Increased echocardiographic epicardial fat thickness is related to impaired diurnal blood pressure profiles

Association between epicardial adipose tissue and blood pressure: A systematic review and meta-analysis

AIMS

Epicardial adipose tissue has been reported to be associated with the development of cardiometabolic disease. Whether this is true for hypertension and non-dipper blood pressure remains controversial. Here, we conducted a systemic review and meta-analysis to evaluate the association between EAT and blood pressure.

DATA SYNTHESIS

Pubmed, Embase, and Web of Science were searched for relevant papers. Studies reported on the difference of EAT thickness between hypertensive and normotensive patients, or those recorded odds ratio (OR) between EAT and hypertension were included. The standard mean difference (SMD) and ORs were extracted and pooled using a random-effects model respectively. We further assessed the effect of EAT on circadian rhythm of blood pressure by combining multiple-adjusted ORs for non-dipper blood pressure. Seven studies with an overall sample of 1089 patients reported the mean difference of EAT thickness between hypertensive and normotensive patients, and the hypertensive patients had higher EAT (SMD = 1.07; 95% CI: 0.66-1.48; I2 = 89.2%) compared with controls. However, the pooled association between EAT and hypertension from two studies was not significant (OR = 1.65, 95%CI 0.62-4.68; I2 = 87.5%). The summary risk effect of EAT on non-dipper blood pressure from six studies comprising1208 patients showed that each 1 mm increment of EAT was associated with a 2.55-fold risk of non-dipper blood pressure.

CONCLUSION

Hypertensive patients tend to present higher EAT thickness near the right ventricular wall and increased EAT thickness might be associated with high risk of non-dipper blood pressure. Future researches are warranted to determine the causal link between EAT and hypertension and the underlying mechanism.

Increased epicardial adipose tissue thickness is associated with microalbuminuria in hypertensive patients with left ventricular hypertrophy

OBJECTIVE

Epicardial adipose tissue (EAT) is a cardiometabolic risk factor, and its possible relationship with hypertension has been previously reported. Microalbuminuria (MA) is associated with target-organ damage, especially in patients with hypertension with left ventricular hypertrophy (LVH) and suggest endothelial dysfunction. This study aimed to investigate the relationship between echocardiographic EAT thickness and presence of MA in patients with hypertension.

METHODS

A total of 297 newly diagnosed hypertension patients who applied to the outpatient clinic were enrolled consecutively in this study. Patients were divided into two groups regarding the presence of LVH in echocardiography. An age and gender matched control group was set including 156 healthy patients without HT. All subjects underwent transthoracic echocardiography for the measurement of EAT thickness. Spot urine samples were collected for the assessment of MA.

RESULTS

In hypertensive patients with LVH, the EAT thicknesses (6.6 ± 1.8 vs 5.3 ± 1.5 vs 5.1 ± 1.3, p < .001; respectively) and prevalence of MA (41.2 vs 20.1 vs 3.2%; p < .001 respectively) were significantly higher than the other two groups. In hypertensive patiens without LVH, no relationship was found between the presence of MA and EAT thickness. In multivariate regression analyses, EAT thickness (OR: 3.141, 95%CI: 2.425-6.123, p < .001) and left ventricular mass index (OR: 1.339, 95%CI: 1.145-2.143, p = .003) were determined as independent predictors for MA development in hypertensive patients with LVH.

CONCLUSION

Measurement of EAT thickness may help to identify high-risk hypertensive patients for target-organ damage especially among patients with LVH.

Homocysteine, visceral adiposity-related novel cardiometabolic risk factors, and exaggerated blood pressure response to the exercise treadmill test

OBJECTIVE

Exaggerated blood pressure response to exercise is a risk factor for the development of future hypertension. In this study, we aimed to investigate the association between homocysteine, epicardial fat thickness, nonalcoholic hepatic steatosis, and exaggerated blood pressure response to exercise.

PARTICIPANTS AND METHODS

We included 44 normotensive and 40 patients with exaggerated blood pressure response to exercise who have normal resting blood pressure and without a previous diagnosis of hypertension. All patients underwent treadmill exercise test and clinical, ultrasonographic, and echocardiographic evaluation. Exaggerated blood pressure response to exercise is defined as peak exercise systolic blood pressure of at least 210 mmHg in men and at least 190 mmHg in women. Homocysteine and other biochemical parameters were determined with standardized automated laboratory tests.

