374 resultados para Cardiac weight


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Although platelet cytosolic calcium has been shown to decrease during pharmacological treatment of hypertension, there is no evidence that cytosolic calcium also falls during a nonpharmacological reduction in blood pressure. To provide such evidence, we examined prospectively the relation between platelet cytosolic calcium and ambulatory blood pressure during weight reduction in moderately overweight (body mass index [BMI] greater than 25), mildly hypertensive individuals. The experimental group (responders: BMI reduction greater than 5%) consisted of 19 patients who lost 8.5 +/- 2.9 kg (mean +/- SD, p less than 0.05) during a 10-week hypocaloric diet, whereas the control group (nonresponders: BMI reduction less than 5%) consisted of 12 patients who showed no relevant change in body weight (-2.0 +/- 1.3 kg) during the same period of time. The moderate weight loss of the responders decreased blood pressure by 14/5 mm Hg (p less than 0.05), as measured by ambulatory monitoring, which renders a placebo effect unlikely. This nonpharmacological reduction in blood pressure was accompanied by a proportional 11% decrease (p less than 0.05) in platelet cytosolic calcium and also by significant (p less than 0.05) decreases in plasma catecholamines and serum cholesterol. These findings establish the concept of a nonpharmacological reduction in free cytosolic platelet calcium in humans and add further evidence suggesting a link between intracellular calcium homeostasis and blood pressure regulation.

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BACKGROUND: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited arrhythmia syndrome associated with mutations in the cardiac ryanodine receptor gene (Ryr2) in the majority of patients. Previous studies of CPVT patients mainly involved probands, so current insight into disease penetrance, expression, genotype-phenotype correlations, and arrhythmic event rates in relatives carrying the Ryr2 mutation is limited. METHODS AND RESULTS: One-hundred sixteen relatives carrying the Ryr2 mutation from 15 families who were identified by cascade screening of the Ryr2 mutation causing CPVT in the proband were clinically characterized, including 61 relatives from 1 family. Fifty-four of 108 antiarrhythmic drug-free relatives (50%) had a CPVT phenotype at the first cardiological examination, including 27 (25%) with nonsustained ventricular tachycardia. Relatives carrying a Ryr2 mutation in the C-terminal channel-forming domain showed an increased odds of nonsustained ventricular tachycardia (odds ratio, 4.1; 95% CI, 1.5-11.5; P=0.007, compared with N-terminal domain) compared with N-terminal domain. Sinus bradycardia was observed in 19% of relatives, whereas other supraventricular dysrhythmias were present in 16%. Ninety-eight (most actively treated) relatives (84%) were followed up for a median of 4.7 years (range, 0.3-19.0 years). During follow-up, 2 asymptomatic relatives experienced exercise-induced syncope. One relative was not being treated, whereas the other was noncompliant. None of the 116 relatives died of CPVT during a 6.7-year follow-up (range, 1.4-20.9 years). CONCLUSIONS: Relatives carrying an Ryr2 mutation show a marked phenotypic diversity. The vast majority do not have signs of supraventricular disease manifestations. Mutation location may be associated with severity of the phenotype. The arrhythmic event rate during follow-up was low.

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OBJECTIVE: To comprehensively assess pre-, intra-, and postoperative delirium risk factors as potential targets for intervention. BACKGROUND: Delirium after cardiac surgery is associated with longer intensive care unit (ICU) stay, and poorer functional and cognitive outcomes. Reports on delirium risk factors so far did not cover the full range of patients' presurgical conditions, intraoperative factors, and postoperative course. METHODS: After written informed consent, 221 consecutive patients ≥ 50 years scheduled for cardiac surgery were assessed for preoperative cognitive performance, and functional and physical status. Clinical and biochemical data were systematically recorded perioperatively. RESULTS: Of the 215 patients remaining for analysis, 31% developed delirium in the intensive care unit. Using logistic regression models, older age [73.3 (71.2-75.4) vs 68.5 (67.0-70.0); P = 0.016], higher Charlson's comorbidity index [3.0 (1.5-4.0) vs 2.0 (1.0-3.0) points; P = 0.009], lower Mini-Mental State Examination (MMSE) score (MMSE, [27 (23-29) vs 28 (27-30) points; P = 0.021], length of cardiopulmonary bypass (CPB) [CPB; 133 (112-163) vs 119 (99-143) min; P = 0.004], and systemic inflammatory response syndrome in the intensive care unit [25 (36.2%) vs 13 (8.9%); P = 0.001] were independently associated with delirium. Combining age, MMSE score, Charlson's comorbidity index, and length of CPB in a regression equation allowed for a prediction of postoperative delirium with a sensitivity of 71.19% and a specificity of 76.26% (receiver operating analysis, area under the curve: 0.791; 95% confidence interval: 0.727-0.845). CONCLUSIONS: Further research will evaluate if modification of these risk factors prevents delirium and improves outcomes.

