Effects of Bariatric Surgery on Cardiac Ectopic Fat Lesser Decrease in Epicardial Fat Compared to Visceral Fat Loss and No Change in Myocardial Triglyceride Content

ObjectivesThis study investigated the effect of bariatric surgery (BS)–induced weight loss on cardiac ectopic fat using 3T magnetic resonance imaging in morbid obesity.BackgroundHeart disease is one of the leading causes of mortality and morbidity in obese patients. Deposition of cardiac ectopic fat has been related to increased heart risk. Whether sustained weight loss can modulate epicardial fat or myocardial fat is unknown.MethodsTwenty-three morbidly obese patients underwent 1H-magnetic resonance spectroscopy to determine myocardial triglyceride content (MTGC), magnetic resonance imaging to assess epicardial fat volume (EFV), cardiac function, and computed tomography visceral abdominal fat (VAF) measurements at baseline and 6 months after BS.ResultsThe BS reduced body mass index significantly, from 43.1 ± 4.5 kg/m2 to 32.3 ± 4.0 kg/m2, subcutaneous fat from 649 ± 162 cm2 to 442 ± 127 cm2, VAF from 190 ± 83 cm2 to 107 ± 44 cm2, and EFV from 137 ± 37 ml to 98 ± 25 ml (all p < 0.0001). There was no significant change in MTGC: 1.03 ± 0.2% versus 1.1 ± 0.2% (p = 0.85). A significant reduction in left ventricular mass (118 ± 24 g vs. 101 ± 18 g) and cardiac output (7.1 ± 1.6 l/min vs. 5.4 ± 1.0 l/min) was observed and was statistically associated with weight loss (p < 0.05). The loss in EFV was limited (−27 ± 11%) compared to VAF diminution (−40 ± 19%). The EFV variation was not correlated with percentage of body mass index or VAF loss (p = 0.007). The ratio of %EFV to %VAF loss decreased with sleep apnea syndrome (1.34 ± 0.3 vs. 0.52 ± 0.08, p < 0.05).ConclusionsSix-month BS modulates differently cardiac ectopic fat deposition, with a significant decrease in epicardial fat and no change in myocardial fat. Epicardial fat volume loss was limited in patients with sleep apnea. (Impact of Bariatric Surgery on Epicardial Adipose Tissue and on Myocardial Function; NCT01284816

Exenatide decreases ectopic fat accumulation but have no impact on myocardial function and perfusion in patients with obesity and type 2 diabetes

International audienceThe objective of the study is to assess the impact of Exenatide on endothelial reactivity, and change in ectopic fat and cardiac function. This study included 44 patients (mean 52 years) randomized to Exenatide or reference treatment. Magnetic resonance imaging was used to assess ectopic fat accumulation, coronary vasoreactivity and cardiac function. 16-weeks of Exenatide treatement resulted in a significant improvement in glycemic control and a significant reduction of both epicardial fat and hepatic steatosis. However, we found no effect of Exenatide on myocardial function. In addition, one-week of exenatide treatment had only a modest effect on vascular reactivity, albeit non-significant

Exenatide decreases ectopic fat accumulation but have no impact on myocardial function and perfusion in patients with obesity and type 2 diabetes

International audienceThe objective of the study is to assess the impact of Exenatide on endothelial reactivity, and change in ectopic fat and cardiac function. This study included 44 patients (mean 52 years) randomized to Exenatide or reference treatment. Magnetic resonance imaging was used to assess ectopic fat accumulation, coronary vasoreactivity and cardiac function. 16-weeks of Exenatide treatement resulted in a significant improvement in glycemic control and a significant reduction of both epicardial fat and hepatic steatosis. However, we found no effect of Exenatide on myocardial function. In addition, one-week of exenatide treatment had only a modest effect on vascular reactivity, albeit non-significant

Time Course of Change in Ectopic Fat Stores After Bariatric Surgery.

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Cushing Syndrome Is Associated With Subclinical LV Dysfunction and Increased Epicardial Adipose Tissue

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Effects of contrast agents on relaxation properties of 31P metabolites.

PURPOSE: Phosphorous MR spectroscopy (31P-MRS) forms a powerful, non-invasive research tool to quantify the energetics of the heart in diverse patient populations. 31P-MRS is frequently applied alongside other radiological examinations, many of which use various contrast agents that shorten relaxation times of water in conventional proton MR, for a better characterisation of cardiac function, or following prior computed tomography (CT). It is, however, unknown whether these agents confound 31P-MRS signals, for example, 2,3-diphosphoglycerate (2,3-DPG). METHODS: In this work, we quantitatively assess the impact of non-ionic, low osmolar iodinated CT contrast agent (iopamidol/Niopam), gadolinium chelates (linear gadopentetic acid dimeglumine/Magnevist and macrocyclic gadoterate meglumine/Dotarem) and superparamagnetic iron oxide nanoparticles (ferumoxytol/Feraheme) on the nuclear T1 and T2 of 31P metabolites (ie, 2,3-DPG), and 1H in water in live human blood and saline phantoms at 11.7 T. RESULTS: Addition of all contrast agents led to significant shortening of all relaxation times in both 1H and 31P saline phantoms. On the contrary, the T1 relaxation time of 2,3-DPG in blood was significantly shortened only by Magnevist (P = .03). Similarly, the only contrast agent that influenced the T2 relaxation times of 2,3-DPG in blood samples was ferumoxytol (P = .02). CONCLUSION: Our results show that, unlike conventional proton MR, phosphorus MRS is unconfounded in patients who have had prior CT with contrast, not all gadolinium-based contrast agents influence 31P-MRS data in vivo, and that ferumoxytol is a promising contrast agent for the reduction in 31P-MRS blood-pool signal.CTR and LV thank the funding of a Sir Henry Dale Fellowship from the Wellcome Trust and the Royal Society (098436/Z/12/B). JJM would like to acknowledge the support of a Novo Nordisk Postdoctoral Fellowship and a Junior Research Fellowship at Wadham College Oxford. Authors also acknowledge the support of the British Heart Foundation (refs. FS/14/17/30634 and FS/16/7/31843). The support of the Slovak Grant Agency VEGA (grant #2/0003/20) and APVV (grant #19-0032) is acknowledged by LV and IF

