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Sample records for age ejection fraction

  1. Ejection Fraction Heart Failure Measurement

    MedlinePlus

    ... Thromboembolism Aortic Aneurysm More Ejection Fraction Heart Failure Measurement Updated:Feb 15,2017 The ejection fraction (EF) is an important measurement in determining how well your heart is pumping ...

  2. Ejection Fraction: What Does It Measure?

    MedlinePlus

    ... does the term "ejection fraction" mean? What does it measure? Answers from Rekha Mankad, M.D. Ejection fraction ... percentage of blood leaving your heart each time it contracts. During each heartbeat pumping cycle, the heart ...

  3. Application of the Age, Creatinine, and Left Ventricular Ejection Fraction Score for Patients on Extracorporeal Membrane Oxygenation.

    PubMed

    Tsai, Tsung-Yu; Tsai, Feng-Chun; Fan, Pei-Chun; Chang, Chih-Hsiang; Lin, Chan-Yu; Chang, Wei-Wen; Lee, Shen-Yang; Hsu, Hsiang-Hao; Tian, Ya-Chung; Fang, Ji-Tseng; Yang, Chih-Wei; Chen, Yung-Chang

    2017-02-01

    Patients on extracorporeal membrane oxygenation (ECMO) usually have high mortality rate and poor outcome. Age, Creatinine, and Left Ventricular Ejection Fraction (ACEF) score is an easy-calculating score and provides good performance on mortality prediction in patients undergoing cardiac operations or percutaneous coronary intervention, but it has not been applied to patients on ECMO before. In this study, we aimed to use ACEF score obtained within 1 week of ECMO support for in-hospital mortality prediction in patients on ECMO due to severe myocardial failure. This study reviewed the medical records of 306 patients on ECMO at a specialized intensive care unit (CVSICU) in a tertiary-care university hospital between March 2002 and December 2011, and 105 patients on veno-arterial ECMO due to severe myocardial failure were enrolled. Demographic, clinical, and laboratory variables were retrospectively collected as survival predictors. The overall mortality rate was 47.6%. The most frequent condition requiring ICU admission was postcardiotomy cardiogenic shock. Multiple logistic regression analysis indicated that post-ECMO ACEF score, Sequential Organ Failure Assessment score, and troponin I on day 1 of ECMO support were independent risk factors for in-hospital mortality. Using the area under the receiver operating characteristic curve (AUROC), the post-ECMO ACEF score indicated a good discriminative power (AUROC 0.801 ± 0.042). Finally, cumulative survival rates at 6-month follow-up differed significantly (P < 0.001) for an ACEF score ≤ 2.22 versus those with an ACEF score > 2.22. After ECMO treatment due to severe myocardial failure, post-ECMO ACEF score provides an easy-calculating method with a reproducible evaluation tool with excellent prognostic abilities in these patients.

  4. Effect of age and sex on efficacy and tolerability of β blockers in patients with heart failure with reduced ejection fraction: individual patient data meta-analysis

    PubMed Central

    Manzano, Luis; Krum, Henry; Rosano, Giuseppe; Holmes, Jane; Altman, Douglas G; Collins, Peter D; Packer, Milton; Wikstrand, John; Coats, Andrew J S; Cleland, John G F; Kirchhof, Paulus; von Lueder, Thomas G; Rigby, Alan S; Andersson, Bert; Lip, Gregory YH; van Veldhuisen, Dirk J; Shibata, Marcelo C; Wedel, Hans; Böhm, Michael; Flather, Marcus D

    2016-01-01

    Objectives To determine the efficacy and tolerability of β blockers in a broad age range of women and men with heart failure with reduced ejection fraction (HFrEF) by pooling individual patient data from placebo controlled randomised trials. Design Prospectively designed meta-analysis of individual patient data from patients aged 40-85 in sinus rhythm at baseline, with left ventricular ejection fraction <0.45. Participants 13 833 patients from 11 trials; median age 64; 24% women. Main outcome measures The primary outcome was all cause mortality; the major secondary outcome was admission to hospital for heart failure. Analysis was by intention to treat with an adjusted one stage Cox proportional hazards model. Results Compared with placebo, β blockers were effective in reducing mortality across all ages: hazard ratios were 0.66 (95% confidence interval 0.53 to 0.83) for the first quarter of age distribution (median age 50); 0.71 (0.58 to 0.87) for the second quarter (median age 60); 0.65 (0.53 to 0.78) for the third quarter (median age 68); and 0.77 (0.64 to 0.92) for the fourth quarter (median age 75). There was no significant interaction when age was modelled continuously (P=0.1), and the absolute reduction in mortality was 4.3% over a median follow-up of 1.3 years (number needed to treat 23). Admission to hospital for heart failure was significantly reduced by β blockers, although this effect was attenuated at older ages (interaction P=0.05). There was no evidence of an interaction between treatment effect and sex in any age group. Drug discontinuation was similar regardless of treatment allocation, age, or sex (14.4% in those give β blockers, 15.6% in those receiving placebo). Conclusion Irrespective of age or sex, patients with HFrEF in sinus rhythm should receive β blockers to reduce the risk of death and admission to hospital. Registration PROSPERO CRD42014010012; Clinicaltrials.gov NCT00832442. PMID:27098105

  5. Heart failure with preserved ejection fraction

    PubMed Central

    ElGuindy, Ahmed; Yacoub, Magdi H

    2012-01-01

    Abstract Heart failure with preserved ejection fraction (HFpEF) has recently emerged as a major cause of cardiovascular morbidity and mortality. Contrary to initial beliefs, HFpEF is now known to be as common as heart failure with reduced ejection fraction (HFrEF) and carries an unacceptably high mortality rate. With a prevalence that has been steadily rising over the past two decades, it is very likely that HFpEF will represent the dominant heart failure phenotype over the coming few years. The scarcity of trials in this semi-discrete form of heart failure and lack of unified enrolment criteria in the studies conducted to date might have contributed to the current absence of specific therapies. Understanding the epidemiological, pathophysiological and molecular differences (and similarities) between these two forms of heart failure is cornerstone to the development of targeted therapies. Carefully designed studies that adhere to unified diagnostic criteria with the recruitment of appropriate controls and adoption of practical end-points are urgently needed to help identify effective treatment strategies. PMID:25610841

  6. Is heart failure with midrange ejection fraction similar to preserved ejection fraction? Against.

    PubMed

    Formiga, F

    2017-03-14

    The new European guidelines (2016) for heart failure (HF) include the concept of HF with intermediate left ventricular ejection fraction (LVEF), i.e. an LVEF between 40 and 49%. Although few studies have been carried out, there are claims that HF with intermediate LVEF is not the same as HF with preserved LVEF. Perhaps the most consistent claim is the high percentage of associated ischemic heart disease, which could reflect LVEF recovery after adequate anti-ischemic treatment of HF with depressed LVEF, or even the progressive deterioration of LVEF following an ischemic event.

  7. Heart failure with preserved ejection fraction and skeletal muscle physiology.

    PubMed

    Farris, Stephen D; Moussavi-Harami, Farid; Stempien-Otero, April

    2017-03-01

    Heart failure with preserved ejection fraction (HFpEF) accounts for half of all heart failure in the USA, increases in prevalence with aging, and has no effective therapies. Intriguingly, the pathophysiology of HFpEF has many commonalities with the aged cardiovascular system including reductions in diastolic compliance, chronotropic defects, increased resistance in the peripheral vasculature, and poor energy substrate utilization. Decreased exercise capacity is a cardinal symptom of HFpEF. However, its severity is often out of proportion to changes in cardiac output. This observation has led to studies of muscle function in HFpEF revealing structural, biomechanical, and metabolic changes. These data, while incomplete, support a hypothesis that similar to aging, HFPEF is a systemic process. Understanding the mechanisms leading to exercise intolerance in this condition may lead to strategies to improve morbidity in both HFpEF and aging.

  8. Videodensitometric ejection fraction from intravenous digital subtraction right ventriculograms: correlation with first pass radionuclide ejection fraction

    SciTech Connect

    Detrano, R.; MacIntyre, W.; Salcedo, E.E.; O'Donnell, J.; Underwood, D.A.; Simpfendorfer, C.; Go, R.T.; Butters, K.; Withrow, S.

    1985-06-01

    Thirty-one consecutive patients undergoing intravenous blurred mask digital subtraction right ventriculography were submitted to first pass radionuclide angiography. Second order mask resubtraction of end-diastolic and end-systolic right ventricular digital image frames was executed using preinjection end-diastolic and end-systolic frames to rid the digital subtraction images of mis-registration artifact. End-diastolic and end-systolic perimeters were drawn manually by two independent observers with a light pen. Ejection fractions calculated from the integrated videodensitometric counts within these perimeters correlated well with those derived from the first pass radionuclide right ventriculogram (r = 0.84) and the interobserver correlation was acceptable (r = 0.91). Interobserver differences occurred more frequently in patients with atrial fibrillation and in those whose tricuspid valve planes were difficult to discern on the digital subtraction right ventriculograms. These results suggest that videodensitometric analysis of digital subtraction right ventriculograms is an accurate method of determining right ventricular ejection fraction and may find wide clinical applicability.

  9. Classification of Contextual Use of Left Ventricular Ejection Fraction Assessments.

    PubMed

    Kim, Youngjun; Garvin, Jennifer; Goldstein, Mary K; Meystre, Stéphane M

    2015-01-01

    Knowledge of the left ventricular ejection fraction is critical for the optimal care of patients with heart failure. When a document contains multiple ejection fraction assessments, accurate classification of their contextual use is necessary to filter out historical findings or recommendations and prioritize the assessments for selection of document level ejection fraction information. We present a natural language processing system that classifies the contextual use of both quantitative and qualitative left ventricular ejection fraction assessments in clinical narrative documents. We created support vector machine classifiers with a variety of features extracted from the target assessment, associated concepts, and document section information. The experimental results showed that our classifiers achieved good performance, reaching 95.6% F1-measure for quantitative assessments and 94.2% F1-measure for qualitative assessments in a five-fold cross-validation evaluation.

  10. Biomarkers of Heart Failure with Preserved and Reduced Ejection Fraction.

    PubMed

    Senni, Michele; D'Elia, Emilia; Emdin, Michele; Vergaro, Giuseppe

    2017-02-09

    Biomarkers are increaingly being used in the management of heart failure not only for the purpose of screening, diagnosis, and risk stratification, but also as a guide to evaluate the response to treatment in the individual patient and as an entry criterion and/or a surrogate marker of efficacy in clinical trials testing novel drugs. In this chapter, we review the role of established biomarkers for heart failure management, according to the main classification of HF phenotypes, based on the measurement of left ventricular ejection fraction, including heart failure with reduced (<40%), preserved (≥50%), and, as recently proposed, mid-range (40-49%) ejection fraction.

  11. Diagnosis of heart failure with preserved ejection fraction.

    PubMed

    Wachter, Rolf; Edelmann, Frank

    2014-07-01

    Heart failure with preserved ejection fraction (HFpEF) constitutes a growing health care burden worldwide. Although definitions vary somewhat among guidelines, in general the presence of typical heart failure symptoms and signs in combination with a preserved left ventricular ejection fraction (≥50%) and functional and/or structural left ventricular changes makes the diagnosis likely. This review focuses on the current understanding of diagnostic criteria, as presented in current guidelines and consensus recommendations, and on new insights from recent papers. The role of comorbidities that often contribute to symptoms and hamper the HFpEF diagnostics is also reviewed.

  12. Metabolomic Fingerprint of Heart Failure with Preserved Ejection Fraction

    PubMed Central

    Zordoky, Beshay N.; Sung, Miranda M.; Ezekowitz, Justin; Mandal, Rupasri; Han, Beomsoo; Bjorndahl, Trent C.; Bouatra, Souhaila; Anderson, Todd; Oudit, Gavin Y.; Wishart, David S.; Dyck, Jason R. B.

    2015-01-01

    Background Heart failure (HF) with preserved ejection fraction (HFpEF) is increasingly recognized as an important clinical entity. Preclinical studies have shown differences in the pathophysiology between HFpEF and HF with reduced ejection fraction (HFrEF). Therefore, we hypothesized that a systematic metabolomic analysis would reveal a novel metabolomic fingerprint of HFpEF that will help understand its pathophysiology and assist in establishing new biomarkers for its diagnosis. Methods and Results Ambulatory patients with clinical diagnosis of HFpEF (n = 24), HFrEF (n = 20), and age-matched non-HF controls (n = 38) were selected for metabolomic analysis as part of the Alberta HEART (Heart Failure Etiology and Analysis Research Team) project. 181 serum metabolites were quantified by LC-MS/MS and 1H-NMR spectroscopy. Compared to non-HF control, HFpEF patients demonstrated higher serum concentrations of acylcarnitines, carnitine, creatinine, betaine, and amino acids; and lower levels of phosphatidylcholines, lysophosphatidylcholines, and sphingomyelins. Medium and long-chain acylcarnitines and ketone bodies were higher in HFpEF than HFrEF patients. Using logistic regression, two panels of metabolites were identified that can separate HFpEF patients from both non-HF controls and HFrEF patients with area under the receiver operating characteristic (ROC) curves of 0.942 and 0.981, respectively. Conclusions The metabolomics approach employed in this study identified a unique metabolomic fingerprint of HFpEF that is distinct from that of HFrEF. This metabolomic fingerprint has been utilized to identify two novel panels of metabolites that can separate HFpEF patients from both non-HF controls and HFrEF patients. Clinical Trial Registration ClinicalTrials.gov NCT02052804 PMID:26010610

  13. Value of left ventricular ejection fraction during exercise in predicting the extent of coronary artery disease.

    PubMed

    DePace, N L; Iskandrian, A S; Hakki, A H; Kane, S A; Segal, B L

    1983-04-01

    To determine the relation between left ventricular performance during exercise and the extent of coronary artery disease, the results of exercise radionuclide ventriculography were analyzed in 65 patients who also underwent cardiac catheterization. A scoring system was used to quantitate the extent of coronary artery disease. This system takes into account the number and site of stenoses of the major coronary vessels and their secondary branches. The conventional method of interpreting the coronary angiograms indicated that 26 patients had significant coronary artery disease (defined as 70% or more narrowing of luminal diameter) of one vessel, 21 had multivessel disease and 18 had no significant coronary artery disease. Although the exercise left ventricular ejection fraction was significantly higher in patients with no coronary artery disease than in patients with one or multivessel disease (probability [p] less than 0.001), there was considerable overlap among the three groups. With the scoring system, a good correlation was found between the coronary artery disease score and the exercise left ventricular ejection fraction (r = -0.70; p less than 0.001). If the exercise heart rate was 130 beats/min or greater or the age of the patient was 50 years or less, an even better correlation was found (r = -0.73 and r = -0.82, respectively). The exercise ejection fraction (but not the change in ejection fraction, end-diastolic volume and end-systolic volume from rest to exercise) correlated with the extent of coronary artery disease. The exercise ejection fraction is the most important exercise variable that correlates with the extent of coronary artery disease when the latter is assessed quantitatively by a scoring system rather than the conventional method of reporting coronary angiograms. Young age and greater exercise heart rate strengthened the correlation. The change in ejection fraction from rest to exercise is useful in the diagnosis of coronary artery disease

  14. Nontraumatic determination of left ventricular ejection fraction by radionuclide angiocardiography.

    PubMed

    Schelbert, H R; Verba, J W; Johnson, A D; Brock, G W; Alazraki, N P; Rose, F J; Ashburn, W L

    1975-05-01

    Previous reports have suggested that left ventricular ejection fraction can be assessed by recording the passage of peripherally administered radioactive bolus through the heart. The accuracy and validity of this technique were examined in 20 patients undergoing diagnostic cardiac catheterization. 99m-Tc-human serum albumin was injected via a central venous catheter into the superior vena cava and precordial activity recorded with a gamma scintillation camera interfaced to a small digital computer. A computer program was designed to generate time-activity curves from the left ventricular blood pool and to calculate left ventricular ejection fractions from the cyclic fluctuations of the left ventricular time-activity curve which correspond to left ventricular volume changes during each cardiac cycle. The results correlated well with those obtained by biplane cineangiocardiography (r equals 0.94) and indicated that the technique should allow accurate and reproducible determination of left ventricular ejection fraction. The findings, however, demonstrated that the time-activity curve must be generated from a region-of-interest which fits the left ventricular blood pool precisely and must be corrected for contributions arising from noncardiac background structures. This nontraumatic and potentially noninvasive technique appears particularly useful for serial evaluation of the acutely ill patient and for follow-up studies in nonhospitalized patients.

  15. Pharmacotherapy of heart failure with preserved ejection fraction.

    PubMed

    Basaraba, Jade E; Barry, Arden R

    2015-04-01

    Heart failure with preserved ejection fraction (HFpEF) constitutes ~50% of all heart failure diagnoses and is associated with considerable morbidity and mortality. The treatment of HFpEF can be challenging due to a lack of evidence supporting the benefit of various drug therapies. In practice, treatment can be divided into acute and chronic management. Acute therapy for decompensated heart failure is similar for both HFpEF and heart failure with reduced ejection fraction. The mainstay of treatment is diuretics to reduce volume overload and improve dyspnea. Patients with an acute exacerbation of HFpEF and rapid atrial fibrillation (AF) should be rate controlled with negative chronotropic agents. For chronic therapy, patients with HFpEF should not be treated like patients with heart failure with reduced ejection fraction. Chronic management of HFpEF can be simplified by using three strategies based on applicability: treat precipitating conditions (e.g., hypertension, AF), control symptoms by maintaining euvolemia with diuretics, and avoid therapies that have been shown not to be beneficial unless another compelling indication exists. Nondrug interventions for HFpEF include salt and fluid restriction, regular physical activity, and referral to a heart function clinic, if appropriate.

  16. Heart failure with preserved ejection fraction: uncertainties and dilemmas.

    PubMed

    Ferrari, Roberto; Böhm, Michael; Cleland, John G F; Paulus, Walter J S; Pieske, Burkert; Rapezzi, Claudio; Tavazzi, Luigi

    2015-07-01

    Many uncertainties surround the syndrome of heart failure with preserved ejection fraction (HFpEF), which was the topic reviewed in an Expert Meeting at the University of Ferrara. This concluded that the absence of clear diagnostic clinical criteria was the major barrier to progress. There was general agreement that symptoms or signs of heart failure, normal LVEF despite an elevated plasma concentration of natriuretic peptides, and signs of abnormal LV relaxation, LV filling, LV hypertrophy, or left atrial enlargement, or diastolic dysfunction supported the diagnosis. However, HFpEF, like all heart failure syndromes, is heterogeneous in aetiology and pathophysiology, rather than being a single disease. HFpEF may account for about half of all patients with heart failure. The classical risk factors for developing HFpEF include age and co-morbidities, notably hypertension, atrial fibrillation, and the metabolic syndrome. When complicated by increasing congestion requiring hospital admission, the prognosis is poor; 30% or more of patients will die within 1 year (nearly two-thirds die from cardiovascular causes). Patients with chronic stable symptoms have a much better prognosis. Despite many clinical trials, there is no solid evidence that any treatment alters the natural history of HFpEF. Several treatments have shown promising early results and are now being tested in substantial randomized clinical trials. Further basic research is required to better characterize the disease and accelerate progress. Our review highlights the many difficulties encountered in performing randomized clinical trials in HFpEF, often due to difficulties in characterizing HFpEF itself.

  17. Exercise physiology in heart failure and preserved ejection fraction.

    PubMed

    Haykowsky, Mark J; Kitzman, Dalane W

    2014-07-01

    Recent advances in the pathophysiology of exercise intolerance in patients with heart failure with preserved ejection fraction (HFPEF) suggest that noncardiac peripheral factors contribute to the reduced peak V(o2) (peak exercise oxygen uptake) and to its improvement after endurance exercise training. A greater understanding of the peripheral skeletal muscle vascular adaptations that occur with physical conditioning may allow for tailored exercise rehabilitation programs. The identification of specific mechanisms that improve whole body and peripheral skeletal muscle oxygen uptake could establish potential therapeutic targets for medical therapies and a means to follow therapeutic response.

  18. The Association Between Alcohol Consumption and Left Ventricular Ejection Fraction

    PubMed Central

    Li, Zhao; Guo, Xiaofan; Bai, Yinglong; Sun, Guozhe; Guan, Yufan; Sun, Yingxian; Roselle, Abraham Maria

    2016-01-01

    Abstract The results of previous studies on the relation between alcohol consumption and heart failure (HF) have been inconsistent. This study aimed to evaluate the association between alcohol consumption and left ventricular ejection fraction (LVEF) in a general population. A total of 10,824 adults were examined using a multistage cluster sampling method to select a representative sample of individuals who were at least 35-years old. The participants were asked to provide information about their alcohol consumption. Echocardiograms were obtained, and LVEF was calculated using modified Simpson's rule. Of the 10,824 participants included in the present study, 46.1% were males, and the mean participant age was 54 years; age ranged from 35 to 93 years. The overall prevalence of LVEF< 0.50 and LVEF < 0.40 in the studied population was 11.6% and 2.9%, respectively. The prevalence of LVEF < 0.5 and LVEF < 0.04 was higher in both the moderate and heavy drinker groups than in the nondrinker group (P <0.05). Multivariate logistic regression analyses corrected according to the different levels of alcohol consumption showed that moderate and heavy drinkers had an –1.3-fold and 1.2-fold higher risk of LVEF <0.5, respectively, than nondrinkers (OR: 1.381, 95% CI: 1.115–1.711, P = 0.003 for moderate drinkers; OR: 1.246, 95% CI: 1.064–1.460, P = 0.006 for heavy drinkers). Heavy drinkers had an ∼1.5-fold higher risk of decreased LVEF < 0.4 than nondrinkers (OR: 1.482, 95% CI: 1.117–1.965, P = 0.006). Moderate drinkers did not show a risk of decreased LVEF < 0.4 that was significantly higher than that of nondrinkers (OR: 1.183, 95% CI: 0.774–1.808, P = 0.437). According to these results, we concluded that increased alcohol consumption was associated with decreased LVEF compared with no alcohol consumption in this general population. PMID:27227945

  19. The interval ejection fraction: a cineangiographic and radionuclide study

    SciTech Connect

    Kemper, A.J.; Bianco, J.A.; Shulman, R.M.; Folland, E.D.; Parisi, A.F.; Tow, D.E.

    1982-06-01

    To evaluate the clinical usefulness of the first-third ejection fraction (1/3 EF) for detecting patients with coronary artery disease (CAD), resting contrast ventriculography and first-pass radionuclide angiography with a high-count-rate, multicrystal camera system were performed in 47 subjects: 22 normal controls and 25 patients with clinically stable angina pectoris and severe CAD without and with resting wall motion abnormalities. By contrast angiography, only group 3 had depressed global EF or 1/3 EF compared with control. Whereas 11 of 25 CAD patients had global EF outside the normal range, only two of 25 had depressed 1/3 EF. Both had left ventricular asynergy and a depressed global EF. Studies performed using first-pass radionuclide angiography revealed similar results. A wide range of 1/3 EF values was found in normal subjects by both techniques. Thus, the ejection fraction during the first third of systole at rest is of limited value for detecting patients with CAD.

  20. Ejection Fraction and ESPVR. A study from a theoretical perspective.

    PubMed

    Shoucri, Rachad M

    2013-01-01

    A formula derived by using large elastic deformation for the contraction of the myocardium is used to describe the pressure-volume relation (PVR) in the heart left ventricle, it is also used to calculate a mathematical expression for the non-linear end-systolic pressure-volume relation (ESPVR) in the left ventricle. An important feature of the mathematical formalism used is the inclusion of the isovolumic pressure Piso (equal active pressure generated by the myocardium) in the formalism describing the PVR. Relations between the ejection fraction (EF) and parameters describing the non-linear ESPVR are presented. It is shown that the non-linear ESPVR offers a rich collection of parameters that can be used to study the performance of the ventricles, like the areas under the ESPVR (units of energy) or the ordinates of the ESPVR (units of pressure), slopes and intercepts of the curves involved. The mathematical procedure can be easily implemented in a non-invasive way in routine clinical work when ratios of variables are calculated, it necessitates only the non-invasive measurement of the dimensions of the ventricles. Applications to clinical data published in the literature are presented, and they give results that show the consistency of the mathematical formalism used. The implications of the results of this research work on the study of the problem of heart failure with normal or preserved ejection fraction (HFpEF) are discussed.

  1. Isosorbide Mononitrate in Heart Failure with Preserved Ejection Fraction

    PubMed Central

    Redfield, Margaret M.; Anstrom, Kevin J.; Levine, James A.; Koepp, Gabe A.; Borlaug, Barry A.; Chen, Horng H.; LeWinter, Martin M.; Joseph, Susan M.; Shah, Sanjiv J.; Semigran, Marc J.; Felker, G. Michael; Cole, Robert T.; Reeves, Gordon R.; Tedford, Ryan J.; Tang, W.H. Wilson; McNulty, Steven E.; Velazquez, Eric J.; Shah, Monica R.; Braunwald, Eugene

    2015-01-01

    BACKGROUND Nitrates are commonly prescribed to enhance activity tolerance in patients with heart failure and a preserved ejection fraction. We compared the effect of isosorbide mononitrate or placebo on daily activity in such patients. METHODS In this multicenter, double-blind, crossover study, 110 patients with heart failure and a preserved ejection fraction were randomly assigned to a 6-week dose-escalation regimen of isosorbide mononitrate (from 30 mg to 60 mg to 120 mg once daily) or placebo, with subsequent crossover to the other group for 6 weeks. The primary end point was the daily activity level, quantified as the average daily accelerometer units during the 120-mg phase, as assessed by patient-worn accelerometers. Secondary end points included hours of activity per day during the 120-mg phase, daily accelerometer units during all three dose regimens, quality-of-life scores, 6-minute walk distance, and levels of N-terminal pro–brain natriuretic peptide (NT-proBNP). RESULTS In the group receiving the 120-mg dose of isosorbide mononitrate, as compared with the placebo group, there was a nonsignificant trend toward lower daily activity (−381 accelerometer units; 95% confidence interval [CI], −780 to 17; P = 0.06) and a significant decrease in hours of activity per day (−0.30 hours; 95% CI, −0.55 to −0.05; P = 0.02). During all dose regimens, activity in the isosorbide mononitrate group was lower than that in the placebo group (−439 accelerometer units; 95% CI, −792 to −86; P = 0.02). Activity levels decreased progressively and significantly with increased doses of isosorbide mononitrate (but not placebo). There were no significant between-group differences in the 6-minute walk distance, quality-of-life scores, or NT-proBNP levels. CONCLUSIONS Patients with heart failure and a preserved ejection fraction who received isosorbide mononitrate were less active and did not have better quality of life or submaximal exercise capacity than did

  2. Systems Biology Applied to Heart Failure With Normal Ejection Fraction

    PubMed Central

    Mesquita, Evandro Tinoco; Jorge, Antonio Jose Lagoeiro; de Souza, Celso Vale; Cassino, João Paulo Pedroza

    2014-01-01

    Heart failure with normal ejection fraction (HFNEF) is currently the most prevalent clinical phenotype of heart failure. However, the treatments available have shown no reduction in mortality so far. Advances in the omics sciences and techniques of high data processing used in molecular biology have enabled the development of an integrating approach to HFNEF based on systems biology. This study aimed at presenting a systems-biology-based HFNEF model using the bottom-up and top-down approaches. A literature search was conducted for studies published between 1991 and 2013 regarding HFNEF pathophysiology, its biomarkers and systems biology. A conceptual model was developed using bottom-up and top-down approaches of systems biology. The use of systems-biology approaches for HFNEF, a complex clinical syndrome, can be useful to better understand its pathophysiology and to discover new therapeutic targets. PMID:24918915

  3. Heart failure with preserved ejection fraction: emerging drug strategies.

    PubMed

    Zouein, Fouad A; de Castro Brás, Lisandra E; da Costa, Danielle V; Lindsey, Merry L; Kurdi, Mazen; Booz, George W

    2013-07-01

    Approximately half of heart failure patients have a normal ejection fraction, a condition designated as heart failure with preserved ejection fraction (HFpEF). This heart failure subtype disproportionately affects women and the elderly and is commonly associated with other cardiovascular comorbidities, such as hypertension and diabetes. HFpEF is increasing at a steady rate and is predicted to become the leading cause of heart failure within a decade. HFpEF is characterized by impaired diastolic function, thought to be due to concentric remodeling of the heart along with increased stiffness of both the extracellular matrix and myofilaments. In addition, oxidative stress and inflammation are thought to have a role in HFpEF progression, along with endothelial dysfunction and impaired nitric oxide-cyclic guanosine monophosphate-protein kinase G signaling. Surprisingly a number of clinical studies have failed to demonstrate any benefit of drugs effective in heart failure with systolic dysfunction in HFpEF patients. Thus, HFpEF is one of the largest unmet needs in cardiovascular medicine, and there is a substantial need for new therapeutic approaches and strategies that target mechanisms specific for HFpEF. This conclusion is underscored by the recently reported disappointing results of the RELAX trial, which assessed the use of phosphodiesterase-5 inhibitor sildenafil for treating HFpEF. In animal models, endothelial nitric oxide synthase activators and If current inhibitors have shown benefit in improving diastolic function, and there is a rationale for assessing matrix metalloproteinase 9 inhibitors and nitroxyl donors. LCZ696, a combination drug of angiotensin II receptor blocker and neprilysin inhibitor, and the aldosterone receptor antagonist spironolactone are currently in clinical trial for treating HFpEF. Here we present an overview of the etiology and diagnosis of HFpEF that segues into a discussion of new therapeutic approaches emerging from basic research and

  4. Interval ejection fraction: a cineangiographic and radionuclide study

    SciTech Connect

    Kemper, A.J.; Bianco, J.A.; Shulman, R.M.; Folland, E.D.; Paris, A.F.; Tow, D.E.

    1982-06-01

    To evaluate the clinical usefulness of the first-third ejection fraction (1/3 EF) for detecting patients with coronary artery disease (CAD), resting contrast ventriculography and first-pass radionuclide angiography with a high-count-rate, multicrystal camera system were performed in 47 subjects: 22 normal controls (group 1) and 25 patients with clinically stable angina pectoris and severe CAD (mean 2.3 vessels) without (group 2, n = 12) and with (group 3, n = 13) resting wall motion abnormalities. By contrast angiography, only group 3 had depressed global EF or 1/3 EF compared with control (global EF: group 1, 0.71 = 0.09; group 2, 0.67 = 0.09 (NS); group 3, 0.49 = 0.05 (p < 0.01 vs groups 1 and 2); 1/3 EF: group 1, 0.29 = 0.06; group 2, 0.28 = 0.05 (NS); group 3, 0.22 = 0.05 (p < 0.01 vs groups 1 and 2)). Whereas 11 of 25 CAD patients had global EF outside the normal range, only two of 25 had depressed 1/3 EF. Both had left ventricular asynergy and a depressed global EF. Studies performed using first-pass radionuclide angiography revealed similar results, i.e., only four of 25 CAD patients, all with left ventricular asynergy and depressed global EF, had depressed 1/3 EF values. A wide range of 1/3 EF values was found in normal subjects by both techniques. Thus, the ejection fraction during the first third of systole at rest is of limited value for detecting patients with CAD.

  5. Review: Heart failure with preserved ejection fraction in African Americans.

    PubMed

    Shah, Sachil

    2012-01-01

    Heart failure (HF) affects 5,700 000 people in the United States, with heart failure with preserved ejection fraction (HFPEF) being responsible for between 30%-50% of acute admissions. Epidemiological studies and HF registries have found HFPEF patients to be older, hypertensive and to have a history of atrial fibrillation. These findings, however, may not be fully applicable to African Americans, as they have been poorly studied making up only a minority of the test subjects. This review article is intended to discuss the pathophysiology and epidemiology of HFPEF within African Americans, highlight the differences compared to Caucasian populations and review current treatment guidelines. Studies looking at African Americans in particular have shown them to be younger, female and have worse diastolic dysfunction compared to Caucasian populations. African Americans also have been shown to have a worse mortality outcome especially in patients without coronary artery disease. The treatment of HFPEF is primarily symptomatic with no survival benefit seen in randomized controlled trials. Mechanisms postulated for the worse prognosis in African Americans with HFPEF include: greater incidence of hypertension and diastolic dysfunction, undefined race-driven genetic predispositions or relative resistance to medications that treat HF in general. The biological predispositions may also be compounded by inequality of healthcare access; something still felt to exist today. Prospective studies and randomized controlled trials need to be conducted with particular emphasis on African American populations to fully elucidate this disease and to formulate race specific treatment outcomes for the future.

  6. [New therapy concepts for heart failure with preserved ejection fraction].

    PubMed

    Tschöpe, C; Pieske, B

    2015-04-01

    The management of patients with heart failure and preserved ejection fraction (HFpEF) remains challenging and requires an accurate diagnosis. Although currently no convincing therapy that can prolong survival in patients with HFpEF has been established, treatment of fluid retention, heart rate and control of comorbidities are important cornerstones to improve the quality of life and symptoms. In recent years many new therapy targets have been tested for development of successful interventional strategies for HFpEF. Insights into new mechanisms of HFpEF have shown that heart failure is associated with dysregulation of the nitric oxide-cyclic guanosine monophosphate-protein kinase (NO-cGMP-PK) pathway. Two new drugs are currently under investigation to test whether this pathway can be significantly improved by either the neprilysin inhibitor LCZ 696 due to an increase in natriuretic peptides or by the soluble guanylate cyclase stimulator vericiguat, which is also able to increase cGMP. In addition, several preclinical or early phase studies which are currently investigating new mechanisms for matrix, intracellular calcium and energy regulation including the role of microRNAs and new devices are presented and discussed.

  7. [Heart failure with preserved left ventricular ejection fraction].

    PubMed

    Maeder, Micha T; Rickli, Hans

    2013-10-16

    Heart failure with preserved left ventricular ejection fraction (LVEF; HFpEF) is a common type of heart failure in the elderly, and it typically represents advanced hypertensive heart disease. The left ventricle in patients with HFpEF is characterized by concentric remodeling, normal LVEF, but reduced left longitudinal shortening, and importantly diastolic dysfunction. Dyspnoe and fatigue in patients with HFpEF are due to impaired left ventricular filling with a rapid increase in filling pressures and the lack of an increase in stroke volume during exercise. The diagnosis of HFpEF requires the careful exclusion of non-cardiac causes of dyspnoe as well as cardiac causes of dyspnoe associated with preserved LVEF other than HFpEF, primarily coronary artery disease and valve disease. Then, the following findings are required to make a diagnosis of HFpEF: a non-dilated left ventricle with an LVEF >50% and the presence of a significant diastolic impairment, which can be assessed using invasive haemodynamics, echocardiography, natriuretic peptides, or a combination of these tools. In contrast to patients with heart failure and reduced LVEF there is still no established treatment for patients with HFpEF, which prolongs survival or reduces the rate of hospitalizations for heart failure. There is currently however intense research going on in this field, and results from large trials evaluating the effects of various interventions on clinical endpoints are expected within the next years.

  8. Serial measurements of left ventricular ejection fraction by radionuclide angiography early and late after myocardial infarction.

    PubMed

    Schelbert, H R; Henning, H; Ashburn, W L; Verba, J W; Karliner, J S; O'Rourke, R A

    1976-10-01

    The left ventricular ejection fraction was determined serially with radioisotope angiography in 63 patients with acute myocardial infarction. After the peripheral injection of a bolus of technetium-99m, precordial radioactivity was recorded with a gamma scintillation camera and the ejection fraction calculated from the high frequency left ventricular time-activity curve. Since this technique requires no assumptions with respect to left ventricular geometry, it is particularly useful in patients with segmental left ventricular dysfunction. Serial measurements during the first 5 days after hospital admission were made in 50 patients, 30 of whom were studied during the subsequent 2 to 39 months (mean 19.9 months). Late follow-up serial studies were also performed in an additional 13 patients who had only one measurement of the left ventricular ejection fraction during the early postinfarction period. Early after infarction, the left ventricular ejection fraction was normal (more than 0.52) in only 15 of the 63 patients, and averaged 0.52 +/- 0.05 (standard deviation) in the 27 patients with an uncomplicated infarct. The ejection fraction was reduced in 24 patients with mild to moderate left ventricular failure (0.40 +/- 0.05, P less than 0.0001) and in the 12 patients with overt pulmonary edema (0.33 +/- 0.07, P less than 0.0001). In 35 patients the ejection fraction correlated with the mean pulmonary arterial wedge pressure (r = 0.72). In 15 patients with normal left ventricular wall motion by heart motion videotracking, the ejection fraction was significantly higher (0.53 +/- 0.08) than in the 26 patients with regional left ventricular dysfunction (0.41 +/- 0.10, P less than 0.0001). During the early postinfarction period, the left ventricular ejection fraction improved in 55 percent of patients and remained unchanged or decreased in 45 percent. A further increase in the ejection fraction was noted in 61 percent of patients during the late follow-up period. Patients

  9. Diastolic dysfunction and heart failure with a preserved ejection fraction: Relevance in critical illness and anaesthesia

    PubMed Central

    Maharaj, R.

    2012-01-01

    Epidemiological and clinical studies suggest that HF with a preserved ejection fraction will become the more common form of HF which clinicians will encounter. The spectrum of diastolic disease extends from the asymptomatic phase to fulminant cardiac failure. These patients are commonly encountered in operating rooms and critical care units. A clearer understanding of the underlying pathophysiology and clinical implications of HF with a preserved ejection fraction is fundamental to directing further research and to evaluate interventions. This review highlights the impact of diastolic dysfunction and HF with a preserved ejection fraction during the perioperative period and during critical illness. PMID:23960679

  10. Comparison of the reliability of E/E' to estimate pulmonary capillary wedge pressure in heart failure patients with preserved ejection fraction versus those with reduced ejection fraction.

    PubMed

    Matsushita, Kenichi; Minamishima, Toshinori; Goda, Ayumi; Ishiguro, Haruhisa; Kosho, Hideyasu; Sakata, Konomi; Satoh, Toru; Yoshino, Hideaki

    2015-12-01

    Accurate assessment of pulmonary capillary wedge pressure (PCWP) is essential for physicians to effectively manage patients with acute decompensated heart failure. The ratio of early transmittal velocity to tissue Doppler mitral annular early diastolic velocity (E/E') is used to estimate PCWP noninvasively in a wide range of cardiac patients. However, it remains contentious as to whether mitral E/E' is a reliable predictor of PCWP. In the present study, acute heart failure patients were divided into two groups on the basis of left ventricular (LV) systolic function: those with preserved ejection fraction (HFpEF) and those with reduced ejection fraction (HFrEF). The usefulness of mitral E/E' in estimating PCWP was compared between the two groups. Fifty consecutive patients who were admitted with acute decompensated heart failure and underwent both right-sided cardiac catheterization and transthoracic echocardiography during hospitalization were analyzed retrospectively. Pearson's correlation was used to evaluate associations between Doppler parameters and PCWP. E/E' was positively correlated with PCWP (r = 0.56, P = 0.01) in the heart failure with preserved ejection fraction group. However, no significant relationship was observed between PCWP and mitral E/E' (P = 0.85) in the heart failure with reduced ejection fraction group. There were no significant correlations between any of the conventional parameters considered (LVEF, left atrial dimension, E/A, IVRT, and DT) with PCWP in either group. In conclusion, mitral E/E' is useful for estimating PCWP in patients with acute heart failure with preserved ejection fraction but may not in those with reduced ejection fraction.

  11. How do patients with heart failure with preserved ejection fraction die?

    PubMed

    Chan, Michelle M Y; Lam, Carolyn S P

    2013-06-01

    Understanding how patients with heart failure with preserved ejection fraction (HFPEF) die provides insight into the natural history and pathophysiology of this complex syndrome, thereby allowing better prediction of response to therapy in designing clinical trials. This review summarizes the current state of knowledge surrounding mortality rates, modes of death, and prognostic factors in HFPEF. Despite the lack of uniform reporting, the following conclusions may be drawn from previous studies. The mortality burden of HFPEF is substantial, ranging from 10% to 30% annually, and higher in epidemiological studies than in clinical trials. Mortality rates compared with heart failure with reduced ejection fraction (HFREF) appear to be strongly influenced by the type of study, but are clearly elevated compared with age- and co-morbidity-matched controls without heart failure. The majority of deaths in HFPEF are cardiovascular deaths, comprising 51-60% of deaths in epidemiological studies and ∼70% in clinical trials. Among cardiovascular deaths, sudden death and heart failure death are the leading cardiac modes of death in HFPEF clinical trials. Compared with HFREF, the proportions of cardiovascular deaths, sudden death, and heart failure deaths are lower in HFPEF. Conversely, non-cardiovascular deaths constitute a higher proportion of deaths in HFPEF than in HFREF, particularly in epidemiological studies, where this difference may be related to fewer coronary heart deaths in HFPEF. Key mortality risk factors, including age, gender, body mass index, burden of co-morbidities, and coronary artery disease, offer some explanation for the differences in mortality rates observed across studies.

  12. Heart Failure with Preserved Ejection Fraction in the Elderly: Scope of the Problem

    PubMed Central

    Upadhya, Bharathi; Taffet, George E; Cheng, Che Ping; Kitzman, Dalane W

    2017-01-01

    Heart failure with preserved ejection fraction (HFpEF) is the most common form of heart failure (HF) in older adults, particularly women, and is increasing in prevalence as the population ages. With morbidity and mortality on par with HF with reduced ejection fraction, it remains a most challenging clinical syndrome for the practicing clinician and basic research scientist. Originally considered to be predominantly caused by diastolic dysfunction, more recent insights indicate that HFpEF in older persons is typified by a broad range of cardiac and non-cardiac abnormalities and reduced reserve capacity in multiple organ systems. The globally reduced reserve capacity is driven by: 1) inherent age-related changes; 2) multiple, concomitant co-morbidities; 3) HFpEF itself, which is likely a systemic disorder. These insights help explain why: 1) comorbidities are among the strongest predictors of outcomes; 2) approximately 50% of clinical events in HFpEF patients are non-cardiovascular; 3) clinical drug trials in HFpEF have been negative on their primary outcomes. Embracing HFpEF as a true geriatric syndrome, with complex, multi-factorial pathophysiology and clinical heterogeneity could provide new mechanistic insights and opportunities for progress in management. PMID:25754674

  13. Fractionation of hydrogen and deuterium on Venus due to collisional ejection

    NASA Astrophysics Data System (ADS)

    Gurwell, M. A.; Yung, Y. L.