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Saffaj et al. recently criticized our method of monitoring carbon dioxide in human postmortem cardiac gas samples using Headspace-Gas Chromatography-Mass Spectrometry. According to the authors, their demonstration, based on the latest SFSTP guidelines (established after 2007 [1,2]) fitted for the validation of drug monitoring bioanalytical methods, has put in evidence potential errors. However, our validation approach was built using SFSTP guidelines established before 2007 [3-6]. We justify the use of these guidelines because of the post-mortem context of the study (and not clinical) and the gaseous state of the sample (and not solid or liquid). Using these guidelines, our validation remains correct.

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Hereditary non-structural diseases such as catecholaminergic polymorphic ventricular tachycardia (CPVT), long QT, and the Brugada syndrome as well as structural disease such as hypertrophic cardiomyopathy (HCM) and arrhythmogenic right ventricular cardiomyopathy (ARVC) cause a significant percentage of sudden cardiac deaths in the young. In these cases, genetic testing can be useful and does not require proxy consent if it is carried out at the request of judicial authorities as part of a forensic death investigation. Mutations in several genes are implicated in arrhythmic syndromes, including SCN5A, KCNQ1, KCNH2, RyR2, and genes causing HCM. If the victim's test is positive, this information is important for relatives who might be themselves at risk of carrying the disease-causing mutation. There is no consensus about how professionals should proceed in this context. This article discusses the ethical and legal arguments in favour of and against three options: genetic testing of the deceased victim only; counselling of relatives before testing the victim; counselling restricted to relatives of victims who tested positive for mutations of serious and preventable diseases. Legal cases are mentioned that pertain to the duty of geneticists and other physicians to warn relatives. Although the claim for a legal duty is tenuous, recent publications and guidelines suggest that geneticists and others involved in the multidisciplinary approach of sudden death (SD) cases may, nevertheless, have an ethical duty to inform relatives of SD victims. Several practical problems remain pertaining to the costs of testing, the counselling and to the need to obtain permission of judicial authorities.

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Normal myocardium adapts to increase of nutritional fatty acid supply by upregulation of regulatory proteins of the fatty acid oxidation pathway. Because advanced heart failure is associated with reduction of regulatory proteins of fatty acid oxidation, we hypothesized that failing myocardium may not be able to adapt to increased fatty acid intake and therefore undergo lipid accumulation, potentially aggravating myocardial dysfunction. We determined the effect of high-fat diet in transgenic mice with overexpression of angiotensinogen in the myocardium (TG1306/R1). TG1306/R1 mice develop ANG II-mediated left ventricular hypertrophy, and at one year of age approximately half of the mice present heart failure associated with reduced expression of regulatory proteins of fatty acid oxidation and reduced palmitate oxidation during ex vivo working heart perfusion. Hypertrophied hearts from TG1306/R1 mice without heart failure adapted to high-fat feeding, similarly to hearts from wild-type mice, with upregulation of regulatory proteins of fatty acid oxidation and enhancement of palmitate oxidation. There was no myocardial lipid accumulation or contractile dysfunction. In contrast, hearts from TG1306/R1 mice presenting heart failure were unable to respond to high-fat feeding by upregulation of fatty acid oxidation proteins and enhancement of palmitate oxidation. This resulted in accumulation of triglycerides and ceramide in the myocardium, and aggravation of contractile dysfunction. In conclusion, hearts with ANG II-induced contractile failure have lost the ability to enhance fatty acid oxidation in response to increased fatty acid supply. The ensuing accumulation of lipid compounds may play a role in the observed aggravation of contractile dysfunction.

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OBJECTIVE. The purpose of our study was to evaluate hepatic, gastrointestinal, and cardiac toxicity after PRECISION transarterial chemoembolization (TACE) with drug-eluting beads (DEB) versus conventional TACE with doxorubicin in the treatment of intermediate-stage hepatocellular carcinoma (HCC).SUBJECTS AND METHODS. Two hundred twelve patients (185 men and 27 women; mean age, 67 years) were randomized to TACE with DEB or conventional TACE. The majority of patients (67% in both groups) presented in a more advanced stage. Safety was measured by rate of adverse events (Southwest Oncology Group criteria) and changes in laboratory parameters. Cardiotoxicity was assessed with left ventricular ejection fraction (LVEF) mainly on MRI or echocardiography.RESULTS. The mean maximum postchemoembolization alanine transaminase increase in the DEB group was 50% less than in the conventional TACE group (p < 0.001) and 41% less in respect to aspartate transaminase (p < 0.001). End-of-study values returned to approximately baseline levels but with greater variability in conventional TACE patients. Treatment-emergent adverse events in the hepatobiliary system organ class occurred in 16.1% of DEB group patients compared with 25% of conventional TACE patients. There were fewer liver toxicity events in the DEB group. There was a small but statistically significant difference in mean change from baseline in LVEF between the two groups of 4 percentage points for the conventional TACE group (95% CI, 0.71-7.3; p = 0.018).CONCLUSION. PRECISION TACE with DEB loaded with doxorubicin offers a safe therapy option for intermediate-stage HCC, even in patients with more advanced liver disease.

