91 [95% CI: 0.52, 1.31] per 1-SD increase in PCF, p<0.001). Finally, both PCF and TAT showed incremental value in identifying abnormally high PR interval (>200ms, likelihood-ratio: 33.17 to 41.4 & 39.03 for PCF and TAT) and widened QRS duration (>100ms, likelihood-ratio: 55.67 to 65.4 & 61.94 for PCF and TAT, all X2 p<0.05) when superimposed on age and BMI. Conclusion We show in our data greater visceral fat burden may have differential associations on several body surface electrocardiographic parameters. Compared to remote adiposity, those surrounding the heart tissue demonstrated greater influences on altered cardiac activation or conduction, indicating a possible local biological effect.

Quantification of peri-aortic root fat from non-contrast ECG-gated cardiac computed tomography

In this data, we present the details of the cross-sectional study from Mackay Memorial Hospital, Taipei, Taiwan that examined the relationship between three-dimensional (3D) peri-aortic root fat (PARF) volumes, cardiometabolic risk profiles, carotid artery morphology and remodeling. Our sample is composed of a total 1492 adults who underwent an annual cardiovascular risk survey in Taiwan. PARF was measured using images of gated non-contrast cardiac computed tomography (CT) and a dedicated workstation (Aquarius 3D Workstation, TeraRecon, San Mateo, CA, USA). The stratified analyses were performed in order to assess the association between carotid morphology, remodeling and PARF by tertile. For further analyses and discussion, please see “The Association among Peri-Aortic Root Adipose Tissue, Metabolic derangements and Burden of Atherosclerosis in Asymptomatic Population” by Yun et al. (2015) [1].

Additional file 1: Figure S1. of The association among MDCT-derived three-dimensional visceral adiposities on cardiac diastology and dyssynchrony in asymptomatic population

Pulsed-wave tissue Doppler measurement of intra-ventricular dyssynchrony. Upper panel: lateral wall TDI waveform. Lower panel: medial wall TDI waveform. The time intervals between QRS onset and peak of S’/E’ were measured respectively. Systolic dyssynchrony was presented as the absolute time-to-peak difference of S’ between lateral and medial segments (T1-T3). Diastolic dyssynchrony was presented as the absolute time-to-peak difference of E’ (T2-T4). Abbreviations: Slu2009=u2009lateral systolic myocardial velocity, Elu2009=u2009lateral early-diastolic myocardial velocity, Smu2009=u2009medial systolic myocardial velocity, Emu2009=u2009medial early-diastolic myocardial velocity. (TIFF 799xa0kb)