    1993-02-01

    The collisional ejection process for hydrogen on Venus is reanalyzed. Improved values for the efficiency of H and D escape as a function of the ionospheric temperature are reported. It is proposed that the reduction of the hydrogen flux for collisional ejection be reduced from 8 to 3.5 x 10 exp 6/sq cm/s, and a revised D/H fractional factor of 0.47 due to collisional ejection is suggested. The resulting deuterium flux is 3.1 x 10 exp 4/sq cm/s, roughly six times the flux due to charge exchange, making collisional ejection the dominant escape mechanism for deuterium on Venus.

  14. Left Atrial Structure and Function in Heart Failure with Preserved Ejection Fraction: A RELAX Substudy

    PubMed Central

    McNulty, Steven E.; Hernandez, Adrian F.; Semigran, Marc J.; Lewis, Gregory D.; Jerosch-Herold, Michael; Kim, Raymond J.; Redfield, Margaret M.; Kwong, Raymond Y.

    2016-01-01

    Given the emerging recognition of left atrial structure and function as an important marker of disease in heart failure with preserved ejection fraction (HF-pEF), we investigated the association between left atrial volume and function with markers of disease severity and cardiac structure in HF-pEF. We studied 100 patients enrolled in the PhosphdiesteRasE-5 Inhibition to Improve CLinical Status and EXercise Capacity in Diastolic Heart Failure (RELAX) trial who underwent cardiac magnetic resonance (CMR), cardiopulmonary exercise testing, and blood collection before randomization. Maximal left atrial volume index (LAVi; N = 100), left atrial emptying fraction (LAEF; N = 99; including passive and active components (LAEFP, LAEFA; N = 80, 79, respectively) were quantified by CMR. After adjustment for multiple testing, maximal LAVi was only associated with age (ρ = 0.39), transmitral filling patterns (medial E/e’ ρ = 0.43), and N-terminal pro-BNP (NT-proBNP; ρ = 0.65; all p<0.05). Lower LAEF was associated with older age, higher transmitral E/A ratio and higher NT-proBNP. Peak VO2 and VE/VCO2 slope were not associated with left atrial structure or function. After adjustment for age, sex, transmitral E/A ratio, CMR LV mass, LV ejection fraction, and creatinine clearance, NT-proBNP remained associated with maximal LAVi (β = 0.028, p = 0.0007) and total LAEF (β = -0.033, p = 0.001). Passive and active LAEF were most strongly associated with age and NT-proBNP, but not gas exchange or other markers of ventricular structure or filling properties. Left atrial volume and emptying function are associated most strongly with NT-proBNP and diastolic filling properties, but not significantly with gas exchange, in HFpEF. Further research to explore the relevance of left atrial structure and function in HF-pEF is warranted. PMID:27812147

  15. Heart Failure and Mid-Range Ejection Fraction: Implications of Recovered Ejection Fraction for Exercise Tolerance and Outcomes

    PubMed Central

    Nadruz, Wilson; West, Erin; Santos, Mário; Skali, Hicham; Groarke, John D.; Forman, Daniel E.; Shah, Amil M.

    2016-01-01

    Background Evidence-based therapies for heart failure (HF) differ significantly according to left ventricular ejection fraction (LVEF). However, few data are available regarding the phenotype and prognosis of HF patients with mid-range LVEF of 40–55%, and the impact of recovered systolic function on the clinical features, functional capacity and outcomes of this population is not known. Methods and Results We studied 944 HF patients who underwent clinically indicated cardiopulmonary exercise testing. The study population was categorized according to LVEF as: HFrEF (LVEF<40%; n=620); HFmEF (LVEF was consistently between 40–55%; n=107); HFm-recEF (LVEF=40–55% but previous LVEF<40%; n=170); and HFpEF (LVEF>55%; n=47). HFmEF and HFm-recEF had similar clinical characteristics, which were intermediate between those of HFrEF and HFpEF, and comparable values of predicted peak oxygen consumption and minute-ventilation/carbon dioxide production slope, which were better than HFrEF and similar to HFpEF. After a median of 4.4 [2.9–5.7] years, there were 253 composite events (death, left ventricular assistant device implantation or transplantation). In multivariable Cox-regression analysis, HFm-recEF had lower risk of composite events than HFrEF (HR=0.25; 95%CI=0.13–0.47) and HFmEF (HR=0.31; 95%CI=0.15–0.67), and similar prognosis when compared to HFpEF. In contrast, HFmEF tended to show intermediate risk of outcomes in comparison with HFpEF and HFrEF, albeit not reaching statistical significance in fully adjusted analyses. Conclusions HF patients with mid-range LVEF demonstrate a distinct clinical profile from HFpEF and HFrEF patients, with objective measures of functional capacity similar to HFpEF. Within the mid-range LVEF HF population, recovered systolic function is a marker of more favorable prognosis. PMID:27009553

  16. Are beta-blockers effective in heart failure with preserved ejection fraction?

    PubMed

    Alegría, Javier; Rada, Gabriel

    2016-11-02

    Beta-blockers constitute standard therapy for heart failure with reduced ejection. However, their role in patients with preserved ejection fraction is not clear. Searching in Epistemonikos database, which is maintained by screening multiple databases, we identified four systematic reviews covering 19 primary studies, including seven randomized trials answering the question of this summary. We combined the evidence using meta-analysis and generated a summary of findings table following the GRADE approach. We concluded the use of beta-blockers probably leads to little or no difference in the risk of death or hospitalization in patients with heart failure with preserved ejection fraction.

  17. Outcome of Heart Failure with Preserved Ejection Fraction: A Multicentre Spanish Registry

    PubMed Central

    Castillo, Juan C; Anguita1, Manuel P; Jiménez, Manuel

    2009-01-01

    Background: Studies on clinical features, treatment and prognosis of patients with congestive heart failure (CHF) and preserved left ventricular ejection fraction (LVEF) are few and their results frequently conflicting. Aims: To investigate the characteristics and long term prognosis of patients with CHF and preserved (≥ 45%) LVEF. Methods and Results: We conducted a prospective multicentre study with 4720 patients attended in 62 heart failure clinics from 1999 to 2003 in Spain (BADAPIC registry). LVEF was preserved in 30% patients. Age, female gender, prevalence of atrial fibrillation, hypertension and non-ischaemic cardiopathy were all significantly greater in patients with preserved LVEF. Mean follow-up was 40±12 months. Mortality and other cardiovascular complication rates during follow up were similar in both groups. On multivariate analysis ejection fraction was not an independent predictor for mortality. Survival at one and five years was similar in both groups (79% and 59% for patients with preserved LVEF and 78% and 57% for those with reduced LVEF, respectively). Conclusions: In the BADAPIC registry, a high percentage of heart failure patients had preserved LVEF. Although clinical differences were seen between groups, morbidity and mortality were similar in both groups. PMID:21037850

  18. Riser Pattern: Another Determinant of Heart Failure With Preserved Ejection Fraction.

    PubMed

    Komori, Takahiro; Eguchi, Kazuo; Saito, Toshinobu; Hoshide, Satoshi; Kario, Kazuomi

    2016-10-01

    Paradoxical increase in blood pressure (BP) during sleep, exceeding those of awake BP, is called the "riser" BP pattern, and known as an abnormal circadian BP rhythm, has been reported to be associated with adverse cardiovascular prognoses. However, the significance of ambulatory BP in heart failure patients with preserved ejection fraction (HFpEF) has never been reported. Here, we tested our hypothesis that abnormal circadian BP rhythm is associated with HFpEF. The authors enrolled 508 patients with hospitalized HF (age 68±13 years; 315 men, 193 women). There were 232 cases of HFpEF and 276 cases of heart failure with reduced ejection fraction (HFrEF). The riser BP pattern was significantly more frequent in the HFpEF (28.9%) group compared with the HFrEF group (19.9%). In a multivariable logistic regression analysis, the riser BP pattern was associated with HFpEF (odds ratio, 1.73; 95% confidence interval, 1.02-2.91; P=.041) independent of the other covariates. In conclusion, the riser BP pattern was associated with HFpEF.

  19. Left Ventricle Hypertrophy, Dilatation and Ejection Fraction Changes Before and After Kidney Transplantation

    PubMed Central

    Tayebi-Khosroshahi, Hamid; Abbasnezhad, Mohsen; Habibzadeh, Afshin; Bakhshandeh, Masumeh; Chaichi, Parastoo

    2013-01-01

    Background Patients with end stage renal disease (ESRD) are at risk of complications in different organs including cardiovascular system. Renal transplantation is the best choice in these patients which diminishes these complications. It is observed that after renal transplantation, cardiac parameters have appropriate improvement. Current study evaluates echocardiographic findings in renal transplant recipients before and after kidney transplantation. Methods In an analytic cross sectional study, 30 patients (50% male, mean age of 45.57 ± 13.32 years) with ESRD who underwent renal transplantation were studied. All patients had echocardiographic studies after the last dialysis before and 6 months after transplantation. Echocardiographic study was done by Color Doppler two dimension methods and left ventricle ejection fraction was measured by Simpson method. All echocardiograms before and after transplantation were interpreted by the same cardiologist. Results Mean left ventricle ejection fraction before and after renal transplantation was 53.83±10.14% and 57.33±4.49%, respectively (P = 0.09). Left ventricle hypertrophy, mitral regurgitation and tricuspid regurgitation existed in 46.7%, 76.7% and 33.3% respectively, which was improved in 30%, 50% and 33.3% after renal transplantation. Conclusion According to the results of current study it is suggested that renal transplantation could improve left ventricle parameters in patients with end stage renal disease.

  20. Breakthrough in heart failure with preserved ejection fraction: are we there yet?

    PubMed Central

    Lim, Shir Lynn; Lam, Carolyn Su Ping

    2016-01-01

    Heart failure with preserved ejection fraction (HFPEF) is a global health problem of considerable socioeconomic burden. It is projected to worsen with the aging population worldwide. The lack of effective therapies underscores our incomplete understanding of this complex heterogeneous syndrome. A novel paradigm has recently emerged, in which central roles are ascribed to systemic inflammation and generalized endothelial dysfunction in the pathophysiology of HFPEF. In this review, we discuss the role of the endothelium in cardiovascular homeostasis and how deranged endothelial-related signaling pathways contribute to the development of HFPEF. We also review the novel therapies in various stages of research and development that target different components of this signaling pathway. PMID:26767852

  1. Automatic analysis of left ventricular ejection fraction using stroke volume images.

    PubMed

    Nelson, T R; Verba, J W; Bhargava, V; Shabetai, R; Slutsky, R

    1983-01-01

    The purpose of this study was to analyze, validate, and report on an automatic computer algorithm for analyzing left ventricular ejection fraction and to indicate future applications of the technique to other chambers and more advanced measurements. Thirty-eight patients were studied in the cardiac catheterization laboratory by equilibrium radionuclide ventriculography and concurrent contrast ventriculography. The temporal and spatial behavior of each picture element in a filtered stroke volume image series was monitored throughout the cardiac cycle. Pixels that met specific phase, amplitude, and derivative criteria were assigned to the appropriate chamber. Volume curves were generated from regions of interest for each chamber to enable calculation of the left ventricular ejection fraction. Left ventricular ejection fractions showed a good correlation (r = 0.89) between the two techniques. Ejection fractions ranged between 0.12 and 0.88, showing a wide range of application. It is concluded that automatic analysis of left ventricular ejection fraction is possible using the present algorithm and will be useful in improving the reproducibility and providing more accurate information during exercise protocols, pharmaceutical interventions, and routine clinical studies.

  2. Outcomes and worsening renal function in patients hospitalized with heart failure with preserved ejection fraction.

    PubMed

    Sharma, Kavita; Hill, Terence; Grams, Morgan; Daya, Natalie R; Hays, Allison G; Fine, Derek; Thiemann, David R; Weiss, Robert G; Tedford, Ryan J; Kass, David A; Schulman, Steven P; Russell, Stuart D

    2015-11-15

    Heart failure with preserved ejection fraction (HFpEF) has been described as a disease of elderly subjects with female predominance and hypertension. Our clinical experience suggests patients with HFpEF from an urban population are far more heterogenous, with greater co-morbidities and significant inhospital morbidity. There are limited data on the hospitalization course and outcomes in acute decompensated HFpEF. Hospitalizations for acute heart failure at our institution from July 2011 to June 2012 were identified by International Classification of Diseases, Ninth Revision, codes and physician review for left ventricular ejection fraction ≥50% and were reviewed for patient characteristics and clinical outcomes. Worsening renal function (WRF) was defined as creatinine increase of ≥0.3 mg/dl by 72 hours after admission. Hospital readmission and mortality data were captured from electronic medical records and the Social Security Death Index. Of 434 heart failure admissions, 206 patients (47%) with HFpEF were identified. WRF developed in 40%, the highest reported in HFpEF to date, and was associated with higher blood pressure and lower volume of diuresis. Compared to previous reports, hospitalized patients with HFpEF were younger (mean age 63.2 ± 13.6 years), predominantly black (74%), and had more frequent and severe co-morbidities: hypertension (89%), diabetes (56%), and chronic kidney disease (55%). There were no significant differences in 1- and 12-month outcomes by gender, race, or WRF. In conclusion, we found hospitalized patients with HFpEF from an urban population develop a high rate of WRF are younger than previous cohorts, often black, and have greater co-morbidities than previously described.

  3. Cardiac I123-MIBG Correlates Better than Ejection Fraction with Symptoms Severity in Systolic Heart Failure

    PubMed Central

    Miranda, Sandra M.; Moscavitch, Samuel D.; Carestiato, Larissa R.; Felix, Renata M.; Rodrigues, Ronaldo C.; Messias, Leandro R.; Azevedo, Jader C.; Nóbrega, Antonio Cláudio L.; Mesquita, Evandro Tinoco; Mesquita, Claudio Tinoco

    2013-01-01

    Background The association of autonomic activation, left ventricular ejection fraction (LVEF) and heart failure functional class is poorly understood. Objective Our aim was to correlate symptom severity with cardiac sympathetic activity, through iodine-123-metaiodobenzylguanidine (123I-MIBG) scintigraphy and with LVEF in systolic heart failure (HF) patients without previous beta-blocker treatment. Methods Thirty-one patients with systolic HF, class I to IV of the New York Heart Association (NYHA), without previous beta-blocker treatment, were enrolled and submitted to 123I-MIBG scintigraphy and to radionuclide ventriculography for LVEF determination. The early and delayed heart/mediastinum (H/M) ratio and the washout rate (WR) were performed. Results According with symptom severity, patients were divided into group A, 13 patients in NYHA class I/II, and group B, 18 patients in NYHA class III/IV. Compared with group B patients, group A had a significantly higher LVEF (25% ± 12% in group B vs. 32% ± 7% in group A, p = 0.04). Group B early and delayed H/M ratios were lower than group A ratios (early H/M 1.49 ± 0.15 vs. 1.64 ± 0.14, p = 0.02; delayed H/M 1.39 ± 0.13 vs. 1.58 ± 0.16, p = 0.001, respectively). WR was significantly higher in group B (36% ± 17% vs. 30% ± 12%, p= 0.04). The variable that showed the best correlation with NYHA class was the delayed H/M ratio (r= -0.585; p=0.001), adjusted for age and sex. Conclusion This study showed that cardiac 123I-MIBG correlates better than ejection fraction with symptom severity in systolic heart failure patients without previous beta-blocker treatment. PMID:23917506

  4. Submaximal oxygen uptake kinetics, functional mobility, and physical activity in older adults with heart failure and reduced ejection fraction

    PubMed Central

    Hummel, Scott L; Herald, John; Alpert, Craig; Gretebeck, Kimberlee A; Champoux, Wendy S; Dengel, Donald R; Vaitkevicius, Peter V; Alexander, Neil B

    2016-01-01

    Background Submaximal oxygen uptake measures are more feasible and may better predict clinical cardiac outcomes than maximal tests in older adults with heart failure (HF). We examined relationships between maximal oxygen uptake, submaximal oxygen kinetics, functional mobility, and physical activity in older adults with HF and reduced ejection fraction. Methods Older adults with HF and reduced ejection fraction (n = 25, age 75 ± 7 years) were compared to 25 healthy age- and gender-matched controls. Assessments included a maximal treadmill test for peak oxygen uptake (VO2peak), oxygen uptake kinetics at onset of and on recovery from a submaximal treadmill test, functional mobility testing [Get Up and Go (GUG), Comfortable Gait Speed (CGS), Unipedal Stance (US)], and self-reported physical activity (PA). Results Compared to controls, HF had worse performance on GUG, CGS, and US, greater delays in submaximal oxygen uptake kinetics, and lower PA. In controls, VO2peak was more strongly associated with functional mobility and PA than submaximal oxygen uptake kinetics. In HF patients, submaximal oxygen uptake kinetics were similarly associated with GUG and CGS as VO2peak, but weakly associated with PA. Conclusions Based on their mobility performance, older HF patients with reduced ejection fraction are at risk for adverse functional outcomes. In this population, submaximal oxygen uptake measures may be equivalent to VO2 peak in predicting functional mobility, and in addition to being more feasible, may provide better insight into how aerobic function relates to mobility in older adults with HF. PMID:27594875

  5. Two-dimensional echocardiographic assessment of left ventricular volumes and ejection fraction in children

    SciTech Connect

    Mercier, J.C.; DiSessa, T.G.; Jarmakani, J.M.; Nakanishi, T.; Hiraishi, S.; Isabel-Jones, J.; Friedman, W.F.

    1982-05-01

    The ability of two-dimensional echocardiography to measure left ventricular volumes and ejection fraction was evaluated in 25 children with congenital heart disease. Dimensions and planimetered areas were obtained in the short-axis view at the mitral valve and high and low papillary muscle levels and in the apical two- and four-chamber views. Eight algorithms using five geometric models were assessed. Left ventricular end-diastolic volume, end-systolic volume and ejection fraction were compared with data from biplane cineangiocardiograms. The correlation varied with the algorithm used. Algorithms using short-axis views appeared superior to those using only apical long-axis views. Four algorithms estimated left ventricular volumes with equal accuracy (Simpson's rule, assuming the ventricle to be a truncated cone; Simpson's rule, algorithm that best estimated left ventricular ejection fraction was the ellipsoid biplane formula using the short-axis view at the papillary muscle level (r = 0.91, slope = 0.94, SEE = 6.7%). Thus, two-dimensional echocardiography can accurately assess left ventricular volumes and ejection fraction in children with congenital heart disease.

  6. Reduced First-Phase Ejection Fraction and Sustained Myocardial Wall Stress in Hypertensive Patients With Diastolic Dysfunction

    PubMed Central

    Gu, Haotian; Li, Ye; Fok, Henry; Simpson, John; Kentish, Jonathan C.; Shah, Ajay M.

    2017-01-01

    Impaired shortening deactivation of cardiac myocytes could sustain myocardial contraction, preserving ejection fraction at the expense of diastolic dysfunction. We examined the relationship between first-phase ejection fraction (EF1), the fraction of left ventricular volume ejected from the start of systole to the time of the first peak in left ventricular pressure (corresponding to the time of maximal ventricular shortening) to the duration of myocardial contraction and diastolic function in patients with hypertension (n=163), and varying degrees of diastolic dysfunction. Left ventricular systolic pressure was estimated by carotid tonometry; time-resolved left ventricular cavity and wall volume were obtained by echocardiography with speckle wall tracking. Measurements were repeated after nitroglycerin, a drug known to influence ventricular dynamics, in a subsample (n=18) of patients. EF1 and time of onset of ventricular relaxation (as determined from the temporal pattern of myocardial wall stress) were independently correlated with diastolic relaxation as measured by tissue Doppler early diastolic mitral annular velocity (E′, standardized regression coefficients 0.48 and −0.34 for EF1 and time of onset of ventricular relaxation, respectively, each P<0.001, irrespective of adjustment for age, sex, antihypertensive treatment, measures of afterload, and ventricular geometry) and with diastolic function measured by the ratio of transmitral Doppler early filling velocity (E) to E′ (E/E′, regression coefficients −0.34 and 0.34, respectively, each P<0.001). Nitroglycerin increased EF1, decreased time of onset of ventricular relaxation, and improved diastolic function (each P<0.05). Hypertensive patients with diastolic dysfunction exhibit reduced EF1 which may sustain myocardial contraction, preserving systolic ejection fraction at the expense of impaired diastolic function. PMID:28223475

  7. Heart failure preserved ejection fraction (HFpEF): an integrated and strategic review.

    PubMed

    Lekavich, Carolyn L; Barksdale, Debra J; Neelon, Virginia; Wu, Jia-Rong

    2015-11-01

    In the USA, 5.7 million Americans ≥20 years have heart failure (HF) and heart failure preserved ejection fraction (HFpEF) accounts for at least 50 % of all hospital admissions for HF. HFpEF has no single guideline for diagnosis or treatment, the patient population is heterogeneously and inconsistently described, and longitudinal studies are lacking. The primary aims of this manuscript were to present an integrated review of the current state of the science on HFpEF, demonstrate gaps in the literature and provide the rationale for the design and implementation of future research to yield insights into the syndrome of HFpEF. The scientific literature was comprehensively reviewed on HFpEF pathophysiology, patient characteristics, diagnostic criteria, echocardiography biomarkers, treatment approaches and outcomes. Discrepancies in patient characteristics, diagnostic criteria, study methods and echocardiographic biomarkers were identified. This review indicates that no single test or guideline exists for diagnosis or treatment for HFpEF; heterogeneity of the population is complicated by multiple comorbidities that factor into etiology, race and age are likely important factors that define the phenotype, and limited information is available that designates early markers of impending HFpEF. Studies designed and adequately powered to study the impact of race and age along with consistent use of HFpEF diagnostic criteria are critically needed to further incident HFpEF research.

  8. High-Intensity Interval Training in Patients With Heart Failure With Reduced Ejection Fraction

    PubMed Central

    Halle, Martin; Conraads, Viviane; Støylen, Asbjørn; Dalen, Håvard; Delagardelle, Charles; Larsen, Alf-Inge; Hole, Torstein; Mezzani, Alessandro; Van Craenenbroeck, Emeline M.; Videm, Vibeke; Beckers, Paul; Christle, Jeffrey W.; Winzer, Ephraim; Mangner, Norman; Woitek, Felix; Höllriegel, Robert; Pressler, Axel; Monk-Hansen, Tea; Snoer, Martin; Feiereisen, Patrick; Valborgland, Torstein; Kjekshus, John; Hambrecht, Rainer; Gielen, Stephan; Karlsen, Trine; Prescott, Eva; Linke, Axel

    2017-01-01

    Background: Small studies have suggested that high-intensity interval training (HIIT) is superior to moderate continuous training (MCT) in reversing cardiac remodeling and increasing aerobic capacity in patients with heart failure with reduced ejection fraction. The present multicenter trial compared 12 weeks of supervised interventions of HIIT, MCT, or a recommendation of regular exercise (RRE). Methods: Two hundred sixty-one patients with left ventricular ejection fraction ≤35% and New York Heart Association class II to III were randomly assigned to HIIT at 90% to 95% of maximal heart rate, MCT at 60% to 70% of maximal heart rate, or RRE. Thereafter, patients were encouraged to continue exercising on their own. Clinical assessments were performed at baseline, after the intervention, and at follow-up after 52 weeks. Primary end point was a between-group comparison of change in left ventricular end-diastolic diameter from baseline to 12 weeks. Results: Groups did not differ in age (median, 60 years), sex (19% women), ischemic pathogenesis (59%), or medication. Change in left ventricular end-diastolic diameter from baseline to 12 weeks was not different between HIIT and MCT (P=0.45); left ventricular end-diastolic diameter changes compared with RRE were −2.8 mm (−5.2 to −0.4 mm; P=0.02) in HIIT and −1.2 mm (−3.6 to 1.2 mm; P=0.34) in MCT. There was also no difference between HIIT and MCT in peak oxygen uptake (P=0.70), but both were superior to RRE. However, none of these changes was maintained at follow-up after 52 weeks. Serious adverse events were not statistically different during supervised intervention or at follow-up at 52 weeks (HIIT, 39%; MCT, 25%; RRE, 34%; P=0.16). Training records showed that 51% of patients exercised below prescribed target during supervised HIIT and 80% above target in MCT. Conclusions: HIIT was not superior to MCT in changing left ventricular remodeling or aerobic capacity, and its feasibility remains unresolved in

  9. Determination of right ventricular ejection fraction in children with cystic fibrosis, using krypton-81m

    SciTech Connect

    Piepsz, A.; Ham, H.R.; Millet, E.; Dab, I.

    1984-01-01

    The diagnosis of cor pulmonale and incipient heart failure remains difficult to assess in cystic fibrosis (CF) on the basis of the clinical as well as the biological parameters. The measurement of the right ventricular ejection fraction has been facilitated these last years by the introduction of the radionuclide methods. Methodological difficulties are however encountered when Tc-99m RBC are used, and are mainly related to heart chambers superposition (equilibrium method) or the low count density (first pass method). Few papers have been published on RVEF in cystic fibrosis and the results are somewhat contradictory. The authors have recently introduced a new method for the determination of RVEF, using equilibrium study during continuous injection of Kr-81m in glucose solution. This method offers several advantages related to an increased accuracy and a favorable dosimetry. In 25 patients aged 2 to 23 years with CF, one or more RVEF studies were performed. The severity of the disease was evaluated on the basis of the clinical Schwachman score, the lung function tests, the ventilation scan and the pa02. RVEF tended to decrease with the progression of the lung disease, although, owing to the spread of the results, no RVEF could be predicted on the basis of the other parameters. The decrease of RVEF in patients with advanced lung disease was moderate and terminal lung disease was sometimes associated with normal right heart contractility.

  10. Radionuclide fourier amplitude analysis to predict post-aneurysmectomy ejection fraction

    SciTech Connect

    McCarthy, D.M.; Kleaveland, J.P.; Makler, P.T. Jr.; Alavi, A.

    1984-01-01

    Post-operative LV ejection fraction (EF) is an important determinant of outcome following aneurysmectomy but is difficult to predict noninvasively. First harmonic Fourier analysis of radionuclide angiography (RNA) in patients with aneurysms gives characteristic phase and amplitude images which delineate contractile and dyskinetic regions. Since pixel amplitude is proportional to stroke counts, the summed amplitude values from the contractile region (CR) and the aneurysm should reflect regional stroke volumes. A predicted post-operative LVEF may be determined from the pre-operative global LVEF and the proportion of the total amplitude located in the CR. The authors studied 19 patients undergoing LV aneurysmectomy with pre- and post-operative RNA. Three patients were excluded for technical reasons, leaving 16 patients for analysis. There were 13 males, and the mean age was 56.8 yrs (range 45-78). All patients had a history of anterior myocardial infarction and were undergoing surgery for recurrent sustained ventricular tachycardia. The global LVEF increased from 0.25 +- .13 (sd) pre-operatively to 0.38+-.11 following surgery (p<.001). The predicted post-operative LVEF (from amplitude analysis of the pre-operative RNA) averaged 0.35 +- .13 and correlated significantly with the actual post-operative LVEf (r=0.87, SEE=.06, p<.01). The results suggest that the LVEF following aneurysmectomy can be predicted from Fourier amplitude analysis of the pre-operative RNA.

  11. Exercise intolerance in heart failure with preserved ejection fraction: more than a heart problem

    PubMed Central

    Upadhya, Bharathi; Haykowsky, Mark J; Eggebeen, Joel; Kitzman, Dalane W

    2015-01-01

    Heart failure (HF) with preserved ejection fraction (HFpEF) is the most common form of HF in older adults, and is increasing in prevalence as the population ages. Furthermore, HFpEF is increasing out of proportion to HF with reduced EF (HFrEF), and its prognosis is worsening while that of HFrEF is improving. Despite the importance of HFpEF, our understanding of its pathophysiology is incomplete, and optimal treatment remains largely undefined. A cardinal feature of HFpEF is reduced exercise tolerance, which correlates with symptoms as well as reduced quality of life. The traditional concepts of exercise limitations have focused on central dysfunction related to poor cardiac pump function. However, the mechanisms are not exclusive to the heart and lungs, and the understanding of the pathophysiology of this disease has evolved. Substantial attention has focused on defining the central versus peripheral mechanisms underlying the reduced functional capacity and exercise tolerance among patients with HF. In fact, physical training can improve exercise tolerance via peripheral adaptive mechanisms even in the absence of favorable central hemodynamic function. In addition, the drug trials performed to date in HFpEF that have focused on influencing cardiovascular function have not improved exercise capacity. This suggests that peripheral limitations may play a significant role in HF limiting exercise tolerance, a hallmark feature of HFpEF. PMID:26089855

  12. Foundations of Pharmacotherapy for Heart Failure With Reduced Ejection Fraction: Evidence Meets Practice, Part I.

    PubMed

    Paul, Sara; Page, Robert L

    2016-01-01

    Pharmacologic treatment for systolic heart failure, otherwise known as heart failure with reduced ejection fraction, has been established through clinical trials and is formulated into guidelines to standardize the diagnosis and treatment. The premise of pharmacologic therapy in heart failure with reduced ejection fraction is aimed primarily at interrupting the neurohormonal cascade that is responsible for altering left ventricular shape and function. This is the first in a series of articles to describe the pharmacologic agents in the guidelines that impact the morbidity and mortality associated with heart failure. Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and vasodilators will be presented in the context of the mechanism of action in heart failure, investigational trials that showed beneficial effects, and the practical application for clinical use.

  13. [What is new in heart failure with preserved ejection fraction within last five years?].

    PubMed

    Gregorová, Zdeňka; Meluzín, Jaroslav; Spinarová, Lenka

    2014-01-01

    Heart failure with preserved ejection fraction of left ventricle (heart failure with normal ejection fraction, HFPEF, HFNEF) is frequent disease with serious consequences. Incidence of HFPEF in population is still growing. The exact pathophysiological mechanism of HFPEF remain unclear .Recent evidence suggests a relationship between inflammation associated with obesity or Diabetes mellitus and progression of HFPEF. Consistently, it has been reported that serum concentration of some pro-inflammatory markers such as adiponectin is positively related to HFPEF. By HFPEF is attended diastolic dysfunction. Diastolic dysfunction is linked to many other cardiac and non-cardiac diseases. Despite the great effort and new therapeutic approaches the prognosis of HFPEF does not improve. The gold standard in HFPEF diagnosis remains heart catheterization. Electrocardiography, chest X-ray, blood examination including diagnostic markers of heart failure and mainly echocardiography with Doppler imaging are used diagnose the underlying disease leading to heart failure.

  14. Left ventricular volumes and ejection fraction derived from apical two-dimensional echocardiography

    PubMed Central

    Edelman, Sidney K.; Rowe, Dennis W.; Pechacek, Leonard W.; Garcia, Efrain

    1981-01-01

    Two-dimensional echocardiographic data in orthogonal apical projections were used to calculate left ventricular ejection fraction and volumes in 18 patients, 10 of whom had asynergy. The left ventricular chamber was modeled as a stack of 20 elliptical discs in order to minimize errors associated with assumptions of regular geometry. Calculations were compared to data from biplane angiography and yielded correlation coefficients of 0.91 for ejection fraction and 0.90 for volumes. The technique significantly underestimated volumes; the average ventricular volume was 161 ± 23 ml from cineangiography and 104 ± 25 ml from echocardiography (p < 0.001). Since this technique utilizes the most readily obtained echocardiographic views and allows for variations in ventricular architecture, its potential utility in long-term, serial evaluation of cardiac function appears promising. Images PMID:15216191

  15. Right ventricular ejection fraction: an indicator of increased mortality in patients with congestive heart failure associated with coronary artery disease

    SciTech Connect

    Polak, J.F.; Holman, B.L.; Wynne, J.; Colucci, W.S.

    1983-08-01

    The predictive value of radionuclide ventriculography was studied in 34 patients with depressed left ventricular ejection fraction (less than 40%) and clinically evident congestive heart failure secondary to atherosclerotic coronary artery disease. In addition to left ventricular ejection fraction, right ventricular ejection fraction and extent of left ventricular paradox were obtained in an attempt to identify a subgroup at increased risk of mortality during the ensuing months. The 16 patients who were alive after a 2 year follow-up period had a higher right ventricular ejection fraction and less extensive left ventricular dyskinesia. When a right ventricular ejection fraction of less than 35% was used as a discriminant, mortality was significantly greater among the 21 patients with a depressed right ventricular ejection fraction (71 versus 23%), a finding confirmed by a life table analysis. It appears that the multiple factors contributing to the reduction in right ventricular ejection fraction make it a useful index not only for assessing biventricular function, but also for predicting patient outcome.

  16. Nuclear cardiac ejection fraction and cardiac index in abdominal aortic surgery

    SciTech Connect

    Fiser, W.P.; Thompson, B.W.; Thompson, A.R.; Eason, C.; Read, R.C.

    1983-11-01

    Since atherosclerotic heart disease results in more than half of the perioperative deaths that follow abdominal aortic surgery, a prospective protocol was designed for preoperative evaluation and intraoperative hemodynamic monitoring. Twenty men who were prepared to undergo elective operation for aortoiliac occlusive disease (12 patients) and abdominal aortic aneurysm (eight patients) were evaluated with a cardiac scan and right heart catheterization. The night prior to operation, each patient received volume loading with crystalloid based upon ventricular performance curves. At the time of the operation, all patients were anesthetized with narcotics and nitrous oxide, and hemodynamic parameters were recorded throughout the operation. Aortic crossclamping resulted in a marked depression in CI in all patients. CI remained depressed after unclamping in the majority of patients. There were two perioperative deaths, both from myocardial infarction or failure. Both patients had ejection fractions less than 30% and initial CIs less than 2 L/M2, while the survivors' mean ejection fraction was 63% +/- 1 and their mean CI was 3.2 L/M2 +/- 0.6. The authors conclude that preoperative evaluation of ejection fraction can select those patients at a high risk of cardiac death from abdominal aortic operation. These patients should receive intensive preoperative monitoring with enhancement of ventricular performance.

  17. A porcine model of hypertensive cardiomyopathy: implications for heart failure with preserved ejection fraction.

    PubMed

    Schwarzl, Michael; Hamdani, Nazha; Seiler, Sebastian; Alogna, Alessio; Manninger, Martin; Reilly, Svetlana; Zirngast, Birgit; Kirsch, Alexander; Steendijk, Paul; Verderber, Jochen; Zweiker, David; Eller, Philipp; Höfler, Gerald; Schauer, Silvia; Eller, Kathrin; Maechler, Heinrich; Pieske, Burkert M; Linke, Wolfgang A; Casadei, Barbara; Post, Heiner

    2015-11-01

    Heart failure with preserved ejection fraction (HFPEF) evolves with the accumulation of risk factors. Relevant animal models to identify potential therapeutic targets and to test novel therapies for HFPEF are missing. We induced hypertension and hyperlipidemia in landrace pigs (n = 8) by deoxycorticosteroneacetate (DOCA, 100 mg/kg, 90-day-release subcutaneous depot) and a Western diet (WD) containing high amounts of salt, fat, cholesterol, and sugar for 12 wk. Compared with weight-matched controls (n = 8), DOCA/WD-treated pigs showed left ventricular (LV) concentric hypertrophy and left atrial dilatation in the absence of significant changes in LV ejection fraction or symptoms of heart failure at rest. The LV end-diastolic pressure-volume relationship was markedly shifted leftward. During simultaneous right atrial pacing and dobutamine infusion, cardiac output reserve and LV peak inflow velocities were lower in DOCA/WD-treated pigs at higher LV end-diastolic pressures. In LV biopsies, we observed myocyte hypertrophy, a shift toward the stiffer titin isoform N2B, and reduced total titin phosphorylation. LV superoxide production was increased, in part attributable to nitric oxide synthase (NOS) uncoupling, whereas AKT and NOS isoform expression and phosphorylation were unchanged. In conclusion, we developed a large-animal model in which loss of LV capacitance was associated with a titin isoform shift and dysfunctional NOS, in the presence of preserved LV ejection fraction. Our findings identify potential targets for the treatment of HFPEF in a relevant large-animal model.

  18. Comparison of characteristics and outcomes of patients with heart failure preserved ejection fraction versus reduced left ventricular ejection fraction in an urban cohort.

    PubMed

    Quiroz, Rene; Doros, Gheorghe; Shaw, Peter; Liang, Chang-Seng; Gauthier, Diane F; Sam, Flora

    2014-02-15

    Despite significant advances in therapies for patients with heart failure with reduced ejection fraction (HFrEF), there are no evidence-based therapies for heart failure with preserved ejection fraction (HFpEF), also known as diastolic heart failure (HF). Differences in pathophysiologic mechanisms are touted as to why patients with HFpEF purportedly do not derive similar therapeutic benefits compared with HFrEF. Similarly, the relative frequencies of HFpEF and HFrEF may differ between hospitalized and ambulatory settings. There are limited data on the prevalence, characteristics, treatment, and short-term outcomes of patients hospitalized with HFpEF. We sought to investigate these in patients hospitalized with HFpEF in an urban, hospitalized setting using the Get With The Guidelines registry. We retrospectively reviewed all consecutive discharges (n = 1,701) with a diagnosis of acute decompensated HF from December 1, 2006 to September 30, 2008. Patients with HFpEF (n = 499) were older, overweight, predominantly women, and had underlying hypertension and dyslipidemia. Presenting blood pressure and levels of creatinine were higher, with lower brain natriuretic peptide levels compared with patients with HFrEF (n = 598). Length of stay and 30-day mortality were comparable between patients with HFpEF and HFrEF. Thirty-day readmission was initially lower in patients with HFpEF. However 30-day mortality from any cause after the index HF hospitalization and survival curve at 1-year was no different between patients with HFpEF and HFrEF. In conclusion, lower 30-day readmissions do not translate into improved long-term outcome in patients with HFpEF.

  19. Heart Failure with Preserved Ejection Fraction - Concept, Pathophysiology, Diagnosis and Challenges for Treatment.

    PubMed

    Miljkovik, Lidija Veterovska; Spiroska, Vera

    2015-09-15

    Heart failure (HF) with preserved left ventricular (LV) ejection fraction (HFpEF) occurs in 40 to 60% of the patients with HF, with a prognosis which is similar to HF with reduced ejection fraction (HFrEF). HFpEF pathophysiology is different from that of HFrEF, and has been characterized with diastolic dysfunction. Diastolic dysfunction has been defined with elevated left ventricular stiffness, prolonged iso-volumetric LV relaxation, slow LV filing and elevated LV end-diastolic pressure. Arterial hypertension occurs in majority cases with HFpEF worldwide. Patients are mostly older and obese. Diabetes mellitus and atrial fibrillation appear proportionally in a high frequency of patients with HFpEF. The HFpEF diagnosis is based on existence of symptoms and signs of heart failure, normal or approximately normal ejection and diagnosing of LV diastolic dysfunction by means of heart catheterization or Doppler echocardiography and/or elevated concentration of plasma natriuretic peptide. The present recommendations for HFpEF treatment include blood pressure control, heart chamber frequency control when atrial fibrillation exists, in some situations even coronary revascularization and an attempt for sinus rhythm reestablishment. Up to now, it is considered that no medication or a group of medications improve the survival of HFpEF patients. Due to these causes and the bad prognosis of the disorder, rigorous control is recommended of the previously mentioned precipitating factors for this disorder. This paper presents a universal review of the most important parameters which determine this disorder.

  20. Right atrial volume by cardiovascular magnetic resonance predicts mortality in patients with heart failure with reduced ejection fraction

    PubMed Central

    Ivanov, Alexander; Mohamed, Ambreen; Asfour, Ahmed; Ho, Jean; Khan, Saadat A.; Chen, Onn; Klem, Igor; Ramasubbu, Kumudha; Brener, Sorin J.; Heitner, John F.

    2017-01-01

    Background Right Atrial Volume Index (RAVI) measured by echocardiography is an independent predictor of morbidity in patients with heart failure (HF) with reduced ejection fraction (HFrEF). The aim of this study is to evaluate the predictive value of RAVI assessed by cardiac magnetic resonance (CMR) for all-cause mortality in patients with HFrEF and to assess its additive contribution to the validated Meta-Analysis Global Group in Chronic heart failure (MAGGIC) score. Methods and results We identified 243 patients (mean age 60 ± 15; 33% women) with left ventricular ejection fraction (LVEF) ≤ 35% measured by CMR. Right atrial volume was calculated based on area in two- and four -chamber views using validated equation, followed by indexing to body surface area. MAGGIC score was calculated using online calculator. During mean period of 2.4 years 33 patients (14%) died. The mean RAVI was 53 ± 26 ml/m2; significantly larger in patients with than without an event (78.7±29 ml/m2 vs. 48±22 ml/m2, p<0.001). RAVI (per ml/m2) was an independent predictor of mortality [HR = 1.03 (1.01–1.04), p = 0.001]. RAVI has a greater discriminatory ability than LVEF, left atrial volume index and right ventricular ejection fraction (RVEF) (C-statistic 0.8±0.08 vs 0.55±0.1, 0.62±0.11, 0.68±0.11, respectively, all p<0.02). The addition of RAVI to the MAGGIC score significantly improves risk stratification (integrated discrimination improvement 13%, and category-free net reclassification improvement 73%, both p<0.001). Conclusion RAVI by CMR is an independent predictor of mortality in patients with HFrEF. The addition of RAVI to MAGGIC score improves mortality risk stratification. PMID:28369148

  1. Prognostic value of ejection fraction in patients admitted with acute coronary syndrome

    PubMed Central

    Perelshtein Brezinov, Olga; Klempfner, Robert; Zekry, Sagit Ben; Goldenberg, Ilan; Kuperstein, Rafael

    2017-01-01

    Abstract There are limited data regarding factors affecting outcomes among acute coronary syndrome (ACS) patients presenting with varying degrees of left ventricle (LV) dysfunction. We aimed to identify factors associated with mortality according to LV ejection fraction (LVEF) at 1st admission in ACS patients. A total of 8983 ACS patients prospectively enrolled in the Acute Coronary Syndrome Israeli Survey (2000–2010) were categorized according to their LVEF at admission: severe LV dysfunction (LVEF < 30% [n = 845]), mild-moderate LV dysfunction (LVEF 30%–49% [n = 4470]); preserved LV function (LVEF ≥ 50% [n = 3659]). Multivariable Cox proportional hazards regression modeling was used to assess the risk factors for 1-year mortality according to LVEF on admission. Over the past decade there was a gradual decline in the proportion of patients admitted with low LVEF. Mortality rates were highest among patients with severe LV dysfunction (36%), intermediate among those with mild-moderate LV dysfunction (10%), and lowest among those with preserved LV function (4%, P < 0.001). We recognized different risk factors for mortality according to LVEF at admission. Admission clinical features (syncope, anterior myocardial infarction, and ST elevation myocardial infarction [STEMI]) predicted mortality risk in patients with severe LV dysfunction (all P < 0.05), whereas the presence of comorbidities (hypertension, diabetes mellitus, chronic renal failure, and peripheral arterial disease) predicted mortality risk in patients with more preserved LV function. Age and admission Killip class ≥II were consistent predictors in all LVEF subsets. LVEF at admission is a strong predictor of mortality in ACS, and prognostic factors differ according to LVEF during admission. In patients with severe LV dysfunction signs of clinical instability are related to 1-year mortality; in patients with a more preserved LV function the prognosis is related to the

  2. Long-Term Survival for Patients with Acute Decompensated Heart Failure According to Ejection Fraction Findings

    PubMed Central

    Coles, Andrew H.; Fisher, Kimberly; Darling, Chad; Yarzebski, Jorge; McManus, David D.; Gore, Joel M.; Lessard, Darleen; Goldberg, Robert J.

