Abnormal longitudinal peak systolic strain in asymptomatic patients with type I diabetes mellitus.

AIMS: In addition to increased risk of cardiovascular disease, the prevalence of diabetic cardiomyopathy is increasingly recognized in patients with type 1 diabetes mellitus (T1DM). We aimed to identify the occurrence of subclinical markers of cardiovascular risk and cardiac dysfunction and assess their relation to clinical parameters in asymptomatic patients with T1DM. METHODS AND RESULTS: A total of 102 patients (mean age 46 years [20-73], 62% male) with a history of T1DM ranging from 5 to 47 years underwent standard 2D and pulse-wave tissue Doppler echocardiography (Philips iE33) and computerized tomography for assessment of coronary calcium score (CACS) and visceral fat. Global peak longitudinal strain (GPLSS, speckle tracking) was calculated by offline analysis (Qlab 9.0). Whereas systolic function was preserved in all patients (LVEF > 50%), subclinical dysfunction (defined as global longitudinal peak systolic strain [GLPSS] of >-20%) was present in 39% and 66% had diastolic dysfunction. Fifty patients had a CACS above the 50th percentile according to age and gender. These patients were older, more obese, had higher levels of visceral fat, higher SBP and increased levels of LDL cholesterol. Higher CACS meant increased risk of diastolic and subclinical systolic dysfunction. However, decreased GLPSS was also detected in 30% of patients with CACS of <50th percentile. Stepwise linear regression analysis indicated visceral fat as a strong predictor of abnormal GPLSS and CACS. CONCLUSION: Subclinical left ventricular dysfunction and atherosclerosis were highly prevalent in asymptomatic T1DM. Abnormal GPLSS was noted with or without associated increase in CACS. Visceral fat was a strong predictor of increased CACS as well as abnormal GLPSS.

Tumor necrosis factor-α impairs adiponectin signalling, mitochondrial biogenesis, and myogenesis in primary human myotubes cultures.

Skeletal muscle metabolic changes are common in patients with chronic heart failure (HF). Previously, we demonstrated a functional skeletal muscle adiponectin resistance in HF patients with reduced left ventricular ejection fraction (HFrEF). We aimed to examine the impact of adiponectin receptor 1 (AdipoR1) deficiency and TNF-α treatment on adiponectin signaling, proliferative capacity, myogenic differentiation, and mitochondrial biogenesis in primary human skeletal muscle cells. Primary cultures of myoblasts and myotubes were initiated from the musculus vastus lateralis of 10 HFrEF patients (left ventricular ejection fraction; 31.30 ± 2.89%) and 10 age- and gender-matched healthy controls. Healthy control cultures were transfected with siAdipoR1 and/or exposed to TNF-α (10 ng/ml; 72 h). Primary cultures from HFrEF patients preserved the features of adiponectin resistance in vivo. AdipoR1 mRNA was negatively correlated with time to reach maximal cell index (r = -0.7319, P = 0.003). SiRNA-mediated AdipoR1 silencing reduced pAMPK (P < 0.01), AMPK activation (P = 0.046), and myoblast proliferation rate (xCELLigence Real-Time Cellular Analysis; P < 0.0001). Moreover, TNF-α decreased the mRNA expression of genes involved in glucose (APPL1, P = 0.0002; AMPK, P = 0.021), lipid (PPARα, P = 0.025; ACADM, P = 0.003), and mitochondrial (FOXO3, P = 0.018) metabolism, impaired myogenesis (MyoD1, P = 0.053; myogenin, P = 0.048) and polarized cytokine secretion toward a growth-promoting phenotype (IL-10, IL-1ß, IFN-γ, P < 0.05 for all; Meso Scale Discovery Technology). Major features of adiponectin resistance are retained in primary cultures from the skeletal muscle of HFrEF patients. In addition, our results suggest that an increased inflammatory constitution contributes to adiponectin resistance and confers alterations in skeletal muscle differentiation, growth, and function.

Primary skeletal muscle myoblasts from chronic heart failure patients exhibit loss of anti-inflammatory and proliferative activity.

