68,206 research outputs found

    Assessment of respiratory flow cycle morphology in patients with chronic heart failure

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    Breathing pattern as periodic breathing (PB) in chronic heart failure (CHF) is associated with poor prognosis and high mortality risk. This work investigates the significance of a number of time domain parameters for characterizing respiratory flow cycle morphology in patients with CHF. Thus, our primary goal is to detect PB pattern and identify patients at higher risk. In addition, differences in respiratory flow cycle morphology between CHF patients (with and without PB) and healthy subjects are studied. Differences between these parameters are assessed by investigating the following three classification issues: CHF patients with PB versus with non-periodic breathing (nPB), CHF patients (both PB and nPB) versus healthy subjects, and nPB patients versus healthy subjects. Twenty-six CHF patients (8/18 with PB/nPB) and 35 healthy subjects are studied. The results show that the maximal expiratory flow interval is shorter and with lower dispersion in CHF patients than in healthy subjects. The flow slopes are much steeper in CHF patients, especially for PB. Both inspiration and expiration durations are reduced in CHF patients, mostly for PB. Using the classification and regression tree technique, the most discriminant parameters are selected. For signals shorter than 1 min, the time domain parameters produce better results than the spectral parameters, with accuracies for each classification of 82/78, 89/85, and 91/89 %, respectively. It is concluded that morphologic analysis in the time domain is useful, especially when short signals are analyzed.Peer ReviewedPostprint (author's final draft

    Vitamin C inhibits endothelial cell apoptosis in congestive heart failure

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    Background - Proinflammatory cytokines like tumor necrosis factor- and oxidative stress induce apoptotic cell death in endothelial cells (ECs). Systemic inflammation and increased oxidative stress in congestive heart failure (CHF) coincide with enhanced EC apoptosis and the development of endothelial dysfunction. Therefore, we investigated the effects of antioxidative vitamin C therapy on EC apoptosis in CHF patients. Methods and Results - Vitamin C dose dependently suppressed the induction of EC apoptosis by tumor necrosis factor- and angiotensin II in vitro as assessed by DNA fragmentation, DAPI nuclear staining, and MTT viability assay. The antiapoptotic effect of vitamin C was associated with reduced cytochrome C release from mitochondria and the inhibition of caspase-9 activity. To assess EC protection by vitamin C in CHF patients, we prospectively randomized CHF patients in a double-blind trial to vitamin C treatment versus placebo. Vitamin C administration to CHF patients markedly reduced plasma levels of circulating apoptotic microparticles to 32±8% of baseline levels, whereas placebo had no effect (87±14%, P<0.005). In addition, vitamin C administration suppressed the proapoptotic activity on EC of the serum of CHF patients (P<0.001). Conclusions - Administration of vitamin C to CHF patients suppresses EC apoptosis in vivo, which might contribute to the established functional benefit of vitamin C supplementation on endothelial function

    The Relationship between Nocturnal Hypoxemia and Left Ventricular Ejection Fraction in Congestive Heart Failure Patients

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    Background: sleep – disordered breathing ( SDB) is Frequently observed in Patients with Congestive heart Failure. This Study examines the Prevalence of sleep disorder in stable heart failure Patients regardless of ejection Fraction. Method: By Means of echocardiography 108 Patients with Left ventricular ejection Fraction ≤ 45% Were divided into Mild CHF, Moderate CHF and sever CHF. Hypoxemia was Recorded For 1 nights in the hospital was measure by Pulsoximetry. Resalts: In the 108 Patients with CHF, 44 ( 40/7%) had sever CHF, 17 ( 15/7%) moderote CHF 47( 43/6%) Mild CHF. 95 (% 88) of Patients with CHF has abnormal Petterns of nocturnal desaturation Suggestive of cheynestkes respiration. Ejecion Fraction Correlated negatively with dip freqnency. There was no correlation between Desaturation with BMI and snoring. Conclusion: This Study Confirm Strong associations between Sleep apnea and heart disease in Patients with CHF. Low Ejection Fraction Was related to dip frequency. These data suggest that People with congestive heart Failure Should be regarded as a risk group for sleep Apnea

    Levels of von Willebrand factor antigen and von Willebrand factor cleaving protease (ADAMTS13) activity predict clinical events in chronic heart failure.