    2014-01-01

    Limited data exists about the long-term prognosis of patients with acute decompensated heart failure (ADHF) further stratified according to ejection fraction (EF) findings. The primary objective of this population-based observational study was to characterize and compare trends in long-term prognosis after an episode of ADHF across 3 EF strata. Hospital medical records were reviewed for 3,604 residents of the Worcester (MA) metropolitan area who were discharged after ADHF from all 11 medical centers in central Massachusetts during 1995, 2000, 2002, and 2004 and had EF measurements during their index hospitalization. The average age of this population was 75 years, the majority was white, and 44% were men. Approximately 49% of the population had preserved EF HF (HF-PEF) (≥50%), 37% had reduced EF HF (HF-REF) (<40%), and 14% had borderline EF HF (41-49%) (HF-BREF). Patients with HF-PEF experienced higher post discharge survival rates than patients with either HF-REF or HF-BREF at 1, 2, and 5-years after discharge from all central Massachusetts medical centers. While prognosis at 1-year after hospital discharge improved for all patient groups during the years under study, especially for those with HF-REF and HF-PEF, these encouraging trends declined with increasing duration of follow-up. In conclusion, although improvements in 1-year post-discharge survival were observed for patients in each of the 3 EF groups examined to varying degrees, the post-discharge prognosis of all patients with ADHF remains guarded. PMID:25092194

  3. Hemodynamic responses to small muscle mass exercise in heart failure patients with reduced ejection fraction.

    PubMed

    Barrett-O'Keefe, Zachary; Lee, Joshua F; Berbert, Amanda; Witman, Melissa A H; Nativi-Nicolau, Jose; Stehlik, Josef; Richardson, Russell S; Wray, D Walter

    2014-11-15

    To better understand the mechanisms responsible for exercise intolerance in heart failure with reduced ejection fraction (HFrEF), the present study sought to evaluate the hemodynamic responses to small muscle mass exercise in this cohort. In 25 HFrEF patients (64 ± 2 yr) and 17 healthy, age-matched control subjects (64 ± 2 yr), mean arterial pressure (MAP), cardiac output (CO), and limb blood flow were examined during graded static-intermittent handgrip (HG) and dynamic single-leg knee-extensor (KE) exercise. During HG exercise, MAP increased similarly between groups. CO increased significantly (+1.3 ± 0.3 l/min) in the control group, but it remained unchanged across workloads in HFrEF patients. At 15% maximum voluntary contraction (MVC), forearm blood flow was similar between groups, while HFrEF patients exhibited an attenuated increase at the two highest intensities compared with controls, with the greatest difference at the highest workload (352 ± 22 vs. 492 ± 48 ml/min, HFrEF vs. control, 45% MVC). During KE exercise, MAP and CO increased similarly across work rates between groups. However, HFrEF patients exhibited a diminished leg hyperemic response across all work rates, with the most substantial decrement at the highest intensity (1,842 ± 64 vs. 2,675 ± 81 ml/min; HFrEF vs. control, 15 W). Together, these findings indicate a marked attenuation in exercising limb perfusion attributable to impairments in peripheral vasodilatory capacity during both arm and leg exercise in patients with HFrEF, which likely plays a role in limiting exercise capacity in this patient population.

  4. Relation of Pre-anthracycline Serum Bilirubin Levels to Left Ventricular Ejection Fraction After Chemotherapy.

    PubMed

    Vera, Trinity; D'Agostino, Ralph B; Jordan, Jennifer H; Whitlock, Matthew C; Meléndez, Giselle C; Lamar, Zanetta S; Porosnicu, Mercedes; Bonkovsky, Herbert L; Poole, Leslie B; Hundley, W Gregory

    2015-12-01

    Myocardial injury because of oxidative stress manifesting through reductions in left ventricular ejection fraction (LVEF) may occur after the administration of anthracycline-based chemotherapy (A-bC). We hypothesized that bilirubin, an effective endogenous antioxidant, may attenuate the reduction in LVEF that sometimes occurs after receipt of A-bC. We identified 751 consecutively treated patients with cancer who underwent a pre-A-bC LVEF measurement, exhibited a serum total bilirubin level <2 mg/dl, and then received a post-A-bC LVEF assessment because of symptomatology associated with heart failure. Analysis of variance, Tukey's Studentized range test, and chi-square tests were used to evaluate an association between bilirubin and LVEF changes. The LVEF decreased by 10.7 ± 13.7%, 8.9 ± 11.8%, and 7.7 ± 11.5% in group 1 (bilirubin at baseline ≤0.5 mg/dl), group 2 (bilirubin 0.6 to 0.8 mg/dl), and group 3 (bilirubin 0.9 to 1.9 mg/dl), respectively. More group 1 patients experienced >15% decrease in LVEF compared with those in group 3 (p = 0.039). After adjusting for age, coronary artery disease/myocardial infarction, diabetes mellitus, hematocrit, and the use of cardioactive medications, higher precancer treatment bilirubin levels and lesser total anthracycline doses were associated with LVEF preservation (p = 0.047 and 0.011, respectively). In patients treated with anthracyclines who subsequently develop symptoms associated with heart failure, pre-anthracycline treatment serum bilirubin levels inversely correlate with subsequent deterioration in post-cancer treatment LVEF. In conclusion, these results suggest that increased levels of circulating serum total bilirubin, an intrinsic antioxidant, may facilitate preservation of LVEF in patients receiving A-bC for cancer.

  5. Prognostic value of ejection fraction in patients admitted with acute coronary syndrome: A real world study.

    PubMed

    Perelshtein Brezinov, Olga; Klempfner, Robert; Zekry, Sagit Ben; Goldenberg, Ilan; Kuperstein, Rafael

    2017-03-01

    There are limited data regarding factors affecting outcomes among acute coronary syndrome (ACS) patients presenting with varying degrees of left ventricle (LV) dysfunction. We aimed to identify factors associated with mortality according to LV ejection fraction (LVEF) at 1st admission in ACS patients.A total of 8983 ACS patients prospectively enrolled in the Acute Coronary Syndrome Israeli Survey (2000-2010) were categorized according to their LVEF at admission: severe LV dysfunction (LVEF < 30% [n = 845]), mild-moderate LV dysfunction (LVEF 30%-49% [n = 4470]); preserved LV function (LVEF ≥ 50% [n = 3659]). Multivariable Cox proportional hazards regression modeling was used to assess the risk factors for 1-year mortality according to LVEF on admission.Over the past decade there was a gradual decline in the proportion of patients admitted with low LVEF. Mortality rates were highest among patients with severe LV dysfunction (36%), intermediate among those with mild-moderate LV dysfunction (10%), and lowest among those with preserved LV function (4%, P < 0.001). We recognized different risk factors for mortality according to LVEF at admission. Admission clinical features (syncope, anterior myocardial infarction, and ST elevation myocardial infarction [STEMI]) predicted mortality risk in patients with severe LV dysfunction (all P < 0.05), whereas the presence of comorbidities (hypertension, diabetes mellitus, chronic renal failure, and peripheral arterial disease) predicted mortality risk in patients with more preserved LV function. Age and admission Killip class ≥II were consistent predictors in all LVEF subsets.LVEF at admission is a strong predictor of mortality in ACS, and prognostic factors differ according to LVEF during admission. In patients with severe LV dysfunction signs of clinical instability are related to 1-year mortality; in patients with a more preserved LV function the prognosis is related to the presence of co-morbidities.

  6. Assessment of left ventricular ejection fraction by radionuclide angiography. Comparison to echocardiography and serial measurements in patients with myocardial infarction

    NASA Technical Reports Server (NTRS)

    Schelbert, H. R.; Henning, H.; Orourke, R. A.; Ashburn, W. L.

    1975-01-01

    Measurements of the left ventricular ejection fraction were compared in patients with previous myocardial infarctions. Left ventricular ejection fraction was measured by the radioisotopic method serially in patients early after an acute myocardial infarction and during the convalescence period. Ultrasound recordings were obtained utilizing a commercially available ultrasonoscope and a 1/9 cm transducer focused at 10 cm with a repetition rate of 1000 impulses per second. All recordings were made on a visicorder oscillography.

  7. Time-Dependent Regional Myocardial Strains in Patients with Heart Failure with a Preserved Ejection Fraction

    PubMed Central

    Smith, Shane P.; Secomb, Timothy W.; Hong, Brian D.; Moulton, Michael J.

    2016-01-01

    Objectives. To better understand the etiology of HFpEF in a controlled human population, regional time-varying strains were computed using echocardiography speckle tracking in patients with heart failure with a preserved ejection fraction and normal subjects. Methods. Eleven normal volunteers and ten patients with echo-graded diastolic dysfunction and symptoms of heart failure were imaged with echocardiography and longitudinal, circumferential, and rotational strains were determined using speckle-tracking. Diastolic strain rate was also determined. Patient demographics and echo-derived flows, volumes, and pressures were recorded. Results. Peak longitudinal and circumferential strain was globally reduced in patients (p < 0.001), when compared to controls. The patients attained peak longitudinal and circumferential strain at a consistently later point in systole than controls. Rotational strains were not different in most LV regions. Early diastolic strain rate was significantly reduced in the patients (p < 0.001). LV mass and wall thickness were significantly increased in the patients; however ejection fraction was preserved and stroke volume was diminished (p < 0.001). Conclusions. This study shows that patients with HFpEF have reduced early diastolic strain rate and reduced peak strain that is regionally homogeneous and that they also utilize a longer fraction of systole to achieve peak axial strains. PMID:27042673

  8. Normal Gallbladder Ejection Fraction Occurring Unexpectedly Obviates Need for Sincalide Stimulation.

    PubMed

    Hadi, Samir; Tulchinsky, Mark

    2017-02-17

    A 25-year-old man was referred for chronic right upper quadrant abdominal pain for hepatobiliary scintigraphy to evaluate the gallbladder (GB) function. An unexpected GB contraction with ejection fraction (EF) of 90% was observed during the first hour of baseline imaging. Subsequent stimulation with sincalide produced GB EF of 99%. A similar case previously reported also showed normal unexpected GB EF that predicted similar post-sincalide GB EF. These examples support what should be evident: A normal unexpected GB EF is a sufficient evidence for a normal GB function and should obviate need for sincalide stimulation.

  9. Neprilysin Inhibition in Heart Failure with Reduced Ejection Fraction: A Clinical Review.

    PubMed

    King, Jordan B; Bress, Adam P; Reese, Austin D; Munger, Mark A

    2015-09-01

    There has been a 10-year hiatus in the approval of a new pharmacotherapy for patients with chronic heart failure with a reduced ejection fraction (HFrEF). Combining an angiotensin receptor blocker, valsartan, with sacubitril, an inhibitor of neprilysin, results in increasing levels of natriuretic peptides that counterbalance high circulating levels of neurohormones in HFrEF. This has resulted in the development of a new agent, LCZ696. A comprehensive overview of LCZ696, its pharmacology, its role in the pathophysiology of HFrEF, completed and future clinical trial information, specific critical issues, and the place of LCZ696 in HFrEF therapy are presented.

  10. Cholecystokinin enhanced hepatobiliary scanning with ejection fraction calculation as an indicator of disease of the gallbladder

    SciTech Connect

    Zech, E.R.; Simmons, L.B.; Kendrick, R.R.; Soballe, P.W.; Olcese, J.A.; Goff, W.B. II; Lawrence, D.P.; DeWeese, R.A. )

    1991-01-01

    Chronic acalculous cholecystitis represents 5 to 20 per cent of electively treated diseases of the gallbladder. A 70 per cent success rate in relieving these patients of chronic pain was reported when surgical treatment was recommended based on symptoms alone. The cholecystokinin ejection fraction, which is a quantitative measure of emptying of the gallbladder, was 95 per cent accurate in predicting which patients would be relieved of symptoms by surgical treatment. In this study, we report our consecutive experience during a 20 month period with 83 patients.

  11. The sympathetic/parasympathetic imbalance in heart failure with reduced ejection fraction

    PubMed Central

    Floras, John S.; Ponikowski, Piotr

    2015-01-01

    Cardiovascular autonomic imbalance, a cardinal phenotype of human heart failure, has adverse implications for symptoms during wakefulness and sleep; for cardiac, renal, and immune function; for exercise capacity; and for lifespan and mode of death. The objectives of this Clinical Review are to summarize current knowledge concerning mechanisms for disturbed parasympathetic and sympathetic circulatory control in heart failure with reduced ejection fraction and its clinical and prognostic implications; to demonstrate the patient-specific nature of abnormalities underlying this common phenotype; and to illustrate how such variation provides opportunities to improve or restore normal sympathetic/parasympathetic balance through personalized drug or device therapy. PMID:25975657

  12. Challenging aspects of treatment strategies in heart failure with preserved ejection fraction: “Why did recent clinical trials fail?”

    PubMed Central

    Becher, Peter Moritz; Fluschnik, Nina; Blankenberg, Stefan; Westermann, Dirk

    2015-01-01

    Heart failure (HF) is the leading cause of hospitalization among older adults and the prevalence is growing with the aging populations in the Western countries. Epidemiologic reports suggest that approximately 50% of patients who have signs or symptoms of HF have preserved left ventricular ejection fraction. This HF type predominantly affects women and the elderly with other co-morbidities, such as diabetes, hypertension, and overt volume status. Most of the current treatment strategies are based on morbidity benefits such as quality of life and reduction of clinical HF symptoms. Treatment of patients with HF with preserved ejection fraction displayed disappointing results from several large randomized controlled trials. The heterogeneity of HF with preserved ejection fraction, understood as complex syndrome, seems to be one of the primary reasons. Here, we present an overview of the current management strategies with available evidence and new therapeutic approach from drugs currently in clinical trials, which target diastolic dysfunction, chronotropic incompetence, and risk factor management. We provide an outline and interpretation of recent clinical trials that failed to improve outcome and survival in patients with HF with preserved ejection fraction. PMID:26413231

  13. The Shergottite Age Paradox and the Relative Probabilities of Ejecting Martian Meteorites of Differing Ages

    NASA Technical Reports Server (NTRS)

    Borg, L. E.; Shih, C.-Y.; Nyquist, L. E.

    1998-01-01

    The apparent paradox that the majority of impacts yielding Martian meteorites appear to have taken place on only a few percent of the Martian surface can be resolved if all the shergottites were ejected in a single event rather than in multiple events as expected from variations in their cosmic ray exposure and crystallization ages. If the shergottite-ejection event is assigned to one of three craters in the vicinity of Olympus Mons that were previously identified as candidate source craters for the SNC (Shergottites, Nakhlites, Chassigny) meteorites, and the nakhlite event to another candidate crater in the vicinity of Ceraunius Tholus, the implied ages of the surrounding terranes agree well with crater density ages. EN,en for high cratering rates (minimum ages), the likely origin of the shergottites is in the Tharsis region, and the paradox of too many meteorites from too little terrane remains for multiple shergottite-ejection events. However, for high cratering rates it is possible to consider sources for the nakhlltes which are away from the Tharsis region. The meteorite-yielding impacts may have been widely dispersed with sources of the young SNC meteorites in the northern plains, and the source of the ancient orthopyroxenite, ALH84001, in the ancient southern uplands. Oblique-impact craters can be identified with the sources of the nakhlites and the orthopyroxenite,, respectively, in the nominal cratering rate model, and with the shergottites and orthopyroxenite, respectively, in the high cratering rate model. Thus, oblique impacts deserve renewed attention as an ejection mechanism for Martian meteorites.

  14. Heart failure with preserved ejection fraction: Defining the function of ROS and NO.

    PubMed

    Zuo, Li; Chuang, Chia-Chen; Hemmelgarn, Benjamin T; Best, Thomas M

    2015-10-15

    The understanding of complex molecular mechanisms underlying heart failure (HF) is constantly under revision. Recent research has paid much attention to understanding the growing number of patients that exhibit HF symptoms yet have an ejection fraction similar to a normal phenotype. Termed heart failure with preserved ejection fraction (HFpEF), this novel hypothesis traces its roots to a proinflammatory state initiated in part by the existence of comorbidities that create a favorable environment for the production of reactive oxygen species (ROS). Triggering a cascade that involves reduced nitric oxide (NO) availability, elevated ROS levels in the coronary endothelium eventually contribute to hypertrophy and increased resting tension in cardiomyocytes. Improved understanding of the molecular pathways associated with HFpEF has led to studies that concentrate on reducing ROS production in the heart, boosting NO availability, and increasing exercise capacity for HFpEF patients. This review will explore the latest research into the role of ROS and NO in the progression of HFpEF, as well as discuss the encouraging results of numerous therapeutic studies.

  15. Facts and numbers on epidemiology and pharmacological treatment of heart failure with preserved ejection fraction

    PubMed Central

    2015-01-01

    Abstract Heart failure with preserved ejection fraction (HFpEF) is a major and growing public health problem. Epidemiologic studies demonstrated that heart failure (HF) can be clinically diagnosed in patients with normal or preserved left ventricular ejection fraction. These patients are therefore termed as having HFpEF. In the past, this was often called diastolic HF. Because of the permanent increase of the prevalence of HFpEF during the past decades, HFpEF now accounts for more than 50% of the total HF population. There are uncertainties and debates regarding the definition, diagnosis, and pathophysiology with the consequence that all outcome trials performed so far used criteria for inclusion and exclusion that were not consistent. These trials also failed to document improved prognosis. Recent smaller proof‐of‐concept or Phase II clinical trials investigating different pathophysiological approaches with substances such as the neprilysin inhibitor–angiotensin receptor blocker− combination (LCZ 696), ranolazine, or ivabradine were successful to improve biomarkers, haemodynamics, or functional capacity. Future trials will need to document whether also prognosis can be improved. PMID:27708850

  16. Understanding heart failure with preserved ejection fraction: where are we today?

    PubMed

    van Heerebeek, L; Paulus, W J

    2016-04-01

    Heart failure with preserved ejection fraction (HFpEF) represents a complex and heterogeneous clinical syndrome, which is increasingly prevalent and associated with poor outcome. In contrast to heart failure with reduced ejection fraction (HFrEF), modern heart failure pharmacotherapy did not improve outcome in HFpEF, which was attributed to incomplete understanding of HFpEF pathophysiology, patient heterogeneity and lack of insight into primary pathophysiological processes. HFpEF patients are frequently elderly females and patients demonstrate a high prevalence of non-cardiac comorbidities, which independently adversely affect myocardial structural and functional remodelling. Furthermore, although diastolic left ventricular dysfunction represents the dominant abnormality in HFpEF, numerous ancillary mechanisms are frequently present, which also negatively impact on cardiovascular reserve. Over the past decade, clinical and translational research has improved insight into HFpEF pathophysiology and the importance of comorbidities and patient heterogeneity. Recently, a new paradigm for HFpEF was proposed, which states that comorbidities drive myocardial dysfunction and remodelling in HFpEF through coronary microvascular inflammation. Regarding the conceptual framework of HFpEF treatment, emphasis may need to shift from a 'one fits all' strategy to an individualised approach based on phenotypic patient characterisation and diagnostic and pathophysiological stratification of myocardial disease processes. This review will describe these novel insights from a pathophysiological standpoint.

  17. Response of left ventricular ejection fraction to recovery from general anesthesia: measurement by gated radionuclide angiography

    SciTech Connect

    Coriat, P.; Mundler, O.; Bousseau, D.; Fauchet, M.; Rous, A.C.; Echter, E.; Viars, P.

    1986-06-01

    To test the hypothesis that, after anesthesia for noncardiac surgical procedures, the increased cardiac work during recovery induces wall motion and ejection fraction (EF) abnormalities in patients with mild angina pectoris, gated radionuclide angiography was performed in patients undergoing simple cholecystectomy under narcotic-relaxant general anesthesia. The ejection fraction was determined during anesthesia at the end of surgery, and then determined 3 min and 3 hr after extubation. A new angiography was performed 24 hr later, and a myocardial scintigraphy (Thallium 201) was performed during infusion of the coronary vasodilator, dipyridamole. In the first part of the investigation, eight patients without coronary artery disease (CAD) (group 1) and 20 patients with mild angina (group 2) were studied. In the second part of the study, seven patients (group 3) with mild angina pectoris received an intravenous infusion of 0.4 microgram X kg-1 X min-1 of nitroglycerin started before surgery and gradually decreased 4 hr after extubation. In group 1, EF remained unchanged at recovery. In contrast in group 2, EF responded abnormally to recovery: EF decreased from 55% during anesthesia to 45% 3 min after extubation (P less than 0.001). Patients in group 3, who received intravenous nitroglycerin, showed no change of EF at recovery. This study demonstrates that recovery from general anesthesia causes abnormalities in left ventricular function in patients suffering from CAD. These abnormalities are prevented by prophylactic intravenous nitroglycerin.

  18. Facts and numbers on epidemiology and pharmacological treatment of heart failure with preserved ejection fraction.

    PubMed

    Edelmann, Frank

    2015-06-01

    Heart failure with preserved ejection fraction (HFpEF) is a major and growing public health problem. Epidemiologic studies demonstrated that heart failure (HF) can be clinically diagnosed in patients with normal or preserved left ventricular ejection fraction. These patients are therefore termed as having HFpEF. In the past, this was often called diastolic HF. Because of the permanent increase of the prevalence of HFpEF during the past decades, HFpEF now accounts for more than 50% of the total HF population. There are uncertainties and debates regarding the definition, diagnosis, and pathophysiology with the consequence that all outcome trials performed so far used criteria for inclusion and exclusion that were not consistent. These trials also failed to document improved prognosis. Recent smaller proof-of-concept or Phase II clinical trials investigating different pathophysiological approaches with substances such as the neprilysin inhibitor-angiotensin receptor blocker- combination (LCZ 696), ranolazine, or ivabradine were successful to improve biomarkers, haemodynamics, or functional capacity. Future trials will need to document whether also prognosis can be improved.

  19. Diastolic function is associated with quality of life and exercise capacity in stable heart failure patients with reduced ejection fraction

    PubMed Central

    Bussoni, M.F.; Guirado, G.N.; Roscani, M.G.; Polegato, B.F.; Matsubara, L.S.; Bazan, S.G.Z.; Matsubara, B.B.

    2013-01-01

    Exercise capacity and quality of life (QOL) are important outcome predictors in patients with systolic heart failure (HF), independent of left ventricular (LV) ejection fraction (LVEF). LV diastolic function has been shown to be a better predictor of aerobic exercise capacity in patients with systolic dysfunction and a New York Heart Association (NYHA) classification ≥II. We hypothesized that the currently used index of diastolic function E/e' is associated with exercise capacity and QOL, even in optimally treated HF patients with reduced LVEF. This prospective study included 44 consecutive patients aged 55±11 years (27 men and 17 women), with LVEF<0.50 and NYHA functional class I-III, receiving optimal pharmacological treatment and in a stable clinical condition, as shown by the absence of dyspnea exacerbation for at least 3 months. All patients had conventional transthoracic echocardiography and answered the Minnesota Living with HF Questionnaire, followed by the 6-min walk test (6MWT). In a multivariable model with 6MWT as the dependent variable, age and E/e' explained 27% of the walked distance in 6MWT (P=0.002; multivariate regression analysis). No association was found between walk distance and LVEF or mitral annulus systolic velocity. Only normalized left atrium volume, a sensitive index of diastolic function, was associated with decreased QOL. Despite the small number of patients included, this study offers evidence that diastolic function is associated with physical capacity and QOL and should be considered along with ejection fraction in patients with compensated systolic HF. PMID:24036912

  20. Assessment of the Relationship between Galectin-3 and Ejection Fraction and Functional Capacity in the Patients with Compensated Systolic Heart Failure

    PubMed Central

    Atabakhshian, Roya; Kazerouni, Faranak; Raygan, Fariba; Amirrasouli, Hushang; Rahimipour, Ali; Shakeri, Nezhat

    2014-01-01

    Background: Galectin-3 is a soluble ß-galactoside–binding lectin released by activated cardiac macrophages. Galectin-3 has been proposed for diagnosis and prognosis of HF patients. Objectives: The present study aimed to investigate the relationship between galectin-3 as a biomarker and ejection fraction and functional capacity in the patients with compensated systolic heart failure. Patients and Methods: In this study, serum levels of Galectin-3 were measured in 76 patients with compensated heart failure with New York Heart Association class I–IV and left ventricular ejection fraction < 45%. Galectin-3 was measured by an ELISA kit. Besides, echocardiography was used to evaluate left ventricular ejection fraction. Additionally, functional capacity was determined based on the patients’ ability to perform a set of activities. After all, the data were analyzed used t-test, Kruskal-Wallis, one–way ANOVA, and chi-square test. P < 0.05 was considered as statistically significant. Results: The patients’ age ranged from 45 to 75 years, with the mean age of 63.85 ± 9 years. In addition 57.9% of the patients were male. The results revealed no significant correlation between Galectin-3 and age, body mass index, and estimated glomerular filtration rate. Also, no significant correlation was observed between Galectin-3 levels and left ventricular ejection fraction (P = 0.166) and functional capacity (P = 0.420). Yet, a significant difference was found between males and females regarding the mean of Galectin-3 (P = 0.039). Conclusions: The study results suggested that Galectin-3 could not be used as a marker of disease progression in the patients under treatment, which could probably be the result of medication use in these patients. PMID:25614856

  1. A Practical Guide for the Treatment of Symptomatic Heart Failure with Reduced Ejection Fraction (HFrEF)

    PubMed Central

    Reed, Brent N; Sueta, Carla A

    2015-01-01

    This review will outline the management of patients with symptomatic systolic heart failure or heart failure with reduced ejec-tion fraction (HFrEF), i.e., those with structural heart disease and previous or current symptoms. Determination of volume status and appropriate diuretic administration is important in heart failure management. Inhibition of the renin-angiotensin-aldosterone and sympathetic nervous systems improves survival and decreases hospitalizations in patients with systolic or reduced ejection fraction HF (HFrEF). Beta blockers and aldosterone antagonists improve ejection fraction. Indications for additional agents including nitrates plus hydralazine, digoxin, statins, omega 3 polyunsaturated fatty acids, anticoagulants, and antiarrhythmics will be discussed. Choice of agents, dose-related effects, strategies to minimize adverse effects, and medications to avoid will be presented. PMID:24251455

  2. Transthyretin Cardiac Amyloidosis: Pathogenesis, Treatments, and Emerging Role in Heart Failure with Preserved Ejection Fraction

    PubMed Central

    Ton, Van-Khue; Mukherjee, Monica; Judge, Daniel P

    2014-01-01

    Transthyretin (TTR) amyloidosis causes heart failure from cardiac deposition of TTR amyloid fibrils, the by-product of TTR homotetramer disassembly. Wild-type (WT) TTR deposition leads to senile amyloidosis, predominantly manifesting with cardiomyopathy. Missense mutations in the TTR gene result in familial TTR amyloidosis. Certain mutations are more likely to affect the heart, while others cause more neurologic involvement. Extracellular fibril deposition triggers intracellular stress response, upregulation of the inflammatory cascades, apoptosis, and organ dysfunction. Recent studies suggest that TTR cardiac amyloid may be a significant contributor to the pathogenesis of heart failure with preserved ejection fraction (HFpEF). Summarized in this review are the molecular pathways underlying the cellular toxicity of TTR amyloid fibrils and the emerging therapies aimed at TTR tetramer stabilization, abrogation of TTR synthesis in the liver, or inhibition of amyloidogenesis. PMID:25628512

  3. Pioglitazone-induced congestive heart failure and pulmonary edema in a patient with preserved ejection fraction

    PubMed Central

    Jearath, Vaneet; Vashisht, Rajan; Rustagi, Vipul; Raina, Sujeet; Sharma, Rajesh

    2016-01-01

    Pioglitazone-induced heart failure is known in patients with underlying heart disease, but is not well documented in patients with normal left ventricular function. Pioglitazone has been very popular as it is an insulin sensitizer and insulin resistance is prevalent among Indians. Fluid retention exacerbates pre-existing heart failure or precipitates heart failure in a patient with underlying left ventricular dysfunction. However, pathogenesis of heart failure in a patient with normal left ventricular function is not known. Probably it is due to dose-related effect on pulmonary endothelial permeability, rather than alterations in left ventricular mass or ejection fraction. We report a patient who developed congestive heart failure and pulmonary edema with normal left ventricular function within 1 year of starting pioglitazone therapy. We have to be careful in monitoring all possible side effects during followup when patients are on pioglitazone therapy. PMID:27127397

  4. [Isotope angiocardiography: amelioration of the measurement of ejection fraction by a new treatment of the image].

    PubMed

    Widmann, T; Righetti, A; de Lorgeril, M; Soulier, B; Brandon, G; Fournet, P C

    1981-11-07

    Some of the limitations affecting radioisotopic images are their insufficient resolution, structure boundaries and accurate subtraction of background noise. In order to improve the signal-to-noise ratio the images of the recorded heart cycles are treated by the Karhunen-Loeve transformation. Edge detection is based on compression of the image to a bitmap at a chosen level and following of all bits set to one by a pointer. The outlines of the structures as determined by edge tracking are used to define the regions of interest within the enhanced images. Background subtraction applies the principle of interpolative background subtraction by computing an individual background for each point in an irregular region of interest. The resultant images are used to calculate an index of cardiac efficiency which shows high correlation (r = 0.92) with the ejection fraction of contrast biplane left ventricular angiography.

  5. Treatment of Heart Failure With Reduced Ejection Fraction-Recent Developments.

    PubMed

    Travessa, André Miguel Ramos; de Menezes Falcão, Luiz Filipe

    2016-01-01

    Heart failure with reduced ejection fraction (HFrEF) represents at least half of the cases of heart failure, which is a syndrome defined as the inability of the heart to supply the body's tissues with an adequate amount of blood under conditions of normal cardiac filling pressure. HFrEF is responsible for high costs and rates of mortality, morbidity, and hospital admissions, mainly in developed countries. Thus, the need for better diagnostic methods and therapeutic approaches and consequently better outcomes is clear. In this article, we review the principal aspects of pathophysiology and diagnosis of HFrEF, with focus on emerging biomarkers and on recent echocardiographic methods for the assessment of left ventricular function. Furthermore, we discuss several major developments in pharmacological and nonpharmacological treatment of HFrEF in the last years, including cardiac resynchronization therapy, implantable cardioverter defibrillators, and the recent and promising drug LCZ696, focusing on current indications, unanswered questions, and other relevant aspects.

  6. Epidemiology of "Heart Failure with Recovered Ejection Fraction": What do we do After Recovery?

    PubMed

    Kuttab, Johny S; Kiernan, Michael S; Vest, Amanda R

    2015-12-01

    Improvement in functional status, long-term survival, and quality of life has always been the goal of therapy in patients with heart failure with reduced ejection fraction. Neurohormonal modulating medications help patients achieve these goals and, in a subgroup of patients, can promote "reverse remodeling" resulting in the recovery of left ventricular systolic function. In the era of durable mechanical support, myocardial recovery that leads to explantation of the ventricular assist device occurs in a minority of cases. Optimal medical therapy appears to be a key component of achieving myocardial recovery, with recovery more likely in patients with a shorter duration of heart failure and a non-ischemic etiology. However, little is known about future management of patients who attain myocardial recovery, either with or without mechanical support. This review explores the epidemiology, physiology, cellular biology, and long-term outcomes for this subgroup of heart failure patients and outlines areas for future study.

  7. Determination of right ventricular ejection fraction in children with cystic fibrosis

    SciTech Connect

    Piepsz, A.; Ham, H.R.; Millet, E.; Dab, I.

    1987-01-01

    The radionuclide right ventricular ejection fraction (RVEF) determined by means of Krypton-81m represents a simple, noninvasive, and accurate procedure to quantify the right ventricular contractility. This procedure was applied to 25 young patients with cystic fibrosis. The RVEF tended to decrease with the progression of the lung disease, as assessed by the clinical S-K score, the degree of the defects on lung scintigraphy, the PaO/sub 2/, and the lung function tests. However, the decrease of RVEF in patients with marked lung function tests. However, the decrease of RVEF in patients with marked lung involvement was moderate, and terminal lung disease was sometimes associated with normal right heart contractility.

  8. Pioglitazone-induced congestive heart failure and pulmonary edema in a patient with preserved ejection fraction.

    PubMed

    Jearath, Vaneet; Vashisht, Rajan; Rustagi, Vipul; Raina, Sujeet; Sharma, Rajesh

    2016-01-01

    Pioglitazone-induced heart failure is known in patients with underlying heart disease, but is not well documented in patients with normal left ventricular function. Pioglitazone has been very popular as it is an insulin sensitizer and insulin resistance is prevalent among Indians. Fluid retention exacerbates pre-existing heart failure or precipitates heart failure in a patient with underlying left ventricular dysfunction. However, pathogenesis of heart failure in a patient with normal left ventricular function is not known. Probably it is due to dose-related effect on pulmonary endothelial permeability, rather than alterations in left ventricular mass or ejection fraction. We report a patient who developed congestive heart failure and pulmonary edema with normal left ventricular function within 1 year of starting pioglitazone therapy. We have to be careful in monitoring all possible side effects during followup when patients are on pioglitazone therapy.

  9. Diagnosis and Management of Heart Failure with Preserved Ejection Frac-tion: 10 Key Lessons

    PubMed Central

    A, Afşin Oktay; Shah, Sanjiv J

    2015-01-01

    Heart failure with preserved ejection fraction (HFpEF) is a common clinical syndrome associated with high rates of morbidi-ty and mortality. Due to the lack of evidence-based therapies and increasing prevalence of HFpEF, clinicians are often con-fronted with these patients and yet have little guidance on how to effectively diagnose and manage them. Here we offer 10 key lessons to assist with the care of patients with HFpEF: (1) Know the difference between diastolic dysfunction, diastolic heart failure, and HFpEF; (2) diagnosing HFpEF is challenging, so be thorough and consider invasive hemodynamic testing to confirm the diagnosis; (3) a normal B-type natriuretic peptide does not exclude the diagnosis of HFpEF; (4) elevated pul-monary artery systolic pressure on echocardiography in the presence of a normal ejection fraction should prompt considera-tion of HFpEF; (5) use dynamic testing in evaluating the possibility of HFpEF in patients with unexplained dyspnea or exer-cise tolerance; (6) all patients with HFpEF should be systematically evaluated for the presence of coronary artery disease; (7) use targeted treatment for HFpEF patients based on their phenotypic classification; (8) treat HFpEF patients now by treating their comorbidities; (9) understand the importance of heart rate in HFpEF—lower is not always better; and (10) do not forget to consider rare diseases (“zebras”) as causes for HFpEF when evaluating and treating patients. Taken together, these 10 key lessons can help clinicians care for challenging patients with HFpEF while we eagerly await the results of ongoing HFpEF clinical trials and observational studies. PMID:24251461

  10. Diagnosis and management of heart failure with preserved ejection fraction: 10 key lessons.

    PubMed

    Oktay, A Afşin; Shah, Sanjiv J

    2015-01-01

    Heart failure with preserved ejection fraction (HFpEF) is a common clinical syndrome associated with high rates of morbidity and mortality. Due to the lack of evidence-based therapies and increasing prevalence of HFpEF, clinicians are often confronted with these patients and yet have little guidance on how to effectively diagnose and manage them. Here we offer 10 key lessons to assist with the care of patients with HFpEF: (1) Know the difference between diastolic dysfunction, diastolic heart failure, and HFpEF; (2) diagnosing HFpEF is challenging, so be thorough and consider invasive hemodynamic testing to confirm the diagnosis; (3) a normal B-type natriuretic peptide does not exclude the diagnosis of HFpEF; (4) elevated pulmonary artery systolic pressure on echocardiography in the presence of a normal ejection fraction should prompt consideration of HFpEF; (5) use dynamic testing in evaluating the possibility of HFpEF in patients with unexplained dyspnea or exercise tolerance; (6) all patients with HFpEF should be systematically evaluated for the presence of coronary artery disease; (7) use targeted treatment for HFpEF patients based on their phenotypic classification; (8) treat HFpEF patients now by treating their comorbidities; (9) understand the importance of heart rate in HFpEF- lower is not always better; and (10) do not forget to consider rare diseases ("zebras") as causes for HFpEF when evaluating and treating patients. Taken together, these 10 key lessons can help clinicians care for challenging patients with HFpEF while we eagerly await the results of ongoing HFpEF clinical trials and observational studies.

  11. Serum uric acid is associated with cardiac diastolic dysfunction among women with preserved ejection fraction.

    PubMed

    Nogi, Shinpei; Fujita, Shu-Ichi; Okamoto, Yusuke; Kizawa, Shun; Morita, Hideaki; Ito, Takahide; Sakane, Kazushi; Sohmiya, Koichi; Hoshiga, Masaaki; Ishizaka, Nobukazu

    2015-09-01

    Serum uric acid (SUA) is associated with the severity and prognosis of systolic heart failure. We investigated the potential association between SUA and cardiac diastolic dysfunction among total of 744 cardiac patients (202 women and 542 men) who had preserved left ventricular ejection fraction. Presence of diastolic dysfunction was assessed by echocardiographic data, plasma B-type natriuretic peptide concentration, and left ventricular hypertrophy. Univariate analysis showed that the prevalence of diastolic dysfunction increased with increasing SUA value in women, but not in men. When sex-nonspecific SUA quartiles were used, multivariate logistic regression analysis, among female patients who were not taking uric acid lowering medication, showed that the third (SUA, 5.7-6.4 mg) and the fourth (SUA, ≥6.5 mg/dl) SUA quartiles were associated with diastolic dysfunction with an odds ratio of 3.25 (P < 0.05) and 8.06 (P < 0.001), respectively, when compared with the first SUA quartile (≤4.7 mg/dl). When sex-specific SUA quartiles were used among these population, multivariate logistic regression analysis showed that the fourth SUA quartile (≥5.7 mg/dl) was associated with diastolic dysfunction with an odds ratio of 5.34 (P < 0.05) when compared with the first SUA quartile (≤4.1 mg/dl). By contrast, the relationship between SUA and diastolic dysfunction was not significant in men, irrespective of which of the sex-nonspecific or sex-specific SUA quartiles were used. These data indicated that among cardiac patients with preserved ejection fraction, SUA was significantly associated with diastolic dysfunction in women but not in men.

  12. Systolic Strain Abnormalities to Predict Hospital Readmission in Patients With Heart Failure and Normal Ejection Fraction

    PubMed Central

    Borer, Steven M.; Kokkirala, Aravind; O'Sullivan, David M.; Silverman, David I.

    2011-01-01

    Background Despite intensive investigation, the pathogenesis of heart failure with normal ejection fraction (HFNEF) remains unclear. We hypothesized that subtle abnormalities of systolic function might play a role, and that abnormal systolic strain and strain rate would provide a marker for adverse outcomes. Methods Patients of new CHF and left ventricular ejection fraction > 50% were included. Exclusion criteria were recent myocardial infarction, severe valvular heart disease, severe left ventricular hypertrophy (septum >1.8 cm), or a technically insufficient echocardiogram. Average peak systolic strain and strain rate were measured using an off-line grey scale imaging technique. Systolic strain and strain rate for readmitted patients were compared with those who remained readmission-free. Results One hundred consecutive patients with a 1st admission for HFNEF from January 1, 2004 through December 31, 2007, inclusive, were analyzed. Fifty two patients were readmitted with a primary diagnosis of heart failure. Systolic strain and strain rates were reduced in both study groups compared to controls. However, systolic strain did not differ significantly between the two groups (-11.7% for those readmitted compared with -12.9% for those free from readmission, P = 0.198) and systolic strain rates also were similar (-1.05 s-1 versus -1.09 s-1, P = 0.545). E/e’ was significantly higher in readmitted patients compared with those who remained free from readmission (14.5 versus 11.0, P = 0.013). E/e’ (OR 1.189, 95% CI 1.026-1.378; P = 0.021) was found to be an independent predictor for HFNEF readmission. Conclusions Among patients with new onset HFNEF, SS and SR rates are reduced compared with patients free of HFNEF, but do not predict hospital readmission. Elevated E/e’ is a predictor of readmission in these patients.

  13. Computer-based assessment of left ventricular regional ejection fraction in patients after myocardial infarction

    NASA Astrophysics Data System (ADS)

    Teo, S.-K.; Su, Y.; Tan, R. S.; Zhong, L.