BACKGROUND: Peripheral skeletal muscle wasting is a common finding with adverse effects in chronic heart failure (HF). Whereas its clinical relevance is beyond doubt, the underlying pathophysiological mechanisms are not yet fully elucidated. We aimed to introduce and characterize the primary culture of skeletal muscle cells from individual HF patients as a supportive model to study this muscle loss. METHODS AND RESULTS: Primary myoblast and myotubes cultures were successfully propagated from the m. vastus lateralis of 6 HF patients with reduced ejection fraction (HFrEF; LVEF <45 %) and 6 age and gender-matched healthy donors. HFrEF cultures were not different from healthy donors in terms of morphology, such as myoblast size, shape and actin microfilament. Differentiation and fusion indexes were identical between groups. Myoblast proliferation in logarithmic growth phase, however, was attenuated in the HFrEF group (p = 0.032). In addition, HFrEF myoblasts are characterized by a reduced TNFR2 expression and IL-6 secretion (p = 0.017 and p = 0.016; respectively). CONCLUSION: Biopsy derived primary skeletal muscle myoblasts of HFrEF patients produce similar morphological and myogenic differentiation responses as myoblasts of healthy donors, though demonstrate loss of anti-inflammatory and proliferative activity.

Adiponectin: key role and potential target to reverse energy wasting in chronic heart failure.

The concept of skeletal muscle myopathy as a main determinant of exercise intolerance in chronic heart failure (HF) is gaining acceptance. Symptoms that typify HF patients, including shortness of breath and fatigue, are often directly related to the abnormalities of the skeletal muscle in HF. Besides muscular wasting, alterations in skeletal muscle energy metabolism, including insulin resistance, have been implicated in HF. Adiponectin, an adipocytokine with insulin-sensitizing properties, receives increasing interest in HF. Circulating adiponectin levels are elevated in HF patients, but high levels are paradoxically associated with poor outcome. Previous analysis of m. vastus lateralis biopsies in HF patients highlighted a striking functional adiponectin resistance. Together with increased circulating adiponectin levels, adiponectin expression within the skeletal muscle is elevated in HF patients, whereas the expression of the main adiponectin receptor and genes involved in the downstream pathway of lipid and glucose metabolism is downregulated. In addition, the adiponectin-related metabolic disturbances strongly correlate with aerobic capacity (VO2 peak), sub-maximal exercise performance and muscle strength. These observations strengthen our hypothesis that adiponectin and its receptors play a key role in the development and progression of the "heart failure myopathy". The question whether adiponectin exerts beneficial rather than detrimental effects in HF is still left unanswered. This current research overview will elucidate the emerging role of adiponectin in HF and suggests potential therapeutic targets to tackle energy wasting in these patients.

Unraveling new mechanisms of exercise intolerance in chronic heart failure: role of exercise training.

Despite remarkable progress in the therapeutic approach of patients with chronic heart failure (CHF), exercise intolerance remains one of the hallmarks of the disease. During the past two decades, evidence has accumulated to underscore the key role of both endothelial dysfunction and skeletal muscle wasting in the process that gradually leads to physical incapacity. Whereas reverse ventricular remodeling has been attributed to aerobic exercise training, the vast majority of studies conducted in this specific patient population emphasize the reversal of peripheral abnormalities. In this review, we provide a general overview on underlying pathophysiological mechanisms. In addition, emphasis is put on recently identified pathways, which contribute to a deeper understanding of the main causes of exercise tolerance and the potential for reversal through exercise training. Recently, deficient bone marrow-related endothelial repair mechanisms have received considerable attention. Both acute exercise bouts, as well as exercise training, affect the mobilization of endothelial progenitor cells and their function. The observed changes following exercise training are believed to significantly contribute to improvement of peripheral endothelial function, as well as exercise capacity. With regard to skeletal muscle dysfunction and energy deprivation, adiponectin has been suggested to play a significant role. The demonstration of local skeletal muscle adiponectin resistance may provide an interesting and new link between the insulin resistant state and skeletal muscle wasting in CHF patients.

Functional adiponectin resistance and exercise intolerance in heart failure.

