974 resultados para Cardiac-function


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Background: Sudden unexpected cardiac death (SUCD) accounts for approximately 25% of deaths from ischaemic heart disease (IHD) but is relatively poorly understood because of the difficulties involved in researching aetiology. Clinical differences between instances of SUCD and those cases of acute chest pain that survive long enough to be proven as myocardial infarction but are eventually fatal might reflect differences in aetiology. Aims: To determine the risk factors for sudden unexpected cardiac death in Tasmanian men. Methods: A population-based case-control method was used with the study population, an estimated 125,225 men aged 25-74 years living in the island State of Tasmania, Australia. The case group of 102 men who had a SUCD was validated using necropsy reports, hospital records and information provided by the usual general practitioner. Cases were matched with 204 community controls. Spouses or partners of eligible subjects answered a detailed questionnaire. Multi-variate odds ratios (ORs) for risk factors were calculated using stepwise analysis. Results: Risk factors measured included: smoking habit, treated hypertension, hypercholesterolaemia, diabetes mellitus, family history of LHD, alcohol intake and exercise habits. Independent risk factors for SUCD were: history of diabetes mellitus (OR=4.2, 95% CI: 1.39, 12.81), current smoking status (OR=3.5, 95% CI: 1.80, 6.82), and family history of IHD (OR=2.6, 95% CI: 1.34, 4.92). Conclusions: Some accepted risk factors for acute myocardial infarction (AMI) also predict sudden death in men with no history of coronary disease. Efforts to reduce smoking, the incidence of diabetes mellitus and mean blood pressure must be continued as SUCD is, by definition, untreatable but is potentially avoidable in many instances.

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Obesity is associated with increased sympathetic activity and higher mortality. Treatment of this condition is often frustrating. Roux-en-Y gastric bypass is the most effective technique nowadays for treatment of obesity. The aim of the present study is to assess the effects of this surgery on the cardiac autonomic activity, including the influence of gender and age, through heart rate variability (HRV) analysis. The study group consisted of 71 obese patients undergoing gastric bypass. Time domain measures of HRV, obtained from 24-h Holter recordings, were evaluated before and 6 months after surgery, and the results were compared. Percentage of interval differences of successive normal sinus beats greater than 50 ms (pNN50) and square root of the mean squared differences of successive normal sinus beat intervals (rMSSD) was used to estimate the short-term components of HRV, related to the parasympathetic activity. Standard deviation of intervals between all normal sinus beats (SDNN) was related to overall HRV. SDNN, pNN50, and rMSSD showed significant increase 6 months after surgery (p < 0.001, p = 0.001 and p = 0.002, respectively). Men presented a greater increase of SDNN than women (p = 0.006) during the follow-up. There was a difference in rMSSD evolution for age groups (p = 0.002). Only younger patients presented significant increase of rMSSD. Overall HRV increased 6 months after surgery; this increase was more evident in men. Cardiac parasympathetic activity increased also, but in younger patients only.

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Objective. To assess the testicular Sertoli cell function in male SLE patients. Methods. Thirty-four consecutive patients were prospectively selected to evaluate serum inhibin B. Clinical features, treatment, semen analysis, urological evaluation, testicular ultrasound, hormones and anti-sperm antibodies were determined. Results. Patients were subdivided into two groups: low serum inhibin B (Group 1, n = 8) and normal levels (Group 2, n 26). The median sperm concentration (P = 0.024), total sperm count (P = 0.023) and total motile sperm count (P = 0.025) were lower in Group 1. Inhibin B levels were positively correlated with sperm concentration (r = 0.343), total motile sperm count (r = 0.357), and negatively correlated with follicule-stimulating hormone (FSH) (r = 0.699) and luteinizing hormone (r = 0.397). The median serum inhibin B was lower in SLE patients treated with intravenous cyclophosphamide (IVCYC) compared with those without this therapy (P = 0.031). Further evaluation of the 26 SLE patients with normal inhibin B and FSH levels revealed that medians of inhibin B/FSH ratio were lower in SLE patients with oligozoospermia compared with normozoospermia (P = 0.004). This ratio was also lower in SLE patients treated with IVCYC than those without this therapy (P = 0.04). In contrast, inhibin B serum level alone did not discriminate the later group of patients (P = 0.12). Conclusions. This is the first study to identify a high frequency of testicular Sertoli cell dysfunction in male SLE associated with semen abnormalities. Further prospective studies are necessary to determine if inhibin levels and inhibin B/FSH ratio will be an earlier and useful marker of IVCYC toxicity in these patients.