    2014-03-01

    After myocardial infarction (MI), the left ventricle (LV) undergoes progressive remodeling which adversely affects heart function and may lead to development of heart failure. There is an escalating need to accurately depict the LV remodeling process for disease surveillance and monitoring of therapeutic efficacy. Current practice of using ejection fraction to quantitate LV function is less than ideal as it obscures regional variation and anomaly. Therefore, we sought to (i) develop a quantitative method to assess LV regional ejection fraction (REF) using a 16-segment method, and (ii) evaluate the effectiveness of REF in discriminating 10 patients 1-3 months after MI and 9 normal control (sex- and agematched) based on cardiac magnetic resonance (CMR) imaging. Late gadolinium enhancement (LGE) CMR scans were also acquired for the MI patients to assess scar extent. We observed that the REF at the basal, mid-cavity and apical regions for the patient group is significantly lower as compared to the control group (P < 0.001 using a 2-tail student t-test). In addition, we correlated the patient REF over these regions with their corresponding LGE score in terms of 4 categories - High LGE, Low LGE, Border and Remote. We observed that the median REF decreases with increasing severity of infarction. The results suggest that REF could potentially be used as a discriminator for MI and employed to measure myocardium homogeneity with respect to degree of infarction. The computational performance per data sample took approximately 25 sec, which demonstrates its clinical potential as a real-time cardiac assessment tool.

  14. Follistatin like 1 Regulates Hypertrophy in Heart Failure with Preserved Ejection Fraction

    PubMed Central

    Wilson, Richard M.; Essick, Eric E.; Fowler, Conor T.; Nakamura, Kazuto; van den Hoff, Maurice; Ouchi, Noriyuki; Sam, Flora

    2016-01-01

    Objective We sought to determine whether Fstl1 plays a role in the regulation of cardiac hypertrophy in HFpEF. Background Heart failure (HF) with preserved ejection fraction (HFpEF), accounts for ~50% of all clinical presentations of HF and its prevalence is expected to increase. However, there are no evidence-based therapies for HFpEF; thus, HFpEF represents a major unmet need. Although hypertension is the single most important risk factor for HFpEF, with a prevalence of 60-89% from clinical trials and human HF registries, blood pressure therapy alone is insufficient to prevent and treat HFpEF. Follistatin like 1 (Fstl1), a divergent member of the follistatin family of extracellular glycoproteins, has previously been shown to be elevated in HF with reduced ejection fraction (HFrEF) and associated with increased left ventricular mass. Methods and Results In this study, blood levels of Fstl1 were increased in humans with HFpEF. This increase was also evident in mice with hypertension-induced HFpEF and adult rat ventricular myocytes stimulated with aldosterone. Treatment with recombinant Fstl1 abrogated aldosterone-induced cardiac myocyte hypertrophy, suggesting a role for Fstl1 in the regulation of hypertrophy in HFpEF. There was also a reduction in the E/A ratio, a measure of diastolic dysfunction. Furthermore, HFpEF induced in a mouse model that specifically ablates Fstl1 in cardiac myocytes (cFstl1-KO), showed exacerbation of HFpEF with worsened diastolic dysfunction. In addition, cFstl1-KO-HFpEF mice demonstrated more marked cardiac myocyte hypertrophy with increased molecular markers of anp and bnp expression. Conclusions These findings indicate that Fstl1exerts therapeutic effects by modulating cardiac hypertrophy in HFpEF. PMID:27430031

  15. Left-ventricular peak ejection rate, filling rate, and ejection fraction--frame rate requirements at rest and exercise: concise communication.

    PubMed

    Bacharach, S L; Green, M V; Borer, J S; Hyde, J E; Farkas, S P; Johnston, G S

    1979-03-01

    The effect of framing rate on the measurement of left-ventricular (LV) ejection fraction (EF), peak ejection rate (PER), and peak filling rate (PFR) was evaluated at rest and during exercise in 11 normal subjects and 21 patients who underwent gated equilibrium blood-pool imaging. Left-ventricular time-activity curves were obtained in each subject, at rest and during stress, at temporal resolutions of 10, 20, 30, 40, and 50 msec per frame. Ejection fraction, PER, and PFR were determined for each frame duration. By observing changes in the measured values of these quantities with framing rate we conclude that: a) for the measurement of EF, 50 msec per frame at rest and 40 msec per frame at exercise is sufficient; b) PER requires 40 msec per frame at rest and 20 msec per frame during exercise; and c) for the measurement of PFR, at least 40 msec per frame at rest and 20 msec per frame during exercise are needed. These results should hold for both first-pass and gated equilibrium studies.

  16. RECURRENT STROKE IN THE WARFARIN VERSUS ASPIRIN IN REDUCED EJECTION FRACTION (WARCEF) TRIAL

    PubMed Central

    Pullicino, Patrick M.; Qian, Min; Sacco, Ralph L.; Freudenberger, Ron; Graham, Susan; Teerlink, John R.; Mann, Douglas; Di Tullio, Marco R.; Ponikowski, Piotr; Lok, Dirk J.; Anker, Stefan D.; Lip, Gregory Y.H.; Estol, Conrado J.; Levin, Bruce; Mohr, J.P.; Thompson, John L. P.; Homma, Shunichi

    2014-01-01

    Background and Purpose WARCEF randomized 2305 patients in sinus rhythm with ejection fraction (EF) ≤35% to warfarin (INR 2.0–3.5) or aspirin 325 mg. Warfarin reduced the incident ischemic stroke (IIS) hazard rate by 48% over aspirin in a secondary analysis. The IIS rate in heart failure (HF) is too low to warrant routine anticoagulation but epidemiologic studies show that prior stroke increases the stroke risk in HF. We here explore IIS rates in WARCEF patients with and without baseline stroke to look for risk factors for IIS and determine if a subgroup with an IIS rate high enough to give a clinically relevant stroke risk reduction can be identified. Methods We compared potential stroke risk factors between patients with baseline stroke and those without using the exact conditional score test for Poisson variables. We looked for risk factors for IIS, by comparing IIS rates between different risk factors. For EF we tried cutoff points of 10%, 15% and 20%. 15% was used as it was the highest EF that was associated with a significant increase in IIS rate. IIS and EF strata were balanced as to warfarin/aspirin assignment by the stratified randomized design. A multiple Poisson regression examined the simultaneous effects of all risk factors on IIS rate. IIS rates per hundred patient years (/100PY) were calculated in patient groups with significant risk factors. Missing values were assigned the modal value. Results Twenty of 248 (8.1%) patients with baseline stroke and 64 of 2048 (3.1%) without had IIS. IIS rate in patients with baseline stroke (2.37/100PY) was greater than patients without (0.89/100PY)(rate ratio 2.68, p<0.001). Fourteen of 219 (6.4%) patients with ejection fraction (EF)<15% and 70 of 2079 (3.4%) with EF ≥15% had IIS. In the multiple regression analysis stroke at baseline (p<0.001) and EF<15% vs. ≥15% (p=.005) remained significant predictors of IIS. IIS rate was 2.04/100PY in patients with EF<15% and 0.95/100PY in patients with EF ≥15% (p=0

  17. An evidence-based review of recent advances in therapy for heart failure with reduced ejection fraction (HFrEF).

    PubMed

    Raj, Leah; Adhyaru, Bhavin

    2016-12-01

    An estimated 5.1 million Americans have chronic heart failure and this is expected to increase 25% by 2030. Heart failure is a clinical syndrome that evolves from either functional or structural changes to the ventricles that lead to filling or ejection abnormalities. Thus far, pharmacotherapy has been show to be beneficial in patients only with reduced ejection fraction; however, new therapies have been developed in hopes of reducing the burden of heart failure. In this review, we will discuss current pharmacotherapies recommended in American College of Cardiology/American Heart Association guidelines, the evidence behind these recommendations as well as new and emerging therapies that have been developed.

  18. Tensor Factorization for Precision Medicine in Heart Failure with Preserved Ejection Fraction.

    PubMed

    Luo, Yuan; Ahmad, Faraz S; Shah, Sanjiv J

    2017-01-23

    Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous clinical syndrome that may benefit from improved subtyping in order to better characterize its pathophysiology and to develop novel targeted therapies. The United States Precision Medicine Initiative comes amid the rapid growth in quantity and modality of clinical data for HFpEF patients ranging from deep phenotypic to trans-omic data. Tensor factorization, a form of machine learning, allows for the integration of multiple data modalities to derive clinically relevant HFpEF subtypes that may have significant differences in underlying pathophysiology and differential response to therapies. Tensor factorization also allows for better interpretability by supporting dimensionality reduction and identifying latent groups of data for meaningful summarization of both features and disease outcomes. In this narrative review, we analyze the modest literature on the application of tensor factorization to related biomedical fields including genotyping and phenotyping. Based on the cited work including work of our own, we suggest multiple tensor factorization formulations capable of integrating the deep phenotypic and trans-omic modalities of data for HFpEF, or accounting for interactions between genetic variants at different omic hierarchies. We encourage extensive experimental studies to tackle challenges in applying tensor factorization for precision medicine in HFpEF, including effectively incorporating existing medical knowledge, properly accounting for uncertainty, and efficiently enforcing sparsity for better interpretability.

  19. The aortic ejection fraction: A new technique for diagnosing aortic insufficiency

    SciTech Connect

    Kantor, J.C.; Siegel, M.E.; Colletti, P.; McKay, C.; Lee, K.; Halls, J.; Jacobs, L.; Yamauchi, D.; Rahimtoola, S.

    1984-01-01

    Pulsations of the ascending aorta during fluoroscopy in patients (pts) with aortic insufficiency (AI) have been described. The authors observed a similar phenomenon in pts undergoing scintiangiography who have documented AI. This paper describes a technique to validate and quantitate this observation. The authors studied 17 patients with AI documented by cardiac catheterization and 14 subjects of a demographically matched control group with no evidence of AI. First pass studies were acquired in the RAO 15/sup 0/ projection after a bolus of 20 mCi of Tc-99m pertechnetate. After framing, identical ROI's were placed over the proximal aorta during systole and diastole excluding activity of the pulmonary arteries and/or atria. An aortic ejection fraction (AEF) was determined. The calculated AEF data was correlated with the presence or absence of AI. The mean AEF from the group of 17 patients was 26.9 +- 7.0, while the mean for the non AI group was 12.0 +- 6.5. These are statistically different at the P < .01 level. An AEF of 18 optimally separates the 2 groups with a sensitivity, specificity, and accuracy of 88%, 86%, and 87% respectively. Preliminary data demonstrates a mean reduction in AEF of 14.6 units in the AI patients who, to date, have undergone aortic valve replacement. Initial data suggests that this technique, using the AEF, may be able to identify patients with AI without the task of isolating the right ventricle.

  20. Current Perspectives on Systemic Hypertension in Heart Failure with Preserved Ejection Fraction.

    PubMed

    Tam, Marty C; Lee, Ran; Cascino, Thomas M; Konerman, Matthew C; Hummel, Scott L

    2017-02-01

    Heart failure with preserved ejection fraction (HFpEF) is a prevalent but incompletely understood syndrome. Traditional models of HFpEF pathophysiology revolve around systemic HTN and other causes of increased left ventricular afterload leading to left ventricular hypertrophy (LVH) and diastolic dysfunction. However, emerging models attribute the development of HFpEF to systemic proinflammatory changes secondary to common comorbidities which include HTN. Alterations in passive ventricular stiffness, ventricular-arterial coupling, peripheral microvascular function, systolic reserve, and chronotropic response occur. As a result, HFpEF is heterogeneous in nature, making it difficult to prescribe uniform therapies to all patients. Nonetheless, treating systemic HTN remains a cornerstone of HFpEF management. Antihypertensive therapies have been linked to LVH regression and improvement in diastolic dysfunction. However, to date, no therapies have definitive mortality benefit in HFpEF. Non-pharmacologic management for HTN, including dietary modification, exercise, and treating sleep disordered breathing, may provide some morbidity benefit in the HFpEF population. Future research is need to identify effective treatments, perhaps in more specific subgroups, and focus may need to shift from reducing mortality to improving exercise capacity and symptoms. Tailoring antihypertensive therapies to specific phenotypes of HFpEF may be an important component of this strategy.

  1. Electrophysiologic testing guided risk stratification approach for sudden cardiac death beyond the left ventricular ejection fraction.

    PubMed

    Gatzoulis, Konstantinos A; Tsiachris, Dimitris; Arsenos, Petros; Tousoulis, Dimitris

    2016-01-26

    Sudden cardiac death threats ischaemic and dilated cardiomyopathy patients. Anti- arrhythmic protection may be provided to these patients with implanted cardiac defibrillators (ICD), after an efficient risk stratification approach. The proposed risk stratifier of an impaired left ventricular ejection fraction has limited sensitivity meaning that a significant number of victims will remain undetectable by this risk stratification approach because they have a preserved left ventricular systolic function. Current risk stratification strategies focus on combinations of non invasive methods like T wave alternans, late potentials, heart rate turbulence, deceleration capacity and others, with invasive methods like the electrophysiologic study. In the presence of an electrically impaired substrate with formed post myocardial infarction fibrotic zones, programmed ventricular stimulation provides important prognostic information for the selection of the patients expected to benefit from an ICD implantation, while due to its high negative predictive value, patients at low risk level may also be detected. Clustering evidence from different research groups and electrophysiologic labs support an electrophysiologic testing guided risk stratification approach for sudden cardiac death.

  2. Sacubitril/Valsartan: A Review in Chronic Heart Failure with Reduced Ejection Fraction.

    PubMed

    McCormack, Paul L

    2016-03-01

    Sacubitril/valsartan (Entresto™; LCZ696) is an orally administered supramolecular sodium salt complex of the neprilysin inhibitor prodrug sacubitril and the angiotensin receptor blocker (ARB) valsartan, which was recently approved in the US and the EU for the treatment of chronic heart failure (NYHA class II-IV) with reduced ejection fraction (HFrEF). In the large, randomized, double-blind, PARADIGM-HF trial, sacubitril/valsartan reduced the incidence of death from cardiovascular causes or first hospitalization for worsening heart failure (composite primary endpoint) significantly more than the angiotensin converting enzyme (ACE) inhibitor enalapril. Sacubitril/valsartan was also superior to enalapril in reducing death from any cause and in limiting the progression of heart failure. Sacubitril/valsartan was generally well tolerated, with no increase in life-threatening adverse events. Symptomatic hypotension was significantly more common with sacubitril/valsartan than with enalapril; the incidence of angio-oedema was low. Therefore, sacubitril/valsartan is a more effective replacement for an ACE inhibitor or an ARB in the treatment of HFrEF, and is likely to influence the basic approach to treatment.

  3. Role of preoperative radionuclide ejection fraction in direct abdominal aortic aneurysm repair

    SciTech Connect

    Kazmers, A.; Cerqueira, M.D.; Zierler, R.E.

    1988-08-01

    Preoperative radionuclide ventriculography was performed in 60 patients to assess whether such testing could define those at increased risk after direct abdominal aortic aneurysm (AAA) repair. None of the patients had prophylactic coronary artery reconstruction to reduce the risk of AAA repair despite angina in 27% and previous myocardial infarction (MI) in 42%. The mean ejection fraction (EF) was 52% +/- 15% (range 14% to 78%). Low EF (normal greater than 50%) was present in 40%, whereas ventricular wall motion abnormalities were present in 39% of patients. The overall perioperative (30-day) mortality rate was 5%. MI occurred in 7% within 30 postoperative days; none was fatal. Life-table analysis revealed that overall survival after AAA repair was significantly lower in patients with an EF of 50% or less (p less than 0.025, Mantel-Cox) during a follow-up of 20.1 +/- 11.9 months. Overall survival differences were even more striking for those with an EF of 35% or less (p = 0.003, Mantel-Cox). There was a marked difference in the cumulative mortality rate during follow-up, being 50% in those patients with an EF of 35% or less (n = 10) compared with 14% in those with an EF greater than 35% (n = 50, p = 0.036, Fisher exact test). There was no statistical difference in the incidence of perioperative MI or perioperative death for those with an EF of 35% or less vs EF greater than 35%. 50 references.

  4. The Nitrate-nitrite-NO pathway and its implications for Heart Failure and Preserved Ejection Fraction

    PubMed Central

    Chirinos, Julio A.; Zamani, Payman

    2016-01-01

    The pathogenesis of exercise intolerance in patients with heart failure and preserved ejection fraction (HFpEF) is likely multifactorial. In addition to cardiac abnormalities (diastolic dysfunction, abnormal contractile reserve, chronotropic incompetence), several peripheral abnormalities are likely to be involved. These include abnormal pulsatile hemodynamics, abnormal arterial vasodilatory responses to exercise, and abnormal peripheral O2 delivery, extraction and utilization. The nitrate-nitrite-NO pathway is emerging as a potential target to modify key physiologic abnormalities, including late systolic LV load from arterial wave reflections (which has deleterious short- and long-term consequences for the LV), arterial vasodilatory reserve, muscle O2 delivery, and skeletal muscle mitochondrial function. In a recently completed randomized trial, the administration of a single dose of exogenous inorganic nitrate has been shown exert various salutary arterial hemodynamic effects, ultimately leading to enhanced aerobic capacity in patients with HFpEF. These effects have the potential for both immediate improvements in exercise tolerance and for long-term “disease-modifying” effects. In this review, we provide an overview of key mechanistic contributors to exercise intolerance in HFpEF, and of the potential therapeutic role of drugs that target the nitrate-nitrite-NO pathway. PMID:26792295

  5. Noncardiac Comorbidities in Heart Failure With Reduced Versus Preserved Ejection Fraction

    PubMed Central

    Mentz, Robert J.; Kelly, Jacob P.; von Lueder, Thomas G.; Voors, Adriaan A.; Lam, Carolyn S. P.; Cowie, Martin R.; Kjeldsen, Keld; Jankowska, Ewa A.; Atar, Dan; Butler, Javed; Fiuzat, Mona; Zannad, Faiez; Pitt, Bertram; O’Connor, Christopher M.

    2014-01-01

    Heart failure patients are classified by ejection fraction (EF) into distinct groups: heart failure with preserved EF (HFpEF) or heart failure with reduced EF (HFrEF). Although patients with heart failure commonly have multiple comorbidities that complicate management and may adversely affect outcomes, their role in the HFpEF and HFrEF groups is not well-characterized. This review summarizes the role of noncardiac comorbidities in patients with HFpEF versus HFrEF, emphasizing prevalence, underlying pathophysiologic mechanisms, and outcomes. Pulmonary disease, diabetes mellitus, anemia, and obesity tend to be more prevalent in HFpEF patients, but renal disease and sleep-disordered breathing burdens are similar. These comorbidities similarly increase morbidity and mortality risk in HFpEF and HFrEF patients. Common pathophysiologic mechanisms include systemic and endomyocardial inflammation with fibrosis. We also discuss implications for clinical care and future HF clinical trial design. The basis for this review was discussions between scientists, clinical trialists, and regulatory representatives at the 10th Global CardioVascular Clinical Trialists Forum. PMID:25456761

  6. Prognostic value of right ventricular ejection fraction in pulmonary arterial hypertension.

    PubMed

    Courand, Pierre-Yves; Pina Jomir, Géraldine; Khouatra, Chahéra; Scheiber, Christian; Turquier, Ségolène; Glérant, Jean-Charles; Mastroianni, Bénédicte; Gentil, Béatrice; Blanchet-Legens, Anne-Sophie; Dib, Alfred; Derumeaux, Geneviève; Humbert, Marc; Mornex, Jean-François; Cordier, Jean-François; Cottin, Vincent

    2015-01-01

    Right ventricle ejection fraction (RVEF) evaluated with magnetic resonance imaging is a strong determinant of patient outcomes in pulmonary arterial hypertension. We evaluated the prognostic value of RVEF assessed with conventional planar equilibrium radionuclide angiography at baseline and change 3-6 months after initiating pulmonary arterial hypertension-specific therapy. In a prospective cohort of newly diagnosed patients with idiopathic, heritable or anorexigen-associated pulmonary arterial hypertension, RVEF was measured at baseline (n=100) and 3-6 months after initiation of therapy (n=78). After a median follow-up of 4.1 years, 41 deaths occurred, including 35 from cardiovascular causes. Patients with a (median) baseline RVEF >25% had better survival than those with a RVEF <25% using Kaplan-Meier analysis (p=0.010). RVEF at baseline was an independent predictor of all-cause and cardiovascular mortality in adjusted Cox regression model (p=0.002 and p=0.007, respectively; HR 0.93 for both). Patients with stable or increased RVEF at 3-6 months had a trend for improved all-cause survival (HR 2.43, p=0.086) and had less cardiovascular mortality (HR 3.25, p=0.034) than those in whom RVEF decreased despite therapy. RVEF assessed with conventional planar equilibrium radionuclide angiography at baseline and change in RVEF 3-6 months after therapy initiation independently predict outcomes in patients with pulmonary arterial hypertension.

  7. Extraction of left ventricular ejection fraction information from various types of clinical reports.

    PubMed

    Kim, Youngjun; Garvin, Jennifer H; Goldstein, Mary K; Hwang, Tammy S; Redd, Andrew; Bolton, Dan; Heidenreich, Paul A; Meystre, Stéphane M

    2017-03-01

    Efforts to improve the treatment of congestive heart failure, a common and serious medical condition, include the use of quality measures to assess guideline-concordant care. The goal of this study is to identify left ventricular ejection fraction (LVEF) information from various types of clinical notes, and to then use this information for heart failure quality measurement. We analyzed the annotation differences between a new corpus of clinical notes from the Echocardiography, Radiology, and Text Integrated Utility package and other corpora annotated for natural language processing (NLP) research in the Department of Veterans Affairs. These reports contain varying degrees of structure. To examine whether existing LVEF extraction modules we developed in prior research improve the accuracy of LVEF information extraction from the new corpus, we created two sequence-tagging NLP modules trained with a new data set, with or without predictions from the existing LVEF extraction modules. We also conducted a set of experiments to examine the impact of training data size on information extraction accuracy. We found that less training data is needed when reports are highly structured, and that combining predictions from existing LVEF extraction modules improves information extraction when reports have less structured formats and a rich set of vocabulary.

  8. Myocardial Hypertrophy and Its Role in Heart Failure with Preserved Ejection Fraction

    PubMed Central

    Heinzel, Frank R.; Hohendanner, Felix; Jin, Ge; Sedej, Simon; Edelmann, Frank

    2015-01-01

    Left ventricular hypertrophy (LVH) is the most common myocardial structural abnormality associated with heart failure with preserved ejection fraction (HFpEF). LVH is driven by neurohumoral activation, increased mechanical load and cytokines associated with arterial hypertension, chronic kidney disease, diabetes and other co-morbidities. Here we discuss the experimental and clinical evidence that links LVH to diastolic dysfunction and qualifies LVH as one diagnostic marker for HFpEF. Mechanisms leading to diastolic dysfunction in LVH are incompletely understood but may include extracellular matrix changes, vascular dysfunction as well as altered cardiomyocyte mechano-elastical properties. Beating cardiomyocytes from HFpEF patients have not yet been studied, but we and others have shown increased Ca2+ turnover and impaired relaxation in cardiomyocytes from hypertrophied hearts. Structural myocardial remodeling can lead to heterogeneity in regional myocardial contractile function, which contributes to diastolic dysfunction in HFpEF. In the clinical setting of patients with compound co-morbidities, diastolic dysfunction may occur independently of LVH. This may be one explanation why current approaches to reduce LVH have not been effective to improve symptoms and prognosis in HFpEF. Exercise training on the other hand, in clinical trials improved exercise tolerance and diastolic function but did not reduce LVH. Thus, current clinical evidence does not support regression of LVH as a surrogate marker for (short-term) improvement of HFpEF. PMID:26183480

  9. Sarcopenic Obesity and the Pathogenesis of Exercise Intolerance in Heart Failure With Preserved Ejection Fraction

    PubMed Central

    Upadhya, Bharathi; Haykowsky, Mark J.; Eggebeen, Joel; Kitzman, Dalane W.

    2016-01-01

    Heart failure with preserved ejection fraction (HFpEF) is the most common form of heart failure (HF) in older adults. The primary chronic symptom in patients with HFpEF, even when well compensated, is severe exercise intolerance. Cardiac and peripheral functions contribute equally to exercise intolerance in HFpEF, though the latter has been the focus of fewer studies. Of note, multiple studies with exercise training have shown that exercise intolerance can improve significantly in the absence of improvements in exercise cardiac output, indicating a role of peripheral, non-cardiac adaptations. In addition, clinical drug trials performed to date in HFpEF, all of which have focused on influencing cardiovascular function, have not been positive on primary clinical outcomes and most have not improved exercise capacity. Mounting evidence indicates that sarcopenic obesity, characterized by the coexistence of excess fat mass and decreased muscle mass, could contribute to the pathophysiology of exercise intolerance in older HFpEF patients and may provide avenues for novel treatments. PMID:25750186

  10. Myocardial hypertrophy and its role in heart failure with preserved ejection fraction.

    PubMed

    Heinzel, Frank R; Hohendanner, Felix; Jin, Ge; Sedej, Simon; Edelmann, Frank

    2015-11-15

    Left ventricular hypertrophy (LVH) is the most common myocardial structural abnormality associated with heart failure with preserved ejection fraction (HFpEF). LVH is driven by neurohumoral activation, increased mechanical load, and cytokines associated with arterial hypertension, chronic kidney disease, diabetes, and other comorbidities. Here we discuss the experimental and clinical evidence that links LVH to diastolic dysfunction and qualifies LVH as one diagnostic marker for HFpEF. Mechanisms leading to diastolic dysfunction in LVH are incompletely understood, but may include extracellular matrix changes, vascular dysfunction, as well as altered cardiomyocyte mechano-elastical properties. Beating cardiomyocytes from HFpEF patients have not yet been studied, but we and others have shown increased Ca(2+) turnover and impaired relaxation in cardiomyocytes from hypertrophied hearts. Structural myocardial remodeling can lead to heterogeneity in regional myocardial contractile function, which contributes to diastolic dysfunction in HFpEF. In the clinical setting of patients with compound comorbidities, diastolic dysfunction may occur independently of LVH. This may be one explanation why current approaches to reduce LVH have not been effective to improve symptoms and prognosis in HFpEF. Exercise training, on the other hand, in clinical trials improved exercise tolerance and diastolic function, but did not reduce LVH. Thus current clinical evidence does not support regression of LVH as a surrogate marker for (short-term) improvement of HFpEF.

  11. Two-Dimensional Speckle Tracking Echocardiography Predict Left Ventricular Remodeling after Acute Myocardial Infarction in Patients with Preserved Ejection Fraction

    PubMed Central

    Hsiao, Ju-Feng; Chung, Chang-Min; Chu, Chi-Ming; Lin, Yu-Shen; Pan, Kuo-Li; Chang, Shih-Tai

    2016-01-01

    Objectives Left ventricular remodeling after acute myocardial infarction increases cardiovascular events and mortality. But few study was done in patients with preserved ejection fraction (EF > 40%). We investigate whether the strain and strain rate by 2D speckle tracking echocardiography could predict left ventricular remodeling after acute myocardial infarction in this cohort. Methods The 83 patients (average age 60.7 ± 12.3 y, 75 [90.4%] male) with new-onset acute myocardial infarction receiving echocardiography immediately, and 6 months after admission were grouped by the presence or absence of left ventricular remodeling. Strain and strain rate including longitudinal, circumferential, and radial direction were calculated. The average of strain and strain rate of which segmental longitudinal strains > – 15% were defined as the injury longitudinal strain (InjLS). Results Left ventricular remodeling occurred in 24 of 83 patients (28.9%). In univariate logistic regression analyses, gender, peak CK-MB, log BNP, use of statin before discharge, wall motion score index, and InjLS were significantly associated with left ventricular remodeling (p < 0.05). In multivariate analysis using the forward stepwise method, gender, CK-MB, and InjLS were independent predictors. The hazard ratio for InjLS was 1.48 (p = 0.04). Receiver operating characteristic curve (ROC) analyses showed the area under the curve (AUC) of InjLS was largest (AUC = 0.75, cut-off value = –11.7%, sensitivity = 81%, specificity = 71%, p < 0.01). In ST-segment elevation myocardial infarction subgroup, InjLS was the only predictor according to ROC analysis (AUC = 0.79, p < 0.01, cut-off value = –11.4%, sensitivity = 88%, specificity = 77%) and multivariate logistic regression analysis (hazard ratio = 1.88, 95% CI: 1.22–2.88, p < 0.01). Conclusions InjLS was an excellent predictor for left ventricular remodeling after acute myocardial infarction in patient with preserved ejection fraction. PMID

  12. Development of Left Ventricular Diastolic Dysfunction with Preservation of Ejection Fraction during Progression of Infant Right Ventricular Hypertrophy

    PubMed Central

    Kitahori, Kazuo; He, Huamei; Kawata, Mitsuhiro; Cowan, Douglas B.; Friehs, Ingeborg; del Nido, Pedro J.; McGowan, Francis X.

    2011-01-01

    Background Progressive left ventricular (LV) dysfunction can be a major late complication in patients with chronic right ventricular (RV) pressure overload (e.g., tetralogy of Fallot). We therefore examined LV function (serial echocardiography and ex vivo Langendorff) and histology in a model of infant pressure-load RV hypertrophy (RVH). Methods and Results Ten-day-old rabbits (N=6 per time point, total = 48) that underwent pulmonary artery banding (PAB) were sacrificed at 2–8 weeks after PAB, and comparisons were made with age-matched sham controls. LV performance (myocardial performance index, MPI) decreased during the progression of RVH although the LV ejection fraction (EF) was maintained. In addition, RVH caused significant septal displacement, reduced septal contractility, and decreased LV end-systolic (LVDs) and diastolic (LVDd) dimensions, resulting in LV diastolic dysfunction with the appearance of preserved EF. Significant septal and LV free wall apoptosis (myocyte-specific TUNEL and activated caspase-3), fibrosis (Masson’s trichrome stain), and reduced capillary density (CD31 immunostaining) occurred in the PAB group after 6–8 wks (all p<0.05). Conclusion This is the first study showing that pressure overload of the RV resulting in RVH causes LV diastolic dysfunction while preserving EF through mechanical and molecular effects upon the septum and LV myocardium. In particular, the development of RVH is associated with septal and LV apoptosis and reduced LV capillary density. PMID:19919985

  13. Role of biomarkers in cardiac structure phenotyping in heart failure with preserved ejection fraction: critical appraisal and practical use.

    PubMed

    D'Elia, Emilia; Vaduganathan, Muthiah; Gori, Mauro; Gavazzi, Antonello; Butler, Javed; Senni, Michele

    2015-12-01

    Heart failure (HF) with preserved ejection fraction (HFpEF) is a heterogeneous clinical syndrome characterized by cardiovascular, metabolic, and pro-inflammatory diseases associated with advanced age and extracardiac comorbidities. All of these conditions finally lead to impairment of myocardial structure and function. The large phenotypic heterogeneity of HFpEF from pathophysiological underpinnings presents a major hurdle to HFpEF therapy. The new therapeutic approach in HFpEF should be targeted to each HF phenotype, instead of the 'one-size-fits-all' approach, which has not been successful in clinical trials. Unless the structural and biological determinants of the failing heart are deeply understood, it will be impossible to appropriately differentiate HFpEF patients, identify subtle myocardial abnormalities, and finally reverse abnormal cardiac function. Based on evidence from endomyocardial biopsies, some of the specific cardiac structural phenotypes to be targeted in HFpEF may be represented by myocyte hypertrophy, interstitial fibrosis, myocardial inflammation associated with oxidative stress, and coronary disease. Once the diagnosis of HFpEF has been established, a potential approach could be to use a panel of biomarkers to identify the main cardiac structural HFpEF phenotypes, guiding towards more appropriate therapeutic strategies. Accordingly, the purpose of this review is to investigate the potential role of biomarkers in identifying different cardiac structural HFpEF phenotypes and to discuss the merits of a biomarker-guided strategy in HFpEF.

  14. Renin-Angiotensin Activation and Oxidative Stress in Early Heart Failure with Preserved Ejection Fraction

    PubMed Central

    Negi, Smita I.; Jeong, Euy-Myoung; Shukrullah, Irfan; Veleder, Emir; Jones, Dean P.; Fan, Tai-Hwang M.; Varadarajan, Sudhahar; Danilov, Sergei M.; Fukai, Tohru; Dudley, Samuel C.

    2015-01-01

    Animal models have suggested a role of renin-angiotensin system (RAS) activation and subsequent cardiac oxidation in heart failure with preserved ejection fraction (HFpEF). Nevertheless, RAS blockade has failed to show efficacy in treatment of HFpEF. We evaluated the role of RAS activation and subsequent systemic oxidation in HFpEF. Oxidative stress markers were compared in 50 subjects with and without early HFpEF. Derivatives of reactive oxidative metabolites (DROMs), F2-isoprostanes (IsoPs), and ratios of oxidized to reduced glutathione (Eh GSH) and cysteine (Eh CyS) were measured. Angiotensin converting enzyme (ACE) levels and activity were measured. On univariate analysis, HFpEF was associated with male sex (p = 0.04), higher body mass index (BMI) (p = 0.003), less oxidized Eh CyS (p = 0.001), lower DROMs (p = 0.02), and lower IsoP (p = 0.03). Higher BMI (OR: 1.3; 95% CI: 1.1–1.6) and less oxidized Eh CyS (OR: 1.2; 95% CI: 1.1–1.4) maintained associations with HFpEF on multivariate analysis. Though ACE levels were higher in early HFpEF (OR: 1.09; 95% CI: 1.01–1.05), ACE activity was similar to that in controls. HFpEF is not associated with significant systemic RAS activation or oxidative stress. This may explain the failure of RAS inhibitors to alter outcomes in HFpEF. PMID:26504834

  15. Reporting trends of randomised controlled trials in heart failure with preserved ejection fraction: a systematic review

    PubMed Central

    Zheng, Sean L; Chan, Fiona T; Maclean, Edd; Jayakumar, Shruti; Nabeebaccus, Adam A

    2016-01-01

    Background Heart failure with preserved ejection fraction (HFpEF) causes significant cardiovascular morbidity and mortality. Current consensus guidelines reflect the neutral results from randomised controlled trials (RCTs). Adequate trial reporting is a fundamental requirement before concluding on RCT intervention efficacy and is necessary for accurate meta-analysis and to provide insight into future trial design. The Consolidated Standards of Reporting Trials (CONSORT) 2010 statement provides a framework for complete trial reporting. Reporting quality of HFpEF RCTs has not been previously assessed, and this represents an important validation of reporting qualities to date. Objectives The aim was to systematically identify RCTs investigating the efficacy of pharmacological therapies in HFpEF and to assess the quality of reporting using the CONSORT 2010 statement. Methods MEDLINE, EMBASE and CENTRAL databases were searched from January 1996 to November 2015, with RCTs assessing pharmacological therapies on clinical outcomes in HFpEF patients included. The quality of reporting was assessed against the CONSORT 2010 checklist. Results A total of 33 RCTs were included. The mean CONSORT score was 55.4% (SD 17.2%). The CONSORT score was strongly correlated with journal impact factor (r=0.53, p=0.003) and publication year (r=0.50, p=0.003). Articles published after the introduction of CONSORT 2010 statement had a significantly higher mean score compared with those published before (64% vs 50%, p=0.02). Conclusions Although the CONSORT score has increased with time, a significant proportion of HFpEF RCTs showed inadequate reporting standards. The level of adherence to CONSORT criteria could have an impact on the validity of trials and hence the interpretation of intervention efficacy. We recommend improving compliance with the CONSORT statement for future RCTs. PMID:27547434

  16. Left ventricular ejection fraction response during exercise in asymptomatic systemic hypertension

    SciTech Connect

    Miller, D.D.; Ruddy, T.D.; Zusman, R.M.; Okada, R.D.; Strauss, H.W.; Kanarek, D.J.; Christensen, D.; Federman, E.B.; Boucher, C.A.

    1987-02-15

    To study the effect of mild-to-moderate elevations in diastolic blood pressure (BP) on systolic left ventricular (LV) function, 28 hypertensive patients and 20 normal subjects underwent upright exercise first-pass radionuclide angiography. All were asymptomatic, had normal rest and exercise electrocardiographic findings and no evidence of LV hypertrophy or coronary artery disease. LV function at rest was similar in the 2 groups, but with exercise hypertensive patients had a greater end-systolic volume (69 +/- 19 vs 51 +/- 19 ml, p less than 0.002) and lower ejection fraction (EF) (0.59 +/- 0.09 vs 0.72 +/- 0.07, p less than 0.0001), stroke volume (101 +/- 28 vs 130 +/- 36 ml, p less than 0.005) and peak oxygen uptake (23 +/- 7 vs 33 +/- 9 ml/kl/min, p less than 0.05). Hypertensive patients were separated into 3 groups: group 1-12 patients with an increase in EF with exercise greater than or equal to 0.05; group 2-7 patients with a change in EF with exercise less than 0.05; and group 3-9 patients with a decrease in EF with exercise greater than or equal to 0.05. Group 3 hypertensive patients were older, had a higher heart rate at rest and lower peak oxygen uptake. Rest LV function was similar in the 3 hypertensive subgroups, but exercise end-systolic volumes were higher in groups 2 and 3. Exercise thallium-201 images was normal in all but 1 of 14 hypertensive group 2 or 3 patients.

  17. Magnetic resonance imaging--cardiac ejection fraction measurements. Phantom study comparing four different methods.

    PubMed

    Debatin, J F; Nadel, S N; Sostman, H D; Spritzer, C E; Evans, A J; Grist, T M

    1992-03-01

    The accuracy of cardiac ejection fraction (EF) measurements with thin, contiguous cine-magnetic resonance imaging (MR) sections is well established. Still, faster imaging and measurement techniques would be desirable. The authors evaluated the accuracy of four different MR EF measurements methods in a biventricular, anthropomorphic, foam-latex rubber phantom which was connected via noncompliant fluid-filled tubing to a pulsatile flow pump. Nine contiguous 10 mm cine-MR sections (TR/TE, 25/13; flip angle, 45 degrees) were obtained through the heart in long and short cardiac axes at 16 frames per cardiac cycle at a pump rate of 60 beats/minute. EF measurements were based on either the multi-slice summation technique (nine contiguous 10-mm sections versus four 10-mm sections spaced 10 mm apart) or the area-length method (single largest long section versus combination of largest long- and short-axis section). Three replications were performed for each of the tested EFs (40.8%, 29.4%, and 13.4%), which were compared with actual EFs. EF measurements based on contiguous 1-cm sections correlated best with the actual EFs. Average relative errors ranged from 3.2% to 6.0%. EF measurements based on every other section were less accurate; average relative errors were between 5.2% and 10.2%. Single and biplane area-length algorithm EF measurements were significantly less accurate; average relative errors were as high as 59%. EF measurements based on multi-slice summation are more accurate than those based on the area-length algorithm. Contiguous 1-cm section acquisitions are most accurate and most time consuming. With slight decrease of accuracy, acquisition and processing times can be halved by skipping every other slice.

  18. Enhancing ejection fraction measurement through 4D respiratory motion compensation in cardiac PET imaging.

    PubMed

    Tang, Jing; Wang, Xinhui; Gao, Xiangzhen; Segars, Paul; Lodge, Martin; Rahmim, Arman

    2017-03-02

    ECG gated cardiac PET imaging measures functional parameters such as left ventricle (LV) ejection fraction (EF), providing diagnostic and prognostic information for management of patients with coronary artery disease (CAD). Respiratory motion degrades spatial resolution and affects the accuracy in measuring the LV volumes for EF calculation. The goal of this study is to systematically investigate the effect of respiratory motion correction on the estimation of end-diastolic volume (EDV), end-systolic volume (ESV), and EF, especially on the separation of normal and abnormal EFs. We developed a respiratory motion incorporated 4D PET image reconstruction technique which uses all gated-frame data to acquire a motion-suppressed image. Using the standard XCAT phantom and two individual-specific volunteer XCAT phantoms, we simulated dual-gated myocardial perfusion imaging data for normally and abnormally beating hearts. With and without respiratory motion correction, we measured the EDV, ESV, and EF from the cardiac gated reconstructed images. For all the phantoms, the estimated volumes increased and the biases significantly reduced with motion correction compared with those without. Furthermore, the improvement of ESV measurement in the abnormally beating heart led to better separation of normal and abnormal EFs. The simulation study demonstrated the significant effect of respiratory motion correction on cardiac imaging data with motion amplitude as small as 0.7 cm. The larger the motion amplitude the more improvement respiratory motion correction brought about on the measurement of EF. Using data-driven respiratory gating, we also demonstrated the effect of respiratory motion correction on estimation of the above functional parameters from list mode patient data. Respiratory motion correction is shown to improve the accuracy of EF measurement in clinical cardiac PET imaging.

  19. Impact of Ejection Fraction and Aortic Valve Gradient on Outcomes of Transcatheter Aortic Valve Replacement

    PubMed Central

    Baron, Suzanne J.; Arnold, Suzanne V.; Herrmann, Howard C.; Holmes, David; Szeto, Wilson Y.; Allen, Keith B.; Chhatriwalla, Adnan K.; Vemulapali, Sreekaanth; O’Brien, Sean; Dai, Dadi; Cohen, David J.