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    Decreased activity of ADAMTS13, the von Willebrand factor (VWF) cleaving protease, was recently reported in cardiovascular diseases and in hepatic failure. Chronic heart failure (CHF) is characterised by abnormalities of left ventricular function accompanied by the failure of the liver and dysregulation of endothelial activation. Therefore, the aim of our study was to measure ADAMTS13 activity in CHF, and determine the prognostic value of VWF and ADAMTS13 on major clinical events in CHF. ADAMTS13 activity (measured by FRETS-VWF73 substrate) was decreased in CHF (n = 152, left ventricular ejection fraction <45%), and it correlated negatively with B-type natriuretic peptide (BNP) NYHA (New York Heart Association) classes, markers of synthetic capacity of the liver and endothelial dysfunction (all p < 0.005). Both, high VWF:Ag levels (hazard ratio [HR] 1.52, 95% confidence interval [CI] 1.189-1.943), and low ADAMTS13/VWF:Ag ratios (HR 0.70, 95% CI 0.58-0.84) independently and significantly predicted short-term (1 year follow-up) clinical adverse events in heart failure (HF). Decreased activity of ADAMTS13 with concomitant high VWF:Ag levels is a significant independent predictor of clinical events in CHF. The levels of the two molecules may integrate the impaired synthetic capacity of the liver and the disturbed endothelial regulation and can therefore be a useful tool to predict clinical events in CHF

    Longitudinal Analysis of Quality of Life, Clinical, Radiographic, Echocardiographic, and Laboratory Variables in Dogs with Preclinical Myxomatous Mitral Valve Disease Receiving Pimobendan or Placebo: The EPIC Study

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    Background: Changes in clinical variables associated with the administration of pimobendan to dogs with preclinical myxomatous mitral valve disease (MMVD) and cardiomegaly have not been described. Objectives: To investigate the effect of pimobendan on clinical variables and the relationship between a change in heart size and the time to congestive heart failure (CHF) or cardiac-related death (CRD) in dogs with MMVD and cardiomegaly. To determine whether pimobendan-treated dogs differ from dogs receiving placebo at onset of CHF. Animals: Three hundred and fifty-four dogs with MMVD and cardiomegaly. Materials and Methods: Prospective, blinded study with dogs randomized (ratio 1:1) to pimobendan (0.4-0.6 mg/kg/d) or placebo. Clinical, laboratory, and heart-size variables in both groups were measured and compared at different time points (day 35 and onset of CHF) and over the study duration. Relationships between short-term changes in echocardiographic variables and time to CHF or CRD were explored. Results: At day 35, heart size had reduced in the pimobendan group:median change in (Delta) LVIDDN -0.06 (IQR:-0.15 to + 0.02), P < 0.0001, and LA:Ao -0.08 (IQR:-0.23 to + 0.03), P < 0.0001. Reduction in heart size was associated with increased time to CHF or CRD. Hazard ratio for a 0.1 increase in Delta LVIDDN was 1.26, P = 0.0003. Hazard ratio for a 0.1 increase in Delta LA:Ao was 1.14, P = 0.0002. At onset of CHF, groups were similar. Conclusions and Clinical Importance: Pimobendan treatment reduces heart size. Reduced heart size is associated with improved outcome. At the onset of CHF, dogs treated with pimobendan were indistinguishable from those receiving placebo

    Congestive heart failure in rats is associated with increased expression and targeting of aquaporin-2 water channel in collecting duct