RESULTS

Mean age of all participants is 47.9±8.5 years, and 36 of 84 participants were female. The frequency of diabetes mellitus in both groups was similar (P=0.250). Homeostasis model assessment index-insulin resistance had a statistically insignificant trend to be higher in a patient with exercise hypertension (P=0.058). The nonalcoholic fatty liver was more frequent in patients with exercise hypertension (13.6 vs. 47.5%, P=0.002). Epicardial fat thickness was increased in patients with exercise hypertension (5.5±1.5 vs. 7.3±1.1 mm; P=0.001). However, homocysteine levels did not significantly differ between normotensive and exercise hypertensive patients [12.3 μmol/l (5.7-16.9 μmol/l) vs. 13 μmol/l (5.9-28.3 μmol/l); P=0.883].

CONCLUSION

In our study, homocysteine levels were not associated with exaggerated blood pressure response to exercise; however, fatty liver and epicardial fat thickness as visceral adiposity-related cardiometabolic risk factors were significantly related with exaggerated blood pressure response to exercise in patients without a previous diagnosis of hypertension.

Maximal pericoronary adipose tissue thickness is associated with hypertension in nonobese patients with acute or chronic illness

BACKGROUND/AIMS

Recent studies have shown an association of epicardial fat thickness with diabetes and hypertension (HTN) in asymptomatic populations. However, there is lack of information as to whether there is similar association between pericoronary adipose tissue (PAT) and HTN in the patients who have acute or chronic illness.

METHODS

This study included 214 nonobese patients hospitalized with acute or chronic noncardiogenic illness. PAT thicknesses were measured from fat tissues surrounding left and right coronary arteries in enhanced, chest computed tomography scans, yielding the maximal PAT value from left and right coronary arteries was used for analysis. Baseline data from hypertensive (n = 81) and normotensive (n = 133) patients were collected and compared.

RESULTS

PAT is positively correlated with age (r = 0.377, p <0.001), body mass index (BMI; r = 0.305, p < 0.001), systolic blood pressure (r = 0.216, p = 0.001), and total cholesterol (r = 0.200, p = 0.006). The hypertensive group was older (69.58 ± 11.69 years vs. 60.29 ± 14.98 years), and had higher PAT content (16.30 ± 5.37 mm vs. 13.06 ± 5.58 mm) and BMI (23.14 ± 3.32 kg/m² vs. 20.96 ± 3.28 kg/m) than the normotensive group (all p < 0.001). Multivariate analysis showed that age (odds ratio [OR], 2.193; p = 0.016), PAT thickness (OR, 1.065; p = 0.041), and BMI (25 ≤ BMI < 30 kg/m² ; OR, 6.077; p = 0.001) were independent risk factors for HTN.

CONCLUSIONS

In nonobese patients with noncardiogenic acute or chronic illness, PAT thickness is independently correlated with HTN, age, and BMI.

Determination of UCP1 expression in subcutaneous and perirenal adipose tissues of patients with hypertension

The objective of this study is to determine the property of human perirenal adipose tissue (PAT) and assess the adipose property of PAT in hypertension. Ninety-four patients, including 64 normotensive patients (T-NP) and 30 hypertensive patients (HP), who underwent renal surgery were included. Expression analysis was performed using quantitative real-time polymerase chain reaction, Western blot, and immunohistochemistry in PAT and back subcutaneous adipose tissue (bSAT) depots. Compared with bSAT, PAT adipocytes were smaller, and the expressions of uncoupling protein-1 (UCP1) mRNA and protein were markedly higher, while the mRNA expressions of markers for classic beige and white adipocytes were lower in PAT. Immunohistochemistry analysis showed more multilocular UCP1-positive adipocytes in PAT than in bSAT. UCP1 expressions were lower in PAT in HP than in the T-NP or age- and body mass index-matched NP groups. Bigger unilocular adipocytes with less UCP1 staining in PAT were detected in HP than in NP group, although no such difference was observed in bSAT. PAT acts as a brown-like fat. UCP1 expression of PAT was lower in HP than in normotensive patients. UCP1 expression of PAT may serve as a protective indicator for hypertension.

