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Amsterdam-Zuidoost, Netherlands

Slagt C.,Koningin Julianaplein 58 | Slagt C.,Zaans Medical Center | Beute J.,Zaans Medical Center | Hoeksema M.,Zaans Medical Center | And 3 more authors.
European Journal of Anaesthesiology | Year: 2010

Background and objective We studied the evolution of software in the accuracy of the FloTrac/Vigileo system to measure cardiac output less invasively from arterial pressure waveform analysis without calibration, in comparison with pulmonary artery catheter-derived thermodilution measurements, in patients with septic shock and presumed alterations in vascular tone. Methods Nine patients who received a pulmonary artery catheter and were on mechanical ventilation and in sinus rhythm were monitored by the FloTrac/Vigileo. Paired cardiac output measurements by both techniques were analysed for 86 measurements in four patients using the 1.07 software version and 73 measurements in five subsequent patients using the later 1.10 version. Results For the 1.07 version, bias was -1.6 L min-1, precision 1.6 L min-1, limits of agreement -4.8-1.5 L min-1 and error 48%. Measurements correlated at partial r equal to 0.32 (P=0.003). For the 1.10 version, bias was -1.2 L min-1, precision 1.1 L min-1, limits of agreement -3.5-1.0 L min-1 and error 32%. Measurements correlated at partial r equal to 0.90 (P<0.001 vs. version 1.07). Differences were inversely related to mean cardiac output (P<0.001, generalized estimating equations), particularly for software version 1.07 vs. 1.10 (P=0.017, generalized estimating equation). Changes in thermodilution cardiac output over the course of time were also better tracked by the FloTrac/Vigileo when applying the latest software (P<0.001, generalized estimating equation). Conclusions Evolving software versions are thus better able to account for the effect of vascular tone on cardiac output measurements by less invasive waveform analyses without calibration (FloTrac/Vigileo), so that the latter may become useful in the haemodynamic monitoring of septic shock. © 2010 Copyright European Society of Anaesthesiology. Source

Ruiter G.,VU University Amsterdam | Ying Wong Y.,VU University Amsterdam | De Man F.S.,VU University Amsterdam | Louis Handoko M.,VU University Amsterdam | And 6 more authors.
Journal of Heart and Lung Transplantation | Year: 2013

Background: In pulmonary arterial hypertension (PAH), high right ventricular (RV) power output requires increased myocardial oxygen consumption. Oxygen supply, however, does not increase in proportion. It is unknown what cellular mechanisms underlie this lack of adaptation. We therefore determined oxygen supply parameters in RV tissue slices of deceased PAH patients and compared them with RV tissue of patients who died from left ventricular myocardial infarction (MI). Because autopsy tissue only reflects end-stage disease, rat models with stable and progressive pulmonary hypertension (PH) were studied as well. Methods: Myocardial tissue of 10 PAH and 10 MI patients was collected at autopsy. In rats, stable PH (n = 6) and progressive PH (n = 6) was induced by 40 or 60 mg/kg monocrotaline, respectively. Six rats were used as controls. Results: RV cardiomyocyte cross-sectional area was strongly increased in PAH compared with MI patients (p < 0.001), whereas capillary density decreased (p < 0.01). Rat data showed similar RV hypertrophy in stable and progressive PH, and RV capillary density was decreased in both (p < 0.01 and p < 0.0001 vs control rats, respectively). RV myoglobin protein content and functional concentration were reduced in both human and rat PH RVs. In rats, this results from a lack of increase in myoglobin mRNA transcription per cardiomyocyte nucleus. Conclusions: All measured cellular oxygen supply parameters are decreased in the failing human and rat pulmonary hypertensive RV. In contrast to stable PH rats, compensatory adaptations do not occur in end-stage PAH, despite higher myocardial oxygen consumption. © 2013 International Society for Heart and Lung Transplantation. Source

Alders D.J.C.,VU University Amsterdam | Alders D.J.C.,Institute for Cardiovascular Research | Johan Groeneveld A.B.,VU University Amsterdam | Binsl T.W.,Center for Integrative Bioinformatics | And 2 more authors.
American Journal of Physiology - Heart and Circulatory Physiology | Year: 2011