The contribution of skeletal muscle myopathy to the phenotype of patients with chronic heart failure (CHF) has become generally accepted. Besides the macro- and microscopic changes that develop during the progressive process of muscular wasting, functional abnormalities manifest in an earlier stage. Analogous to the failing heart, alterations in skeletal muscle energy metabolism, including insulin resistance, are increasingly recognized. In the search for factors causing this observed myopathy, adipokines receive growing attention. In particular, adiponectin is of special interest due to its fundamental role in skeletal muscle energy metabolism. In strong contrast with patients at risk for cardiovascular disease, circulating adiponectin levels are increased in patients with CHF, and this finding is associated with adverse outcome. Recently, the concept of functional skeletal muscle adiponectin resistance has been suggested to explain compensatory elevated adiponectin levels in CHF. Unraveling of adiponectin's complex downstream signalling pathways and insights into the concept of adiponectin resistance hopefully will disengage the road for targeted therapeutic interventions.

Multi-plane echocardiographic assessment of right ventricular function in adults with repaired Tetralogy of Fallot.

In patients with repaired Tetralogy of Fallot (ToF), detailed assessment of right ventricular (RV) function is important for management and timing of possible pulmonary valve re-intervention. The aim of this study was to evaluate RV function using two-dimensional multi-plane echocardiography (2D MPE), a novel four-wall imaging method obtained from one apical acoustic window utilising electronic plane rotation. In sixty-two ToF patients (aged - 28 [22, 39] years, 65% male), systolic function of four different RV walls (lateral, anterior, inferior and inferior coronal) were evaluated using MPE. Tricuspid annular plane systolic excursion (TAPSE), tricuspid annular peak systolic velocity (RV-S') and RV wall longitudinal strain (RV-LS) measurements were compared with those of matched healthy individuals. 2D MPE measurements were highly feasible across the four RV walls (93.5-100% for TAPSE/S'; 66.1-95.1% for RVLS) and could be performed more reliably than 3D RV ejection fraction (RVEF - 56.5%). All functional values were significantly reduced when compared to the control group (p < 0.001). Higher RV-LS values were seen in the lateral (- 17.8 ± 4.5%) and inferior (- 17.8 ± 4.2%) walls compared to the anterior (- 15.9 ± 3.8%) and inferior coronal (- 15.1 ± 3.9%) walls. 3D RVEF correlated strongest with RV-LS values from the lateral (r - 0.50; p = 0.002) and anterior walls (r - 0.74; p < 0.001) and furthermore the four-wall average (r - 0.57; p = 0.001). 2D MPE evaluation of the RV is highly feasible in ToF patients. This novel method provides new insights into regional RV wall function, enabling a more comprehensive and quantitative approach to RV assessment in daily clinical practice.

Quantitative assessment of the entire right ventricle from one acoustic window: An attractive approach in patients with congenital heart disease in daily practice.

BACKGROUND: Right ventricular (RV) function is recognized as an important prognostic factor in adult congenital heart disease (ACHD). The accuracy of established parameters including tricuspid annular plane systolic excursion (TAPSE), RV fractional area change (RVFAC) and tissue Doppler imaging (TDI S') is limited as only a small RV region is reflected. We previously introduced a novel four-view approach with different RV walls visualized from one apical view using electronic plane rotation, also known as iRotate. AIM: To evaluate the entire RV function using electronic plane rotation echocardiography within the spectrum of ACHD compared with healthy subjects. METHODS AND RESULTS: One hundred and forty-two ACHD patients were recruited from the outpatient clinic and 89 healthy subjects. All subjects underwent a transthoracic echocardiogram with evaluation of TAPSE, TDI S' and peak systolic longitudinal RV strain (RV-LS) from all RV walls using the four-view electronic plane rotation model. With exception of TDI S' in inferior coronal view, all parameters were lower in ACHD vs healthy subjects (p < 0.001). Within the ACHD patients, RV strain was lower in anterior (-15.9 ± 4.9) and inferior coronal view (-15.1 ± 4.5) versus lateral (-17.6 ± 5.0) and inferior wall (-17.2 ± 4.7) (p < 0.05). RV-LS values of systemic RV were lower (p < 0.05), but no difference was observed between subpulmonic RV loading conditions. CONCLUSION: The four-view electronic plane rotation model represents a reproducible, easily applicable and complete RV assessment in daily practice. RV function is significantly decreased in the ACHD group using both regional and global assessment parameters. Complete RV strain analysis reveals regional differences.