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Two new forms of non-specific crossreacting antigens (NCAs) were identified in the Nonidet P40 (NP-40) extracts of normal granulocytes by precipitation with the monoclonal antibody (MAb) 192 directed against carcinoembryonic antigen (CEA) and already known to crossreact with the perchloric acid soluble NCA-55. The NP-40 soluble NCAs recognized by MAb 192 have apparent mol. wts of 90,000 and 160,000 in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Both NCAs appear to consist of a single monomeric polypeptide chain, since they have the same electrophoretic mobility in SDS-PAGE under reduced and non-reduced conditions. When granulocytes were extracted with perchloric acid instead of NP-40, only the 55,000 mol. wt antigen, corresponding to the previously described NCA-55, was precipitated by MAb 192. Furthermore, it was shown that NCA-55 is not a degradation product of NCA-90 or NCA-160 due to the perchloric acid treatment because exposure to perchloric acid of NCA preparations purified from NP-40 extracts did not change their apparent mol. wts in SDS-PAGE. It was also shown that NCA-160 is not a granulocytic form of CEA because it was not precipitated by the MAb 35 reacting exclusively with CEA. Immunocytochemical studies of granulocytes and macrophages showed that MAb 192 stained both types of cells whereas MAb 47 stained only the granulocytes and MAb 35 none of these cells. In granulocytes both MAbs reacted with antigens associated with granules and also present at the periphery of the nucleus as well as in the Golgi apparatus. The NCA-90 identified by MAb 192 was found by sequential immunodepletion to be antigenically distinct from the NCA-95 precipitated by MAb 47. The epitope recognized by MAb 192 on CEA and NCA molecules appears to be on the peptidic moiety because the antigens deglycosylated by the enzyme Endo F were still precipitated by this MAb. Taken together, the results indicate that MAb 192 identifies two novel forms of NCA (NCA-90 and NCA-160) in NP-40 extracts of granulocytes, which are distinct from CEA and the previously described NCA-55 and NCA-95 identified by MAbs 192 and 47, respectively, in perchloric acid extracts of granulocytes.

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High aldehyde dehydrogenase (ALDH) activity has been associated with stem and progenitor cells in various tissues. Human cord blood and bone marrow ALDH-bright (ALDH(br)) cells have displayed angiogenic activity in preclinical studies and have been shown to be safe in clinical trials in patients with ischemic cardiovascular disease. The presence of ALDH(br) cells in the heart has not been evaluated so far. We have characterized ALDH(br) cells isolated from mouse hearts. One percent of nonmyocytic cells from neonatal and adult hearts were ALDH(br). ALDH(very-br) cells were more frequent in neonatal hearts than adult. ALDH(br) cells were more frequent in atria than ventricles. Expression of ALDH1A1 isozyme transcripts was highest in ALDH(very-br) cells, intermediate in ALDH(br) cells, and lowest in ALDH(dim) cells. ALDH1A2 expression was highest in ALDH(very-br) cells, intermediate in ALDH(dim) cells, and lowest in ALDH(br) cells. ALDH1A3 and ALDH2 expression was detectable in ALDH(very-br) and ALDH(br) cells, unlike ALDH(dim) cells, albeit at lower levels compared with ALDH1A1 and ALDH1A2. Freshly isolated ALDH(br) cells were enriched for cells expressing stem cell antigen-1, CD34, CD90, CD44, and CD106. ALDH(br) cells, unlike ALDH(dim) cells, could be grown in culture for more than 40 passages. They expressed sarcomeric α -actinin and could be differentiated along multiple mesenchymal lineages. However, the proportion of ALDH(br) cells declined with cell passage. In conclusion, the cardiac-derived ALDH(br) population is enriched for progenitor cells that exhibit mesenchymal progenitor-like characteristics and can be expanded in culture. The regenerative potential of cardiac-derived ALDH(br) cells remains to be evaluated.