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A number of studies conducted in humans and in animals have observed that events occurring early in life are associated with the development of diseases in adulthood. Salt overload and restriction during pregnancy and lactation are responsible for functional (hemodynamic and hormonal) and structural alterations in adult offspring. Our group observed that lower birth weight and insulin resistance in adulthood is associated with salt restriction during pregnancy On the other hand, perinatal salt overload is associated with higher blood pressure and higher renal angiotensin II content in adult offspring. Therefore, we hypothesised that renin-angiotensin system (RAS) function is altered by changes in sodium intake during pregnancy. Such changes may influence fetoplacental blood flow and thereby fetal nutrient supply, with effects on growth in utero and, consequently, on birth weight. Female Wistar rats were fed low-salt (LS), normal-salt (NS), or high-salt (HS) diet, starting before conception and continuing until day 19 of pregnancy, Blood pressure, heart rate, fetuses and dams` body weight, placentae weight and litter size were measured on day 19 of pregnancy. Cardiac output, uterine and placental blood flow were also determined on day 19. Expressions of renin-angiotensin system components and of the TNF-alpha gene were evaluated in the placentae. Plasma renin activity (PRA) and plasma and tissue angiotensin-converting enzyme (ACE) activity, as well as plasma and placental levels of angiotensins I, II, and 1-7 were measured. Body weight and kidney mass were greater in HS than in NS and LS dams. Food intake did not differ among the maternal groups. Placental weight was lower in LS dams than in NS and HS dams. Fetal weight was lower in the US group than in the NS and HS groups. The PRA was greater in IS dams than in NS and HS dams, although ACE activity (serum, cardiac, renal, and placental) was unaffected by the level of sodium intake. Placental levels of angiotensins I and II were lower in the HS group than in the ISIS and IS groups. Placental angiotensin receptor type 1 (AT(1)) gene expression and levels of thiobarbituric acid reactive substances (TBARS) were higher in HS dams, as were uterine blood flow and cardiac output. The degree of salt intake did not influence plasma sodium, potassium or creatinine. Although fractional sodium excretion was higher in HS dams than in NS and LS dams, fractional potassium excretion was unchanged. In conclusion, findings from this study indicate that the reduction in fetal weight in response to salt restriction during pregnancy does not involve alterations in uterine-placental perfusion or the RAS. Moreover, no change in fetal weight is observed in response to salt overload during pregnancy. However, salt overload did lead to an increase in placental weight and uterine blood flow associated with alterations in maternal plasma and placental RAS. Therefore, these findings indicate that changes in salt intake during pregnancy lead to alterations in uterine-placental perfusion and fetal growth. (C) 2008 Elsevier Inc. All rights reserved.