Exercise training reduces circulating adiponectin levels in patients with chronic heart failure.

High adiponectin concentrations have emerged as an independent risk factor of outcome inpatients with CHF (chronic heart failure); however, modification of adiponectin in CHF patients has not been assessed to date. The aim of the present study was to investigate the effect of exercise training on adiponectin levels in CHF patients. A total of 80 patients with CHF due to systolic dysfunction were included. The effect of 4 months exercise training was studied in 46 patients,whereas the remaining 34 untrained CHF patients served as a sedentary control group. Circulating adiponectin concentrations, exercise capacity, anthropometric data and NT-proBNP (N-terminal pro-brain natriuretic peptide) levels were assessed. Adiponectin levels were significantly higher in CHF patients compared with healthy subjects [9.3 (7.1-16.1) and 4.9 (3.9-8.6) mg/l respectively;P=0.015]. Stratification of CHF patients according to tertiles of NT-proBNP revealed an increase in adiponectin with disease severity (P<0.0001). Exercise training reduced circulating adiponectin levels in CHF patients [10.7 (7.2-17.6) mg/l before training to 9.4 (5.9-14.8) mg/l after training;P=0.013], whereas no changes were observed in the sedentary CHF group [9.0 (7.0-13.5) mg/l before training and 10.1 (6.0-15.7) mg/l after a similar time interval]. A significant time x group interaction (P=0.008) was observed for the mean change in adiponectin between the trained and untrained CHF patients. Adiponectin concentrations were positively associated with NT-proBNP and HDL (high-density lipoprotein)-cholesterol and negatively correlated with BMI (body mass index), triacylglycerols and exercise capacity. In conclusion, circulating adiponectin concentrations are higher in CHF patients compared with healthy subjects and increase with disease severity.Exercise training for 4 months lowers circulating adiponectin levels.

The Effect of Exercise Training During Pregnancy to Improve Maternal Vascular Health: Focus on Gestational Hypertensive Disorders.

Hypertensive disorders of pregnancy, including gestational hypertension and pre-eclampsia, occur in up to 10% of pregnancies and are associated with increased life-long cardiovascular risk. Physical activity improves cardiovascular health in pregnancy and may lower the risk of developing hypertensive disorders of pregnancy. However, a minority of pregnant women comply with the recommended level of physical activity. Adequate knowledge on the physiological effects of exercise in healthy pregnancy could help to overcome potential barriers as pregnancy is a unique window of opportunity to improve health outcomes for both mother and child. In this mini review, we discuss structural and functional vascular adaptations during healthy and hypertensive pregnancies, we elaborate on the effects of exercise on the vasculature and review the safety and existing evidence of exercise training as preventive therapy for gestational hypertensive disorders.

Left ventricular global longitudinal strain in bicupsid aortic valve patients: head-to-head comparison between computed tomography, 4D flow cardiovascular magnetic resonance and speckle-tracking echocardiography.