A Heterozygous ZMPSTE24 Mutation Associated with Severe Metabolic Syndrome, Ectopic Fat Accumulation, and Dilated Cardiomyopathy

ZMPSTE24 encodes the only metalloprotease, which transforms prelamin into mature lamin A. Up to now, mutations in ZMPSTE24 have been linked to Restrictive Dermopathy (RD), Progeria or Mandibulo-Acral Dysplasia (MAD). We report here the phenotype of a patient referred for severe metabolic syndrome and cardiomyopathy, carrying a mutation in ZMPSTE24. The patient presented with a partial lipodystrophic syndrome associating hypertriglyceridemia, early onset type 2 diabetes, and android obesity with truncal and abdominal fat accumulation but without subcutaneous lipoatrophy. Other clinical features included acanthosis nigricans, liver steatosis, dilated cardiomyopathy, and high myocardial and hepatic triglycerides content. Mutated fibroblasts from the patient showed increased nuclear shape abnormalities and premature senescence as demonstrated by a decreased Population Doubling Level, an increased beta-galactosidase activity and a decreased BrdU incorporation rate. Reduced prelamin A expression by siRNA targeted toward LMNA transcripts resulted in decreased nuclear anomalies. We show here that a central obesity without subcutaneous lipoatrophy is associated with a laminopathy due to a heterozygous missense mutation in ZMPSTE24. Given the high prevalence of metabolic syndrome and android obesity in the general population, and in the absence of familial study, the causative link between mutation and phenotype cannot be formally established. Nevertheless, altered lamina architecture observed in mutated fibroblasts are responsible for premature cellular senescence and could contribute to the phenotype observed in this patient

Lipodystrophy-like features after total body irradiation among survivors of childhood acute leukemia

Background/objective: The number of long-term survivors of childhood acute leukemia (AL) is substantially growing. These patients are at high risk for metabolic syndrome (MS), especially those who received total body irradiation (TBI). The consequences of children's irradiation on adipose tissue (AT) development in adulthood are currently unknown. The objective of this study is to assess the impact of TBI on AT of childhood AL survivors. Design: We compared the morphological and functional characteristics of AT among survivors of childhood AL who developed MS and received (n = 12) or not received (n = 12) TBI. Subjects/methods: Body fat distribution and ectopic fat stores (abdominal visceral and liver fat) were evaluated by DEXA, MRI and 1H-spectroscopy. Functional characteristics of subcutaneous AT were investigated by studying gene expression and pre-adipocyte differentiation in culture. Results: Patients who have received TBI exhibited a lower BMI (minus 5 kg/m(2)) and a lower waist circumference (minus 14 cm), especially irradiated women. Despite the lower quantity of intra-abdominal AT, irradiated patient displayed a nearly two-fold greater content of liver fat when compared to non-irradiated patient (17 vs 9%, P = 0.008). These lipodystrophic-like features are supplemented by molecular abnormalities in subcutaneous AT of irradiated patients: decrease of gene expression of SREBP1 (minus 39%, P = 0.01) and CIDEA (minus 36%, P = 0.004) and a clear alteration of pre-adipocyte differentiation. Conclusions: These results strongly support the direct effect of irradiation on AT, especially in women, leading to specific nonalcoholic fatty liver disease, despite lower BMI. A long-term appropriate follow-up is necessary for these patients

Active cushing syndrome patients have increased ectopic fat deposition and bone marrow fat content compared to cured patients and healthy subjects: a pilot 1H-MRS study

International audienceOBJECTIVE: Glucocorticoid excess is one of the most important causes of bone disorders. Bone marrow fat (BMF) has been identified as a l new mediator of bone metabolism. Cushing syndrome (CS), is a main regulator of adipose tissue distribution but its impact on BMF is unknown. The objective of the study was to evaluate the effect of chronic hypercortisolism on BMF. DESIGN: This was a cross-sectional study. Seventeen active and seventeen cured ACTH-dependent CS patients along with seventeen controls (matched with the active group for age and sex) were included. METHODS: the BMF content of the femoral neck and L3 vertebrae were measured by 1H-MRS on a 3-Tesla wide-bore magnet. BMD was evaluated in patients using dual-energy X-ray absorptiometry. RESULTS: Active CS patients had higher BMF content both in the femur (82.5±2.6%) and vertebrae (70.1±5.1%) compared to the controls (70.8±3.6%, p=0.013 and 49.0±3.7% p=0.005, respectively). In cured CS patients (average remission time of 43 months), BMF content was not different from controls at both sites (72.3±2.9% (femur) and 46.7%±5.3% (L3)). BMF content was positively correlated with age, fasting plasma glucose, HbA1c, triglycerides and visceral adipose tissue in the whole cohort and negatively correlated with BMD values in the CS patients . CONCLUSIONS: Accumulation of BMF is induced by hypercortisolism. In remission patients BMF reached values of controls. Further studies are needed to determine whether this increase in marrow adiposity in CS is associated with bone loss