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The level of fractional exhaled nitric oxide (FENO) is significantly elevated in uncontrolled asthma and decreases after anti-inflammatory therapy The aim of this prospective study was to analyze the behavior of FENO in the follow-up and management of the inflammation in asthmatic pediatric patients treated with inhaled corticosteroids (ICS), compared to sputum cellularity, serum interleukins (IL), and pulmonary function. Twenty-six clinically stable asthmatic children aged from 6 to 18 years, previously treated or not with ICS were included. Following an international consensus (GINA), the patients were submitted to standard treatment with inhaled fluticasone for 3 months according to the severity of the disease. During this period, each patient underwent three assessments at intervals of approximately 6 weeks: Each evaluation consisted of the measurement of FENO, determination of serum interleukins IL-5, IL-10, IL-13, and interferon gamma (INF-gamma), spirometry and cytological analysis of spontaneous or induced sputum. A significant reduction in mean FENO and IL-5, without concomitant changes in FEV1, was observed along the study. There was no significant correlation between FeNO and FEV1 in the three assessments. A significant correlation between FeNO and IL-5 levels was only observed in the third assessment (r = 0.499, P=0.025). In most patients, serum IL-10, IL-13, and INF-gamma concentrations were undetectable throughout the study Sputum samples were obtained spontaneously in 11 occasions and in 56 by induction with 3% hypertonic saline solution (success rate: 50.8%), with 39 (69.9%) of them adequate for analysis. Only two of the 26 patients produced adequate samples in the three consecutive evaluations, which impaired the determination of a potential association between sputum cellularity and FeNO levels throughout the study. In conclusion, among the parameters of this study, it was difficult to perform and to interpret the serial analysis of spontaneous or induced sputum. Serum interleukins, which remained at very low or undetectable levels in most patients, were not found to be useful for therapeutic monitoring, except for IL-5 that seems to present some correlation with levels of FeNO exhaled. Monitoring of the mean FEV1 indicated no significant variations during the treatment, demonstrating that functional stability or the absence of obstruction may not reflect the adequate management of asthma. Serial measurement of FeNO seemed to best reflect the progressive anti-inflammatory action of ICS in asthma.

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Creatine supplementation may have a therapeutic role in diabetes, but it is uncertain whether this supplement is safe for kidney function. The aim of this study was to investigate the effects of creatine supplementation on kidney function in type 2 diabetic patients. A randomized, double-blind, placebo-controlled trial was performed. The patients were randomly allocated to receive either creatine or placebo for 12 weeks. All the patients underwent exercise training throughout the trial. Subjects were assessed at baseline and after the intervention. Blood samples and 24-h urine samples were obtained for kidney function assessments. Additionally, (51)Cr-EDTA clearance was performed. To ensure the compliance with creatine intake, we also assessed muscle phosphorylcreatine content. The creatine group presented higher muscle phosphorylcreatine content when compared to placebo group (CR Pre 44 +/- A 10, Post 70 +/- A 18 mmol/kg/wt; PL Pre 52 +/- A 13, Post 46 +/- A 13 mmol/kg/wt; p = 0.03; estimated difference between means 23.6; 95% confidence interval 1.42-45.8). No significant differences were observed for (51)Cr-EDTA clearance (CR Pre 90.4 +/- A 16.9, Post 96.1 +/- A 15.0 mL/min/1.73 m(2); PL Pre 97.9 +/- A 21.6, Post 96.4 +/- A 26.8 mL/min/1.73 m(2); p = 0.58; estimated difference between means -0.3; 95% confidence interval -24.9 to 24.2). Creatinine clearance, serum and urinary urea, electrolytes, proteinuria, and albuminuria were unchanged. CR supplementation does not affect kidney function in type 2 diabetic patients, opening a window of opportunities to explore its promising therapeutic role in this population. ClinicalTrials.gov registration number: NCT00992043.

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We examined the possibility that the heart of the turtle Chrysemys scripta is an exceptional anaerobic performer, by measuring myocardial power output, lactate output, and estimated ATP turnover in perfused heart preparations. Over a range of myocardial power outputs at 5 and 15 degrees C we find that turtle hearts perfused with anoxic saline do not show a particularly outstanding ability to produce ATP anaerobically. Furthermore, at 15 degrees C anoxia reduced the ATP turnover rate to 50% of the normoxic rate. At 5 degrees C the anoxia-induced depression of ATP turnover was even more pronounced, being 4-fold lower than the normoxic rate. In addition, anoxia at 5 degrees C reduced the basal metabolic rate of the turtle heart. We conclude that long-term cardiac tolerance of hypoxia in this species is more likely related to metabolic depression rather than to an exceptional anaerobic performance. (C) 1997 Elsevier Science Inc.