    2017-01-01

    Background In patients with aortic stenosis undergoing transcatheter aortic valve replacement (TAVR), prior studies have suggested that reduced left ventricular ejection fraction (LVEF) and low aortic valve gradient (AVG) are associated with worse long-term outcomes. Since these conditions commonly coexist, the extent to which they are independently associated with outcomes after TAVR is unknown. Objectives To evaluate the impact of LVEF and AVG on clinical outcomes after TAVR and to determine whether the effect of AVG on outcomes is modified by LVEF. Methods Using data from 11,292 patients who underwent TAVR as part of the TVT Registry, we examined rates of 1-year mortality and recurrent heart failure in patients with varying levels of LV dysfunction (LVEF < 30% vs. 30–50% vs. > 50%) and AVG (< 40mmHg vs. ≥ 40mmHg). Multivariable models were used to estimate the independent effect of AVG and LVEF on outcomes. Results Over the first year of follow-up after TAVR, patients with LV dysfunction and low AVG had higher rates of death and recurrent heart failure. After adjustment for other clinical factors, only low AVG was associated with higher mortality (HR 1.21, 95% CI 1.11–1.32; p < 0.001) and higher rates of heart failure (HR 1.52; 95% CI 1.36–1.69; p < 0.001), whereas the effect of LVEF was no longer significant. There was no evidence of effect modification between AVG and LVEF with respect to either endpoint. Conclusion In this large series of real world patients undergoing TAVR, low AVG, but not LV dysfunction, was associated with higher rates of mortality and recurrent heart failure. Although these findings suggest that AVG should be considered when evaluating the risks and benefits of TAVR for individual patients, neither severe LV dysfunction nor low AVG alone or in combination provide sufficient prognostic discrimination to preclude treatment with TAVR. PMID:27199058

  20. Phenotype-Specific Treatment of Heart Failure With Preserved Ejection Fraction: A Multiorgan Roadmap.

    PubMed

    Shah, Sanjiv J; Kitzman, Dalane W; Borlaug, Barry A; van Heerebeek, Loek; Zile, Michael R; Kass, David A; Paulus, Walter J

    2016-07-05

    Heart failure (HF) with preserved ejection fraction (EF; HFpEF) accounts for 50% of HF cases, and its prevalence relative to HF with reduced EF continues to rise. In contrast to HF with reduced EF, large trials testing neurohumoral inhibition in HFpEF failed to reach a positive outcome. This failure was recently attributed to distinct systemic and myocardial signaling in HFpEF and to diversity of HFpEF phenotypes. In this review, an HFpEF treatment strategy is proposed that addresses HFpEF-specific signaling and phenotypic diversity. In HFpEF, extracardiac comorbidities such as metabolic risk, arterial hypertension, and renal insufficiency drive left ventricular remodeling and dysfunction through systemic inflammation and coronary microvascular endothelial dysfunction. The latter affects left ventricular diastolic dysfunction through macrophage infiltration, resulting in interstitial fibrosis, and through altered paracrine signaling to cardiomyocytes, which become hypertrophied and stiff because of low nitric oxide and cyclic guanosine monophosphate. Systemic inflammation also affects other organs such as lungs, skeletal muscle, and kidneys, leading, respectively, to pulmonary hypertension, muscle weakness, and sodium retention. Individual steps of these signaling cascades can be targeted by specific interventions: metabolic risk by caloric restriction, systemic inflammation by statins, pulmonary hypertension by phosphodiesterase 5 inhibitors, muscle weakness by exercise training, sodium retention by diuretics and monitoring devices, myocardial nitric oxide bioavailability by inorganic nitrate-nitrite, myocardial cyclic guanosine monophosphate content by neprilysin or phosphodiesterase 9 inhibition, and myocardial fibrosis by spironolactone. Because of phenotypic diversity in HFpEF, personalized therapeutic strategies are proposed, which are configured in a matrix with HFpEF presentations in the abscissa and HFpEF predispositions in the ordinate.

  1. Mineralocorticoid receptor antagonists in heart failure with preserved ejection fraction (HFpEF).

    PubMed

    Capuano, Annalisa; Scavone, Cristina; Vitale, Cristiana; Sportiello, Liberata; Rossi, Francesco; Rosano, Giuseppe M C; Coats, Andrew J Stewart

    2015-12-01

    The role of spironolactone and eplerenone in patients with Heart Failure with preserved Ejection Fraction (HFpEF) is not well defined. Since a growing medical literature has suggested that mineralocorticoid receptor antagonists may be beneficial for patients with HFpEF, this review gives an in-depth update on the role of spironolactone and eplerenone and their implications for therapy in the setting of HFpEF. Eleven clinical studies, including seven randomized trials, were reviewed. Two randomized controlled trials evaluated the effect of eplerenone on different end-points, including 6 minute walk distance (6 MWD), cardiovascular mortality, non-fatal reinfarction, hospitalization for unstable angina and congestive heart failure. Eplerenone did not affect either 6 MWD or event-free survival rates in the overall study population in these two reports. The effects of spironolactone on similar composite endpoints were evaluated in 7 studies in patients with HFpEF. Compared to placebo, hospitalization for heart failure was significantly lower in the spironolactone group and spironolactone was also shown to improve diastolic function and induced beneficial remodeling through a reduction in myocardial fibrosis. The safety profile of spironolactone and eplerenone has been assessed in two recent studies. Data showed that eplerenone and spironolactone are both associated with the occurrence of gynecomastia, mastodynia, and abnormal vaginal bleeding and in addition, they can increase natriuresis and cause renal retention of potassium; furthermore, eplerenone may cause hyperkalemia and promote the onset of metabolic acidosis or hyponatremia. In conclusion although the mineralocorticoid receptor antagonists eplerenone and spironolactone improve clinical outcomes in patients with HFrEF, additional data will be necessary to better define their risk-benefit profile, especially for eplerenone, in the treatment of HFpEF.

  2. Left ventricular volume regulation in heart failure with preserved ejection fraction

    PubMed Central

    Kerkhof, Peter L M; Yasha Kresh, J; Li, John K-J; Heyndrickx, Guy R

    2013-01-01

    Ejection Fraction (EF) has attained the recognition as indicator of global ventricular performance. Remarkably, precise historical origins promoting the apparent importance of EF are scant. During early utilization EF has been declared a gold standard for the evaluation of the heart as a pump. In contrast, during the last two decades, clinicians have developed a measure of doubt in the universal applicability of EF. This reluctance lead to the introduction of a new and prevalent syndrome in which heart failure (HF) is diagnosed as having a preserved EF (pEF). We examine the existing criticism regarding EF, and describe a novel avenue to characterize ventricular function within the unifying framework of cardiac input–output volume regulation. This approach relates end-systolic volume (ESV) to end-diastolic volume (EDV), and derives for a subgroup matching pEF criteria a distinct pattern in the ESV–EDV domain. In patients with pEF (n = 34), a clear difference (P < 0.0004) in the slope of the regression line for ESV versus EDV was demonstrated compared to control patients with EF < 50% (n = 29). These findings are confirmed by analysis of data presented in two independent publications. The volume regulation approach proposed employs primary end-point determinants (such as ESV and EDV) rather than derived quantities (e.g., the ratio EF or its differential parameter, that is, stroke volume) and confirms a distinct advantage over the classical Starling curve. Application of the ESV-EDV-construct provides the basis and clarifies why some patients present as HFpEF, while others have reduced EF. PMID:24303121

  3. Influence of different background and left-ventricular assignments on the ejection fraction in equilibrium radionuclide angiography.

    PubMed

    Slutsky, R; Pfisterer, M; Verba, J; Battler, A; Ashburn, W

    1980-06-01

    Seventy-six patients were studied within one week of contrast ventriculography to assess the influence of differing background assignments on ejection fractions derived from gated equilibrium radionuclide anigograms. "Fixed" and "variable" left-ventricular regions on interest and five different backgrounds were used. Inter- and intra-observer variability were determined, and 15 patients underwent a second study 2 weeks later. Variable left-ventricular regions of interest produced higher ejection fractions than fixed ones. A computer-assigned background or a ring drawn manually around the left ventricle correlated best with contrast ventriculography, giving greater serial and inter- and intra-observer variability. Automated background assignments reduced variability and increased reproducibility, though not always associated with the best correlation with contrast ventriculography. Thus a variety of left-ventricular and background regions of interest gives excellent reproducibility and accuracy.

  4. [New therapeutic era in heart failure with reduced ejection fraction: Which population of French patients is concerned?].

    PubMed

    Juillière, Y; Ferrières, J

    2016-09-01

    A new class of cardiovascular drugs, angiotensin receptor neprilysin inhibitors, has shown its efficacy in the PARADIGM-HF study in replacement of renin-angiotensin blockers in symptomatic heart failure patients with reduced ejection fraction, and already treated according to the recommendations. Recent French epidemiological data in the literature allow assessing the number of French patients who could be concerned by the new treatment in taking account the different parameters from the PARADIGM-HF study.

  5. Quantification of Left Ventricular Volumes, Mass and Ejection Fraction using Cine Displacement Encoding with Stimulated Echoes (DENSE) MRI

    PubMed Central

    Haggerty, Christopher M.; Kramer, Sage P.; Skrinjar, Oskar; Binkley, Cassi M.; Powell, David K.; Mattingly, Andrea C.; Epstein, Frederick H.; Fornwalt, Brandon K.

    2014-01-01

    Purpose To test the hypothesis that magnitude images from cine Displacement Encoding with Stimulated Echoes (DENSE) MRI can accurately quantify left ventricular (LV) volumes, mass, and ejection fraction. Materials and Methods Thirteen mice (C57BL/6J) were imaged using a 7T ClinScan MRI. A short-axis stack of cine T2-weighted black blood (BB) images was acquired for calculation of left ventricular volumes, mass, and ejection fraction (EF) using the gold standard sum-of-slices methodology. DENSE images were acquired during the same imaging session in three short-axis (basal, mid, apical) and two long-axis orientations. A custom surface fitting algorithm was applied to epicardial and endocardial borders from the DENSE magnitude images to calculate volumes, mass, and EF. Agreement between the DENSE-derived measures and BB-derived measures was assessed via coefficient of variation (CoV). Results 3D surface reconstruction was completed on the order of seconds from segmented images, and required fewer slices to be segmented. Volumes, mass, and EF from DENSE-derived surfaces matched well with BB data (CoVs ≤11%). Conclusion LV mass, volumes, and ejection fraction in mice can be quantified through sparse (5 slices) sampling with DENSE. This consolidation significantly reduces the time required to assess both mass/volume-based measures of cardiac function and advanced cardiac mechanics. PMID:24923710

  6. Ergospirometry and Echocardiography in Early Stage of Heart Failure with Preserved Ejection Fraction and in Healthy Individuals

    PubMed Central

    Garcia, Eduardo Lima; Menezes, Márcio Garcia; Stefani, Charles de Moraes; Danzmann, Luiz Cláudio; Torres, Marco Antonio Rodrigues

    2015-01-01

    Background Heart failure with preserved ejection fraction is a syndrome characterized by changes in diastolic function; it is more prevalent among the elderly, women, and individuals with systemic hypertension (SH) and diabetes mellitus. However, in its early stages, there are no signs of congestion and it is identified in tests by adverse remodeling, decreased exercise capacity and diastolic dysfunction. Objective To compare doppler, echocardiographic (Echo), and cardiopulmonary exercise test (CPET) variables - ergospirometry variables - between two population samples: one of individuals in the early stage of this syndrome, and the other of healthy individuals. Methods Twenty eight outpatients diagnosed with heart failure according to Framingham’s criteria, ejection fraction > 50% and diastolic dysfunction according to the european society of cardiology (ESC), and 24 healthy individuals underwent Echo and CPET. Results The group of patients showed indexed atrial volume and left ventricular mass as well as E/E’ and ILAV/A´ ratios significantly higher, in addition to a significant reduction in peak oxygen consumption and increased VE/VCO2 slope, even having similar left ventricular sizes in comparison to those of the sample of healthy individuals. Conclusion There are significant differences between the structural and functional variables analyzed by Echo and CPET when comparing two population samples: one of patients in the early stage of heart failure with ejection fraction greater than or equal to 50% and another of healthy individuals. PMID:26247247

  7. The Association between Platelet/Lymphocyte Ratio and Coronary Artery Disease Severity in Asymptomatic Low Ejection Fraction Patients

    PubMed Central

    Açar, Burak; Gul, Murat; Özeke, Özcan; Aydogdu, Sinan

    2016-01-01

    Background and Objectives Coronary angiography (CAG) is generally needed in the setting of systolic heart failure (HF) with an unidentified etiology as a part of diagnostic strategy. On the other hand, the clinical value of this invasive strategy is largely unknown. Platelet-lymphocyte ratio (PLR) has recently emerged as a novel inflammatory index that may serve as an important predictor of inflammatory state and overall mortality. The present study aimed to search the predictive value of PLR in determining the extent of coronary atherosclerosis in asymptomatic low ejection fraction (EF) patients. Subjects and Methods 156 asymptomatic heart failure (HF) subjects (without angina or HF symptoms, mean age: 58 years; to male: 71.2%) were enrolled, and thereafter a CAG was performed. Gensini Score was used to determine the severity of coronary artery disease (CAD) on CAG. According to this scoring system, the overall study group was categorized into three distinct subgroups: control group with the score 0, mild atherosclerosis group with the score 0 to 20 and severe atherosclerosis group with the score of >20. Thereafter, a comparison was made among groups with regard to mean values of PLR. Results The severe atherosclerosis group had a substantially higher level of mean PLR in comparison to other groups (p<0.001). Pre-CAG PLR levels as well as a variety of clinical variables including age, low density lipoprotein (LDL)-cholesterol demonstrated an independent correlation with Gensini score through a multivariate analysis. Conclusion These findings suggest the potential association of high PLR levels with severe atherosclerosis in the setting of asymptomatic systolic HF. A simple measurement of PLR helps to identify the severity of coronary atherosclerosis prior to conducting coronary angiography. PMID:27826341

  8. Prognostic power of global 2D strain according to left ventricular ejection fraction in patients with ST elevation myocardial infarction

    PubMed Central

    Cha, Myung-Jin; Kim, Hyun-Sook; Kim, Seong Hwan; Park, Jae-Hyeong

    2017-01-01

    Backgrounds We aimed to evaluate the predictive power of longitudinal and circumferential fibers according to left ventricular ejection fraction (LVEF) in successfully reperfused acute ST elevation myocardial infarction (STEMI) patients. Methods Total 691 patients (age 59±13, 20% female) underwent clinical evaluation and conventional and strain echocardiography (Global longitudinal strain (GLS), global circumferential strain (GCS)). The clinical outcome was defined as the composite of death, hospitalization for heart failure, non-fatal myocardial infarction, and ventricular arrhythmia. Results During a follow-up of 39±19 months, there were 47 (6.8%) clinical events. In multivariate Cox models adjusted clinical risk factors, age (HR 1.08, p = 0.001) and GLS (HR 1.37, p = 0.001) were independent predictors. The addition of GLS resulted in significant incremental improvement in the predictive value on LVEF (χ2 = 31.8→45.8, p<0.001), although GCS offers no additional benefit. In the subgroup analysis according to LVEF, adjusted with clinical factors, GLS was significant predictive for outcome for the patients with mildly depressed (LVEF 40–50%, HR 2.25, p<0.001) and significantly depressed (LVEF<40%, HR 1.28, p = 0.016) systolic function, although GCS and LVEF lost their power with LVEF<40%. For the patients with preserved LVEF (>50%), GLS, GCS and LVEF did not show significant predictive power. Conclusions GLS is a most powerful predictor of outcome in successfully reperfused STEMI patients, especially with depressed LV dysfunction, although GCS and LVEF lost their predictive power for the patients with significantly depressed LV function. However, GLS did not predict outcome for the patients with preserved LVEF (>50%). PMID:28334029

  9. Mitral regurgitation in patients with coronary artery disease and low left ventricular ejection fractions. How should it be treated?

    PubMed Central

    Christenson, J T; Simonet, F; Maurice, J; Bloch, A; Velebit, V; Schmuziger, M

    1995-01-01

    In recent years, coronary artery bypass grafting has been extended to include patients with very low left ventricular ejection fractions. Should concomitant mitral valve regurgitation be corrected simultaneously? Between January 1990 and July 1994, 43 patients with preoperative left ventricular ejection fractions < or = 25% and echocardiographic evidence of concomitant mitral valve regurgitation (grade I, 18 patients; II, 19 patients; and III, 6 patients) underwent primary coronary artery bypass grafting. None of these patients underwent simultaneous mitral valve surgery. Twenty-four patients (56%) had pulmonary artery pressures > or = 40 mmHg (pulmonary hypertension). The mean preoperative left ventricular ejection fraction was 18.7% +/- 4.4% (range, 10% to 25%), and the mean pulmonary artery pressure was 45.6 +/- 15.8 mmHg. The average of number of grafts per patient was 4.5 +/- 1.5. Five patients underwent simultaneous repair of a left ventricular aneurysm. The hospital mortality rate was 4.7% (2/43). Transient low cardiac output occurred postoperatively in 13 patients (30%). Sixteen patients (37%) had no postoperative complications. The average follow-up of the 41 hospital survivors was 6 months (range, 1 to 32 months). One patient died 8 months after surgery for an overall mortality rate of 7%. Another 2 patients had graft occlusions that did not require reoperation. In the 40 surviving patients, follow-up echocardiography revealed that 37 patients (93%) had either no mitral valve regurgitation or only very mild mitral valve regurgitation (grade I). Three patients had grade II mitral valve regurgitation, but none required mitral valve surgery. The New York Heart Association functional class improved significantly in all hospital survivors (from 3.4 +/- 0.6 to 1.7 +/- 0.7; p > 0.001), and left ventricular ejection fractions rose from 19.0% +/- 4.6% to 42.0% +/- 8.3%. Coronary artery bypass grafting is possible in patients with very low left ventricular ejection

  10. Comparison and co-relation of invasive and noninvasive methods of ejection fraction measurement.

    PubMed Central

    Godkar, Darshan; Bachu, Kalyan; Dave, Bijal; Megna, Robert; Niranjan, Selva; Khanna, Ashok

    2007-01-01

    BACKGROUND: Accurate estimation of left ventricular ejection fraction (LVEF) has assumed great significance in the era of automatic implantable cardioverter defibrillators (AICDs), and a low EF may be one of the sole deciding factor in determining AICD implantation in certain patient populations. AIM: There are various methods, invasive and noninvasive, which can help calculate EF. We sought to conduct a retrospective study comparing EF estimation by invasive (angiography) and noninvasive methods [MUGA (multiple-gated acquisition), echocardiography (echo), single-photon emission computed tomography (SPECT)] in 5,558 patients in our hospital from 1995-2004. METHODS AND RESULTS: EF was estimated by > or = 1 method (angiography, MUGA, echo, SPECT) within a one-month period. Values for the four tests in 5,558 patients were as follows: angiography mean 46.2, range 20-75, standard deviation (SD) 13.1; MUGA mean 45.7, range 20-70, SD 11.6; echo mean 45.7, range 22-70, SD 11.2; and SPECT mean 54.4, range 30-75, SD 11.9. Excellent positive correlations were found among all four tests as follows: angiography and MUGA, correlation coefficient (r) = 0.97, angiography and echo r = 0.96, angiography and SPECT r = 0.94, MUGA and echo r = 0.97, MUGA and SPECT r = 0.94, and echo and SPECT r = 0.94. Values for SPECT were significantly higher than for angiography, echo and MUGA (p < 0.001). The arithmetic difference between angiography and MUGA (mean 0.50, range -5.0-5.0) and the arithmetic difference between angiography and echo (mean 0.52, range -5.0-15.0) were similar (p = 0.59). The arithmetic difference between SPECT and angiography (mean 8.2, range -15.0-20.0) was significantly larger than the arithmetic difference between angiography and echo (p < 0.001). CONCLUSIONS: All the four methods used to estimate EF corelate well with each other. However, values estimated during stress testing by SPECT overestimate EF and are significantly higher as compared to MUGA, echo and

  11. Effects of Sildenafil on Ventricular and Vascular Function in Heart Failure With Preserved Ejection Fraction

    PubMed Central

    Borlaug, Barry A.; Lewis, Gregory D.; McNulty, Steven E.; Semigran, Marc J.; LeWinter, Martin; Chen, Horng; Lin, Grace; Deswal, Anita; Margulies, Kenneth B.; Redfield, Margaret M.

    2015-01-01

    Background Early studies showed beneficial effects of phosphodiesterase 5 inhibitors (PDE5i) on cardiovascular function in heart failure (HF) patients, but the RELAX trial observed no improvement in exercise capacity with sildenafil treatment in subjects with HF and preserved ejection fraction (HFpEF). Methods and Results A subgroup of participants in the RELAX trial (n=48) underwent comprehensive noninvasive cardiovascular assessment before and after treatment with sildenafil or placebo in a prospective ancillary study. Left ventricular (LV) contractility was assessed by peak power index (PWR/EDV) and stroke work index (SW/EDV). Systemic arterial load was assessed by arterial elastance (Ea) and right ventricular afterload by pulmonary artery systolic pressure (PASP). Endothelial function was assessed by reactive hyperemia index (RHI) following upper arm cuff occlusion. Compared to placebo (n=25), sildenafil (n=23) decreased Ea (−0.29±0.28mmHg/ml vs +0.02±0.29, p=0.008) and tended to improve RHI (+0.30±0.45 vs −0.17±0.30, p=0.054). In contrast, LV contractility was reduced by 11–16% with sildenafil compared to placebo (ΔPWR/EDV −52±70 vs +0±40 mmHg/s, p=0.006; ΔSW/EDV +0.3±5.8 vs −6.0±5.1 mmHg, p=0.04). Sildenafil had no effect on PASP. Conclusions In subjects with HFpEF, sildenafil displayed opposing effects on ventricular and vascular function. We speculate that beneficial effects of PDE5i in the systemic vasculature and endothelium were insufficient to improve clinical status, or that the deleterious effects on left ventricular function offset any salutary vascular effects, contributing to the absence of benefit observed with sildenafil in subjects with HFpEF in the RELAX trial. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00094302. PMID:25782985

  12. Assessing Strategies for Heart Failure with Preserved Ejection Fraction at the Outpatient Clinic

    PubMed Central

    Jorge, Antonio José Lagoeiro; Rosa, Maria Luiza Garcia; Ribeiro, Mario Luiz; Fernandes, Luiz Claudio Maluhy; Freire, Monica Di Calafiori; Correia, Dayse Silva; Teixeira, Patrick Duarte; Mesquita, Evandro Tinoco

    2014-01-01

    Background: Heart failure with preserved ejection fraction (HFPEF) is the most common form of heart failure (HF), its diagnosis being a challenge to the outpatient clinic practice. Objective: To describe and compare two strategies derived from algorithms of the European Society of Cardiology Diastology Guidelines for the diagnosis of HFPEF. Methods: Cross-sectional study with 166 consecutive ambulatory patients (67.9±11.7 years; 72% of women). The strategies to confirm HFPEF were established according to the European Society of Cardiology Diastology Guidelines criteria. In strategy 1 (S1), tissue Doppler echocardiography (TDE) and electrocardiography (ECG) were used; in strategy 2 (S2), B-type natriuretic peptide (BNP) measurement was included. Results: In S1, patients were divided into groups based on the E/E'ratio as follows: GI, E/E'> 15 (n = 16; 9%); GII, E/E'8 to 15 (n = 79; 48%); and GIII, E/E'< 8 (n = 71; 43%). HFPEF was confirmed in GI and excluded in GIII. In GII, TDE [left atrial volume index (LAVI) ≥ 40 mL/m2; left ventricular mass index LVMI) > 122 for women and > 149 g/m2 for men] and ECG (atrial fibrillation) parameters were assessed, confirming HFPEF in 33 more patients, adding up to 49 (29%). In S2, patients were divided into three groups based on BNP levels. GI (BNP > 200 pg/mL) consisted of 12 patients, HFPEF being confirmed in all of them. GII (BNP ranging from 100 to 200 pg/mL) consisted of 20 patients with LAVI > 29 mL/m2, or LVMI ≥ 96 g/m2 for women or ≥ 116 g/m2 for men, or E/E'≥ 8 or atrial fibrillation on ECG, and the diagnosis of HFPEF was confirmed in 15. GIII (BNP < 100 pg/mL) consisted of 134 patients, 26 of whom had the diagnosis of HFPEF confirmed when GII parameters were used. Measuring BNP levels in S2 identified 4 more patients (8%) with HFPEF as compared with those identified in S1. Conclusion: The association of BNP measurement and TDE data is better than the isolated use of those parameters. BNP can be useful in

  13. Treating Heart Failure with Preserved Ejection Fraction Related to Arterial Stiffness. Can we Kill Two Birds With One Stone?

    PubMed

    Athyros, Vasilios G; Pagourelias, Efstathios D; Gossios, Thomas D; Vasilikos, Vasilios G

    2015-01-01

    Heart failure with preserved ejection fraction (HFpEF). Arterial hypertension (AH), arterial stiffness (AS), older age, and female gender are the main determinants of HFpEF, but several cardiac or extra-cardiac pathologies are also possible causes. The combined ventricular-vascular stiffening (abnormal left atrium-left ventricle coupling related to AS) is the main contributor of the increased prevalence of HFpEF in elderly persons, particularly elderly women, and in younger persons with AH. The hospitalization and mortality rates of HFpEF are similar to those of heart failure with reduced EF (HFrEF). However, although the prognosis of HFrEF has been substantially improved during the last 2 decades, the effective treatment of HFpEF remains an unmet need. Regimens effective in HFrEF have no substantial effect on HFpEF, because of different pathophysiologies of the 2 syndromes. Pipeline drugs seem promising, but it will take some years before they are commercially available. Aggressive treatment of noncardiac comorbidities seems to be the only option at hand. Treatment of anaemia, sleep disorders, chronic kidney disease (CKD), non-alcoholic fatty liver (NAFLD), atrial fibrillation, diabetes, and careful use of diuretics to reduce preload are effective to some degree. Statin treatment, despite the presence of dyslipidaemia, deserves special attention because it has been proven, mainly in small studies or post hoc analyses of trials, that it offers a substantial improvement in quality of life and a reduction in mortality rates. We need to urgently utilize these recourses to relieve a considerable part of the general population suffering from HFpEF, a deadly disease.

  14. Skeletal muscle composition and its relation to exercise intolerance in older patients with heart failure and preserved ejection fraction.

    PubMed

    Haykowsky, Mark J; Kouba, Erik J; Brubaker, Peter H; Nicklas, Barbara J; Eggebeen, Joel; Kitzman, Dalane W

    2014-04-01

    Exercise intolerance is the primary chronic symptom in heart failure with preserved ejection fraction (HFpEF), the most common form of heart failure in older patients; however its pathophysiology is not well understood. Recent data suggest that peripheral factors such as skeletal muscle (SM) dysfunction may be important contributors. Therefore, 38 participants, 23 patients with HFpEF (69±7 years) and 15 age-matched healthy controls (HCs), underwent magnetic resonance imaging and cardiopulmonary exercise testing to assess for SM, intermuscular fat (IMF), subcutaneous fat, total thigh, and thigh compartment (TC) areas and peak exercise oxygen consumption (peak VO2). There were no significant intergroup differences in total thigh area, TC, subcutaneous fat, or SM. However, in the HFpEF versus HC group, IMF area (35.6±11.5 vs 22.3±7.6 cm2, p=0.01), percent IMF/TC (26±5 vs 20±5%, p=0.005), and the ratio of IMF/SM (0.38±0.10 vs 0.28±0.09, p=0.007) were significantly increased, whereas percent SM/TC was significantly reduced (70±5 vs 75±5, p=0.009). In multivariate analyses, IMF area (partial r=-0.51, p=0.002) and IMF/SM ratio (partial r=-0.45, p=0.006) were independent predictors of peak VO2 whereas SM area was not (partial r = -0.14, p=0.43). Thus, older patients with HFpEF have greater thigh IMF and IMF/SM ratio compared with HCs, and these are significantly related to their severely reduced peak VO2. These data suggest that abnormalities in SM composition may contribute to the severely reduced exercise capacity in older patients with HFpEF. This implicates potential targets for novel therapeutic strategies in this common debilitating disorder of older persons.

  15. Screening for Cardiac Magnetic Resonance Scar Features by 12-lead ECG, in Patients with Preserved Ejection Fraction

    PubMed Central

    Mewton, Nathan; Strauss, David G.; Rizzi, Patricia; Verrier, Richard L.; Liu, Chia Ying; Tereshchenko, Larisa G.; Nearing, Bruce; Volpe, Gustavo J.; Marchlinski, Francis E.; Moxley, John; Killian, Tony; Wu, Katherine C.; Spooner, Peter; Lima, João A.C.

    2015-01-01

    Background Increased QRS score and wide spatial QRS-T angle are independent predictors of cardiovascular mortality in the general population. Our main objective was to assess whether a QRS score ≥5 and/or QRS-T angle ≥105° enable screening of patients for myocardial scar features. Methods 77 patients age ≤70 years with QRS score ≥5 AND/OR spatial QRS-T angle ≥105° as well as left ventricular ejection fraction (LVEF) >35% were enrolled in the study. All participants underwent complete clinical examination, signal averaged ECG (SAECG), 30-minute ambulatory ECG recording for T wave alternans (TWA), and late gadolinium enhancement cardiac magnetic resonance (LGE-CMR). Relationship between QRS score, QRS-T angle with scar presence and pattern, as well as gray zone, core, and total scar size by LGE-CMR were assessed. Results Myocardial scar was present in 41 (53%) patients, of whom 19 (46%) exhibited a typical ischemic pattern. QRS score but not QRS-T angle was related to total scar size and gray zone size (R2=0.12, P=0.002; R2=0.17; P ≤0.0001 respectively). Patients with QRS scores ≥6 had significantly greater myocardial scar and gray zone size, increased QRS duration and QRS-T angle, a higher prevalence of late potentials (LP) presence, increased LV end-diastolic volume and decreased LVEF. There was a significant independent and positive association between TWA value and total scar (P=0.001) and gray zone size (P=0.01). Conclusion Patients with preserved LVEF and myocardial scar by CMR also have electrocardiographic features that could be involved in ventricular arrhythmogenesis. PMID:26806840

  16. Comparison of Causes of Death After Heart Transplantation in Patients With Left Ventricular Ejection Fractions ≤35% Versus >35.

    PubMed

    Birati, Edo Y; Mathelier, Hansie; Molina, Maria; Hanff, Thomas C; Mazurek, Jeremy A; Atluri, Pavan; Acker, Michael A; Rame, J Eduardo; Margulies, Kenneth B; Goldberg, Lee R; Jessup, Mariell

    2016-04-15

    Sudden cardiac death (SCD) is a common cause of death in the general population, occurring in 300,000 to 350,000 people in the United States alone. Currently, there are no data supporting implantable cardioverter-defibrillator therapy in patients who underwent orthotopic heart transplant (OHT) with low left ventricular ejection fraction (LVEF). In this retrospective study, we included all patients who underwent primary OHT at our institution from 2007 to 2013. We compared the cause of death in patients who underwent OHT and evaluated the correlation of the cause of death and the patients' LVEF. Our objectives were to determine whether patients who underwent OHT with LVEF <35% are at increased risk for SCD compared with those who underwent OHT with normal LVEF. To summarize our results, a total of 345 patients were included in our study (mean age 50 ± 14 years, 68% men). The mean follow-up was 1,260 ± 698 days. Forty patients (11.5%) died >6 months after OHT. Surviving patients had higher LVEF compared with deceased patients (64 ± 7% and 50 ± 24%, respectively, p ≤0.001). In all, 10 (25%) of the deceased patients died suddenly, 9 (23%) from sepsis, and 8 (20%) from malignancy. Of the 11 deceased patients with LVEF ≤35%, 2 patients (18%) died suddenly compared with 9 SCDs among the 29 deceased patients (31%) with LVEF >35% (p = 0.54). In conclusion, patients who underwent OHT who died were more likely to have LVEF <35%, and a quarter of the deceased patients who underwent OHT died suddenly. A reduced LVEF was not associated with an increased risk of SCD.

  17. Uptitration of renin-angiotensin system blocker and beta-blocker therapy in patients hospitalized for heart failure with reduced versus preserved left ventricular ejection fractions.

    PubMed

    Verbrugge, Frederik H; Duchenne, Jürgen; Bertrand, Philippe B; Dupont, Matthias; Tang, W H Wilson; Mullens, Wilfried

    2013-12-15

    In ambulatory patients with heart failure (HF) and reduced ejection fraction (rEF), renin-angiotensin system (RAS) and β-blockers at guideline-recommended target dose reduce all-cause mortality and readmissions. Benefits in HF with preserved ejection fraction (pEF), as well as uptitration after a hospitalization, remain uncertain. This study assesses the impact of RAS- and β-blocker uptitrations in patients with HFrEF versus HFpEF during and immediately after a hospital admission. In consecutive patients (209 HFrEF with left ventricular ejection fraction <40% and 108 HFpEF with left ventricular ejection fraction ≥40%), RAS- and β-blocker dose changes were followed during 6 months after an index HF hospitalization. Patients with a RAS- and β-blocker dose increase of ≥10% of the recommended target dose were compared with patients without uptitration. Patients who received uptitration were significantly younger, with a higher heart rate and better renal function, and received spironolactone more often. Both RAS- and β-blocker uptitrations were associated with significant reductions in the composite end-point of all-cause mortality or HF readmissions in HFrEF (hazard ratio [HR] 0.36, 95% confidence interval [CI] 0.22 to 0.60 and HR 0.51, 95% CI 0.32 to 0.81, respectively). After correction for age, heart rate, blood pressure, renal function, and spironolactone use, this association remained significant for RAS blockers (HR 0.54, 95% CI 0.31 to 0.93, p = 0.027) but not for β-blockers (HR 0.65, 95% CI 0.39 to 1.09, p = 0.101). No benefit of RAS- or β-blocker uptitration was observed in HFpEF. In conclusion, uptitration of neurohumoral blockers after an HF hospitalization is more frequently performed in younger patients with low co-morbidity burden. RAS-blocker uptitration independently predicts clinical outcome in patients with HFrEF but not in those with HFpEF.

  18. The Fraction of Interplanetary Coronal Mass Ejections That Are Magnetic Clouds: Evidence for a Solar Cycle Variation

    NASA Technical Reports Server (NTRS)

    Richardson, I. G.; Cane, H. V.

    2004-01-01

    "Magnetic clouds" (MCs) are a subset of interplanetary coronal mass ejections (ICMEs) characterized by enhanced magnetic fields with an organized rotation in direction, and low plasma beta. Though intensely studied, MCs only constitute a fraction of all the ICMEs that are detected in the solar wind. A comprehensive survey of ICMEs in the near- Earth solar wind during the ascending, maximum and early declining phases of solar cycle 23 in 1996 - 2003 shows that the MC fraction varies with the phase of the solar cycle, from approximately 100% (though with low statistics) at solar minimum to approximately 15% at solar maximum. A similar trend is evident in near-Earth observations during solar cycles 20 - 21, while Helios 1/2 spacecraft observations at 0.3 - 1.0 AU show a weaker trend and larger MC fraction.

  19. Evidence Supporting the Existence of a Distinct Obese Phenotype of Heart Failure with Preserved Ejection Fraction.

    PubMed

    Obokata, Masaru; Reddy, Yogesh N V; Pislaru, Sorin V; Melenovsky, Vojtech; Borlaug, Barry A

    2017-04-05

    Background -Heart failure (HF) with preserved ejection fraction (HFpEF) is a heterogeneous syndrome. Phenotyping patients into pathophysiologically homogenous groups may enable better targeting of treatment. Obesity is common in HFpEF and has many cardiovascular effects, suggesting it may be a viable candidate for phenotyping. We compared cardiovascular structure, function, and reserve capacity in subjects with obese HFpEF, non-obese HFpEF, and controls. Methods -Subjects with obese HFpEF (BMI≥35kg/m(2), n=99), non-obese HFpEF (BMI<30kg/m(2), n=96), and non-obese controls free of HF (n=71) underwent detailed clinical assessment, echocardiography and invasive hemodynamic exercise testing. Results -Compared to both non-obese HFpEF and controls, subjects with obese HFpEF displayed increased plasma volume (3907 [3563,4333] vs. 2772 [2555,3133] and 2680 [2380,3006] ml, p<0.0001), more concentric left ventricular remodeling, greater right ventricular dilatation (base 34±7 vs. 31±6 and 30±6 mm, p=0.0005; length 66±7 vs. 61±7 and 61±7 mm, p<0.0001), more right ventricular dysfunction, increased epicardial fat thickness (10±2 vs. 7±2 and 6±2 mm, p<0.0001), and greater total epicardial heart volume (945 [831,1105] vs. 797 [643,979] and 632 [517,768] ml, p<0.0001), despite lower NT-proBNP levels. Pulmonary capillary wedge pressure was correlated with body mass and plasma volume in obese HFpEF (r=0.22 and 0.27, both p<0.05), but not in non-obese HFpEF (p≥0.3). The increase in heart volumes in obese HFpEF was associated with greater pericardial restraint and heightened ventricular interdependence, reflected by increased ratio of right to left heart filling pressures (0.64±0.17 vs. 0.56±0.19 and 0.53±0.20, p=0.0004), higher pulmonary venous pressure relative to left ventricular transmural pressure, and greater left ventricular eccentricity index (1.10±0.19 vs 0.99±0.06 and 0.97±0.12, p<0.0001). Interdependence was enhanced as pulmonary artery pressure load

  20. Beta-Adrenergic Blockade Therapy for Autonomic Dysfunction is Less Effective for Elderly Patients with Heart Failure and Reduced Left Ventricular Ejection Fraction

    PubMed Central

    Shimamoto, Ken; Kawana, Masatoshi

    2015-01-01

    OBJECTIVE Heart rate variability (HRV) has been reported to be an independent predictor of all-cause and sudden cardiac death in patients with heart failure. In the aging heart, however, both autonomic and cardiac functions appear to be altered. We assessed the relationship between aging and responsiveness of HRV and ventricular remodeling to beta-adrenergic blockade therapy in patients with heart failure and reduced ejection fraction (HFREF). METHODS Twenty-eight clinically stable patients with chronic heart failure, sinus rhythm, and left ventricular ejection fraction <50% as confirmed by echocardiography were included. At baseline and after carvedilol treatment, 24-hour ambulatory Holter monitor recording was used to analyze HRV indices by the maximum entropy method. Changes in these parameters were compared among three age groups. RESULTS HR decreased in all groups after carvedilol treatment, but was still highest in the youngest group despite the same treatment doses. Time and frequency domain variables improved. The response of time domain variables (the standard deviation of all normal sinus to normal sinus [NN] intervals and the standard deviation of the averages of NN intervals in all 5-minute or 30-minute segments) to carvedilol therapy significantly decreased with increasing age. Ventricular reverse remodeling induced by carvedilol therapy significantly decreased with increasing age. Increases in time domain variables and a low-frequency domain moderately correlated with left ventricular reverse remodeling. CONCLUSION Beta-adrenergic blockade therapy improved HRV variables and ventricular remodeling in HFREF patients; however, the response tended to be milder in the elderly. HRV improvement was associated with ventricular reverse remodeling. PMID:26483614

  1. Thirty Years of Evidence on the Efficacy of Drug Treatments for Chronic Heart Failure With Reduced Ejection Fraction

    PubMed Central

    Earley, Amy; Voors, Adriaan A.; Senni, Michele; McMurray, John J.V.; Deschaseaux, Celine; Cope, Shannon

    2017-01-01

    Background— Treatments that reduce mortality and morbidity in patients with heart failure with reduced ejection fraction, including angiotensin-converting enzyme inhibitors (ACEI), angiotensin receptor blockers (ARB), β-blockers (BB), mineralocorticoid receptor antagonists (MRA), and angiotensin receptor–neprilysin inhibitors (ARNI), have not been studied in a head-to-head fashion. This network meta-analysis aimed to compare the efficacy of these drugs and their combinations regarding all-cause mortality in patients with heart failure with reduced ejection fraction. Methods and Results— A systematic literature review identified 57 randomized controlled trials published between 1987 and 2015, which were compared in terms of study and patient characteristics, baseline risk, outcome definitions, and the observed treatment effects. Despite differences identified in terms of study duration, New York Heart Association class, ejection fraction, and use of background digoxin, a network meta-analysis was considered feasible and all trials were analyzed simultaneously. The random-effects network meta-analysis suggested that the combination of ACEI+BB+MRA was associated with a 56% reduction in mortality versus placebo (hazard ratio 0.44, 95% credible interval 0.26–0.66); ARNI+BB+MRA was associated with the greatest reduction in all-cause mortality versus placebo (hazard ratio 0.37, 95% credible interval 0.19–0.65). A sensitivity analysis that did not account for background therapy suggested that ARNI monotherapy is more efficacious than ACEI or ARB monotherapy. Conclusions— The network meta-analysis showed that treatment with ACEI, ARB, BB, MRA, and ARNI and their combinations were better than the treatment with placebo in reducing all-cause mortality, with the exception of ARB monotherapy and ARB plus ACEI. The combination of ARNI+BB+MRA resulted in the greatest mortality reduction. PMID:28087688

  2. The value of the QRS scoring system in assessing regional and global left ventricular ejection fraction early after myocardial infarction.