New inflammatory markers for prediction of non-dipper blood pressure pattern in patients with essential hypertension: Serum YKL-40/Chitinase 3-like protein 1 levels and echocardiographic epicardial adipose tissue thickness

The aim of the present study was to investigate whether YKL-40 levels and epicardial adipose tissue (EAT) thickness were associated with non-dipping pattern in essential hypertension (HT). Age- and sex-matched 40 dipper hypertensive patients and 40 non-dipper hypertensive patients were included in the study. Non-dippers had significantly increased EAT thickness and higher YKL-40 and high-sensitivity C-reactive protein levels than dippers. Multivariate logistic regression analysis showed that the EAT thickness and serum levels of YKL-40 and high-sensitivity C-reactive protein were independent predictors of non-dipping pattern in essential HT. In essential HT, presence of non-dipping pattern is associated with increased inflammatory response.

Impact of Gender on the Association of Epicardial Fat Thickness, Obesity, and Circadian Blood Pressure Pattern in Hypertensive Patients

This study aimed to investigate the effects of gender on the association between epicardial fat thickness (EFT) and circadian blood pressure (BP) changes in patients with recently diagnosed essential hypertension (EH). A total of 441 patients with EH (male/female: 236/205, mean age: 50.7 ± 13.8) and 83 control patients underwent 24-hour ambulatory BP monitoring and echocardiography. Obese EH patients had higher circadian BP profile with BP variability, wall thickness, and left ventricular mass than nonobese EH patients and controls (all p's <0.05) without gender differences. EFT was higher in female than in male patients (7.0 ± 2.5 versus 5.9 ± 2.2 mm, p < 0.001) and higher in the obese female EH group (7.5 ± 2.6 mm) than in the control (6.4 ± 2.8 mm) or nonobese EH group (6.7 ± 2.8 mm) among women, whereas EFT did not vary among males (5.9 ± 1.9 versus 6.0 ± 2.7 versus 5.9 ± 2.4 mm, p = 0.937). Multivariate logistic regression analysis demonstrated that the 24-hour mean BP variability was associated with SBP (p = 0.018) and EFT (p = 0.016) in female patients, but not in male patients. The relationships among circadian BP variability, obesity, and EFT were affected by gender in different manners. EFT may be a more valuable parameter in the evaluation of BP severity and obesity in women than in men.

Echocardiographic epicardial fat thickness and neutrophil to lymphocyte ratio are novel inflammatory predictors of cerebral ischemic stroke

BACKGROUND

The role of epicardial fat thickness (EFT) in ischemic stroke (IS) has not been previously investigated. The aim of the present study was to evaluate EFT and neutrophil/lymphocyte ratio (NLR) among patients with IS and to examine the relationship between these inflammatory markers and the incidence of IS.

METHODS

The cross-sectional design includes 38 patients with IS and 47 age- and sex-matched healthy controls. Echocardiographic measurement of EFT was conducted according to previously published methods. An automated hematology analyzer was used to generate total and differential leukocyte counts from patient blood samples.

RESULTS

Mean EFT was 4.86 ± .68 mm in the control group and 5.95 ± 1.14 mm in the IS group. EFT was significantly greater in the IS patients in relation to the control group (P < .001). Mean NLR was significantly greater among IS patients in relation to the control group (2.5 ± .6 vs. 1.8 ± .4, P < .001). No significant confounding factors were identified in the data set. Spearman's correlation analysis revealed a mild, but highly significant correlation between EFT and NLR (r = .293, P = .006).

CONCLUSIONS

This study demonstrates for the first time the association between EFT and cerebral IS. Echocardiographic EFT was significantly correlated with NLR. NLR and echocardiographic EFT represent inexpensive and readily available clinical markers that maybe useful in estimating risk of IS.

A low serum free triiodothyronine level is associated with epicardial adipose tissue in peritoneal dialysis patients

AIM

Cardiovascular disease is a major cause of mortality in dialysis patients. Epicardial adipose tissue (EAT) has been proposed as a cardiovascular risk marker in this population. Subclinical hypothyroidism and low free triiodothyronine (fT3) levels are associated with EAT in patients without chronic renal failure. The aim of this study was to investigate the relationship between EAT and low free T3 levels in peritoneal dialysis (PD) patients.