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Aims: To evaluate the presence of temporomandibular disorders (TMD) in systemic sclerosis (SSc) patients and its possible association with the severity of skin involvement. Methods: The presence of TMD was evaluated in 35 SSc women and 30 age- and sex-matched healthy controls by means of the anamnestic (A(i)) and clinical (D(i)) Helkimo indices; the jaw mobility was further analyzed (M(I)). Skin involvement was scored by the Modified Rodnan Skin Score (MRSS). Results: Signs and symptoms of TMD were more frequent in SSc patients than in controls, the frequency distribution of the different clinical dysfunction indices differing significantly (P < .001) between patients (D(i)0 8.6%, D(i)I 48.6%, D(i)II 22.8%, and D(i)III 20%) and controls (D(i)0 50%, D(i)I 33.3%, and D(i)II 16.7%). Cyclophosphamide for severe and rapidly progressive cutaneous fibrosis was prescribed in six out of seven patients with severe signs (D(i)III), in contrast this treatment was indicated for only two out of 25 patients with mild to moderate signs (D(i)I and D(i)II, P <. 001). Impaired jaw mobility was more frequent in SSc patients than controls (P < .001). It was severe in 77.1% (M(I)II) and mild in 22.9% (M(1)I) of the cases, in contrast to controls (M(I)0 33.4%, M(I)I 53.3%, and M(I)II 13.3%; P < .001). Approximately half of SSc patients with severe (M(I)II) but none of those with mild impairment were on cyclophosphamide treatment for severe cutaneous fibrosis (P = .02). Conclusion: Severe signs of TMD according to the anamnestic and clinical Helkimo indices were very frequent in SSc patients. J OROFAC PAIN 2010;24:197-202

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In type 2 diabetes (DM2) there is progressive deterioration in beta-cell function and mass. It was found that islet function was about 50% of normal at the time of diagnosis and reduction in beta-cell mass of about 60% at necropsy (accelerated apoptosis). Among the interventions to preserve the beta-cells, those to lead to short-term improvement of beta-cell secretion are weight loss, metformin, sulfonylureas, and insulin. The long-term improvement was demonstrated with short-term intensive insulin therapy of newly diagnosed DM2, the use of antiapoptotic drugs such as glitazones, and the use of glucagon-like peptide-1 receptor agonists (GLP-1 mimetics), not inactivated by the enzyme dipeptidyl peptidase 4 and/or to inhibit that enzyme (GLP-1 enhancers). The incretin hormones are released from the gastrointestinal tract in response to nutrient ingestion to enhance glucose-dependent insulin secretion from the pancreas and overall maintenance of glucose homeostasis. From the two major incretins, GLP-1 and GIP (glucose-dependent insulinotropic polypeptide), only the first one or its mimetics or enhancers can be used for treatment. The GLP-1 mimetics exenatide and liraglutide as well as the DPP4 inhibitors (sitagliptin and vildagliptin) were approved for treatment of DM2.