    PubMed

    Bergovec, M; Prpìć, H; Mihatov, S; Zigman, M; Vukosavić, D; Birtić, K; Franceschi, D; Barić, L

    1993-08-01

    In 71 patients with a myocardial infarction (MI) (anterior in 27, inferior in 44 patients) global (GEF) and regional (REF) left ventricular ejection fractions were determined by radionuclide ventriculography and estimated from a 12 lead electrocardiogram (ECG), using Selvester's QRS score, during the early phase of a MI (15 to 21 days following MI). Global ejection fractions determined by radionuclide ventriculography and from ECG using Palmeri's method were: for all MI 40.8 +/- 12.6% vs 39.6 +/- 11.4%; in the group of anterior MI 32.0 +/- 10.0% vs 30.0 +/- 9.7% and in the group of inferior MI 48.9 +/- 12.0% vs 45.1 +/- 8.2%. A good correlation was found between global ejection fractions determined by radionuclide ventriculography and ECG, as well as between radionuclide GEF and ECG score. A weaker correlation was found between radionuclide GEF and enzymes among all MIs and in the group of anterior MI, while in the group of inferior MI this correlation was insignificant. The analysis of REF determined by radionuclide ventriculography and ECG showed the greatest abnormalities in the infarct region, but in the group of anterior MI, dysfunction was present in the whole left ventricle. The comparison of infarct-related REF derived from radionuclide ventriculography, with the QRS score showed a significantly higher correlation than the comparison with enzymes. ECG estimation of REF from a modified Palmeri's equation showed a better correlation with radionuclide REF than did GEF derived from the standard Palmeri's equation: anterior MI; r = 0.90 vs r = 0.82, inferior MI; r = 0.84 vs r = 0.69, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Cognitive Function in Ambulatory Patients with Systolic Heart Failure: Insights from the Warfarin versus Aspirin in Reduced Cardiac Ejection Fraction (WARCEF) Trial

    PubMed Central

    Graham, Susan; Ye, Siqin; Qian, Min; Sanford, Alexandra R.; Di Tullio, Marco R.; Sacco, Ralph L.; Mann, Douglas L.; Levin, Bruce; Pullicino, Patrick M.; Freudenberger, Ronald S.; Teerlink, John R.; Mohr, J. P.; Labovitz, Arthur J.; Lip, Gregory Y. H.; Estol, Conrado J.; Lok, Dirk J.; Ponikowski, Piotr; Anker, Stefan D.; Thompson, John L. P.; Homma, Shunichi

    2014-01-01

    We sought to determine whether cognitive function in stable outpatients with heart failure (HF) is affected by HF severity. A retrospective, cross-sectional analysis was performed using data from 2, 043 outpatients with systolic HF and without prior stroke enrolled in the Warfarin versus Aspirin in Reduced Cardiac Ejection Fraction (WARCEF) Trial. Multivariable regression analysis was used to assess the relationship between cognitive function measured using the Mini-Mental Status Exam (MMSE) and markers of HF severity (left ventricular ejection fraction [LVEF], New York Heart Association [NYHA] functional class, and 6-minute walk distance). The mean (SD) for the MMSE was 28.6 (2.0), with 64 (3.1%) of the 2,043 patients meeting the cut-off of MMSE <24 that indicates need for further evaluation of cognitive impairment. After adjustment for demographic and clinical covariates, 6-minute walk distance (β-coefficient 0.002, p<0.0001), but not LVEF or NYHA functional class, was independently associated with the MMSE as a continuous measure. Age, education, smoking status, body mass index, and hemoglobin level were also independently associated with the MMSE. In conclusion, six-minute walk distance, but not LVEF or NYHA functional class, was an important predictor of cognitive function in ambulatory patients with systolic heart failure. PMID:25426862

  4. Cosmic Ray Exposure Ages of Nakhlites — Nakhla, Lafayette, Governador Valadares — and Chassigny: One Ejection Event?

    NASA Astrophysics Data System (ADS)

    Korochantseva, E. V.; Schwenzer, S. P.; Buikin, A. I.; Hopp, J.; Ott, U.; Trieloff, M.

    2011-03-01

    To provide further insight into the vigorously discussed question if all nakhlites and Chassigny were ejected by the same impact event from a common martian location, we present new CRE ages for nakhlites and Chassigny obtained by different methods.

  5. End-systolic Pressure-Volume Relation, Ejection Fraction, and Heart Failure: Theoretical Aspect and Clinical Applications.

    PubMed

    Shoucri, Rachad M

    2015-01-01

    A mathematical formalism describing the nonlinear end-systolic pressure-volume relation (ESPVR) is used to derive new indexes that can be used to assess the performance of the heart left ventricle by using the areas under the ESPVR (units of energy), the ordinates of the ESPVR (units of pressure), or from slopes of the curvilinear ESPVR. New relations between the ejection fraction (EF) and the parameters describing the ESPVR give some insight into the problem of heart failure (HF) with normal or preserved ejection fraction. Relations between percentage occurrence of HF and indexes derived from the ESPVR are also discussed. When ratios of pressures are used, calculation can be done in a noninvasive way with the possibility of interesting applications in routine clinical work. Applications to five groups of clinical data are given and discussed (normal group, aortic stenosis, aortic valvular regurgitation, mitral valvular regurgitation, miscellaneous cardiomyopathies). No one index allows a perfect segregation between all clinical groups, it is shown that appropriate use of two indexes (bivariate analysis) can lead to better separation of different clinical groups.

  6. Changing the treatment of heart failure with reduced ejection fraction: clinical use of sacubitril-valsartan combination

    PubMed Central

    Kaplinsky, Edgardo

    2016-01-01

    Despite significant therapeutic advances, patients with chronic heart failure (HF) remain at high risk of morbidity and mortality. Sacubitril valsartan (previously known as LCZ696) is a new oral agent approved for the treatment of symptomatic chronic heart failure in adults with reduced ejection fraction. It is described as the first in class angiotensin receptor neprilysin inhibitor (ARNI) since it incorporates the neprilysin inhibitor, sacubitril and the angiotensin II receptor antagonist, valsartan. Neprilysin is an endopeptidase that breaks down several vasoactive peptides including natriuretic peptides (NPs), bradykinin, endothelin and angiotensin II (Ang-II). Therefore, a natural consequence of its inhibition is an increase of plasmatic levels of both, NPs and Ang-II (with opposite biological actions). So, a combined inhibition of these both systems (Sacubitril / valsartan) may enhance the benefits of NPs effects in HF (natriuresis, diuresis, etc) while Ang-II receptor is inhibited (reducing vasoconstriction and aldosterone release). In a large clinical trial (PARADIGM-HF with 8442 patients), this new agent was found to significantly reduce cardiovascular and all cause mortality as well as hospitalizations due to HF (compared to enalapril). This manuscript reviews clinical evidence for sacubitril valsartan, dosing and cautions, future directions and its considered place in the therapy of HF with reduced ejection fraction. PMID:28133468

  7. The acute effects of low flow oxygen and isosorbide dinitrate on left and right ventricular ejection fractions in chronic obstructive pulmonary disease

    SciTech Connect

    Morrison, D.; Caldwell, J.; Lakshminaryan, S.; Ritchie, J.L.; Kennedy, J.W.

    1983-10-01

    The objectives of this study were to determine the effects of low flow oxygen and isosorbide dinitrate on rest and exercise biventricular ejection fractions in patients with chronic obstructive pulmonary disease and to relate these ejection fraction responses to changes in pressure and flow. Nine patients with stable, moderate to severe chronic obstructive pulmonary disease who had no prior history of heart failure performed supine exercise with simultaneous hemodynamic and radionuclide ventriculographic monitoring. Eight patients performed a second exercise during low flow oxygen breathing and five performed a third exercise after ingesting 10 mg oral isosorbide. Oxygen led to a decrease in exercise pulmonary artery pressure in all subjects and a decline in total pulmonary resistance in five of the seven in whom it was measured. Right ventricular ejection fraction increased 0.05 or more only in subjects who had a decrease in total pulmonary resistance. Isosorbide led to an increase in rest and exercise right and left ventricular ejection fractions with simultaneous decreases in pulmonary artery pressure, total pulmonary resistance, blood pressure and arterial oxygen tension. These results suggest that in patients with chronic obstructive pulmonary disease but without a history of right heart failure, the right ventricular systolic functional response to low flow oxygen and isosorbide at rest and exercise is, in part, determined by changes in total pulmonary resistance. The chronic relation between right ventricular ejection fraction and pulmonary hemodynamics in patients with chronic obstructive pulmonary disease remains to be evaluated.

  8. Risk Related to Pre–Diabetes Mellitus and Diabetes Mellitus in Heart Failure With Reduced Ejection Fraction

    PubMed Central

    Kristensen, Søren L.; Preiss, David; Jhund, Pardeep S.; Squire, Iain; Cardoso, José Silva; Merkely, Bela; Martinez, Felipe; Starling, Randall C.; Desai, Akshay S.; Lefkowitz, Martin P.; Rizkala, Adel R.; Rouleau, Jean L.; Shi, Victor C.; Solomon, Scott D.; Swedberg, Karl; Zile, Michael R.; Packer, Milton

    2016-01-01

    Background— The prevalence of pre–diabetes mellitus and its consequences in patients with heart failure and reduced ejection fraction are not known. We investigated these in the Prospective Comparison of ARNI With ACEI to Determine Impact on Global Mortality and Morbidity in Heart Failure (PARADIGM-HF) trial. Methods and Results— We examined clinical outcomes in 8399 patients with heart failure and reduced ejection fraction according to history of diabetes mellitus and glycemic status (baseline hemoglobin A1c [HbA1c]: <6.0% [<42 mmol/mol], 6.0%–6.4% [42–47 mmol/mol; pre–diabetes mellitus], and ≥6.5% [≥48 mmol/mol; diabetes mellitus]), in Cox regression models adjusted for known predictors of poor outcome. Patients with a history of diabetes mellitus (n=2907 [35%]) had a higher risk of the primary composite outcome of heart failure hospitalization or cardiovascular mortality compared with those without a history of diabetes mellitus: adjusted hazard ratio, 1.38; 95% confidence interval, 1.25 to 1.52; P<0.001. HbA1c measurement showed that an additional 1106 (13% of total) patients had undiagnosed diabetes mellitus and 2103 (25%) had pre–diabetes mellitus. The hazard ratio for patients with undiagnosed diabetes mellitus (HbA1c, >6.5%) and known diabetes mellitus compared with those with HbA1c<6.0% was 1.39 (1.17–1.64); P<0.001 and 1.64 (1.43–1.87); P<0.001, respectively. Patients with pre–diabetes mellitus were also at higher risk (hazard ratio, 1.27 [1.10–1.47]; P<0.001) compared with those with HbA1c<6.0%. The benefit of LCZ696 (sacubitril/valsartan) compared with enalapril was consistent across the range of HbA1c in the trial. Conclusions— In patients with heart failure and reduced ejection fraction, dysglycemia is common and pre–diabetes mellitus is associated with a higher risk of adverse cardiovascular outcomes (compared with patients with no diabetes mellitus and HbA1c <6.0%). LCZ696 was beneficial compared with enalapril

  9. Connecting heart failure with preserved ejection fraction and renal dysfunction: the role of endothelial dysfunction and inflammation.

    PubMed

    Ter Maaten, Jozine M; Damman, Kevin; Verhaar, Marianne C; Paulus, Walter J; Duncker, Dirk J; Cheng, Caroline; van Heerebeek, Loek; Hillege, Hans L; Lam, Carolyn S P; Navis, Gerjan; Voors, Adriaan A

    2016-06-01

    Renal dysfunction in heart failure with preserved ejection fraction (HFpEF) is common and is associated with increased mortality. Impaired renal function is also a risk factor for developing HFpEF. A new paradigm for HFpEF, proposing a sequence of events leading to myocardial remodelling and dysfunction in HFpEF, was recently introduced, involving inflammatory, microvascular, and cardiac components. The kidney might play a key role in this systemic process. Renal impairment causes metabolic and systemic derangements in circulating factors, causing an activated systemic inflammatory state and endothelial dysfunction, which may lead to cardiomyocyte stiffening, hypertrophy, and interstitial fibrosis via cross-talk between the endothelium and cardiomyocyte compartments. Here, we review the role of endothelial dysfunction and inflammation to explain the link between renal dysfunction and HFpEF, which allows for identification of new early risk markers, prognostic factors, and unique targets for intervention.

  10. [Heart failure with preserved ejection fraction (HFPEF). Impact of change in the paradigm of isolated diastolic dysfunction].

    PubMed

    Magaña-Serrano, José Antonio; Rosas-Peralta, Martín; Candanosa-Arias, Carlos; Valencia-Sánchez, Salvador; Garrido-Garduño, Martín; Arriaga-Nava, Roberto; Calderón-Abbo, Moisés C

    2015-01-01

    Heart failure with preserved ejection fraction is a significant and growing public health problem, since it currently represents half of all patients with heart failure. Despite improvements in the understanding of the disease, there is no benefit form treatments tested at all. Advances in diagnostic imaging and invasive evaluation algorithms will allow a more accurate and early diagnosis so that treatment of earliest forms in the progression of the disease are applied since the potential for benefit may be higher. Although important progress has been made in our understanding of the pathophysiology, cardiac catheterization, and cellular of diastolic failure mechanisms and not diastolic mechanisms of disease, further research is required promptly to determine how best to address these anomalies to reduce the significant burden of morbidity and mortality in this form of heart failure, which is reaching pandemic proportions.

  11. Determination of left ventricular volume, ejection fraction, and myocardial mass by real-time three-dimensional echocardiography

    NASA Technical Reports Server (NTRS)

    Qin, J. X.; Shiota, T.; Thomas, J. D.

    2000-01-01

    Reconstructed three-dimensional (3-D) echocardiography is an accurate and reproducible method of assessing left ventricular (LV) functions. However, it has limitations for clinical study due to the requirement of complex computer and echocardiographic analysis systems, electrocardiographic/respiratory gating, and prolonged imaging times. Real-time 3-D echocardiography has a major advantage of conveniently visualizing the entire cardiac anatomy in three dimensions and of potentially accurately quantifying LV volumes, ejection fractions, and myocardial mass in patients even in the presence of an LV aneurysm. Although the image quality of the current real-time 3-D echocardiographic methods is not optimal, its widespread clinical application is possible because of the convenient and fast image acquisition. We review real-time 3-D echocardiographic image acquisition and quantitative analysis for the evaluation of LV function and LV mass.

  12. [Valvular surgery for an exercise-induced functional mitral regurgitation in heart failure and preserved ejection fraction: a case study].

    PubMed

    Attari, M; Legrand, M; Philippe, C; Rosak, P

    2013-08-01

    We here report the case of a 67-year-old woman with moderate mitral regurgitation without significant structural abnormalities that get worse during severe recurrent heart failures and preserved ejection fraction with concomitant paroxysmal atrial fibrillation. Atrial fibrillation became permanent and despite a well-controlled cardiac frequency, new heart failure episodes occurred. Exercise doppler echocardiography showed that the mechanism of this mitral regurgitation was a two leaflet mitral tenting. We discuss here the different mechanisms that could induce these kinds of mitral regurgitation with excessive tenting. We emphasize the interest of early detection by exercise doppler echocardiography even when a triggering factor like atrial fibrillation seems to be involved. We also discuss the interest of mitral valve replacement for these patients.

  13. Increased left ventricular ejection fraction after a meal: potential source of error in performance of radionuclide angiography

    SciTech Connect

    Brown, J.M.; White, C.J.; Sobol, S.M.; Lull, R.J.

    1983-06-01

    The effect of a standardized meal on left ventricular (LV) ejection fraction (EF) was determined by equilibrium radionuclide angiography in 16 patients with stable congestive heart failure but without pulmonary or valvular heart disease. LVEF was determined in the fasting state and 15, 30, and 45 minutes after a meal. Patients with moderately depressed fasting LVEF (30 to 50%), Group I, had a mean increase of 6.9 +/- 2.9% (p less than 0.005) in the LVEF at 45 minutes after the meal. Patients with severely depressed fasting LVEF (less than 30%), Group II, had no change after the meal. It is concluded that significant increases in LVEF may occur after meals in patients with moderate but not severe left ventricular dysfunction. Equilibrium radionuclide angiography studies that are not standardized for patients' mealtimes may introduce an important unmeasured variable that will affect the validity of data in serial studies of left ventricular function.

  14. New strategies for heart failure with preserved ejection fraction: the importance of targeted therapies for heart failure phenotypes

    PubMed Central

    Senni, Michele; Paulus, Walter J.; Gavazzi, Antonello; Fraser, Alan G.; Díez, Javier; Solomon, Scott D.; Smiseth, Otto A.; Guazzi, Marco; Lam, Carolyn S. P.; Maggioni, Aldo P.; Tschöpe, Carsten; Metra, Marco; Hummel, Scott L.; Edelmann, Frank; Ambrosio, Giuseppe; Stewart Coats, Andrew J.; Filippatos, Gerasimos S.; Gheorghiade, Mihai; Anker, Stefan D.; Levy, Daniel; Pfeffer, Marc A.; Stough, Wendy Gattis; Pieske, Burkert M.

    2014-01-01

    The management of heart failure with reduced ejection fraction (HF-REF) has improved significantly over the last two decades. In contrast, little or no progress has been made in identifying evidence-based, effective treatments for heart failure with preserved ejection fraction (HF-PEF). Despite the high prevalence, mortality, and cost of HF-PEF, large phase III international clinical trials investigating interventions to improve outcomes in HF-PEF have yielded disappointing results. Therefore, treatment of HF-PEF remains largely empiric, and almost no acknowledged standards exist. There is no single explanation for the negative results of past HF-PEF trials. Potential contributors include an incomplete understanding of HF-PEF pathophysiology, the heterogeneity of the patient population, inadequate diagnostic criteria, recruitment of patients without true heart failure or at early stages of the syndrome, poor matching of therapeutic mechanisms and primary pathophysiological processes, suboptimal study designs, or inadequate statistical power. Many novel agents are in various stages of research and development for potential use in patients with HF-PEF. To maximize the likelihood of identifying effective therapeutics for HF-PEF, lessons learned from the past decade of research should be applied to the design, conduct, and interpretation of future trials. This paper represents a synthesis of a workshop held in Bergamo, Italy, and it examines new and emerging therapies in the context of specific, targeted HF-PEF phenotypes where positive clinical benefit may be detected in clinical trials. Specific considerations related to patient and endpoint selection for future clinical trials design are also discussed. PMID:25104786

  15. Computer-based assessment of right ventricular regional ejection fraction in patients with repaired Tetralogy of Fallot

    NASA Astrophysics Data System (ADS)

    Teo, S.-K.; Wong, S. T.; Tan, M. L.; Su, Y.; Zhong, L.; Tan, Ru-San

    2015-03-01

    After surgical repair for Tetralogy of Fallot (TOF), most patients experience long-term complications as the right ventricle (RV) undergoes progressive remodeling that eventually affect heart functions. Thus, post-repair surgery is required to prevent further deterioration of RV functions that may result in malignant ventricular arrhythmias and mortality. The timing of such post-repair surgery therefore depends crucially on the quantitative assessment of the RV functions. Current clinical indices for such functional assessment measure global properties such as RV volumes and ejection fraction. However, these indices are less than ideal as regional variations and anomalies are obscured. Therefore, we sought to (i) develop a quantitative method to assess RV regional function using regional ejection fraction (REF) based on a 13-segment model, and (ii) evaluate the effectiveness of REF in discriminating 6 repaired TOF patients and 6 normal control based on cardiac magnetic resonance (CMR) imaging. We observed that the REF for the individual segments in the patient group is significantly lower compared to the control group (P < 0.05 using a 2-tail student t-test). In addition, we also observed that the aggregated REF at the basal, mid-cavity and apical regions for the patient group is significantly lower compared to the control group (P < 0.001 using a 2-tail student t-test). The results suggest that REF could potentially be used as a quantitative index for assessing RV regional functions. The computational time per data set is approximately 60 seconds, which demonstrates our method's clinical potential as a real-time cardiac assessment tool.

  16. Heterogeneous responses of systolic and diastolic left ventricular function to exercise in patients with heart failure and preserved ejection fraction

    PubMed Central

    Sinning, David; Lober, Jil; Post, Heiner; Fraser, Alan G.; Pieske, Burkert; Burkhoff, Daniel; Tschöpe, Carsten

    2015-01-01

    Abstract Aims This study aimed to evaluate ventricular diastolic properties using three‐dimensional echocardiography and tissue Doppler imaging at rest and during exercise in heart failure with preserved ejection fraction (HFpEF) patients with borderline evidence of diastolic dysfunction at rest. Methods and results Results obtained from 52 HFpEF patients (left ventricular ejection fraction ≥ 50%) identified on the basis of heart failure symptoms and E/E′ values between 8 and 15 were compared with those obtained in 26 control patients with no evidence of cardiovascular disease. Mitral flow patterns, tissue Doppler imaging, and volume analysis obtained by three‐dimensional echocardiography were performed at rest and during bicycle exercise. Diastolic compliance was indexed by the E/E′ ratio and left ventricular end‐diastolic volume [(E/E′)/EDV]. There were no significant differences in end‐diastolic volume (EDV), stroke volume (SV), or ejection fraction at rest between groups. In 27 of the 52 patients, E/E′ increased during exercise (11.2 ± 3.7 to 16.8 ± 10.5), driven by a failure to augment early diastole (E′). This correlated with a fall in SV and was associated with an increase in the diastolic index (E/E′)/EDV as a measure for LV stiffness (0.122 ± 0.038 to 0.217 ± 0.14/mL), indicating that impaired diastolic reserve (designated PEF‐IDR) contributed to exercise intolerance. Of the 52 patients, 25 showed no changes in E/E′ during exercise associated with a significant rise in SV and cardiac output, still inappropriate compared with controls. Despite disturbed early diastole (E′), a blunted increase in estimated systolic LV elastance indicated that impaired systolic reserve and chronotropic incompetence rather than primarily diastolic disturbances contributed to exercise intolerance in this group (designated PEF). Conclusion Three‐dimensional stress echocardiography may allow non‐invasive analysis of changes

  17. A Multiphysics Modeling Approach to Develop Right Ventricle Pulmonary Valve Replacement Surgical Procedures with a Contracting Band to Improve Ventricle Ejection Fraction

    PubMed Central

    Tang, Dalin; Yang, Chun; Geva, Tal; Rathod, Rahul; Yamauchi, Haruo; Gooty, Vasu; Tang, Alexander; Kural, Mehmet H.; Billiar, Kristen L.; Gaudette, Glenn; del Nido, Pedro J.

    2012-01-01

    Patients with repaired tetralogy of Fallot account for the majority of cases with late onset right ventricle (RV) failure. A new surgical procedure placing an elastic band in the right ventricle is proposed to improve RV function measured by ejection fraction. A multiphysics modeling approach is developed to combine cardiac magnetic resonance imaging, modeling, tissue engineering and mechanical testing to demonstrate feasibility of the new surgical procedure. Our modeling results indicated that the new surgical procedure has the potential to improve right ventricle ejection fraction by 2–7% which compared favorably with recently published drug trials to treat LV heart failure. PMID:23667272

  18. Peak oxygen uptake and left ventricular ejection fraction, but not depressive symptoms, are associated with cognitive impairment in patients with chronic heart failure

    PubMed Central

    Steinberg, Gerrit; Lossnitzer, Nicole; Schellberg, Dieter; Mueller-Tasch, Thomas; Krueger, Carsten; Haass, Markus; Ladwig, Karl Heinz; Herzog, Wolfgang; Juenger, Jana

    2011-01-01

    Background The aim of the present study was to assess cognitive impairment in patients with chronic heart failure (CHF) and its associations with depressive symptoms and somatic indicators of illness severity, which is a matter of controversy. Methods and results Fifty-five patients with CHF (mean age 55.3 ± 7.8 years; 80% male; New York Heart Association functional class I–III) underwent assessment with an expanded neuropsychological test battery (eg, memory, complex attention, mental flexibility, psychomotor speed) to evaluate objective and subjective cognitive impairment. Depressive symptoms were assessed using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (SCID) and a self-report inventory (Hospital Anxiety and Depression Scale [HADS]). A comprehensive clinical dataset, including left ventricular ejection fraction, peak oxygen uptake, and a 6-minute walk test, was obtained for all patients. Neuropsychological functioning revealed impairment in 56% of patients in at least one measure of our neuropsychological test battery. However, the Mini Mental State Examination (MMSE) could only detect cognitive impairment in 1.8% of all patients, 24% had HADS scores indicating depressive symptoms, and 11.1% met SCID criteria for a depressive disorder. No significant association was found between depressive symptoms and cognitive impairment. Left ventricular ejection fraction was related to subjective cognitive impairment, and peak oxygen uptake was related to objective cognitive impairment. Conclusion Cognitive functioning was substantially reduced in patients with CHF and should therefore be diagnosed and treated in routine clinical practice. Caution is advised when the MMSE is used to identify cognitive impairment in patients with CHF. PMID:22267941

  19. The Prognostic Value of the Left Ventricular Ejection Fraction Is Dependent upon the Severity of Mitral Regurgitation in Patients with Acute Myocardial Infarction

    PubMed Central

    Cho, Jung Sun; Youn, Ho-Joong; Her, Sung-Ho; Park, Maen Won; Kim, Chan Joon; Park, Gyung-Min; Cho, Jae Yeong; Ahn, Youngkeun; Kim, Kye Hun; Park, Jong Chun; Seung, Ki Bae; Cho, Myeong Chan; Kim, Chong Jin; Kim, Young Jo; Han, Kyoo Rok; Kim, Hyo Soo

    2015-01-01

    The prognostic value of the left ventricle ejection fraction (LVEF) after acute myocardial infarction (AMI) has been questioned even though it is an accurate marker of left ventricle (LV) systolic dysfunction. This study aimed to examine the prognostic impact of LVEF in patients with AMI with or without high-grade mitral regurgitation (MR). A total of 15,097 patients with AMI who received echocardiography were registered in the Korean Acute Myocardial Infarction Registry (KAMIR) between January 2005 and July 2011. Patients with low-grade MR (grades 0-2) and high-grade MR (grades 3-4) were divided into the following two sub-groups according to LVEF: LVEF ≤ 40% (n = 2,422 and 197, respectively) and LVEF > 40% (n = 12,252 and 226, respectively). The primary endpoints were major adverse cardiac events (MACE), cardiac death, and all-cause death during the first year after registration. Independent predictors of mortality in the multivariate analysis in AMI patients with low-grade MR were age ≥ 75 yr, Killip class ≥ III, N-terminal pro-B-type natriuretic peptide > 4,000 pg/mL, high-sensitivity C-reactive protein ≥ 2.59 mg/L, LVEF ≤ 40%, estimated glomerular filtration rate (eGFR), and percutaneous coronary intervention (PCI). However, PCI was an independent predictor in AMI patients with high-grade MR. No differences in primary endpoints between AMI patients with high-grade MR (grades 3-4) and EF ≤ 40% or EF > 40% were noted. MR is a predictor of a poor outcome regardless of ejection fraction. LVEF is an inadequate method to evaluate contractile function of the ischemic heart in the face of significant MR. PMID:26130953

  20. The Prognostic Value of the Left Ventricular Ejection Fraction Is Dependent upon the Severity of Mitral Regurgitation in Patients with Acute Myocardial Infarction.

    PubMed

    Cho, Jung Sun; Youn, Ho-Joong; Her, Sung-Ho; Park, Maen Won; Kim, Chan Joon; Park, Gyung-Min; Jeong, Myung Ho; Cho, Jae Yeong; Ahn, Youngkeun; Kim, Kye Hun; Park, Jong Chun; Seung, Ki Bae; Cho, Myeong Chan; Kim, Chong Jin; Kim, Young Jo; Han, Kyoo Rok; Kim, Hyo Soo

    2015-07-01

    The prognostic value of the left ventricle ejection fraction (LVEF) after acute myocardial infarction (AMI) has been questioned even though it is an accurate marker of left ventricle (LV) systolic dysfunction. This study aimed to examine the prognostic impact of LVEF in patients with AMI with or without high-grade mitral regurgitation (MR). A total of 15,097 patients with AMI who received echocardiography were registered in the Korean Acute Myocardial Infarction Registry (KAMIR) between January 2005 and July 2011. Patients with low-grade MR (grades 0-2) and high-grade MR (grades 3-4) were divided into the following two sub-groups according to LVEF: LVEF ≤ 40% (n = 2,422 and 197, respectively) and LVEF > 40% (n = 12,252 and 226, respectively). The primary endpoints were major adverse cardiac events (MACE), cardiac death, and all-cause death during the first year after registration. Independent predictors of mortality in the multivariate analysis in AMI patients with low-grade MR were age ≥ 75 yr, Killip class ≥ III, N-terminal pro-B-type natriuretic peptide > 4,000 pg/mL, high-sensitivity C-reactive protein ≥ 2.59 mg/L, LVEF ≤ 40%, estimated glomerular filtration rate (eGFR), and percutaneous coronary intervention (PCI). However, PCI was an independent predictor in AMI patients with high-grade MR. No differences in primary endpoints between AMI patients with high-grade MR (grades 3-4) and EF ≤ 40% or EF > 40% were noted. MR is a predictor of a poor outcome regardless of ejection fraction. LVEF is an inadequate method to evaluate contractile function of the ischemic heart in the face of significant MR.

  1. Evaluation of biventricular ejection fraction with ECG-gated 16-slice CT: preliminary findings in acute pulmonary embolism in comparison with radionuclide ventriculography.

    PubMed

    Coche, Emmanuel; Vlassenbroek, Alain; Roelants, Véronique; D'Hoore, William; Verschuren, Franck; Goncette, Louis; Maldague, Baudouin

    2005-07-01

    This study aimed to assess the feasibility of cardiac global function evaluation during a whole-chest multi-slice CT (MSCT) acquisition in patients referred for suspicion of pulmonary embolism (PE), and to compare the results with planar equilibrium radionuclide ventriculography (ERNA). Ten consecutive haemodynamically stable patients (six female, four male; mean age 69.7 years; heart rate 65-99 bpm) with suspicion of PE underwent an MSCT and ERNA within a 6 h period. CT acquisition was performed after contrast medium injection by using 16x1.5 mm collimation and retrospective ECG gating. Left ventricular (LVEF) and right ventricular (RVEF) ejection fractions were calculated using dedicated three-dimensional software. Relationships between measurements obtained with MSCT and ERNA were assessed using linear regression analysis and reliability of MSCT was assessed with intra-class correlation coefficient. Bland-Altman analysis was performed to calculate limits of agreement between MSCT and ERNA. MSCT was performed successfully in ten patients with a mean acquisition time of 16.5+/-2.8 s. Functional cardiac evaluation was possible on CT for all patients except for one due to poor opacification of right ventricle. Linear regression analysis showed a good correlation between MSCT and ERNA for the LVEF (R=0.91) and the RVEF (R=0.89) measurements. Intra-class correlation was superior for LVEF (0.92) than for the RVEF (0.68). Bland-Altman plots demonstrated that MSCT substantially overestimated the ERNA RVEF. Morphological CT data demonstrated PE in four of ten of patients and alternative diagnoses in five of ten patients. Our study reveals that MSCT with retrospective ECG gating may provide in one modality a morphological and a functional cardiopulmonary evaluation. Comparison with ERNA demonstrated a good correlation for both ventricular ejection fractions.

  2. Effect of Phosphodiesterase-5 Inhibition on Exercise Capacity and Clinical Status in Heart Failure with Preserved Ejection Fraction: A Randomized Clinical Trial

    PubMed Central

    Redfield, Margaret M; Chen, Horng H; Borlaug, Barry A; Semigran, Marc J.; Lee, Kerry L.; Lewis, Gregory; LeWinter, Martin M.; Rouleau, Jean L.; Bull, David A.; Mann, Douglas L.; Deswal, Anita; Stevenson, Lynne W.; Givertz, Michael M.; Ofili, Elizabeth O.; O’Connor, Christopher M.; Felker, G. Michael; Goldsmith, Steven R.; Bart, Bradley A.; McNulty, Steven E; Ibarra, Jenny C.; Lin, Grace; Oh, Jae K.; Patel, Manesh R.; Kim, Raymond J.; Tracy, Russell P.; Velazquez, Eric J.; Anstrom, Kevin J.; Hernandez, Adrian F.; Mascette, Alice M.; Braunwald, Eugene

    2013-01-01

    Importance Studies in experimental and human heart failure suggest that phosphodiesterase type-5 inhibitors may enhance cardiovascular function, and thus, exercise capacity in heart failure with preserved ejection fraction. Objective To determine the effect of the phosphodiesterase type-5 inhibitor, sildenafil, in comparison to placebo on exercise capacity and clinical status in heart failure with preserved ejection fraction. Design, setting, and patients Multicenter, double-blind, placebo-controlled, parallel design, randomized clinical trial of 216 stable outpatients with heart failure, ejection fraction ≥ 50%, elevated N-terminal pro-brain natriuretic peptide or elevated invasively-measured filling pressures, and reduced exercise capacity. Participants were randomized from October 2008 through February 2012 at 26 centers in the United States and Canada. Intervention Sildenafil (n=113) or placebo (n=103) administered orally at 20 mg three times daily for 12 weeks followed by 60 mg three times daily for 12 weeks. Main outcome measures Primary endpoint was change in peak oxygen consumption after 24 weeks of therapy. Secondary endpoints included change in six-minute walk distance and a three tier hierarchical composite clinical status score where patients were ranked (range 1-N) based on time to death, time to cardiovascular or cardiorenal hospitalization and change in quality of life for participants alive without cardiovascular or cardiorenal hospitalization at 24 weeks. Results Median age was 69 years and 48% of patients were female. At baseline, median peak oxygen consumption (11.7 ml/kg/min) and six-minute walk distance (308 meters) were reduced and median E/e′ (16), left atrial volume index (44 ml/m2) and pulmonary artery systolic pressure (41 mmHg) were consistent with chronically-elevated left ventricular filling pressures. At 24 weeks, median (interquartile range) changes in peak oxygen consumption (ml/kg/min) in patients who received placebo [−0

  3. Comparison of left ventricular ejection fraction values obtained using invasive contrast left ventriculography, two-dimensional echocardiography, and gated single-photon emission computed tomography

    PubMed Central

    Garg, Nadish; Dresser, Thomas; Aggarwal, Kul; Gupta, Vishal; Mittal, Mayank K; Alpert, Martin A

    2016-01-01

    Objectives: Left ventricular ejection fraction can be measured by a variety of invasive and non-invasive cardiac techniques. This study assesses the relation of three diagnostic modalities to each other in the measurement of left ventricular ejection fraction: invasive contrast left ventriculography, two-dimensional echocardiography, and quantitative gated single-photon emission computed tomography. Methods: Retrospective chart review was conducted on 58 patients hospitalized with chest pain, who underwent left ventricular ejection fraction evaluation using each of the aforementioned modalities within a 3-month period not interrupted by myocardial infarction or revascularization. Results: The mean left ventricular ejection fraction values were as follows: invasive contrast left ventriculography (0.44±0.15), two-dimensional echocardiography (0.46±0.13), and gated single-photon emission computed tomography (0.37±0.10). Correlations coefficients and associated p values were as follows: invasive contrast left ventriculography versus two-dimensional echocardiography (r=0.69, p<0.001), invasive contrast left ventriculography versus gated single-photon emission computed tomography (r=0.80, p<0.0001), and gated single-photon emission computed tomography versus two-dimensional echocardiography (r=0.69, p<0.001). Conclusion: Our results indicate that strong positive correlations exist among the three techniques studied. PMID:27621804

  4. Copeptin in patients with heart failure and preserved ejection fraction: a report from the prospective KaRen-study

    PubMed Central

    Hage, Camilla; Lund, Lars H; Donal, Erwan; Daubert, Jean-Claude; Linde, Cecilia; Mellbin, Linda

    2015-01-01

    Introduction Underlying mechanisms of heart failure (HF) with preserved ejection fraction (HFPEF) remain unknown. We explored copeptin, a biomarker of the arginine vasopressin system, hypothesising that copeptin in HFPEF is elevated, associated with diastolic dysfunction and N-terminal pro-brain natriuretic peptide (NT-proBNP) and predictive of HF hospitalisation and mortality. Methods and analysis In a prospective observational substudy of the The Karolinska Rennes (KaRen) 86 patients with symptoms of acute HF and ejection fraction (EF) ≥45% were enrolled. After 4–8 weeks, blood sampling and echocardiography was performed. Plasma-copeptin was analysed in 86 patients and 62 healthy controls. Patients were followed in median 579 days (quartile 1; quartile 3 (Q1;Q3) 276;1178) regarding the composite end point all-cause mortality or HF hospitalisation. Ethics and dissemination The patients with HFPEF had higher copeptin levels, median 13.56 pmol/L (Q1;Q3 8.56;20.55) than controls 5.98 pmol/L (4.15;9.42; p<0.001). Diastolic dysfunction, assessable in 75/86 patients, was present in 45 and absent in 30 patients. Copeptin did not differ regarding diastolic dysfunction and did not correlate with cardiac function but with NT-proBNP (r=0.223; p value=0.040). In univariate Cox regression analysis log copeptin predicted the composite end point (HR 1.56 (95% CI 1.03 to 2.38; p value=0.037)) but not after adjusting for NT-proBNP (HR 1.39 (95% CI 0.91 to 2.12; p value=0.125)). Conclusions In the present patients with HFPEF, copeptin is elevated, correlates with NT-proBNP but not markers of diastolic dysfunction, and has prognostic implications, however blunted after adjustment for NT-proBNP. The HFPEF pathophysiology may be better reflected by markers of neurohormonal activation than by diastolic dysfunction. Trial registration number ClinicalTrials.gov NCT00774709. PMID:26568833

  5. Short-Term Effects of Ketamine and Isoflurane on Left Ventricular Ejection Fraction in an Experimental Swine Model

    PubMed Central

    Wessler, Benjamin; Madias, Christopher; Pandian, Natesa; Link, Mark S.

    2011-01-01

    Background. General anesthesia is an essential element of experimental medical procedures. Ketamine and isoflurane are agents commonly used to induce and maintain anesthesia in animals. The cardiovascular effects of these anesthetic agents are diverse, and the response of global myocardial function is unknown. Methods. In a series of 15 swine, echocardiography measurements of left ventricular ejection fraction (LVEF) were obtained before the animals received anesthesia (baseline), after an intramuscular injection of ketamine (postketamine) and after inhaled isoflurane (postisoflurane). Results. The mean LVEF of an unanesthetized swine was 47 ± 3%. There was a significant decrease in the mean LVEF after administration of ketamine to 41 + 6.5% (P = 0.003). The addition of inhaled isoflurane did not result in further decrease in mean LVEF (mean LVEF 38 ± 7.2%, P = 0.22). Eight of the swine had an increase in their LVEF with sympathetic stimulation. Conclusions. In our experimental model the administration of ketamine was associated with decreased LV function. The decrease may be largely secondary to a blunting of sympathetic tone. The addition of isoflurane to ketamine did not significantly change LV function. A significant number of animals had returned to preanesthesia LV function with sympathetic stimulation. PMID:22347646

  6. Risk of ventricular arrhythmia in patients with myocardial infarction and non-obstructive coronary arteries and normal ejection fraction

    PubMed Central

    Bière, Loïc; Niro, Marjorie; Pouliquen, Hervé; Gourraud, Jean-Baptiste; Prunier, Fabrice; Furber, Alain; Probst, Vincent

    2017-01-01

    AIM To assess the arrhythmic determinants and prognosis of patients presenting with myocardial infarction and non-obstructive coronary arteries (MINOCA) with normal ejection fraction (EF). METHODS This is an observational analysis of 131 MINOCA patients with normal EF. Three cardiac magnetic resonance (CMR) diagnosis classes were recognized according to the late gadolinium enhancement (LGE) pattern: Myocardial infarction (MI) (n = 34), myocarditis (n = 47), and “no LGE” (n = 50). Ventricular events occurring during hospitalization were recorded and the entire population was followed-up at 1 year. RESULTS Ventricular arrhythmia was observed in 18 (13.8%) patients during hospitalization. The “no LGE” patients experienced fewer ventricular events than the MI and myocarditis patients [4.0% vs 26.5% and 14.9%, respectively (P = 0.013)]. There was no significant difference between the MI and myocarditis groups. On multivariate analysis, LGE transmural extent [OR = 1.52 (1.08-2.15), P = 0.017] and ST-segment elevation [OR = 4.65 (1.61-13.40), P = 0.004] were independent predictors of ventricular arrhythmic events, irrespective of the diagnosis class. Finally, no patient experienced sudden cardiac death or ventricular arrhythmia recurrence at 1-year. CONCLUSION MINOCA patients with normal EF presented no 1-year cardiovascular events, irrespective of the CMR diagnosis class. LGE transmural extent and ST segment elevation at admission are risk markers of ventricular arrhythmia during hospitalization.

  7. Phenomapping for the Identification of Hypertensive Patients with the Myocardial Substrate for Heart Failure with Preserved Ejection Fraction.

    PubMed

    Katz, Daniel H; Deo, Rahul C; Aguilar, Frank G; Selvaraj, Senthil; Martinez, Eva E; Beussink-Nelson, Lauren; Kim, Kwang-Youn A; Peng, Jie; Irvin, Marguerite R; Tiwari, Hemant; Rao, D C; Arnett, Donna K; Shah, Sanjiv J

    2017-03-03

    We sought to evaluate whether unbiased machine learning of dense phenotypic data ("phenomapping") could identify distinct hypertension subgroups that are associated with the myocardial substrate (i.e., abnormal cardiac mechanics) for heart failure with preserved ejection fraction (HFpEF). In the HyperGEN study, a population- and family-based study of hypertension, we studied 1273 hypertensive patients utilizing clinical, laboratory, and conventional echocardiographic phenotyping of the study participants. We used machine learning analysis of 47 continuous phenotypic variables to identify mutually exclusive groups constituting a novel classification of hypertension. The phenomapping analysis classified study participants into 2 distinct groups that differed markedly in clinical characteristics, cardiac structure/function, and indices of cardiac mechanics (e.g., phenogroup #2 had a decreased absolute longitudinal strain [12.8 ± 4.1 vs. 14.6 ± 3.5%] even after adjustment for traditional comorbidities [p < 0.001]). The 2 hypertension phenogroups may represent distinct subtypes that may benefit from targeted therapies for the prevention of HFpEF.

  8. Determination of left ventricular ejection fraction by visual estimation during real-time two-dimensional echocardiography

    SciTech Connect

    Rich, S.; Sheikh, A.; Gallastegui, J.; Kondos, G.T.; Mason, T.; Lam, W.

    1982-09-01

    It has been shown that the measured reduction in the cross-sectional area of the left ventricle (LV), as viewed in the short axis, closely approximates its ejection fraction (EF). We assessed the reliability of using two-dimensional echocardiography (2DE) to visually estimate the EF during real-time viewing, without the need of digitizers, planimetry, or calculations. Twenty-five adult hospitalized patients with either suspected or known cardiac disease were evaluated prospectively. Each patient also had gated nuclear angiography during the same admission, and 14 had cardiac catheterization with left ventriculography. The EF was determined by 2DE using a visual estimate of the percent area reduction of the LV cavity in the short-axis view at the level of the papillary muscles. All 2 DE studies were read by two or more blinded reviewers, with a value for the EF to the nearest 2.5% determined by consensus. These values correlated closely to the values determined in all 25 patients with gated nuclear angiography (r . 0.927) and the 14 patients who had left ventriculography (r . 0.935). We believe that this method of visually estimating the LVEF will enable echocardiographers to easily use 2 DE for a reliable and instantaneous assessment of ventricular function, without the need of sophisticated analytical equipment.