METHODS

A total of 125 prevalent PD patients were enrolled in this cross-sectional study. The epicardial fat thickness (EFT) was measured by echocardiography, and the endothelial function was assessed by flow mediated dilatation (FMD). Thyroid function tests were performed by an enzyme immunoassay.

RESULTS

The mean age of the patients was 51 ± 13, and the time on PD was 36 months. The mean EFT was 6.7 ± 2.9 mm. The EFT correlated positively with the patient age, systolic blood pressure (BP), mean BP, high sensitivity C-reactive protein (hs-CRP) level and body mass index (BMI), and negatively with the fT3 level and FMD. The median fT3 value was 2.53, and patients were divided according to their serum fT3 values (within the normal range and below the reference level). Compared with patients in the low fT3 group, the subjects in the normal fT3 group had higher serum albumin levels and FMD, but a lower BMI, plasma fasting glucose level, EFT, TSH level, hs-CRP level, low density lipoprotein (LDL) cholesterol level and mean BP in office measurements, and both the diastolic BP and mean BP by ambulatory blood pressure measurement. A multivariate linear regression analysis showed that the EFT was predicted by the hs-CRP and fT3 levels.

CONCLUSION

Low free T3 levels are associated with the epicardial fat thickness in PD patients. Further studies are needed to evaluate the pathogenesis and to support these findings.

Epicardial fat and vascular risk: a narrative review

PURPOSE OF REVIEW

We comment on the associations between epicardial adiposity and cardiovascular disease (CVD) and associated risk factors. The effects of lifestyle measures and CVD drugs on cardiac adipose tissue are also discussed.

RECENT FINDINGS

Epicardial adipose tissue exerts cardioprotective properties; however, in cases of pathological enlargement, epicardial fat can lead to myocardial inflammation and dysfunction as well as left ventricular hypertrophy and coronary artery disease (CAD) due to paracrine actions that include increased production of reactive oxygen species, atherogenic and inflammatory cytokines. Cardiac adiposity is associated with CAD, obesity, type 2 diabetes, metabolic syndrome, nonalcoholic fatty liver disease, and chronic kidney disease, as well as with CVD risk factors such as lipids, hypertension, obesity markers, and carotid atherosclerosis.

SUMMARY

Due to its anatomical and functional proximity to the coronary circulation, epicardial adipose tissue may represent an even more direct CVD risk marker than central adiposity. Lifestyle measures and certain drugs may affect its thickness, although there are limited data currently available. The clinical implications of epicardial fat in daily practice remain to be established in future studies.

Increased epicardial adipose tissue thickness is linked to aortic stiffness in patients with primary hypertension

AIMS

In patients with hypertension (HT), increased aortic stiffness is related to higher cardiovascular morbidity and mortality. Recent investigations have shown that epicardial adipose tissue (EAT) is a new potential cardiometabolic risk factor. The aim of our study was to examine the relation between echocardiographically measured EAT thickness and aortic stiffness in patients with primary HT.

METHODS

The study included 144 newly diagnosed and untreated essential hypertensive outpatients. Transthoracic echocardiographic EAT thickness and aortic stiffness measurements were performed for all study participants. Afterwards patients were divided in two groups according to their median EAT thickness values. The patients with EAT thickness of < 7 mm were included in group 1 and patients with EAT thickness of ≥ 7 mm were included in group 2.

RESULTS

Aortic strain and distensibility parameters of group 2 were lower than in group 1. The aortic stiffness index of group 2 was found to be higher than group 1. Multivariate regression analysis revealed that EAT thickness was the only independent variable for all three parameters of aortic stiffness index, aortic strain and aortic distensibility.

CONCLUSION

In patients with newly diagnosed primary HT, increased EAT thickness was significantly linked to impaired aortic elastic properties independently of other conventional adiposity measurements.