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Rheumatic fever (RF) is an autoimmune disease caused by the gram-positive bacteria Streptococcus pyogenes that follows a nontreated throat infection in susceptible children. The disease manifests as polyarthritis, carditis, chorea, erythema marginatum, and/or subcutaneous nodules. Carditis, the most serious complication, occurs in 30% to 45% of RF patients and leads to chronic rheumatic heart disease (RHD), which is characterized by progressive and permanent valvular lesions. In this review, we will focus on the genes that confer susceptibility for developing the disease, as well as the innate and adaptive immune responses against S. pyogenes during the acute rheumatic fever episode that leads to RHD autoimmune reactions. The disease is genetically determined, and some human leukocyte antigen class II alleles are involved with susceptibility. Other single nucleotide polymorphisms for TNF-alpha and mannan-binding lectin genes were reported as associated with RF/RHD. T cells play an important role in RHD heart lesions. Several autoantigens were already identified, including cardiac myosin epitopes, vimentin, and other intracellular proteins. In the heart tissue, antigen-driven oligoclonal T cell expansions were probably the effectors of the rheumatic heart lesions. These cells are CD4(+) and produced inflammatory cytokines (TNF alpha and IFN gamma). Molecular mimicry is the mechanism that mediated the cross-reactions between streptococcal antigens and human proteins. The elucidation of chemokines and their receptors involved with the recruitment of Th1, Th2, and Th17 cells, as well as the function of T regulatory cells in situ will certainly contribute to the delineation of the real picture of the heart lesion process that leads to RHD.

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Objective: To evaluate whether the number of vessels disease has an impact on clinical outcomes as well as on therapeutic results accordingly to medical, percutaneous, or surgery treatment in chronic coronary artery disease. Methods: We evaluated 825 individuals enrolled in MASS study, a randomized study to compare treatment options for single or multivessel coronary artery disease with preserved left ventricular function, prospectively followed during 5 years. The incidence of overall mortality and the composite end-point of death, myocardial infarction, and refractory angina were compared in three groups: single vessel disease (SVD n = 214), two-vessel disease (2VD n = 253) and three-vessel disease (3VD n = 358). The relationship between baseline variables and the composite end-point was assessed using a Cox proportional hazards survival model. Results: Most baseline characteristics were similar among groups, except age (younger in SVD and older in 3VD, p < 0.001), lower incidence of hypertension in SVD (p < 0.0001), and lower levels of total and LDL-cholesterol in 3VD (p = 0.004 and p = 0.005, respectively). There were no statistical differences in composite end-point in 5 years among groups independent of the kind of treatment; however, there was a higher mortality rate in 3VD (p < 0.001). When we stratified our analysis for each treatment option, bypass surgery was associated with a tower number of composite end-point in all groups (SVD p < 0.001, 2VD p = 0.002, 3VD p < 0.001). In multivariate analysis, we found higher mortality risk in 3VD comparing to SVD (p = 0.005, HR 3.14, 95%Cl 1.4-7.0). Conclusion: Three-vessel disease was associated with worse prognosis compared to single-or two-vessel disease in patients with stable coronary disease and preserved ventricular function at 5-year follow-up. In addition, event-free survival rates were higher after bypass surgery, independent of the number of vessels diseased in these subsets of patients. (c) 2008 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

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Objectives: To evaluate clinical and echocardiographic variables that could be used to predict outcomes in patients with asymptomatic severe aortic valve stenosis. Management of asymptomatic severe aortic stenosis is controversial. Because prophylactic surgery may be protective, independent predictors of events that could justify early surgery have been sought. Methods: Outpatients (n= 133; mean [+/- SD] age, 66.2 +/- 13.6 years) with isolated severe asymptomatic aortic stenosis but normal left ventricular function and no previous myocardial infarction were followed up prospectively at a tertiary care hospital. Interventions: We use a ""wait-for-events"" strategy. Clinical and echocardiographic variables were analyzed. Results: Nineteen patients developed angina; 40, dyspnea; 5, syncope; and 7, sudden death during a mean follow-up period of 3.30 +/- 1.87 years. Event-free survival was 90.2 +/- 2.6% at 1 year, 73.4 +/-.9% at 2 years, 70.7 +/- 4.3% at 3 years, 57.8 +/- 4.7% at 4 years, 40.3 +/- 5.0% at 5 years, and 33.3 +/- 5.2% at 6 years. The mean follow-up period until sudden death (1.32 +/- 1.11 years) was shorter than that for dyspnea (2.44 +/- 1.84 years), syncope (2.87 +/- 1.26 years) and angina (3.03 +/- 1.68 years). Cox regression analysis disclosed only reduced but within normal limits ejection fraction as independent predictor of total events. Conclusions: Management on ""wait-for-events"" strategy is generally safe. Progressive left ventricular ejection fraction reduction even within normal limits identified patients at high risk for events in whom valve replacement surgery should be considered. (c) 2007 Elsevier Ireland Ltd. All rights reserved.