  9. Effects of renal denervation on vascular remodelling in patients with heart failure and preserved ejection fraction: A randomised control trial

    PubMed Central

    Hayward, Carl; Keegan, Jennifer; Gatehouse, Peter D; Rajani, Ronak; Khattar, Rajdeep S; Mohiaddin, Raad H; Rosen, Stuart D; Lyon, Alexander R; di Mario, Carlo

    2017-01-01

    Objective To assess the effect of renal denervation (RDT) on micro- and macro-vascular function in patients with heart failure with preserved ejection fraction (HFpEF). Design A prospective, randomised, open-controlled trial with blinded end-point analysis. Setting A single-centre London teaching hospital. Participants Twenty-five patients with HFpEF who were recruited into the RDT-PEF trial. Main outcome measures Macro-vascular: 24-h ambulatory pulse pressure, aorta distensibilty (from cardiac magnetic resonance imaging (CMR), aorta pulse wave velocity (CMR), augmentation index (peripheral tonometry) and renal artery blood flow indices (renal MR). Micro-vascular: endothelial function (peripheral tonometry) and urine microalbuminuria. Results At baseline, 15 patients were normotensive, 9 were hypertensive and 1 was hypotensive. RDT did not lower any of the blood pressure indices. Though there was evidence of abnormal vascular function at rest, RDT did not affect these at 3 or 12 months follow-up. Conclusions RDT did not improve markers of macro- and micro-vascular function. PMID:28228942

  10. Diagnostic and Prognostic Value of CMR T1-Mapping in Patients With Heart Failure and Preserved Ejection Fraction.

    PubMed

    Rommel, Karl-Philipp; Lücke, Christian; Lurz, Philipp

    2017-03-14

    Heart failure with preserved ejection fraction (HFpEF) presents a major challenge in modern cardiology. Although this syndrome is of increasing prevalence and is associated with unfavorable outcomes, treatment trials have failed to establish effective therapies. Currently, solutions to this dilemma are being investigated, including categorizing and characterizing patients more diversely to individualize treatment. In this regard, new imaging techniques might provide important information. Diastolic dysfunction is a diagnostic and pathophysiological cornerstone in HFpEF and is believed to be caused by systemic inflammation with the development of interstitial myocardial fibrosis and myocardial stiffening. Cardiac magnetic resonance (CMR) T1-mapping is a novel tool, which allows noninvasive quantification of the extracellular space and diffuse myocardial fibrosis. This review provides an overview of the potential of myocardial tissue characterization with CMR T1 mapping in HFpEF patients, outlining its diagnostic and prognostic implications and discussing future directions. We conclude that CMR T1 mapping is potentially an effective tool for patient characterization in large-scale epidemiological, diagnostic, and therapeutic HFpEF trials beyond traditional imaging parameters.

  11. Correlation of right ventricular ejection fraction and tricuspid annular plane systolic excursion in tetralogy of Fallot by magnetic resonance imaging.

    PubMed

    Morcos, Peter; Vick, G Wesley; Sahn, David J; Jerosch-Herold, Michael; Shurman, Alan; Sheehan, Florence H

    2009-03-01

    The correlation between right ventricular ejection fraction (RVEF) and tricuspid annular plane systolic excursion (TAPSE) by two-dimensional (2-D) echo has been repeatedly validated, but not by magnetic resonance imaging (MRI) nor in patients with congenital heart disease. We tested whether TAPSE measurements by MRI correlate with RVEF in surgically repaired tetralogy of Fallot (TOF) patients. TAPSE was measured from systolic displacement of the RV-freewall/tricuspid annular plane junction in the apical 4-chamber view in 7 normal subjects and 14 TOF patients. The RV was reconstructed in 3-D from manually traced borders on MR images to compute true EF. Because we previously observed discrepancy between TAPSE and RVEF in the presence of regional dysfunction, we also analyzed RV wall motion in terms of regional stroke volume at 20 short axis slices from apex to tricuspid annulus. RVEF was 52 +/- 3% in normal subjects and 41 +/- 9% in TOF (P < 0.01). TAPSE correlated weakly (r = 0.50, P < 0.05) with RVEF. TOF patients exhibited increased regional stroke volume from apical portions of the RV and decreased regional stroke volume at the base compared to normal (P < 0.05 at 15 of 20 slices). Regional stroke volume in apical slices correlated inversely with RVEF such that patients with higher apical stroke volume had lower RVEF (P < 0.05). TAPSE is not a reliable measure of RVEF in TOF by MRI. TAPSE may be of limited use in conditions that exhibit abnormal regional contraction.

  12. Increased Left Ventricular Stiffness Impairs Exercise Capacity in Patients with Heart Failure Symptoms Despite Normal Left Ventricular Ejection Fraction

    PubMed Central

    Sinning, David; Kasner, Mario; Westermann, Dirk; Schulze, Karsten; Schultheiss, Heinz-Peter; Tschöpe, Carsten

    2011-01-01

    Aims. Several mechanisms can be involved in the development of exercise intolerance in patients with heart failure despite normal left ventricular ejection fraction (HFNEF) and may include impairment of left ventricular (LV) stiffness. We therefore investigated the influence of LV stiffness, determined by pressure-volume loop analysis obtained by conductance catheterization, on exercise capacity in HFNEF. Methods and Results. 27 HFNEF patients who showed LV diastolic dysfunction in pressure-volume (PV) loop analysis performed symptom-limited cardiopulmonary exercise testing (CPET) and were compared with 12 patients who did not show diastolic dysfunction in PV loop analysis. HFNEF patients revealed a lower peak performance (P = .046), breathing reserve (P = .006), and ventilation equivalent for carbon dioxide production at rest (P = .002). LV stiffness correlated with peak oxygen uptake (r = −0.636, P < .001), peak oxygen uptake at ventilatory threshold (r = −0.500, P = .009), and ventilation equivalent for carbon dioxide production at ventilatory threshold (r = 0.529, P = .005). Conclusions. CPET parameters such as peak oxygen uptake, peak oxygen uptake at ventilatory threshold, and ventilation equivalent for carbon dioxide production at ventilatory threshold correlate with LV stiffness. Increased LV stiffness impairs exercise capacity in HFNEF. PMID:21403885

  13. Right Ventricular Function in Heart Failure with Preserved Ejection Fraction: A Community Based Study

    PubMed Central

    Mohammed, Selma F.; Hussain, Imad; Ezzeddine, Omar F. Abou; Takahama, Hiroyuki; Kwon, Susan H.; Forfia, Paul; Roger, Véronique L.; Redfield, Margaret M.

    2014-01-01

    Background: The prevalence and clinical significance of right ventricular (RV) systolic dysfunction (RVD) in patients with heart failure and preserved EF (HFpEF) are not well characterized. Methods and Results: Consecutive, prospectively identified HFpEF (Framingham HF criteria, EF ≥50%) patients (N=562) from Olmsted County, Minnesota underwent echocardiography at HF diagnosis and follow-up for cause specific mortality and HF hospitalization. RV function was categorized by tertiles of tricuspid annular plane systolic excursion (TAPSE) and by semi-quantitative (normal, mild RVD or moderate-severe RVD) 2D assessment. Whether RVD was defined by semi-quantitative assessment or TAPSE ≤ 15 mm, HFpEF patients with RVD were more likely to have atrial fibrillation, pacemakers and chronic diuretic therapy. At echo, patients with RVD had slightly lower LVEF, worse diastolic dysfunction, lower blood pressure and cardiac output, higher pulmonary artery systolic pressure (PASP), and more severe RV enlargement and tricuspid valve regurgitation. Adjusting for age, sex, PASP and comorbidities, the presence of any RVD by semi-quantitative assessment was associated with higher all-cause (hazard ratio (HR) = 1.35 (1.03-1.77; p=0.03)) and cardiovascular (HR=1.85 (1.20-2.80; p=0.006)) mortality and higher first (HR=1.99 (1.35-2.90; p=0.0006) and multiple (HR=1.81 (1.18-2.78; p=0.007) HF hospitalization rates. RVD defined by TAPSE values showed similar but weaker associations with mortality and HF hospitalizations. Conclusions: In the community, RVD is common in HFpEF patients, associated with clinical and echocardiographic evidence of more advanced HF and predictive of poorer outcomes. PMID:25391518

  14. Impact of Race, Ethnicity, and Multimodality Biomarkers on the Incidence of New-Onset Heart Failure With Preserved Ejection Fraction (from the Multi-Ethnic Study of Atherosclerosis).

    PubMed

    Silverman, Michael G; Patel, Birju; Blankstein, Ron; Lima, Joao A C; Blumenthal, Roger S; Nasir, Khurram; Blaha, Michael J

    2016-05-01

    Heart failure with preserved ejection fraction (HFpEF) is a prevalent condition with no established prevention or treatment strategies. Furthermore, the pathophysiology and predisposing risk factors for HFpEF are incompletely understood. Therefore, we sought to characterize the incidence and determinants of HFpEF in the Multi-Ethnic Study of Atherosclerosis (MESA). Our study included 6,781 MESA participants (White, Black, Chinese, and Hispanic men and women age 45 to 84 years, free of baseline cardiovascular disease). The primary end point was time to diagnosis of HFpEF (left ventricular ejection fraction ≥45%). Multivariable adjusted hazard ratios (HRs) with 95% confidence intervals were calculated to identify predictors of HFpEF. Over median follow-up of 11.2 years (10.6 to 11.7), 111 subjects developed HFpEF (cumulative incidence 1.7%). Incidence rates were similar across all races/ethnicities. Age (HR 2.3 [1.7 to 3.0]), hypertension (HR 1.8 [1.1 to 2.9]), diabetes (HR 2.3 [1.5 to 3.7]), body mass index (HR 1.4 [1.1 to 1.7]), left ventricular hypertrophy by electrocardiography (HR 4.3 [1.7 to 11.0]), interim myocardial infarction (HR 4.8 [2.7 to 8.6]), elevated N-terminal of the prohormone brain natriuretic peptide (HR 2.4 [1.5 to 4.0]), detectable troponin T (HR 4.5 [1.9 to 10.9]), and left ventricular mass index by magnetic resonance imaging (MRI; 1.3 [1.0 to 1.6]) were significant predictors of incident HFpEF. Worsening renal function, inflammatory markers, and coronary artery calcium were significant univariate but not multivariate predictors of HFpEF. Gender was neither a univariate nor multivariate predictor of HFpEF. In conclusion, we demonstrate several risk factors and biomarkers associated with incident HFpEF that were consistent across different racial/ethnic groups and may represent potential therapeutic targets for the prevention and treatment of HFpEF.

  15. Synergistic prognostic values of cardiac sympathetic innervation with left ventricular hypertrophy and left atrial size in heart failure patients without reduced left ventricular ejection fraction: a cohort study

    PubMed Central

    Doi, Takahiro; Nakata, Tomoaki; Hashimoto, Akiyoshi; Yuda, Satoshi; Wakabayashi, Takeru; Kouzu, Hidemichi; Kaneko, Naofumi; Hase, Mamoru; Tsuchihashi, Kazufumi; Miura, Tetsuji

    2012-01-01

    Objectives This study tested whether cardiac sympathetic innervation assessed by metaiodobenzylguanidine (MIBG) activity has long-term prognostic value in combination with left ventricular hypertrophy (LVH) and left atrial size in heart failure (HF) patients without reduced left ventricular ejection fraction (LVEF). Design A single-centre prospective cohort study. Setting/participants With primary endpoints of cardiac death and rehospitalisation due to HF progression, 178 consecutive symptomatic HF patients with 74% men, mean age of 56 years and mean LVEF of 64.5% were followed up for 80 months. The entry criteria consisted of LVEF more than 50%, completion of predischarge clinical evaluations including cardiac MIBG and echocardiographic studies and at least more than 1-year follow-up when survived. Results Thirty-four patients with cardiac evens had larger left atrial dimension (LAD), increased LV mass index, reduced MIBG activity quantified as heart-to-mediastinum ratio (HMR) than did the others. Multivariable Cox analysis showed that LAD and HMR were significant predictors (HR of 1.080 (95% CI 1.00 to 1.16, p=0.044) and 0.107 (95% CI 0.01 to 0.61, p=0.012, respectively). Thresholds of HMR (1.65) and LAD (37 mm) were closely related to identification of high-risk patients. In particular, HMR was a significant determinant of cardiac events in both patients with and without LV hypertrophy. Reduced HMR with enlarged LAD or LV hypertrophy identified patients at most increased risk; overall log-rank value, 11.5, p=0.0032 for LAD and 17.5, p=0.0002, respectively. Conclusions In HF patients without reduced LV ejection fraction, impairment of cardiac sympathetic innervation is related to cardiac outcomes independently and synergistically with LA size and LV hypertrophy. Cardiac sympathetic innervation assessment can contribute to better risk-stratification in combination with evaluation of LA size and LV mass but is needed to be evaluated for establishing aetiology

  16. Presence of ´isolated´ tricuspid regurgitation should prompt the suspicion of heart failure with preserved ejection fraction

    PubMed Central

    Mascherbauer, Julia; Kammerlander, Andreas A.; Zotter-Tufaro, Caroline; Aschauer, Stefan; Duca, Franz; Dalos, Daniel; Winkler, Susanne; Schneider, Matthias; Bergler-Klein, Jutta; Bonderman, Diana

    2017-01-01

    Background Diastolic dysfunction of the left ventricle is common but frequently under-diagnosed. Particularly in advanced stages affected patients may present with significant functional tricuspid regurgitation (TR) as the most prominent sign on echocardiography. The underlying left ventricular pathology may eventually be missed and symptoms of heart failure are attributed to TR, with respective therapeutic consequences. The aim of the present study was to determine prevalence and mechanisms underlying TR evolution in heart failure with preserved ejection fraction (HFpEF). Methods and results Consecutive HFpEF patients were enrolled in this prospective, observational study. Confirmatory diagnostic tests including echocardiography and invasive hemodynamic assessments were performed. Of the 175 patients registered between 2010 and 2014, 51% had significant (moderate or severe) TR without structural abnormalities of the tricuspid valve. Significant hemodynamic differences between patients with and without relevant TR were encountered. These included elevated pulmonary vascular resistance (p = 0.038), reduced pulmonary arterial compliance (PAC, p = 0.005), and elevated left ventricular filling pressures (p = 0.039) in the TR group. Multivariable binary logistic regression analysis revealed diastolic pulmonary artery pressure (p = 0.029) and PAC (p = 0.048) as independent determinants of TR. Patients were followed for 18.1±14.1 months, during which 32% had a cardiac event. While TR was associated with outcome in the univariable analysis, it failed to predict event-free survival in the multivariable model. Conclusions The presence of ´isolated´ functional TR should prompt the suspicion of HFpEF. Our data show that significant TR is a marker of advanced HFpEF but neither an isolated entity nor independently associated with event-free survival. PMID:28199339

  17. Acute hemodynamic effects of inhaled sodium nitrite in pulmonary hypertension associated with heart failure with preserved ejection fraction

    PubMed Central

    Simon, Marc A.; Vanderpool, Rebecca R.; Nouraie, Mehdi; Bachman, Timothy N.; White, Pamela M.; Sugahara, Masataka; Gorcsan, John; Parsley, Ed L.; Gladwin, Mark T.

    2016-01-01

    BACKGROUND. Pulmonary hypertension (PH) is associated with poor outcomes, yet specific treatments only exist for a small subset of patients. The most common form of PH is that associated with left heart disease (Group 2), for which there is no approved therapy. Nitrite has shown efficacy in preclinical animal models of Group 1 and 2 PH, as well as in patients with left heart failure with preserved ejection fraction (HFpEF). We evaluated the safety and efficacy of a potentially novel inhaled formulation of nitrite in PH-HFpEF patients as compared with Group 1 and 3 PH. METHODS. Cardiopulmonary hemodynamics were recorded after acute administration of inhaled nitrite at 2 doses, 45 and 90 mg. Safety endpoints included change in systemic blood pressure and methemoglobin levels. Responses were also compared with those administered inhaled nitric oxide. RESULTS. Thirty-six patients were enrolled (10 PH-HFpEF, 20 Group 1 pulmonary arterial hypertension patients on background PH-specific therapy, and 6 Group 3 PH). Drug administration was well tolerated. Nitrite inhalation significantly lowered pulmonary, right atrial, and pulmonary capillary wedge pressures, most pronounced in patients with PH-HFpEF. There was a modest decrease in cardiac output and systemic blood pressure. Pulmonary vascular resistance decreased only in Group 3 PH patients. There was substantial increase in pulmonary artery compliance, most pronounced in patients with PH-HFpEF. CONCLUSIONS. Inhaled nitrite is safe in PH patients and may be efficacious in PH-HFpEF and Group 3 PH primarily via improvements in left and right ventricular filling pressures and pulmonary artery compliance. The lack of change in pulmonary vascular resistance likely may limit efficacy for Group 1 patients. TRIAL REGISTRATION. ClinicalTrials.gov NCT01431313 FUNDING. This work was supported in part by the NIH grants P01HL103455 (to MAS and MTG), R01HL098032 (to MTG), and R01HL096973 (to MTG), and Mast Therapeutics, Inc. PMID

  18. Prognostic value of three-dimensional echocardiographic right ventricular ejection fraction in patients with pulmonary arterial hypertension

    PubMed Central

    Murata, Mitsushige; Tsugu, Toshimitsu; Kawakami, Takashi; Kataoka, Masaharu; Minakata, Yugo; Endo, Jin; Tsuruta, Hikaru; Itabashi, Yuji; Maekawa, Yuichiro; Murata, Mitsuru; Fukuda, Keiichi

    2016-01-01

    Background Right ventricular (RV) function is an independent predictor of clinical outcomes in patients with pulmonary arterial hypertension (PAH). However, it remains controversial which RV parameter should be measured as an appropriate index for the treatment of PAH. The aim of this study was to identify the most useful parameter that correlates with hemodynamics and predicts clinical outcomes in PAH. Results Most of the clinical and echocardiographic RV parameters were significantly correlated with pulmonary vascular resistance (PVR) as well as mean pulmonary arterial pressure (mPAP). Among these, three dimensional right ventricular ejection fraction (3DRVEF) showed the strongest hemodynamic correlation, followed by 6-minute walk distance. Receiver operating characteristic analysis of association with cardiac events including death, hospitalization, and intervention revealed a greater area under the curve for 3DRVEF than for mPAP (0.78 vs. 0.74). Kaplan-Meier analysis showed that patients with 3DRVEF less than 38% had significantly shorter event-free survival than those with greater than 38% (P = 0.0007). Finally, the Cox proportional hazards analysis revealed that 3DRVEF, but not mPAP, was an independent predictor of clinical events in PAH. Materials and Methods Eighty-six consecutive patients were enrolled in this study. RV hemodynamic parameters were measured by right heart catheterization (RHC). RV function was assessed using two-dimensional speckle-tracking echocardiography and three-dimensional transthoracic echocardiography (3DTTE) to evaluate RV free wall global strain (RVFS) and RVEF. Conclusions RVEF measured by 3DTTE could be a useful parameter for noninvasively assessing RV hemodynamics and predicting the clinical outcomes in PAH patients. PMID:27893420

  19. Myocardial Stiffness in Patients with Heart Failure and a Preserved Ejection Fraction: Contributions of Collagen and Titin

    PubMed Central

    Zile, Michael R.; Baicu, Catalin F.; Ikonomidis, John; Stroud, Robert E.; Nietert, Paul J.; Bradshaw, Amy D.; Slater, Rebecca; Palmer, Bradley M.; Van Buren, Peter; Meyer, Markus; Redfield, Margaret; Bull, David; Granzier, Henk; LeWinter, Martin M.

    2015-01-01

    Background The purpose of this study was to determine whether patients with heart failure and a preserved ejection fraction (HFpEF) have an increase in passive myocardial stiffness and the extent to which discovered changes are dependent on changes in extracellular matrix fibrillar collagen and/or cardiomyocyte titin. Methods and Results Seventy patients undergoing coronary artery bypass grafting underwent an echocardiogram, plasma biomarker determination, and intra-operative left ventricular (LV) epicardial anterior wall biopsy. Patients were divided into 3 groups: referent control (n=17, no hypertension or diabetes), hypertension (HTN) without(-) HFpEF (n=31), and HTN with(+) HFpEF (n=22). One or more of the following studies were performed on the biopsies: passive stiffness measurements to determine total, collagen-dependent and titin-dependent stiffness (differential extraction assay), collagen assays (biochemistry or histology), or titin isoform and phosphorylation assays. Compared with controls, patients with HTN(-)HFpEF had no change in LV end diastolic pressure (LVEDP), myocardial passive stiffness, collagen, or titin phosphorylation but had an increase in biomarkers of inflammation (CRP, sST2, TIMP-1). Compared with both control and HTN(-)HFpEF, patients with HTN(+)HFpEF had increased LVEDP, left atrial volume, NT-proBNP, total, collagen-dependent and titin-dependent stiffness, insoluble collagen, increased titin phosphorylation on PEVK S11878(S26), reduced phosphorylation on N2B S4185(S469), and increased biomarkers of inflammation. Conclusions Hypertension in the absence of HFpEF, did not alter passive myocardial stiffness. Patients with HTN(+)HFpEF had a significant increase in passive myocardial stiffness; collagen-dependent and titin-dependent stiffness were increased. These data suggest that the development of HFpEF is dependent on changes in both collagen and titin homeostasis. PMID:25637629

  20. Cardiac output response to exercise in relation to metabolic demand in heart failure with preserved ejection fraction

    PubMed Central

    Abudiab, Muaz M.; Redfield, Margaret M.; Melenovsky, Vojtech; Olson, Thomas P.; Kass, David A.; Johnson, Bruce D.; Borlaug, Barry A.

    2013-01-01

    Aims Exercise intolerance is a hallmark of heart failure with preserved ejection fraction (HFpEF), yet its mechanisms remain unclear. The current study sought to determine whether increases in cardiac output (CO) during exercise are appropriately matched to metabolic demands in HFpEF. Methods and results Patients with HFpEF (n = 109) and controls (n = 73) exercised to volitional fatigue with simultaneous invasive (n = 96) or non-invasive (n = 86) haemodynamic assessment and expired gas analysis to determine oxygen consumption (VO2) during upright or supine exercise. At rest, HFpEF patients had higher LV filling pressures but similar heart rate, stroke volume, EF, and CO. During supine and upright exercise, HFpEF patients displayed lower peak VO2 coupled with blunted increases in heart rate, stroke volume, EF, and CO compared with controls. LV filling pressures increased dramatically in HFpEF patients, with secondary elevation in pulmonary artery pressures. Reduced peak VO2 in HFpEF patients was predominantly attributable to CO limitation, as the slope of the increase in CO relative to VO2 was 20% lower in HFpEF patients (5.9 ± 2.5 vs. 7.4 ± 2.6 L blood/L O2, P = 0.0005). While absolute increases in arterial–venous O2 difference with exercise were similar in HFpEF patients and controls, augmentation in arterial–venous O2 difference relative to VO2 was greater in HFpEF patients (8.9 ± 3.4 vs. 5.5 ± 2.0 min/dL, P < 0.0001). These differences were observed in the total cohort and when upright and supine exercise modalities were examined individually. Conclusion While diastolic dysfunction promotes congestion and pulmonary hypertension with stress in HFpEF, reduction in exercise capacity is predominantly related to inadequate CO relative to metabolic needs. PMID:23426022

  1. A pilot study of angiogenin in heart failure with preserved ejection fraction: a novel potential biomarker for diagnosis and prognosis?

    PubMed

    Jiang, Hong; Zhang, Lei; Yu, Ying; Liu, Ming; Jin, Xuejuan; Zhang, Peipei; Yu, Peng; Zhang, Shuning; Zhu, Hongmin; Chen, Ruizhen; Zou, Yunzeng; Ge, Junbo

    2014-11-01

    Characteristics of heart failure with preserved ejection fraction (HFPEF) have not yet been fully understood. The objectives of this pilot study are to detect protein expression profile in the sera of HFPEF patients, and to identify potential biomarkers for the disease. Five hundred and seven proteins were detected in the sera of healthy volunteers and patients with either HFPEF or hypertension using antibody microarrays (three in each group). The results showed that the serum concentrations of 17 proteins (e.g. angiogenin, activin A and artemin) differed considerably between HFPEF and non-HFPEF patients (hypertensive patients and healthy controls), while a protein expression pattern distinct from that in non-HFPEF patients was associated with HFPEF patients. The up-regulation of angiogenin in both HFPEF patients with LVEF ≥50% (P = 0.004) and a subset of HFPEF patients with LVEF = 41-49% (P < 0.001) was further validated in 16 HFPEF patients and 16 healthy controls. Meanwhile, angiogenin distinguished HFPEF patients from controls with a mean area under the receiver operating characteristic curve of 0.88 (P < 0.001) and a diagnostic cut-off point of 426 ng/ml. Moreover, the angiogenin levels in HFPEF patients were positively correlated with Lg(N-terminal pro-B-type natriuretic peptide, NT-proBNP) (P < 0.001). In addition, high angiogenin level (≥426 ng/ml) was a predictor of all-cause death within a short-term follow-up duration, but not in the longer term of 36 months. This pilot study indicates that the aforementioned 17 potential biomarkers, such as angiogenin, may hold great promise for both diagnosis and prognosis assessment of HFPEF.

  2. Prognostic significance of tPA/PAI-1 complex in patients with heart failure and preserved ejection fraction.

    PubMed

    Winter, Max-Paul; Kleber, Marcus E; Koller, Lorenz; Sulzgruber, Patrick; Scharnagl, Hubert; Delgado, Graciela; Goliasch, Georg; März, Winfried; Niessner, Alexander

    2017-02-28

    Heart failure with preserved ejection fraction (HFpEF) represents a major epidemic, clinical and public health problem with rising patient numbers every year. Traditional markers for heart failure have been shown to be of limited sensitivity in patients with HFpEF, as those do not reflect pathophysiology of the disease properly. Dysregulation of haemostasis is thought to be central for the initiation and progression of HFpEF. For this reason, we aimed to assess markers of fibrinolytic activity as potential biomarkers for risk assessment in patients with HFpEF. We evaluated blood coagulation parameters in 370 patients with HFpEF included in the LUdwigshafen Risk and Cardiovascular Health (LURIC) study. Within an observation period of 9.7 years, 40 percent of these patients died from any cause. tPA/PAI-1 complex significantly predicted all-cause mortality with a hazard ratio (HR) of 1.24 (95 % confidence interval [CI] 1.04-1.47) per increase of 1 SD and cardiovascular mortality with a HR 1.26 (95 % CI 1.02-1.56) per increase of 1 SD. Both associations remained significant after adjustment for cardiovascular risk factors, N-terminal pro-B-type natriuretic peptide (NT-proBNP) and frequent HFpEF- related comorbidities. Importantly, tPA/PAI-1 complex had additional prognostic value above and beyond NT-proBNP as indicated by integrated discrimination improvement (0.0157, p=0.017). In conclusion, the concentration of tPA/PAI-1 complex is an independent predictor of mortality from all causes and from cardiovascular causes in patients with HFpEF. The concomitant measurement of tPA/PAI-1 complex might be useful in clinical practice to add prognostic value to traditional markers of heart failure.

  3. The Relationships between Body Mass Index and Left Ventricular Diastolic Function in a Structurally Normal Heart with Normal Ejection Fraction

    PubMed Central

    Jin, Han-Young; Jang, Jae-Sik; Yang, Tae-Hyun; Kim, Dae-Kyeong; Kim, Dong-Soo

    2017-01-01

    Background We conducted research to determine the effect of the weight on left ventricular (LV) diastolic function in Asians, who are at greater risk of cardiovascular events compared to individuals from Western countries with similar body mass indices (BMIs). Methods We studied 543 participants with structurally normal hearts and normal ejection fractions. Participants were classified as normal-weight (BMI < 23.0 kg/m2), overweight (BMI 23.0–27.4 kg/m2), or obese (BMI ≥ 27.5 kg/m2). Peak E velocity, peak A velocity, and E′ velocity were measured and E/E′ was calculated. Results Overweight participants had lower E than normal-weight participants (p = 0.001). E′ velocities in overweight and obese participants were less than those in normal weight participants (both p < 0.001). The E/E′ ratio in obese participants was higher compared to the value in normal-weight participants (p < 0.001) and overweight participants (p = 0.025). BMI was associated with E (R = −0.108), A (R = 0.123), E′ (R = −0.229), and E/E′ ratio (R = 0.138) (all p < 0.05). In multivariate analyses, BMI was independently associated with higher A, lower E′, and higher E/E′. The risk of diastolic dysfunction was significantly higher among overweight [adjusted odds ratio: 2.088; 95% confidence interval (CI): 1.348–3.235; p = 0.001] and obese participants (adjusted odds ratio: 5.910; 95% CI: 2.871–12.162; p < 0.001) compared to normal-weight participants. Conclusion Obesity and overweight independently predicted diastolic dysfunction. An optimal body weight lower than the universal cut-off is reasonable for preventing LV heart failure in Asians.

  4. Surgical Experience and Long-term Results of Baroreflex Activation Therapy for Heart Failure With Reduced Ejection Fraction.

    PubMed

    Weaver, Fred A; Abraham, William T; Little, William C; Butter, Christian; Ducharme, Anique; Halbach, Marcel; Klug, Didier; Lovett, Eric G; Madershahian, Navid; Müller-Ehmsen, Jochen; Schafer, Jill E; Senni, Michele; Swarup, Vijay; Wachter, Rolf; Zile, Michael R

    2016-01-01

    The purpose of this publication is to describe the intraoperative experience along with long-term safety and efficacy of the second-generation baroreflex activation therapy (BAT) system in patients with heart failure (HF) and reduced ejection fraction HF (HFrEF). In a randomized trial of New York Heart Association Class III HFrEF, 140 patients were assigned 1:1 to receive BAT plus medical therapy or medical therapy alone. Procedural information along with safety and efficacy data were collected and analyzed over 12 months. Within the cohort of 71 patients randomized to BAT, implant procedure time decreased with experience, from 106 ± 37 minutes on the first case to 83 ± 32 minutes on the third case. The rate of freedom from system- and procedure-related complications was 86% through 12 months, with the percentage of days alive without a complication related to system, procedure, or underlying cardiovascular condition identical to the control group. The complications that did occur were generally mild and short-lived. Overall, 12 months therapeutic benefit from BAT was consistent with previously reported efficacy through 6 months: there was a significant and sustained beneficial treatment effect on New York Heart Association functional Class, quality of life, 6-minute hall walk distance, plasma N-terminal pro-brain natriuretic peptide, and systolic blood pressure. This was true for the full trial cohort and a predefined subset not receiving cardiac resynchronization therapy. There is a rapid learning curve for the specialized procedures entailed in a BAT system implant. BAT system implantation is safe with the therapeutic benefits of BAT in patients with HFrEF being substantial and maintained for at least 1 year.

  5. Echocardiography and invasive hemodynamics during stress testing for diagnosis of heart failure with preserved ejection fraction: an experimental study.

    PubMed

    Leite, Sara; Oliveira-Pinto, José; Tavares-Silva, Marta; Abdellatif, Mahmoud; Fontoura, Dulce; Falcão-Pires, Inês; Leite-Moreira, Adelino F; Lourenço, André P

    2015-06-15

    Inclusion of exercise testing in diagnostic guidelines for heart failure with preserved ejection fraction (HFpEF) has been advocated, but the target population, technical challenges, and underlying pathophysiological complexity raise difficulties to implementation. Hemodynamic stress tests may be feasible alternatives. Our aim was to test Trendelenburg positioning, phenylephrine, and dobutamine in the ZSF1 obese rat model to find echocardiographic surrogates for end-diastolic pressure (EDP) elevation and HFpEF. Seventeen-week-old Wistar-Kyoto, ZSF1 lean, and obese rats (n = 7 each) randomly and sequentially underwent (crossover) Trendelenburg (30°), 5 μg·Kg(-1)·min(-1) dobutamine, and 7.5 μg·Kg(-1)·min(-1) phenylephrine with simultaneous left ventricular (LV) pressure-volume loop and echocardiography evaluation under halogenate anesthesia. Effort testing with maximum O2 consumption (V̇o 2 max) determination was performed 1 wk later. Obese ZSF1 showed lower effort tolerance and V̇o 2 max along with higher resting EDP. Both Trendelenburg and phenylephrine increased EDP, whereas dobutamine decreased it. Significant correlations were found between EDP and 1) peak early filling Doppler velocity of transmitral flow (E) to corresponding myocardial tissue Doppler velocity (E') ratio, 2) E to E-wave deceleration time (E/DT) ratio, and 3) left atrial area (LAA). Diagnostic efficiency of E/DT*LAA by receiver-operating characteristic curve analysis for elevation of EDP above a cut-off of 13 mmHg during hemodynamic stress was high (area under curve, AUC = 0.95) but not higher than that of E/E' (AUC = 0.77, P = 0.15). Results in ZSF1 obese rats suggest that noninvasive echocardiography after hemodynamic stress induced by phenylephrine or Trendelenburg can enhance diagnosis of stable HFpEF and constitute an alternative to effort testing.

  6. The Prognostic Importance of Impaired Systolic Function in Heart Failure with Preserved Ejection Fraction and the Impact of Spironolactone

    PubMed Central

    Shah, Amil M.; Claggett, Brian; Sweitzer, Nancy K.; Shah, Sanjiv J.; Anand, Inder S.; Liu, Li; Pitt, Bertram; Pfeffer, Marc A.; Solomon, Scott D.

    2015-01-01

    Background Impairment in left ventricular (LV) systolic function has been described in heart failure with preserved ejection fraction (HFpEF), but its prognostic relevance is not known. We determined whether LV longitudinal strain (LS) is predictive of cardiovascular (CV) outcomes in HFpEF beyond clinical and conventional echocardiographic measures. Methods and Results LS was assessed by 2D speckle-tracking echocardiography at baseline in 447 HFpEF patients enrolled in the Treatment Of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial. At a median follow-up of 2.6 (IQR 1.5–3.9) years, 115 patients experienced the primary composite outcome of CV death, HF hospitalization, or aborted cardiac arrest. Impaired LS, defined as an absolute LS<15.8%, was present in 52% of patients and was predictive of the composite outcome (adjusted HR 2.14, 95% CI 1.26–3.66; p=0.005), CV death alone (adjusted HR 3.20, 95% CI 1.44–7.12; p=0.004), and HF hospitalization alone (adjusted HR 2.23, 95% CI 1.16–4.28; p=0.016) after adjusting for clinical and conventional echocardiographic variables. LS was the strongest echocardiographic predictor of the composite outcome. Exploratory analysis in a subset of 131 patients with follow-up LS assessed after 12–18 months demonstrated a trend towards improvement in LS associated with spironolactone in patients enrolled in the Americas but not in Russia or Georgia. Conclusions Impaired LV systolic function is a powerful predictor of HF hospitalization, CV death, or aborted cardiac arrest in HFpEF, independent of clinical predictors. Impaired LS represents a novel imaging biomarker to identify HFpEF patients at particularly high risk for CV morbidity and mortality. Clinical Trial Registration Information Clinicaltrials.gov. Identifier NCT00094302. PMID:26130119

  7. Alterations in myostatin expression are associated with changes in cardiac left ventricular mass but not ejection fraction in the mouse.

    PubMed

    Artaza, Jorge N; Reisz-Porszasz, Suzanne; Dow, Joan S; Kloner, Robert A; Tsao, James; Bhasin, Shalender; Gonzalez-Cadavid, Nestor F

    2007-07-01

    Myostatin (Mst) is a negative regulator of skeletal muscle in humans and animals. It is moderately expressed in the heart of sheep and cattle, increasing considerably after infarction. Genetic blockade of Mst expression increases cardiomyocyte growth. We determined whether Mst overexpression in the heart of transgenic mice reduces left ventricular size and function, and inhibits in vitro cardiomyocyte proliferation. Young transgenic mice overexpressing Mst in the heart (Mst transgenic mice (TG) under a muscle creatine kinase (MCK) promoter active in cardiac and skeletal muscle, and Mst knockout (Mst (-/-)) mice were used. Xiscan angiography revealed that the left ventricular ejection fraction did not differ between the Mst TG and the Mst (-/-) mice, when compared with their respective wild-type strains, despite the decrease in whole heart and left ventricular size in Mst TG mice, and their increase in Mst (-/-) animals. The expected changes in cardiac Mst were measured by RT-PCR and western blot. Mst and its receptor (ActRIIb) were detected by RT-PCR in rat H9c2 cardiomyocytes. Transfection of H9c2 with plasmids expressing Mst under muscle-specific creatine kinase promoter, or cytomegalovirus promoter, enhanced p21 and reduced cdk2 expression, when assessed by western blot. A decrease in cell number occurred by incubation with recombinant Mst (formazan assay), without affecting apoptosis or cardiomyocyte size. Anti-Mst antibody increased cardiomyocyte replication, whereas transfection with the Mst-expressing plasmids inhibited it. In conclusion, Mst does not affect cardiac systolic function in mice overexpressing or lacking the active protein, but it reduces cardiac mass and cardiomyocyte proliferation.

  8. Serum Soluble Urokinase-Type Plasminogen Activator Receptor Is Associated with Low Left Ventricular Ejection Fraction and Elevated Plasma Brain-Type Natriuretic Peptide Level

    PubMed Central

    Fujita, Shu-ichi; Tanaka, Suguru; Maeda, Daichi; Morita, Hideaki; Fujisaka, Tomohiro; Takeda, Yoshihiro; Ito, Takahide; Ishizaka, Nobukazu

    2017-01-01

    Background Recent studies have suggested that soluble urokinase plasminogen activator receptor (suPAR), a biomarker of subclinical levels of inflammation, is significantly correlated with cardiovascular events. Purpose We investigated the association between suPAR and left ventricular ejection fraction (LVEF), left ventricular mass index (LVMI), and plasma B-type natriuretic peptide (BNP) among cardiac inpatients. Methods and Results In total, 242 patients (mean age 71.3 ± 9.8 years; 70 women) admitted to the cardiology department were enrolled in the study. suPAR was significantly correlated with LVEF (R = -0.24, P<0.001), LVMI (R = 0.16, P = 0.014) and BNP (R = 0.46, P<0.001). In logistic regression analysis, the highest suPAR tertile (> 3236 pg/mL) was associated with low LVEF (< 50%) and elevated BNP (> 300 pg/mL) with an odds ratio of 3.84 (95% confidence interval [CI], 1.22–12.1) and 5.36 (95% CI, 1.32–21.8), respectively, after adjusting for age, sex, log-transformed estimated glomerular filtration rate (log(eGFR)), C-reactive protein, and diuretic use. The association between suPAR and LVMI was not statistically significant. In multivariate receiver operating characteristic analysis, addition of log(suPAR) to the combination of age, sex, log(eGFR) and CRP incrementally improved the prediction of low LVEF (area under the curve [AUC], 0.827 to 0.852, P = 0.046) and BNP ≥ 300 pg/mL (AUC, 0.869 to 0.906; P = 0.029). Conclusions suPAR was associated with low LVEF and elevated BNP, but not with left ventricular hypertrophy, independent of CRP, renal function, and diuretic use among cardiac inpatients who were not undergoing chronic hemodialysis. PMID:28135310

  9. One-Year Outcomes After Transcatheter Insertion of an Interatrial Shunt Device for the Management of Heart Failure With Preserved Ejection Fraction

    PubMed Central

    Hasenfuß, Gerd; Neuzil, Petr; Post, Martijn C.; Doughty, Robert; Trochu, Jean-Noël; Kolodziej, Adam; Westenfeld, Ralf; Penicka, Martin; Rosenberg, Mark; Walton, Antony; Muller, David; Walters, Darren; Hausleiter, Jorg; Raake, Philip; Petrie, Mark C.; Bergmann, Martin; Jondeau, Guillaume; Feldman, Ted; van Veldhuisen, Dirk J.; Ponikowski, Piotr; Silvestry, Frank E.; Burkhoff, Dan; Hayward, Christopher

    2016-01-01

    Background— Heart failure with preserved ejection fraction has a complex pathophysiology and remains a therapeutic challenge. Elevated left atrial pressure, particularly during exercise, is a key contributor to morbidity and mortality. Preliminary analyses have demonstrated that a novel interatrial septal shunt device that allows shunting to reduce the left atrial pressure provides clinical and hemodynamic benefit at 6 months. Given the chronicity of heart failure with preserved ejection fraction, evidence of longer-term benefit is required. Methods and Results— Patients (n=64) with left ventricular ejection fraction ≥40%, New York Heart Association class II–IV, elevated pulmonary capillary wedge pressure (≥15 mm Hg at rest or ≥25 mm Hg during supine bicycle exercise) participated in the open-label study of the interatrial septal shunt device. One year after interatrial septal shunt device implantation, there were sustained improvements in New York Heart Association class (P<0.001), quality of life (Minnesota Living with Heart Failure score, P<0.001), and 6-minute walk distance (P<0.01). Echocardiography showed a small, stable reduction in left ventricular end-diastolic volume index (P<0.001), with a concomitant small stable increase in the right ventricular end-diastolic volume index (P<0.001). Invasive hemodynamic studies performed in a subset of patients demonstrated a sustained reduction in the workload corrected exercise pulmonary capillary wedge pressure (P<0.01). Survival at 1 year was 95%, and there was no evidence of device-related complications. Conclusions— These results provide evidence of safety and sustained clinical benefit in heart failure with preserved ejection fraction patients 1 year after interatrial septal shunt device implantation. Randomized, blinded studies are underway to confirm these observations. Clinical Trial Registration— URL: https://www.clinicaltrials.gov. Unique identifier: NCT01913613. PMID:27852653

  10. Influence of Left Ventricular Stroke Volume on Incident Heart Failure in a Population With Preserved Ejection Fraction (from the Strong Heart Study).