New inflammatory predictors for non-valvular atrial fibrillation: echocardiographic epicardial fat thickness and neutrophil to lymphocyte ratio

The objective of this study was to investigate the relationship of echocardiographic epicardial fat thickness (EFT) and neutrophil to lymphocyte ratio (NLR) with different types of non-valvular atrial fibrillation (AF) in a clinical setting. A total of 197 consecutive patients were enrolled in the study. Seventy-one patients had paroxysmal non-valvular AF, 63 patients had persistent/permanent non-valvular AF, and 63 patients had sinus rhythm (control group). EFT was measured with echocardiography, while NLR was measured by dividing neutrophil count by lymphocyte count. EFT was significantly higher in patients with paroxysmal non-valvular AF compared with those in the sinus rhythm group (6.6 ± 0.7 vs. 5.0 ± 0.9 mm, p < 0.001). Persistent/permanent non-valvular AF patients had a significantly larger EFT compared with those with paroxysmal AF (8.3 ± 1.1 vs. 6.6 ± 0.7 mm, p < 0.001). EFT had a significant relationship with paroxysmal non-valvular AF (odds ratio 4.672, 95 % CI 2.329-9.371, p < 0.001) and persistent/permanent non-valvular AF (OR 24.276, 95% CI 9.285-63.474, p < 0.001). NLR was significantly higher in those with paroxysmal non-valvular AF compared with those in the sinus rhythm group (2.5 ± 0.6 vs. 1.8 ± 0.4, p < 0.001). Persistent/permanent non-valvular AF patients had a significantly larger NLR when compared with paroxysmal non-valvular AF patients (3.4 ± 0.6, vs. 2.5 ± 0.6, p < 0.001). NLR (>2.1) had a significant relationship with non-valvular AF (OR 11.313, 95% CI 3.025-42.306, b 2.426, p < 0.001). EFT and NLR are highly associated with types of non-valvular AF independent of traditional risk factors. EFT measured by echocardiography and NLR appears to be related to the duration and severity of AF.

Increased epicardial adipose tissue thickness as a predictor for hypertension: a cross-sectional observational study

The aim of the study was to determine whether epicardial adipose tissue thickness (EAT), a new cardiometabolic risk factor, is associated with essential hypertension. The sample included 127 asymptomatic patients with one or more cardiovascular risk factors consecutively referred for cardiac computed tomography angiography. Data were collected retrospectively and compared between hypertensive (n=39) and normotensive (n=88) patients. The hypertensive patients had a significantly higher mean EAT thickness than the normotensive group (2.81±1.6 mm vs 2.07±1.43 mm; P=.011) and a significantly elevated mean coronary artery calcium score (316.8±512.6 vs 108.73±215; P=.0257). The odds ratio for a patient with tissue thickness ≥2.4 mm having hypertension was 1.396 (95% confidence interval, 1.033-1.922). Factors independently associated with hypertension were body mass index, low-density lipoprotein, and age. A model score was developed using the logistic regression coefficients for calculation of individual risk. Hypertensive patients have significantly higher than normal EAT thickness. Epicardial adipose tissue thickness may serve as a risk indicator for hypertension and cardiovascular morbidity.

Relation of epicardial fat thickness and brachial flow-mediated vasodilation with coronary artery disease

OBJECTIVE

The purpose of this study is to investigate the presence of a statistical association between epicardial fat thickness (EFT) and coronary artery disease (CAD) and between flow-mediated vasodilation (FMD) and CAD.

METHODS

We measured the EFT and FMD in 64 subjects with suspected stable angina pectoris. The patients were separated into two groups according to their coronary angiography results: 34 patients with CAD and 30 patients with normal coronary arteries (NCA).

RESULTS

EFT was significantly higher in the patients with CAD than the NCA group (6.43 ± 0.90 mm vs. 5.35 ± 0.75 mm, p<0.001) while FMD was significantly lower in the patients with CAD than those in the NCA group (6.41 ± 2.51% vs. 8.33 ± 3.45%, p=0.015). No significant correlation was found between EFT and FMD. After adjustment for EFT, FMD, age, sex, ejection fraction, glucose, and low-density lipoprotein cholesterol through multivariate logistic regression analysis, EFT (odds ratio: 6.325, 95% confidence interval 2.289-17.476, p<0.001) and age (odds ratio: 1.093, 95% confidence interval 1.008-1.185, p=0.032) remained significant predictors of CAD. A cut-off value of EFT≥5.8mm predicted the presence of CAD with 77% sensitivity and 70% specificity.

CONCLUSION

An echocardiographic EFT assessment is independently associated with the presence of CAD. Thus, EFT may be helpful in cardiometabolic risk stratification and therapeutic interventions.