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Background: Real time myocardial contrast echocardiography (RTMCE) is an emerging imaging modality for assessing myocardial perfusion that allows for noninvasive quantification of regional myocardial blood flow (MBF). Aim: We sought to assess the value of qualitative analysis of myocardial perfusion and quantitative assessment of myocardial blood flow (MBF) by RTMCE for predicting regional function recovery in patients with ischemic heart disease who underwent coronary artery bypass grafting (CABG). Methods: Twenty-four patients with coronary disease and left ventricular systolic dysfunction (ejection fraction < 45%) underwent RTMCE before and 3 months after CABG. RTMCE was performed using continuous intravenous infusion of commercially available contrast agent with low mechanical index power modulation imaging. Viability was defined by qualitative assessment of myocardial perfusion as homogenous opacification at rest in >= 2 segments of anterior or >= 1 segment of posterior territory. Viability by quantitative assessment of MBF was determined by receiver-operating characteristics curve analysis. Results: Regional function recovery was observed in 74% of territories considered viable by qualitative analysis of myocardial perfusion and 40% of nonviable (P = 0.03). Sensitivity, specificity, positive and negative predictive values of qualitative RTMCE for detecting regional function recovery were 74%, 60%, 77%, and 56%, respectively. Cutoff value of MBF for predicting regional function recovery was 1.76 (AUC = 0.77; 95% CI = 0.62-0.92). MBF obtained by RTMCE had sensitivity of 91%, specificity of 50%, positive predictive value of 75%, and negative predictive value of 78%. Conclusion: Qualitative and quantitative RTMCE provide good accuracy for predicting regional function recovery after CABG. Determination of MBF increases the sensitivity for detecting hibernating myocardium. (Echocardiography 2011;28:342-349).

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Introduction. Advantages of the bicaval versus the biatrial technique have been reported, emphasizing atrial electrical stability and less tricuspid regurgitation. Objective. To analyze the impact of the surgical technique on long-term pulmonary pressures, contractility, and graft valvular behavior after heart transplantation. Methods. Among 400 orthotopic heart transplantation recipients from 1985 to 2010, we selected 30 consecutive patients who had survived beyond 3 years. The biatrial versus bicaval surgical technique groups included 15 patients each. Their preoperative clinical characteristics were similar. None of the patients displayed a pulmonary vascular resistance or pulmonary artery pressure over 6U Wood or 60 mm Hg, respectively. We evaluated invasive hemodynamic parameters during routine endomyocardial biopsies. Two-dimensional echocardiographic parameters were obtained from routine examinations. Results. There were no significant differences regarding right atrial pressure, systolic pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, cardiac index, systolic blood pressure, left ventricular ejection fraction, and mitral regurgitation (P > .05). Tricuspid regurgitation increased significantly over the 3 years of observation only among the biatrial group (P = .0212). In both groups, the right atrial pressure, pulmonary wedge capillary pressure, transpulmonary gradient, and pulmonary vascular resistance decreased significantly (P < .05) from the pre- to the postoperative examination. In both groups cardiac index and systemic blood pressure increased significantly after transplantation (P < .05). Comparative analysis of the groups only showed significant differences regarding right atrial pressure and degree of tricuspid regurgitation; the bicaval group showing the best performance. Conclusions. Both surgical techniques ensure adequate left ventricular function in the long term; however, the bicaval technique provided better trends in hemodynamic performance, as well as a lower incidence and severity of tricuspid valve dysfunction.