Left ventricular global longitudinal strain (LVGLS) analysis is a sensitive measurement of myocardial deformation most often done using speckle-tracking transthoracic echocardiography (TTE). We propose a novel approach to measure LVGLS using feature-tracking software on the magnitude dataset of 4D flow cardiovascular magnetic resonance (CMR) and compare it to dynamic computed tomography (CT) and speckle tracking TTE derived measurements. In this prospective cohort study 59 consecutive adult patients with a bicuspid aortic valve (BAV) were included. The study protocol consisted of TTE, CT, and CMR on the same day. Image analysis was done using dedicated feature-tracking (4D flow CMR and CT) and speckle-tracking (TTE) software, on apical 2-, 3-, and 4-chamber long-axis multiplanar reconstructions (4D flow CMR and CT) or standard apical 2-, 3-, and 4-chamber acquisitions (TTE). CMR and CT GLS analysis was feasible in all patients. Good correlations were observed for GLS measured by CMR (- 21 ± 3%) and CT (- 20 ± 3%) versus TTE (- 20 ± 3%, Pearson's r: 0.67 and 0.65, p < 0.001). CMR also correlated well with CT (Pearson's r 0.62, p < 0.001). The inter-observer analysis showed moderate to good reproducibility of GLS measurement by CMR, CT and TTE (Pearsons's r: 0.51, 0.77, 0.70 respectively; p < 0.05). Additionally, ejection fraction (EF), end-diastolic and end-systolic volume measurements (EDV and ESV) correlated well between all modalities (Pearson's r > 0.61, p < 0.001). Feature-tracking GLS analysis is feasible using the magnitude images acquired with 4D flow CMR. GLS measurement by CMR correlates well with CT and speckle-tracking 2D TTE. GLS analysis on 4D flow CMR allows for an integrative approach, integrating flow and functional data in a single sequence. Not applicable, observational study.

Adiponectin resistance in skeletal muscle: pathophysiological implications in chronic heart failure.

Skeletal muscle wasting is a common complication of chronic heart failure (CHF) and linked to poor patient prognosis. In recent years, adiponectin was postulated to be centrally involved in CHF-associated metabolic failure and muscle wasting. This review discusses current knowledge on the role of adiponectin in CHF. Particular emphasis will be given to the complex interaction mechanisms and the intracellular pathways underlying adiponectin resistance in skeletal muscle of CHF patients. In this review, we propose that the resistance process is multifactorial, integrating abnormalities emanating from insulin signalling, mitochondrial biogenesis, and ceramide metabolism.

Disturbed adiponectin ­ AMPK system in skeletal muscle of patients with metabolic syndrome.

Patients with metabolic syndrome are characterized by low circulating adiponectin levels and reduced adiponectin sensitivity in skeletal muscles. Through binding on its main skeletal muscle receptor AdipoR1, adiponectin activates AMP-activated protein kinase (AMPK), a key player in energy homeostasis. Fourteen metabolic syndrome patients and seven healthy control subjects were included. Blood samples were taken to determine insulin resistance, adiponectin, lipoproteins, and C-reactive protein. Muscle biopsies (m. vastus lateralis) were obtained to assess mRNA expression of AdipoR1 and both AMPKα1 and AMPKα2 subunits, as well as downstream targets in lipid and glucose metabolism. Skeletal muscle mRNA expression of AMPKα1 and AMPKα2 was lower in metabolic syndrome patients (100 ± 6 vs. 122 ± 8 AU, p = 0.030 and 64 ± 4 vs. 85 ± 9 AU, p = 0.044, respectively), whereas the expression of AdipoR1 was upregulated (138 ± 9 vs. 105 ± 7, p = 0.012). AMPKα1 and AdipoR1 correlated positively in both the control (r = 0.964, p < 0.001) and the metabolic syndrome group (r = 0.600, p = 0.023). However, this relation was shifted upwards in metabolic syndrome patients, indicating increased AdipoR1mRNA expression for a similar AMPKα1 expression. Previously, a blunted stimulatory effect of adiponectin on AMPK activation has been shown in metabolic syndrome patients. The present data suggest that the disturbed interaction of adiponectin with AMPK is located downstream of the AdipoR1 receptor.

Impact of exercise testing mode on exercise parameters in patients with chronic heart failure.