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    We tested whether severe congestive heart failure (CHF), a condition associated with excess free-water retention, is accompanied by altered regulation of the vasopressin-regulated water channel, aquaporin-2 (AQP2), in the renal collecting duct. CHF was induced by left coronary artery ligation. Compared with sham-operated animals, rats with CHF had severe heart failure with elevated left ventricular end-diastolic pressures (LVEDP): 26.9 ± 3.4 vs. 4.1 ± 0.3 mmHg, and reduced plasma sodium concentrations (142.2 ± 1.6 vs. 149.1 ± 1.1 mEq/liter). Quantitative immunoblotting of total kidney membrane fractions revealed a significant increase in AQP2 expression in animals with CHF (267 ± 53%, n=12) relative to sham-operated controls (100 ± 13%, n=14). In contrast, immunoblotting demonstrated a lack of an increase in expression of AQP1 and AQP3 water channel expression, indicating that the effect on AQP2 was selective.Furthermore, postinfarction animals without LVEDP elevation or plasma Na reduction showed no increase in AQP2 expression (121 ± 28% of sham levels, n=6). Immunocytochemistry and immunoelectron microscopy demonstrated very abundant labeling of the apical plasma membrane and relatively little labeling of intracellular vesicles in collecting duct cells from rats with severe CHF, consistent with enhanced trafficking of AQP2 to the apical plasma membrane. The selective increase in AQP2 expression and enhanced plasma membrane targeting provide an explanation for the development of water retention and hyponatremia in severe CHF

    Willingness to Pay for Community Health Fund Card in Mtwara Rural District,Tanzania

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    \ud The Ministry of Health in Tanzania has established a new programme in the primary health care service. CHF is a district-level prepayment scheme targeted at the rural population.CHF starts in 1995 on a pilot basis in one district and in 2003 has to be implemented in all districts. Mtwara Rural District is in the implantation stage. This study was proposed for assisting the district in pricing the health service and developing recommendations for the process of CHF implementation. It is focused primarily on the willingness of the population to pay for a CHF card.Price is not the only factor related to willingness to join the CHF. Complex human behavior,choices and motivation can also determine it. The result of the survey have drawn up the demand curve and constructed the chart of expected revenues from CHF card. Next stage was estimating the health Facility costs in order to find out the amount of funds to be collected. The CHF card rates proposed are based in maximizing the population under the health care system and covering the HF costs. The questionnaire prepared for the survey includes a section to know the opinion of respondents about the quality of care provided by MoH health facilities. According to the data obtained, the study proposed to establish the Tanzania national drug programme(Indent System),before CHF. Indent System changes the drug supply system and might improve the health quality. Experiences in Africa countries are also reviewed. This section contents the constraints identifies in other studies about different systems of payment. Evidence demonstrates the dangers associated with charging clients at the point of use of health service. Almost invariably payment systems have the affect of dissuading the poor from ccessing this services. Exemption mechanisms attempting to mitigate this impact have not tended to work. The experiences suggests querying some issues about CHF. The study is addressed to two audiences , MRD and MSF. This factor made complex drawing up the document. It was prepared with a view to: Pricing the health care services ,Developing recommendations for the CHF implementation in MRD and Providing qualitative information about the side effects of payment systems in the health care sector.\u

    Plasma Leptin Levels and Incidence of Heart Failure, Cardiovascular Disease, and Total Mortality in Elderly Individuals