Heterogeneity of regional coronary blood flow is caused in part by heterogeneity in O 2 demand in the normal heart. We investigated whether myocardial O 2 supply/ demand mismatching is associated with the myocardial depression of sepsis. Regional blood flow (microspheres) and O 2 uptake ([ 13C] acetate infusion and analysis of resultant NMR spectra) were measured in about nine contiguous tissue samples from the left ventricle (LV) in each heart. Endotoxemic pigs (n = 9) showed hypotension at unchanged cardiac output with a fall in LV stroke work and first derivative of LV pressure relative to controls (n = 4). Global coronary blood flow and O 2 delivery were maintained. Lactate accumulated in arterial blood, but net lactate extraction across the coronary bed was unchanged during endotoxemia. When LV O 2 uptake based on blood gas versus NMR data were compared, the correlation was 0.73 (P = 0.007). While stable over time in controls, regional blood flows were strongly redistributed during endotoxin shock, with overall flow heterogeneity unchanged. A stronger redistribution of blood flow with endotoxin was associated with a larger fall in LV function parameters. Moreover, the correlation of regional O 2 delivery to uptake fell from r = 0.73 (P<0.001) in control to r = 0.18 (P = 0.25, P = 0.009 vs. control) in endotoxemic hearts. The results suggest a redistribution of LV regional coronary blood flow during endotoxin shock in pigs, with regional O 2 delivery mismatched to O 2 demand. Mismatching may underlie, at least in part, the myocardial depression of sepsis. © 2011 the American Physiological Society. Source

Schulkens I.A.,Angiogenesis Laboratory | Castricum K.C.M.,Angiogenesis Laboratory | Weijers E.M.,Institute for Cardiovascular Research | Koolwijk P.,Institute for Cardiovascular Research | And 3 more authors.
Journal of Vascular Research | Year: 2014

Metallothioneins (MTs) are small cysteine-rich proteins which are involved in e.g. metal homeostasis, metal detoxification and protection against oxidative stress. In addition, several MTs have been shown to regulate expression of proangiogenic growth factors like vascular endothelial growth factor. Detailed information about the expression and regulation of specific MT isoforms in endothelial cells (EC) is limited. We therefore performed extensive mRNA expression profiling of all known human MTs in EC. We found that the basal endothelial expression is restricted to MT1E, MT1X, MT2A, and MT3. Physiological activation of EC by exposure to serum increased the expression of MT1E and MT2A and induced the expression of MT1M. Furthermore, exposure to zinc or copper induced the expression of most MT1 isoforms, while hypoxia specifically increased the expression of MT1E, MT1M, MT1X, and MT3. Finally, knockdown of the dominant MT isoform in EC, i.e. MT2A, resulted in decreased proliferation and sprouting as well as in increased migration of human umbilical vein EC. Together, these findings provide a link between MTs and angiogenesis. © 2014 S. Karger AG, Basel. Source

den Hoedt C.H.,Maasstad Hospital | den Hoedt C.H.,University Utrecht | Bots M.L.,University Utrecht | Grooteman M.P.C.,Medical Center | And 10 more authors.
Clinical Journal of the American Society of Nephrology | Year: 2014

Background and objectives: Inflammation and malnutrition are important features in patients with ESRD; however, data on changes in these parameters over time are scarce. This study aimed to gain insight into changes over time in serum albumin, body mass index, high-sensitivity C-reactive protein, and IL-6 in patients with ESRD and aimed to identify clinical risk factors for deterioration of these parameters. Design, setting, participants, & measurements: Data were analyzed from the Convective Transport Study, a randomized controlled trial conducted from June 2004 to January 2011, in which 714 patients with chronic ESRD were randomized to either online hemodiafiltration or low-flux hemodialysis. Albumin and body mass index were measured up to 6 years and predialysis C-reactive protein and IL-6 were measured up to 3 years in a subset of 405 participants. Rates of change in these parameters over time were estimated across strata of predefined risk factors with linear mixed-effects models. Results: Albumin and body mass index decreased and C-reactive protein and IL-6 increased over time. For every incremental year of age at baseline, the yearly excess decline in albumin was 0.003 g/dl (-0.004 to -0.002; P<0.001) and the excess decline in body mass index was 0.02 kg/m2 per year (-0.02 to -0.01; P<0.001). In patients with diabetes mellitus, there was a yearly excess decline of 0.05 g/dl in albumin (-0.09 to -0.02; P=0.002). Compared with women, men had an excess decline of 0.03 g/dl per year in albumin (-0.06 to -0.001; P=0.05) and an excess increase of 11.6% per year in IL-6 (0.63%-23.6%; P=0.04). Conclusions: Despite guideline-based care, all inflammatory and nutritional parameters worsened over time. The deterioration of some of these parameters was more pronounced in men, older patients, and patients with diabetes mellitus. Special focus on the nutritional status of at-risk patients by individualizing medical care might improve their prognosis. © 2014 by the American Society of Nephrology. Source

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