AIM: To verify the impact of testing mode on maximal, sub-maximal parameters and on cardiopulmonary exercise test (CPET) derived prognostic markers in patients with chronic heart failure (CHF). METHOD: 55 patients (age 60.3 years ±11.1) with CHF (ejection fraction 26 %±8) underwent a maximal CPET on a bicycle and on a treadmill, in a random order, within one week. Maximal, sub-maximal parameters and CPET derived prognostic markers were compared. RESULTS: VO(2)peak and VO(2)peak corrected for lean body mass were significantly higher on treadmill compared to bicycle (+11%, p < 0.0001). This was also the case for the following sub-maximal parameters; heart rate, workload and VO(2) at ventilatory anaerobic threshold and VO(2) at the respiratory compensation point (RCP). In contrast, both VE/VCO(2) slopes (start to RCP and start to end test) were similar. Time to 1/2 VO(2)peak was longer and circulatory power was higher on the treadmill compared to exercise testing on the bicycle. CONCLUSION: The results of the present study suggest that the mode of exercise testing significantly affects absolute values for VO(2)peak but does not greatly impact the prognostic utility of the VE/VCO(2) slope in patients with moderate to severe CHF. Besides the consequences of these findings in terms of prognostication, testing mode should be taken into consideration when exercise prescription is based on VO(2)peak.

Comparison of three methods to identify the anaerobic threshold during maximal exercise testing in patients with chronic heart failure.

OBJECTIVE: Exercise training efficiently improves peak oxygen uptake (V˙O2peak) in patients with chronic heart failure. To optimize training-derived benefit, higher exercise intensities are being explored. The correct identification of anaerobic threshold is important to allow safe and effective exercise prescription. DESIGN: During 48 cardiopulmonary exercise tests obtained in patients with chronic heart failure (59.6 ± 11 yrs; left ventricular ejection fraction, 27.9% ± 9%), ventilatory gas analysis findings and lactate measurements were collected. Three technicians independently determined the respiratory compensation point (RCP), the heart rate turning point (HRTP) and the second lactate turning point (LTP2). Thereafter, exercise intensity (target heart rate and workload) was calculated and compared between the three methods applied. RESULTS: Patients had significantly reduced maximal exercise capacity (68% ± 21% of predicted V˙O2peak) and chronotropic incompetence (74% ± 7% of predicted peak heart rate). Heart rate, workload, and V˙O2 at HRTP and at RCP were not different, but at LTP2, these parameters were significantly (P < 0.0001) higher. Mean target heart rate and target workload calculated using the LTP2 were 5% and 12% higher compared with those calculated using HRTP and RCP, respectively. The calculation of target heart rate based on LTP2 was 5% and 10% higher in 12 of 48 (25%) and 6 of 48 (12.5%) patients, respectively, compared with the other two methods. CONCLUSIONS: In patients with chronic heart failure, RCP and HRTP, determined during cardiopulmonary exercise tests, precede the occurrence of LTP2. Target heart rates and workloads used to prescribe tailored exercise training in patients with chronic heart failure based on LTP2 are significantly higher than those derived from HRTP and RCP.

ß-blockers modify the prognostic value of adiponectin in chronic heart failure.

BACKGROUND: Recent evidence suggests that high adiponectin levels serve as an independent predictor of mortality in chronic heart failure (CHF) patients. We aimed to assess the prognostic importance of adiponectin in CHF towards heart failure-related hospital admissions and mortality, in relation to other clinical, laboratory and exercise data. METHODS: Seventy-three CHF patients were recruited from the Heart Failure Clinic of the Antwerp University Hospital and followed for a median of 7 (range 1.5-9.1) years. Study endpoint was the combined occurrence of heart failure-related hospitalizations and all-cause death. At baseline patients underwent clinical assessment, echocardiography and cardiopulmonary exercise testing. Circulating concentrations of adiponectin, NT-proBNP and lipoproteins were measured. After follow-up the hazard ratio (HR) of adiponectin for outcome was estimated using multivariable Cox proportional hazard regression analysis. RESULTS: During follow-up, 14 (19%) patients died and 46 (63%) were admitted for CHF deterioration. The unadjusted hazard for poor outcome was higher in patients with adiponectin values above the 75th percentile (15.2mg/L) (P=0.031). Adiponectin remained independently predictive [HR (95% CI) 2.47 (1.21-5.03), P=0.013], when controlling for well-established predictors of mortality/morbidity in CHF. Additional correction for BMI, NT-proBNP, VO(2) peak, HDL and triglycerides did not affect the HR estimate. After adjusting for beta-blocker intake the association between adiponectin and poor outcome was no longer significant. CONCLUSIONS: High adiponectin levels predict poor outcome in CHF patients independently of well-established and novel prognostic factors, but this prognostic value is significantly affected by beta-blocker treatment.