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    OBJECTIVE: Obesity predisposes individuals to congestive heart failure (CHF) and cardiovascular disease (CVD). Leptin regulates energy homeostasis, is elevated in obesity, and influences ventricular and vascular remodeling. We tested the hypothesis that leptin levels are associated with greater risk of CHF, CVD, and mortality in elderly individuals. RESEARCH DESIGN AND METHODS: We evaluated 818 elderly (mean age 79 years, 62% women) Framingham Study participants attending a routine examination at which plasma leptin was assayed. RESULTS: Leptin levels were higher in women and strongly correlated with BMI (P < 0.0001). On follow-up (mean 8.0 years), 129 (of 775 free of CHF) participants developed CHF, 187 (of 532 free of CVD) experienced a first CVD event, and 391 individuals died. In multivariable Cox regression models adjusting for established risk factors, log-leptin was positively associated with incidence of CHF and CVD (hazard ratio [HR] per SD increment 1.26 [95% CI 1.03–1.55] and 1.28 [1.09–1.50], respectively). Additional adjustment for BMI nullified the association with CHF (0.97 [0.75–1.24]) but only modestly attenuated the relation to CVD incidence (1.23 [1.00–1.51], P = 0.052). We observed a nonlinear, U-shaped relation between log-leptin and mortality (P = 0.005 for quadratic term) with greater risk of death evident at both low and high leptin levels. CONCLUSIONS: In our moderate-sized community-based elderly sample, higher circulating leptin levels were associated with a greater risk of CHF and CVD, but leptin did not provide incremental prognostic information beyond BMI. Additional investigations are warranted to elucidate the U-shaped relation of leptin to mortality.National Institutes of Health's National Heart, Lung, and Blood Institute (N01-HC25195, N01-HV28178, K24-HL04334, R01-DK080739

    A qualitative study of the contribution of pharmacists to heart failure management in Scotland

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    Study objectives: (1) To identify the medication management needs of chronic heart failure (CHF) patients and their caregivers; (2) To examine the perceived support for medication management available to these people from health professionals; (3) To identify the actual and potential perceived contribution of pharmacists to medication management. Setting: A mixed urban/ rural region in the west of Scotland. Design: Semi-structured qualitative research interviews. Participants: A total of 50 people with CHF (NYHA Class II and III) due to left ventricular systolic dysfunction (33 males; mean age 67 years, 17 females; mean age 68 years) and 30 nominated caregivers recruited from the outpatient departments of two hospitals in the West of Scotland. Sampling was purposive to include patients from a range of CHF severity, ages and sexes. Main results: Managing medications was a responsibility shared by both the patients with CHF and caregivers. Treatment regimens were reported to be difficult to comply with. Health professionals were seen to provide little support for medication management. Pharmacists were viewed as being a good and accessible source of practical assistance who were also knowledgeable about the individual’s heart health history. Participants reported valuing advice from pharmacists about the side effects of medications and for their assistance in reducing the complex logistics of medication management and in having medications delivered. Conclusions: Patients with CHF and caregivers voiced a willingness to try to manage their medication regimen accurately but had a limited capacity to do so. Pharmacists were viewed as providing valuable support to patients with CHF and their caregivers, in terms of medication management. The extended role of pharmacists in medication management of CHF should be encouraged

    Threshold photoelectron photoion coincidence spectroscopy and selected ion flow tube reactions of CHF3: comparison of product branching ratios

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    The threshold photoelectron and threshold photoelectron photoion coincidence spectra of CHF3_3 in the range 13.5 – 24.5 eV have been recorded. Ion yields and branching ratios have been determined for the three fragments CF3+_3^+, CHF2+^+ and CF+^+. The mean kinetic energy releases into fragment ions involving either C-H or C-F bond cleavage have been measured, and compared with statistical and impulsive models. CHF3+_3^+ behaves in a non-statistical manner characteristic of the small-molecule limit, with the ground electronic state and low-lying excited states of CHF3+_3^+ being largely repulsive along the C-H and C-F coordinates, respectively. The rate coefficients and product ion branching ratios have been measured at 298 K in a selected ion flow tube for the reactions of CHF3_3 with a large number of gas-phase cations whose recombination energies span the range 6.3 through 21.6 eV. A comparison between the branching ratios from the two experiments, together with an analysis of the threshold photoelectron spectrum of CHF3_3, shows that long-range charge transfer probably occurs for the Ar+^+ and F+^+ atomic ions whose recombination energies lie above ca. 15 eV. Below this energy, the mechanism involves a combination of short-range charge transfer and chemical reactions involving a transition state intermediate
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