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Controlling the extracellular volume in hemodialysis patients is a difficult task. The aim of this study was to evaluate the capacity of different methods of stimulated sweating to reduce mean interdialytic weight gain (IWG), to improve blood pressure regulation, and potassium/urea balance. Two center, crossover pilot study. In Lausanne, hemodialysis patients took four hot-water baths a week, 30 minutes each, on nondialysis days during 1 month. In Sfax, patients visited the local Hammam Center four times a week. Hemodynamic parameters were recorded, and weekly laboratory analysis was performed. Results were compared with a preceding 1-month control period. In Lausanne, five patients (all men, median age 55 years) participated. Bathing temperature was (mean ± standard deviation) 41.2 ± 3°C and sweating-induced weight loss 600 ± 500 g. Mean IWG (control vs. intervention period) decreased from 2.3 ± 0.9 to 1.8 ± 1 kg (P = 0.004), Systolic blood pressure from 139 ± 21 to 136 ± 22 mmHg (P = 0.4), and diastolic blood pressure form 79 ± 12 to 75 ± 13 mmHg (P = 0.08); antihypertensive therapy could be reduced from 2.8 ± 0.4 to 1.9 ± 0.5 antihypertensive drugs per patient (P = 0.01). In Sfax (n = 9, median age 46 years), weight loss per Hammam session was 420 ± 100 g. No differences were found in IWG or BP, but predialysis serum potassium level decreased from 5.9 ± 0.8 to 5.5 ± 0.9 mmol/L (P = 0.04) and urea from 26.9 ± 6 to 23.1 ± 6 mmol/L (P = 0.02). Hot-water baths appear to be a safe way to reduce IWG in selected hemodialysis patients. Hammam visits reduce serum potassium and urea levels, but not IWG. More data in larger patient groups are necessary before definite conclusion can be drawn.

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Devices for venous cannulation have seen significant progress over time: the original, rigid steel cannulas have evolved toward flexible plastic cannulas with wire support that prevents kinking, very thin walled wire wound cannulas allowing for percutaneous application, and all sorts of combinations. In contrast to all these rectilinear venous cannula designs, which present the same cross-sectional area over their entire intravascular path, the smartcanula concept of "collapsed insertion and expansion in situ" is the logical next step for venous access. Automatically adjusting cross-sectional area up to a pre-determined diameter or the vessel lumen provides optimal flow and ease of use for both, insertion and removal. Smartcanula performance was assessed in a small series of patients (76 +/- 17 kg) undergoing redo procedures. The calculated target pump flow (2.4 L/min/m2) was 4.42 +/- 61 L/ min. Mean pump flow achieved during cardiopulmonary bypass was 4.84 +/- 87 L/min or 110% of the target. Reduced atrial chatter, kink resistance in situ, and improved blood drainage despite smaller access orifice size, are the most striking advantages of this new device. The benefits of smart cannulation are obvious in remote cannulation for limited access cardiac surgery, but there are many other cannula applications where space is an issue, and that is where smart cannulation is most effective.

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We previously reported that excess of deoxycorticosterone-acetate (DOCA)/salt-induced cardiac hypertrophy in the absence of hypertension in one-renin gene mice. This model allows us to study molecular mechanisms of high-salt intake in the development of cardiovascular remodeling, independently of blood pressure in a high mineralocorticoid state. In this study, we compared the effect of 5-wk low- and high-salt intake on cardiovascular remodeling and cardiac differential gene expression in mice receiving the same amount of DOCA. Differential gene and protein expression was measured by high-density cDNA microarray assays, real-time PCR and Western blot analysis in DOCA-high salt (HS) vs. DOCA-low salt (LS) mice. DOCA-HS mice developed cardiac hypertrophy, coronary perivascular fibrosis, and left ventricular dysfunction. Differential gene and protein expression demonstrated that high-salt intake upregulated a subset of genes encoding for proteins involved in inflammation and extracellular matrix remodeling (e.g., Col3a1, Col1a2, Hmox1, and Lcn2). A major subset of downregulated genes encoded for transcription factors, including myeloid differentiation primary response (MyD) genes. Our data provide some evidence that vascular remodeling, fibrosis, and inflammation are important consequences of a high-salt intake in DOCA mice. Our study suggests that among the different pathogenic factors of cardiac and vascular remodeling, such as hypertension and mineralocorticoid excess and sodium intake, the latter is critical for the development of the profibrotic and proinflammatory phenotype observed in the heart of normotensive DOCA-treated mice.

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An active strain formulation for orthotropic constitutive laws arising in cardiac mechanics modeling is introduced and studied. The passive mechanical properties of the tissue are described by the Holzapfel-Ogden relation. In the active strain formulation, the Euler-Lagrange equations for minimizing the total energy are written in terms of active and passive deformation factors, where the active part is assumed to depend, at the cell level, on the electrodynamics and on the specific orientation of the cardiac cells. The well-posedness of the linear system derived from a generic Newton iteration of the original problem is analyzed and different mechanical activation functions are considered. In addition, the active strain formulation is compared with the classical active stress formulation from both numerical and modeling perspectives. Taylor-Hood and MINI finite elements are employed to discretize the mechanical problem. The results of several numerical experiments show that the proposed formulation is mathematically consistent and is able to represent the main key features of the phenomenon, while allowing savings in computational costs.