Exercise training reverses adiponectin resistance in skeletal muscle of patients with chronic heart failure.

BACKGROUND: Resistance to the insulin-sensitising adipocytokine, adiponectin, has been described at the level of the skeletal muscle in patients with chronic heart failure (CHF). OBJECTIVE: To investigate whether exercise training (ET) would improve skeletal muscle energy metabolism and adiponectin signalling. METHODS: In a prospective cohort study, patients with CHF were recruited from the Cardiac Rehabilitation Centre, Antwerp University Hospital. They underwent 4 months' combined endurance-resistance ET. Skeletal muscle mRNA and protein expression of adiponectin, AdipoR1 and downstream metabolic genes were measured. RESULTS: Adiponectin mRNA expression in the nine CHF patients was higher than that in 10 matched healthy subjects (p=0.007), whereas AdipoR1 and downstream-located genes involved in lipid (PPAR-α, ACADM) and glucose metabolism (AMPK, hexokinase2) were down-regulated. Skeletal muscle AdipoR1 correlated with VO(2) peak (r=0.900; p=0.001), maximal workload (r=0.753; p=0.019) and steady state workload (r=0.928; p<0.001). ET increased maximal workload and muscle strength. In addition, ET lowered adiponectin mRNA expression (p=0.017), whereas the expression of AdipoR1 (p=0.011) and downstream metabolic genes was increased to levels comparable to those in healthy subjects. ELISA confirmed the normalisation of skeletal muscle adiponectin expression at the protein level (p=0.047). CONCLUSION: At the level of the skeletal muscle, CHF patients are characterised by increased adiponectin expression and decreased expression of AdipoR1 and downstream metabolic genes. ET normalises the mRNA expression of adiponectin and AdipoR1 and reverses disorders in lipid and glucose metabolism in skeletal muscle. These alterations in metabolic gene expression may help to understand the beneficial effects of ET in CHF.

Outcome of acute kidney injury with different treatment options: long-term follow-up.

BACKGROUND AND OBJECTIVES: The multicenter Stuivenberg Hospital Acute Renal Failure 4 study investigated outcome in patients with acute kidney injury (AKI) stratified according to disease severity by the Stuivenberg Hospital Acute Renal Failure score. Patients in need of renal replacement therapy (RRT) received intermittent RRT or continuous RRT. This study investigated long-term mortality, renal function, comorbidity, and quality of life. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: All AKI hospital survivors were included. Mortality at 1 and 2 years of follow-up was traced for all patients. Between 1 and 2 years after hospital discharge, survivors were visited at home to determine morbidity (renal function), comorbidity (Charlson comorbidity index [CCI]), and quality of life (Medical Outcome Survey SF-36). RESULTS: The baseline population consisted of 595 AKI patients. Mortality rates were 23.0 and 7.6%, respectively, during the first and second year after discharge. Total mortality increased from 50.7% at discharge to 65.7% 2 years after AKI and was not related to disease severity or treatment modality offered during hospitalization. Two hundred four survivors could be visited at home. Mean serum creatinine did not differ between discharge and follow-up. CCI was only related with age. SF-36 scores were negatively correlated with CCI, age, and body mass index, but not with disease severity, renal function, or dialysis modality. CONCLUSIONS: Long-term outcome of AKI consists of a high additional mortality unrelated to treatment modality offered during hospitalization, varying evolution of renal recovery, and many comorbidities, but a mental health at the same level as the general population.

Validation of an adiponectin immunoassay in human skeletal muscle biopsies.

Adiponectin is an insulin-sensitizing adipocytokine that circulates in plasma as multimeric isoforms, including trimers, hexamers and high molecular weight complexes. Although adiponectin multimers have previously been measured by Western blot, this remains a relatively delicate technique that is often hampered by high background or multiple bands. We validated a commercially available ELISA, designed to measure total (low, middle and high molecular weight) human adiponectin concentration in cell culture supernatants, serum and plasma, for its proper use in skeletal muscle biopsies obtained in patients with chronic heart failure and healthy controls.