    PubMed

    De Marco, Marina; Gerdts, Eva; Mancusi, Costantino; Roman, Mary J; Lønnebakken, Mai Tone; Lee, Elisa T; Howard, Barbara V; Devereux, Richard B; de Simone, Giovanni

    2017-04-01

    At a given level of left ventricular (LV) systolic function, LV pump performance (assessed by stroke index [SVi]) may differ, depending on LV size. We evaluated whether low SVi may be considered a marker of risk for incident congestive heart failure (HF), independent of LV geometry and systolic function, assessed by ejection fraction (EF) or midwall fractional shortening (MFS), in a large population-based sample with normal EF. Clinical and echocardiographic data from the second Strong Heart Study (SHS) examination, including 2,885 American Indians (59 ± 8 years; 63% women) with normal EF (EF ≥51% in men and EF ≥55% in women) and without prevalent HF or significant valve disease, were analyzed. Low SVi was defined as SVi ≤22 ml/m(2.04). Low SVi was more common among men and associated with lower body mass index, systolic blood pressure, LV mass index, left atrial dimension, EF, and MFS and with higher relative wall thickness. During a mean 12-year follow-up, 209 participants developed HF and 246 had acute myocardial infarction. In Cox regression analysis, low SVi was associated with higher risk of incident HF (hazard ratio 1.38; 95% confidence interval 1.06 to 1.80), independently of age, gender, body mass index, heart rate, hypertension, prevalent cardiovascular disease, left atrial dimension index, LV mass index, LV concentric geometry, EF or MFS, and abnormal wall motion, also accounting for myocardial infarction as a competing risk event. In conclusion, in the SHS, low SVi was associated with higher incident rate of HF, independently of LV geometry and systolic function and other major confounders.

  11. Patient barriers to implantable cardioverter defibrillator implantation for the primary prevention of sudden cardiac death in patients with heart failure and reduced ejection fraction

    PubMed Central

    Chan, Laura Lihua; Lim, Choon Pin; Aung, Soe Tin; Quetua, Paul; Ho, Kah Leng; Chong, Daniel; Teo, Wee Siong; Sim, David; Ching, Chi Keong

    2016-01-01

    INTRODUCTION Device therapy is efficacious in preventing sudden cardiac death (SCD) in patients with reduced ejection fraction. However, few who need the device eventually opt to undergo implantation and even fewer reconsider their decisions after deliberation. This is due to many factors, including unresolved patient barriers. This study identified the factors that influenced patients’ decision to decline implantable cardioverter defibrillator (ICD) implantation, and those that influenced patients who initially declined an implant to reconsider having one. METHODS A single-centre survey was conducted among 240 patients who had heart failure with reduced ejection fraction and met the ICD implantation criteria, but had declined ICD implantation. RESULTS Participants who refused ICD implantation were mostly male (84%), Chinese (71%), married (72%), currently employed (54%), and had up to primary or secondary education (78%) and monthly income of < SGD 3,000 (51%). Those who were more likely to reconsider their decision were aware that SCD was a consequence of heart failure with reduced ejection fraction, knowledgeable of the preventive role of ICDs, currently employed and aware that their doctor strongly recommended the implant. Based on multivariate analysis, knowledge of the role of ICDs for primary prophylaxis was the most important factor influencing patient decision. CONCLUSION This study identified the demographic and social factors of patients who refused ICD therapy. Knowledge of the role of ICDs in preventing SCD was found to be the strongest marker for reconsidering ICD implantation. Measures to address this information gap may lead to higher rates of ICD implantation. PMID:27075476

  12. Aging and Rejuvenation with Fractional Derivatives

    DTIC Science & Technology

    2007-11-02

    Science, University of North Texas, P. O. Box 311427, Denton, Texas 76203-1427, USA 2Dipartimento di Fisica dell’Università di Pisa and INFM, via...interval 2,m,3, yield a generalized master equation equivalent to the sum of an ordinary Markov contribution and a fractional derivative term. We show...though these processes are associated with quite different physical phenomena [14]. His general argu- ments rested on three assumptions: (1) microscopic

  13. Guideline-Directed Medication Use in Patients With Heart Failure With Reduced Ejection Fraction in India: American College of Cardiology's PINNACLE India Quality Improvement Program.

    PubMed

    Pokharel, Yashashwi; Wei, Jessica; Hira, Ravi S; Kalra, Ankur; Shore, Supriya; Kerkar, Prafulla G; Kumar, Ganesh; Risch, Samantha; Vicera, Veronique; Oetgen, William J; Deswal, Anita; Turakhia, Mintu P; Glusenkamp, Nathan; Virani, Salim S

    2016-03-01

    Little is known about the use of guideline-directed medical therapy (GDMT) in outpatients with heart failure with reduced left ventricular ejection fraction (HFrEF; ≤40%) in India. Our objective was to understand the use of GDMT in outpatients with HFrEF in India. The Practice Innovation And Clinical Excellence (PINNACLE) India Quality Improvement Program (PIQIP) is a registry for cardiovascular quality improvement in India supported by the American College of Cardiology Foundation. Between January 2008 and September 2014, we evaluated documentation of use of angiotensin-converting enzyme inhibitors (ACEIs)/angiotensin receptor blockers (ARBs) and β-blockers, or both, among outpatients with HFrEF seeking care in 10 centers enrolled in the PIQIP registry. Among 75 639 patients in the PIQIP registry, 34 995 had EF reported, and 15 870 had an EF ≤40%. The mean age was 56 years; 23% were female. Hypertension, diabetes, coronary artery disease, and myocardial infarction were present in 37%, 23%, 27%, and 17%, respectively. Use of ACEIs/ARBs, β-blockers, and both were documented in 33.5%, 34.9%, and 29.6% of patients, respectively. The documentation of GDMT was higher in men, in patients age ≥65 years, and in those with presence of hypertension, diabetes, or coronary artery disease. Documentation of GDMT gradually increased over the study period. Among patients enrolled in the PIQIP registry, about two-thirds of patients with EF ≤40% did not have documented receipt of GDMT. This study is an initial step toward improving adherence to GDMT in India and highlights the feasibility of examining quality of care in HFrEF in a resource-limited setting.

  14. The Effect of Cardiac Rehabilitation Exercise Training on Cardiopulmonary Function in Ischemic Cardiomyopathy With Reduced Left Ventricular Ejection Fraction

    PubMed Central

    2016-01-01

    Objective To observe the effect and safety of cardiac rehabilitation (CR) exercise in ischemic cardiomyopathy and to compare the results between patients with preserved left ventricular ejection fraction (LVEF) and reduced LVEF. Methods Patients with ischemic cardiomyopathy with LVEF <50% were included as subjects. The patients were classified into the preserved LVEF (pLVEF; LVEF 41%–49%) group and the reduced LVEF (rLVEF; LVEF ≤40%) group. Patients underwent hourly aerobic exercise training sessions with an intensity of 60%–85% of heart rate reserve, three times a week for 6 weeks. Graded exercise test and transthoracic echocardiogram were performed in all study patients before and after completion of the CR exercise program. Results After completion of the CR exercise program, both groups (pLVEF, n=30; rLVEF, n=18) showed significant increases in LVEF and VO2max. In the pLVEF group, LVEF and VO2max increased from 45.1%±4.8% to 52.5%±9.6% (p<0.001) and from 24.1±6.3 to 28.1±8.8 mL/kg/min (p=0.002), respectively. In the rLVEF group, LVEF and VO2max increased from 29.7%±7.7% to 37.6%±10.3% (p<0.001) and from 17.6±4.7 to 21.2±5.1 mL/kg/min (p<0.001), respectively. Both groups completed their exercise program safely. Conclusion In both groups, patients with ischemic cardiomyopathy who completed a 6-week supervised CR exercise program demonstrated remarkable improvements in cardiopulmonary function. This result implies that neither of the two groups showed higher efficacy in comparison to each other, but we can conclude that CR exercise in the rLVEF group was as effective and safe as that in the pLVEF group. PMID:27606271

  15. Assessing left ventricular systolic dysfunction after myocardial infarction: are ejection fraction and dP/dtmax complementary or redundant?

    PubMed Central

    Ishikawa, Kiyotake; Chemaly, Elie R.; Tilemann, Lisa; Fish, Kenneth; Ladage, Dennis; Aguero, Jaime; Vahl, Torsten; Santos-Gallego, Carlos; Kawase, Yoshiaki

    2012-01-01

    Among the various cardiac contractility parameters, left ventricular (LV) ejection fraction (EF) and maximum dP/dt (dP/dtmax) are the simplest and most used. However, these parameters are often reported together, and it is not clear if they are complementary or redundant. We sought to compare the discriminative value of EF and dP/dtmax in assessing systolic dysfunction after myocardial infarction (MI) in swine. A total of 220 measurements were obtained. All measurements included LV volumes and EF analysis by left ventriculography, invasive ventricular pressure tracings, and echocardiography. Baseline measurements were performed in 132 pigs, and 88 measurements were obtained at different time points after MI creation. Receiver operator characteristic (ROC) curves to distinguish the presence or absence of an MI revealed a good predictive value for EF [area under the curve (AUC): 0.998] but not by dP/dtmax (AUC: 0.69, P < 0.001 vs. EF). Dividing dP/dtmax by LV end-diastolic pressure and heart rate (HR) significantly increased the AUC to 0.87 (P < 0.001 vs. dP/dtmax and P < 0.001 vs. EF). In naïve pigs, the coefficient of variation of dP/dtmax was twice than that of EF (22.5% vs. 9.5%, respectively). Furthermore, in n = 19 pigs, dP/dtmax increased after MI. However, echocardiographic strain analysis of 23 pigs with EF ranging only from 36% to 40% after MI revealed significant correlations between dP/dtmax and strain parameters in the noninfarcted area (circumferential strain: r = 0.42, P = 0.05; radial strain: r = 0.71, P < 0.001). In conclusion, EF is a more accurate measure of systolic dysfunction than dP/dtmax in a swine model of MI. Despite the variability of dP/dtmax both in naïve pigs and after MI, it may sensitively reflect the small changes of myocardial contractility. PMID:22307667

  16. Assessing left ventricular systolic dysfunction after myocardial infarction: are ejection fraction and dP/dt(max) complementary or redundant?

    PubMed

    Ishikawa, Kiyotake; Chemaly, Elie R; Tilemann, Lisa; Fish, Kenneth; Ladage, Dennis; Aguero, Jaime; Vahl, Torsten; Santos-Gallego, Carlos; Kawase, Yoshiaki; Hajjar, Roger J

    2012-04-01

    Among the various cardiac contractility parameters, left ventricular (LV) ejection fraction (EF) and maximum dP/dt (dP/dt(max)) are the simplest and most used. However, these parameters are often reported together, and it is not clear if they are complementary or redundant. We sought to compare the discriminative value of EF and dP/dt(max) in assessing systolic dysfunction after myocardial infarction (MI) in swine. A total of 220 measurements were obtained. All measurements included LV volumes and EF analysis by left ventriculography, invasive ventricular pressure tracings, and echocardiography. Baseline measurements were performed in 132 pigs, and 88 measurements were obtained at different time points after MI creation. Receiver operator characteristic (ROC) curves to distinguish the presence or absence of an MI revealed a good predictive value for EF [area under the curve (AUC): 0.998] but not by dP/dt(max) (AUC: 0.69, P < 0.001 vs. EF). Dividing dP/dt(max) by LV end-diastolic pressure and heart rate (HR) significantly increased the AUC to 0.87 (P < 0.001 vs. dP/dt(max) and P < 0.001 vs. EF). In naïve pigs, the coefficient of variation of dP/dt(max) was twice than that of EF (22.5% vs. 9.5%, respectively). Furthermore, in n = 19 pigs, dP/dt(max) increased after MI. However, echocardiographic strain analysis of 23 pigs with EF ranging only from 36% to 40% after MI revealed significant correlations between dP/dt(max) and strain parameters in the noninfarcted area (circumferential strain: r = 0.42, P = 0.05; radial strain: r = 0.71, P < 0.001). In conclusion, EF is a more accurate measure of systolic dysfunction than dP/dt(max) in a swine model of MI. Despite the variability of dP/dt(max) both in naïve pigs and after MI, it may sensitively reflect the small changes of myocardial contractility.

  17. Adenosine receptor expression in an experimental animal model of myocardial infarction with preserved left ventricular ejection fraction.

    PubMed

    Cabiati, Manuela; Martino, Alessandro; Mattii, Letizia; Caselli, Chiara; Prescimone, Tommaso; Lionetti, Vincenzo; Morales, Maria-Aurora; Del Ry, Silvia

    2014-07-01

    Adenosine, a purine nucleoside and a "retaliatory metabolite" in ischemia, is ubiquitous in the body and increases 100-fold during ischemia. Its biological actions are mediated by four adenosine receptors (ARs): A(1), A(2A), A(2B) and A(3). The aim of this study was to determine possible myocardial alterations in AR expression in an experimental animal model of myocardial infarction (MI) with a preserved left ventricular (LV) ejection fraction. LV tissue was collected from sexually mature male farm pigs with MI (n = 6) induced by permanent surgical ligation of the left anterior descending coronary artery and from five healthy pigs (C). mRNA expression of A(1)R, A(2A)R, A(2B)R, A(3)R and TNF-α was determined by real-time PCR in tissue collected from border (BZ) and remote zones (RZ) of the infarcted area and from LV of C. BZ, RZ and samples of C were stained immunohistochemically to investigate A(3)R immunoreaction. After 4 weeks a different regulation of ARs was observed. A(1)R mRNA expression was significantly lower in the infarct regions than in controls (C = 0.75 ± 0.2, BZ = 0.05 ± 0.2, RZ = 0.07 ± 0.02 p = 0.0025, p = 0.0016, C vs. BZ and RZ, respectively). Conversely A(3)R was higher in infarct areas (C = 0.94 ± 0.2, BZ = 2.85 ± 0.5, RZ = 3.48 ± 1.0, p = 0.048 C vs. RZ). No significant differences were observed for A(2A)R (C = 1.58 ± 0.6, BZ = 0.42 ± 0.1, RZ = 1.37 ± 0.6) and A(2B)R (C = 1.66 ± 0.2, BZ = 1.54 ± 0.5, RZ = 1.25 ± 0.4). A(3)R expression was confirmed by immunohistochemical analysis and was principally localized in cardiomyocytes. TNF-α mRNA results were: C 0.41 ± 0.25; BZ 1.60 ± 0.19; RZ 0.17 ± 0.04. The balance between A(1)R and A(3)R as well as between A(2A)R and A(2B)R was consistent with adaptative retaliatory anti-ischemic adenosinergic changes in the infarcted heart with preserved LV function.

  18. Fetal cardiac ventricular volume, cardiac output, and ejection fraction determined with four-dimensional ultrasound using Spatio-Temporal Image Correlation (STIC) and Virtual Organ Computed-aided AnaLysis (VOCAL™)

    PubMed Central

    Hamill, Neil; Yeo, Lami; Romero, Roberto; Hassan, Sonia S.; Myers, Stephen A.; Mittal, Pooja; Kusanovic, Juan Pedro; Balasubramaniam, Mamtha; Chaiworapongsa, Tinnakorn; Vaisbuch, Edi; Espinoza, Jimmy; Gotsch, Francesca; Goncalves, Luis F.; Lee, Wesley

    2011-01-01

    Objective To quantify fetal cardiovascular parameters with Spatio-Temporal Image Correlation (STIC) and Virtual Organ Computed-aided AnaLysis (VOCAL™) utilizing the sub-feature: “Contour Finder: Trace”. Study Design A cross-sectional study was designed consisting of patients with normal pregnancies between 19 and 40 weeks of gestation. After STIC datasets were acquired, analysis was performed offline (4DView) and the following cardiovascular parameters were evaluated: ventricular volume in end systole and end diastole, stroke volume, cardiac output, and ejection fraction. To account for fetal size, cardiac output was also expressed as a function of head circumference, abdominal circumference, or femoral diaphysis length. Regression models were fitted for each cardiovascular parameter to assess the effect of gestational age and paired comparisons were made between the left and right ventricles. Results 1) Two hundred and seventeen patients were retrospectively identified, of whom 184 had adequate STIC datasets (85% acceptance); 2) ventricular volume, stroke volume, cardiac output, and adjusted cardiac output increased with gestational age; whereas, the ejection fraction decreased as gestation advanced; 3) the right ventricle was larger than the left in both systole (Right: 0.50 ml, IQR: 0.2 – 0.9; vs. Left: 0.27 ml, IQR: 0.1 – 0.5; p<0.001) and diastole (Right: 1.20 ml, IQR: 0.7 – 2.2; vs. Left: 1.03 ml, IQR: 0.5 – 1.7; p<0.001); 4) there were no differences between the left and right ventricle with respect to stroke volume, cardiac output, or adjusted cardiac output; and 5) the left ventricular ejection fraction was greater than the right (Left: 72.2%, IQR: 64 – 78; vs. Right: 62.4%, IQR: 56 – 69; p<0.001). Conclusion Fetal echocardiography, utilizing STIC and VOCAL™ with the sub-feature: “Contour Finder: Trace”, allows assessment of fetal cardiovascular parameters. Normal fetal cardiovascular physiology is characterized by ventricular

  19. Quality of Anticoagulation Control in Preventing Adverse Events in Heart Failure Patients in Sinus Rhythm: A Warfarin Aspirin Reduced Cardiac Ejection Fraction Trial (WARCEF) Substudy

    PubMed Central

    Homma, Shunichi; Thompson, John L.P.; Qian, Min; Ye, Siqin; Di Tullio, Marco R.; Lip, Gregory Y.H.; Mann, Douglas L.; Sacco, Ralph L.; Levin, Bruce; Pullicino, Patrick M.; Freudenberger, Ronald S.; Teerlink, John R.; Graham, Susan; Mohr, J.P.; Labovitz, Arthur J.; Buchsbaum, Richard; Estol, Conrado J.; Lok, Dirk J.; Ponikowski, Piotr; Anker, Stefan D.

    2015-01-01

    Background The aim of this study is to examine the relationship between time in therapeutic range (TTR) and clinical outcomes in heart failure (HF) patients in sinus rhythm (SR) treated with warfarin. Methods and Results We used data from the Warfarin vs. Aspirin in Reduced Cardiac Ejection Fraction Trial (WARCEF) to assess the relationship of TTR with the WARCEF primary outcome (ischemic stroke, intracerebral hemorrhage, or death); with death alone; ischemic stroke alone; major hemorrhage alone; and net clinical benefit (primary outcome and major hemorrhage combined). Multivariable Cox models were used to examine how the event risk changed with TTR and to compare the high TTR, low TTR, and aspirin patients, with TTR being treated as a time-dependent covariate. 2,217 patients were included in the analyses, among whom 1,067 were randomized to warfarin and 1,150 were randomized to aspirin. The median (IQR) follow-up duration was 3.6 (2.0–5.0) years. Mean (±SD) age was 61±11.3 years, with 80% being men. The mean (±SD) TTR was 57% (±28.5%). Increasing TTR was significantly associated with reduction in primary outcome (adjusted p<0.001), death alone (adjusted p=0.001), and improved net clinical benefit (adjusted p<0.001). A similar trend was observed for the other two outcomes but significance was not reached (adjusted p=0.082 for ischemic stroke, adjusted p=0.109 for major hemorrhage). Conclusions In HF patients in SR, increasing TTR is associated with better outcome and improved net clinical benefit. Patients in whom good quality anticoagulation can be achieved may benefit from the use of anticoagulants. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00041938. PMID:25850425

  20. Speckle tracking determination of mitral tissue annular displacement: comparison with strain and ejection fraction, and association with outcomes in haemodialysis patients.

    PubMed

    Chiu, Diana Y Y; Abidin, Nik; Hughes, John; Sinha, Smeeta; Kalra, Philip A; Green, Darren

    2016-10-01

    Abnormal Global longitudinal strain (GLS) and reduced left ventricular ejection fraction (LVEF) are established poor prognostic risk factors in haemodialysis patients. Tissue motion annular displacement of mitral valve annulus (TMAD), determined by speckle tracking echocardiography (STE), can be performed rapidly and is an indicator of systolic dysfunction, but has been less well explored. This study aims to compare TMAD with GLS and LVEF and its association with outcomes in haemodialysis patients. 198 haemodialysis patients (median age 64.2 years, 69 % men) had 2D echocardiography, with STE determined GLS and TMAD. Bland-Altman analysis and linear regression assessed relationship between GLS, LVEF and TMAD. Cox regression analysis investigated association of TMAD with mortality and cardiac events. TMAD had low inter- and intra-observer variability with small biases and narrow limits of agreement (LOA) (bias of -0.01 ± 1.32 (95 % LOA was -2.60 to 2.58) and -0.07 ± 1.27 (95 % LOA -2.55 to 2.41) respectively). There was a moderate negative correlation between GLS and LVEF (r = -0.383, p < 0.001) and a weak positive correlation between TMAD and LVEF (r = 0.248, p < 0.001). There was strong negative correlation of TMAD with GLS (r = -0.614, p < 0.001). In a multivariable Cox regression analysis, TMAD was not associated with mortality (HR 1.04, 95 % CI 0.91-1.19), cardiac death (HR 1.03, 95 % CI 0.80-1.32) or cardiac events (HR 0.91, 95 % CI 0.80-1.02). TMAD is a quick and reproducible alternative to GLS which may be very useful in cardiovascular risk assessment, but does not have the same prognostic value in HD patients as GLS.

  1. A new Doppler method of assessing left ventricular ejection force in chronic congestive heart failure.

    PubMed

    Isaaz, K; Ethevenot, G; Admant, P; Brembilla, B; Pernot, C

    1989-07-01

    A noninvasive method using Doppler echocardiography was developed to determine the force exerted by the left ventricle in accelerating the blood into the aorta. The value of this new Doppler ejection index in the assessment of left ventricular (LV) performance was tested in 36 patients with chronic congestive heart disease undergoing cardiac catheterization and in 11 age-matched normal control subjects. The 36 patients were subgrouped into 3 groups based on angiographic ejection fraction (LV ejection fraction greater than 60, 41 to 60 and less than or equal to 40%). According to Newton's second law of motion (force = mass X acceleration), the LV ejection force was derived from the product of the mass of blood ejected during the acceleration time with the mean acceleration undergone during that time. In patients with LV ejection fraction less than or equal to 40%, LV ejection force, peak aortic velocity and mean acceleration were severely depressed when compared with the other groups (p less than 0.001). In patients with LV ejection fraction of 41 to 60%, LV ejection force was significantly reduced (22 +/- 3 kdynes) when compared with normal subjects (29 +/- 5 kdynes, p = 0.002) and with patients with LV ejection fraction greater than 60% (29 +/- 7 kdynes, p = 0.009); peak velocity and mean acceleration did not differ between these 3 groups. The LV ejection force showed a good linear correlation with LV ejection fraction (r = 0.86) and a better power fit (r = 0.91). Peak aortic blood velocity and mean acceleration showed less good linear correlations with LV ejection fraction (r = 0.73 and r = 0.66, respectively). The mass of blood ejected during the acceleration time also showed a weak linear correlation with LV ejection fraction (r = 0.64). An LV ejection force less than 20 kdynes was associated with a depressed LV performance (LV ejection fraction less than 50%) with 91% sensitivity and 90% specificity. Thus, these findings suggest that LV ejection force is a new

  2. Impact ejection of lunar meteorites and the age of Giordano Bruno

    NASA Astrophysics Data System (ADS)

    Fritz, Jörg

    2012-11-01

    Based on literature data from lunar meteorites and orbital observations it is argued that the lunar crater Giordano Bruno (22 km ∅) formed more than 1 Ma ago and probably ejected the lunar meteorites Yamato 82192/82193/86032 at 8.5 ± 1.5 Ma ago from the Th-poor highlands of the Moon. The efficiency and time scale to deliver 3He-rich lunar material into Earth’s sediments is discussed to assess the temporal relationship between the Giordano Bruno cratering event and a 1 Ma enduring 3He-spike which is observed in 8.2 Ma old sediments on Earth.

  3. Abnormal calcium homeostasis in heart failure with preserved ejection fraction is related to both reduced contractile function and incomplete relaxation: an electromechanically detailed biophysical modeling study

    PubMed Central

    Adeniran, Ismail; MacIver, David H.; Hancox, Jules C.; Zhang, Henggui

    2015-01-01

    Heart failure with preserved ejection fraction (HFpEF) accounts for about 50% of heart failure cases. It has features of incomplete relaxation and increased stiffness of the left ventricle. Studies from clinical electrophysiology and animal experiments have found that HFpEF is associated with impaired calcium homeostasis, ion channel remodeling and concentric left ventricle hypertrophy (LVH). However, it is still unclear how the abnormal calcium homeostasis, ion channel and structural remodeling affect the electro-mechanical dynamics of the ventricles. In this study we have developed multiscale models of the human left ventricle from single cells to the 3D organ, which take into consideration HFpEF-induced changes in calcium handling, ion channel remodeling and concentric LVH. Our simulation results suggest that at the cellular level, HFpEF reduces the systolic calcium level resulting in a reduced systolic contractile force, but elevates the diastolic calcium level resulting in an abnormal residual diastolic force. In our simulations, these abnormal electro-mechanical features of the ventricular cells became more pronounced with the increase of the heart rate. However, at the 3D organ level, the ejection fraction of the left ventricle was maintained due to the concentric LVH. The simulation results of this study mirror clinically observed features of HFpEF and provide new insights toward the understanding of the cellular bases of impaired cardiac electromechanical functions in heart failure. PMID:25852567

  4. A novel paradigm for heart failure with preserved ejection fraction: comorbidities drive myocardial dysfunction and remodeling through coronary microvascular endothelial inflammation.

    PubMed

    Paulus, Walter J; Tschöpe, Carsten

    2013-07-23

    Over the past decade, myocardial structure, cardiomyocyte function, and intramyocardial signaling were shown to be specifically altered in heart failure with preserved ejection fraction (HFPEF). A new paradigm for HFPEF development is therefore proposed, which identifies a systemic proinflammatory state induced by comorbidities as the cause of myocardial structural and functional alterations. The new paradigm presumes the following sequence of events in HFPEF: 1) a high prevalence of comorbidities such as overweight/obesity, diabetes mellitus, chronic obstructive pulmonary disease, and salt-sensitive hypertension induce a systemic proinflammatory state; 2) a systemic proinflammatory state causes coronary microvascular endothelial inflammation; 3) coronary microvascular endothelial inflammation reduces nitric oxide bioavailability, cyclic guanosine monophosphate content, and protein kinase G (PKG) activity in adjacent cardiomyocytes; 4) low PKG activity favors hypertrophy development and increases resting tension because of hypophosphorylation of titin; and 5) both stiff cardiomyocytes and interstitial fibrosis contribute to high diastolic left ventricular (LV) stiffness and heart failure development. The new HFPEF paradigm shifts emphasis from LV afterload excess to coronary microvascular inflammation. This shift is supported by a favorable Laplace relationship in concentric LV hypertrophy and by all cardiac chambers showing similar remodeling and dysfunction. Myocardial remodeling in HFPEF differs from heart failure with reduced ejection fraction, in which remodeling is driven by loss of cardiomyocytes. The new HFPEF paradigm proposes comorbidities, plasma markers of inflammation, or vascular hyperemic responses to be included in diagnostic algorithms and aims at restoring myocardial PKG activity.

  5. High-intensity interval training vs. moderate-intensity continuous exercise training in heart failure with preserved ejection fraction: a pilot study.

    PubMed

    Angadi, Siddhartha S; Mookadam, Farouk; Lee, Chong D; Tucker, Wesley J; Haykowsky, Mark J; Gaesser, Glenn A

    2015-09-15

    Heart failure with preserved ejection fraction (HFpEF) is a major cause of morbidity and mortality. Exercise training is an established adjuvant therapy in heart failure; however, the effects of high-intensity interval training (HIIT) in HFpEF are unknown. We compared the effects of HIIT vs. moderate-intensity aerobic continuous training (MI-ACT) on peak oxygen uptake (V̇o₂peak), left ventricular diastolic dysfunction, and endothelial function in patients with HFpEF. Nineteen patients with HFpEF (age 70 ± 8.3 yr) were randomized to either HIIT (4 × 4 min at 85-90% peak heart rate, with 3 min active recovery) or MI-ACT (30 min at 70% peak heart rate). Fifteen patients completed exercise training (HIIT: n = 9; MI-ACT: n = 6). Patients trained 3 days/wk for 4 wk. Before and after training patients underwent a treadmill test for V̇o₂peak determination, 2D-echocardiography for assessment of left ventricular diastolic dysfunction, and brachial artery flow-mediated dilation (FMD) for assessment of endothelial function. HIIT improved V̇o₂peak (pre = 19.2 ± 5.2 ml·kg(-1)·min(-1); post = 21.0 ± 5.2 ml·kg(-1)·min(-1); P = 0.04) and left ventricular diastolic dysfunction grade (pre = 2.1 ± 0.3; post = 1.3 ± 0.7; P = 0.02), but FMD was unchanged (pre = 6.9 ± 3.7%; post = 7.0 ± 4.2%). No changes were observed following MI-ACT. A trend for reduced left atrial volume index was observed following HIIT compared with MI-ACT (-3.3 ± 6.6 vs. +5.8 ± 10.7 ml/m(2); P = 0.06). In HFpEF patients 4 wk of HIIT significantly improved V̇o₂peak and left ventricular diastolic dysfunction. HIIT may provide a more robust stimulus than MI-ACT for early exercise training adaptations in HFpEF.

  6. Ghrelin and hormonal markers under exercise training in patients with heart failure with preserved ejection fraction: results from the Ex‐DHF pilot study

    PubMed Central

    Trippel, Tobias Daniel; Holzendorf, Volker; Halle, Martin; Gelbrich, Götz; Nolte, Kathleen; Duvinage, Andre; Schwarz, Silja; Rutscher, Tinka; Wiora, Julian; Wachter, Rolf; Herrmann‐Lingen, Christoph; Duengen, Hans‐Dirk; Hasenfuß, Gerd; Pieske, Burkert

    2016-01-01

    Abstract Background Over 50% of patients with symptomatic heart failure (HF) experience HF with preserved ejection fraction (HFpEF). Exercise training (ET) is effective in improving cardiorespiratory fitness and dimensions of quality of life in patients with HFpEF. A systemic pro‐inflammatory state induced by comorbidities as the cause of myocardial structural and functional alterations has been proposed in HFpEF. ET modifies myocardial structure and has been related to inflammatory state. We investigated Ghrelin, related adipokines, markers of inflammation, and neuro‐hormonal activation in patients undergoing a structured ET vs. usual care are with HFpEF. Methods and results Ex‐DHF‐P was a prospective, controlled, randomized multi‐centre trial on structured and supervised ET in patients with HFpEF. We performed a post hoc analysis in 62 patients from Ex‐DHF‐P. Ghrelin, adiponectin, leptin, IL‐1ß, IL‐6, IL‐10, tumour necrosis factor‐alpha, MR‐proANP, MR‐proADM, CT‐proET1, and CT‐proAVP were assessed to seize the impact of ET on these markers in patients with HFpEF. Thirty‐six (58%) patients were female, mean age was 64 years, and median ghrelin was 928 pg/mL (interquartile range 755–1156). When stratified for high versus low ghrelin, groups significantly differed at baseline in presence obesity, waist circumference, and adiponectin levels (P < 0.05, respectively). Overall, ghrelin levels rose significantly to 1013 pg/mL (interquartile range 813–1182) (P < 0.001). Analysis of covariance modelling for change in ghrelin identified ET (P = 0.013) and higher baseline adiponectin levels (P = 0.035) as influencing factors. Conclusions Exercise training tended to increase ghrelin levels in Ex‐DHF‐P. This increase was especially pronounced in patients with higher baseline adiponectin levels. Future trials are needed to investigate the effect of ET on endogenous ghrelin levels in regard to interactions with

  7. Influence of silanization and filler fraction on aged dental composites.

    PubMed

    Lin, C T; Lee, S Y; Keh, E S; Dong, D R; Huang, H M; Shih, Y H

    2000-11-01

    The effect of silanization and filler fraction on the mechanical properties of aged dental composites was investigated. Experimental composites (75/25 Bis-GMA/TEGDMA resin reinforced with 0, 12.6, 30.0, and 56.5 vol% 8 microm silanized/unsilanized BaSiO6) were fabricated into 4.7 mm diameter x 2.2 mm thick discs and 3.5 mm diameter x 7.3 mm thick discs for diametral tensile and compressive tests, respectively. The effect of immersion in 75% ethanol at 37 degrees C for 0-30 days on the diametral tensile strength (DTS) and compressive strength (CS) of the samples was evaluated and analysed by ANOVA and Tukey LSD test. The fracture interface between filler and resin matrix was then examined by scanning electron microscope. Results and subsequent statistical evidence from DTS (18.6+/-7.6 MPa, silanized versus 11.7+/-2.6 MPa, unsilanized) and CS (85.1+/-29.7 MPa, silanized versus 56.0+/-11.3 MPa, unsilanized) strongly implies that silanization may greatly enhance the mechanical properties of the resin composites. Furthermore, it also shows that both DTS and CS increased proportionally as the filler fraction of the composites increased. However, in the unsilanized groups, DTS decreased (up to 40%) as the filler fraction increased, and CS showed no relevance to the filler fraction at all. As for the influence of aging, it was found that both DTS and CS showed a significant decrease after immersion in 75% ethanol, and silanization heavily correlated with the filler fraction of aged-resin composites. Microscopic examination of the fractured samples showed that failure primarily occurred within the resin matrix per se for silanized composites and adjacent to the filler particles for unsilanized composites. All the evidence points to the conclusion that mechanical properties of aged-resin composites can be greatly influenced by silanization and the filler fraction.

  8. Combination of high-sensitivity troponin I and N-terminal pro-B-type natriuretic peptide predicts future hospital admission for heart failure in high-risk hypertensive patients with preserved left ventricular ejection fraction.

    PubMed

    Okuyama, Ryunosuke; Ishii, Junnichi; Takahashi, Hiroshi; Kawai, Hideki; Muramatsu, Takashi; Harada, Masahide; Yamada, Akira; Motoyama, Sadako; Matsui, Shigeru; Naruse, Hiroyuki; Sarai, Masayoshi; Hasegawa, Midori; Watanabe, Eiichi; Suzuki, Atsushi; Hayashi, Mutsuharu; Izawa, Hideo; Yuzawa, Yukio; Ozaki, Yukio

    2017-02-02

    Additional risk stratification may provide more aggressive and focalized preventive treatment to high-risk hypertensive patients according to the Japanese hypertension guidelines. We prospectively investigated the predictive value of high-sensitivity troponin I (hsTnI), both independently and in combination with N-terminal pro-B-type natriuretic peptide (NT-proBNP), for incident heart failure (HF) in high-risk hypertensive patients with preserved left ventricular ejection fraction (LVEF). Baseline hsTnI and NT-proBNP levels and echocardiography data were obtained for 493 Japanese hypertensive outpatients (mean age, 68.5 years) with LVEF ≥ 50%, no symptomatic HF, and at least one of the following comorbidities: stage 3-4 chronic kidney disease, diabetes mellitus, and stable coronary artery disease. During a mean follow-up period of 86.1 months, 44 HF admissions occurred, including 31 for HF with preserved ejection fraction (HFpEF) and 13 for HF with reduced ejection fraction (HFrEF; LVEF <50%). Both hsTnI (p < 0.01) and NT-proBNP (p < 0.005) levels were significant independent predictors of HF admission. Furthermore, when the patients were stratified into 4 groups according to increased hsTnI (≥highest tertile value of 10.6 pg/ml) and/or increased NT-proBNP (≥highest tertile value of 239.7 pg/ml), the adjusted relative risks for patients with increased levels of both biomarkers versus neither biomarker were 13.5 for HF admission (p < 0.0001), 9.45 for HFpEF (p = 0.0009), and 23.2 for HFrEF (p = 0.003). Finally, the combined use of hsTnI and NT-proBNP enhanced the C-index (p < 0.05), net reclassification improvement (p = 0.0001), and integrated discrimination improvement (p < 0.05) to a greater extent than that of any single biomarker. The combination of hsTnI and NT-proBNP, which are individually independently predictive of HF admission, could improve predictions of incident HF in high-risk hypertensive patients but could

  9. Circulating Fibroblast Growth Factor 21 is Associated with Diastolic Dysfunction in Heart Failure Patients with Preserved Ejection Fraction

    PubMed Central

    Chou, Ruey-Hsing; Huang, Po-Hsun; Hsu, Chien-Yi; Chang, Chun-Chin; Leu, Hsin-Bang; Huang, Chin-Chou; Chen, Jaw-Wen; Lin, Shing-Jong

    2016-01-01

    Fibroblast growth factor 21 (FGF21), a polypeptide ligand promoted glucose homeostasis and lipids metabolism, was recently reported to attenuate cardiac hypertrophy. The aim of this study was to investigate the impact of FGF21 in diastolic heart failure. Subjects admitted for coronary angiogram were screened for heart failure, and those with left ventricular (LV) ejection fraction < 45% were excluded. Diastolic dysfunction was defined as functional abnormalities that exist during LV relaxation and filling by echocardiographic criteria. Plasma levels of FGF21 and N-terminal Pro-Brain Natriuretic Peptide (NT-pro-BNP) were determined. All patients were followed up for 1 year, or till the occurrence of heart failure readmission or death. Totally 95 patients with diastolic dysfunction and 143 controls were enrolled. Circulating FGF21 level was correlated with echocardiographic parameters of diastolic function and LV end-diastolic pressure (LVEDP). In multivariate logistic analysis, FGF21 was significantly associated with diastolic dysfunction, either identified by echocardiographic criteria (odds ratio: 2.97, p = 0.012) or confirmed with LVEDP level (odds ratio: 3.73, p = 0.030). Both plasma FGF21 (log rank p < 0.0001) and NT-pro-BNP levels (log rank p = 0.0057) showed good predictive power to the 1-year adverse cardiac events. This finding suggested FGF21 could be involved in the pathophysiology of diastolic heart failure. PMID:27650781

  10. Bleeding Risk and Antithrombotic Strategy in Patients with Sinus Rhythm Heart Failure with Reduced Ejection Fraction Treated with Warfarin or Aspirin

    PubMed Central

    Ye, Siqin; Cheng, Bin; Lip, Gregory Y. H.; Buchsbaum, Richard; Sacco, Ralph L.; Levin, Bruce; Di Tullio, Marco R.; Qian, Min; Mann, Douglas L.; Pullicino, Patrick M.; Freudenberger, Ronald S.; Teerlink, John R.; Mohr, J.P.; Graham, Susan; Labovitz, Arthur J.; Estol, Conrado J.; Lok, Dirk J.; Ponikowski, Piotr; Anker, Stefan D.; Thompson, John L.P.; Homma, Shunichi

    2015-01-01

    We sought to assess the performance of existing bleeding risk scores, such as HAS-BLED or OBRI, in patients with heart failure with reduced ejection fraction (HFrEF) in sinus rhythm (SR) treated with warfarin or aspirin. We calculated HAS-BLED and OBRI risk scores for 2,305 patients with HFrEF in SR enrolled in the Warfarin versus Aspirin in Reduced Cardiac Ejection Fraction (WARCEF) trial. Proportional hazards models were used to test whether each score predicted major bleeding, and comparison of different risk scores was performed using Harell’s c-statistic and net-reclassification improvement (NRI) index. For the warfarin arm, both scores predicted bleeding risk, with OBRI having significantly higher c-statistic (0.72 vs 0.61; p=0.03) compared to HAS-BLED, though the NRI for comparing OBRI to HAS-BLED was not significant (0.32, 95% CI - 0.18-0.37). Performance of the OBRI and HAS-BLED risk scores were similar for the aspirin arm. For participants with OBRI score of 0 to 1, warfarin compared with aspirin reduced ischemic stroke (HR 0.51, 95% CI 0.26-0.98, p=0.042) without significantly increasing major bleeding (HR 1.24, 95% CI 0.66-2.30, p=0.51). For those with OBRI score of ≥2, there was a trend for reduced ischemic stroke with warfarin compared to aspirin (HR 0.56, 95% CI 0.27-1.15, p=0.12), but major bleeding was increased (HR 4.04, 95% CI 1.99-8.22, p<0.001). In conclusion, existing bleeding risk scores can identify bleeding risk in HFrEF patients in SR, and could be tested for potentially identifying patients with a favorable risk / benefit profile for antithrombotic therapy with warfarin. PMID:26189039

  11. Clinical Effectiveness of Hydralazine-Isosorbide Dinitrate Therapy in Patients With Heart Failure and Reduced Ejection Fraction: Findings From the GWTG-HF Registry

    PubMed Central

    Khazanie, Prateeti; Liang, Li; Curtis, Lesley H.; Butler, Javed; Eapen, Zubin J.; Heidenreich, Paul A.; Bhatt, Deepak L.; Peterson, Eric D.; Yancy, Clyde W.; Fonarow, Gregg C.; Hernandez, Adrian F.

    2016-01-01

    Background In clinical trials, hydralazine-isosorbide dinitrate (H-ISDN) for heart failure with reduced ejection fraction reduced morbidity and mortality among black patients and patients with intolerance to angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs). The effectiveness of H-ISDN in clinical practice is unknown. Methods and Results Using data from a clinical registry linked with Medicare claims, we examined the use and outcomes of H-ISDN between 2005 and 2011 among older patients hospitalized with heart failure and reduced ejection fraction. We adjusted for demographic and clinical characteristics using Cox proportional hazards models and inverse probability weighting. Among 4663 eligible patients, 22.7% of black patients and 18.2% of patients not on an ACE inhibitor or ARB were newly prescribed H-ISDN therapy at discharge. By 3 years, the cumulative incidence rates of mortality and readmission were similar between treated and untreated patients. After multivariable adjustment, 3-year outcomes remained similar for mortality (black patients: hazard ratio [HR], 0.92; 95% CI, 0.75–1.13; other patients: HR, 0.93; 95% CI, 0.79–1.09), all-cause readmission (black patients: HR, 0.98; 95% CI, 0.84–1.13; other patients: HR, 1.02; 95% CI, 0.90–1.17), and cardiovascular readmission (black patients: HR, 0.99; 95% CI, 0.82–1.19; other patients: HR, 0.94; 95% CI, 0.81–1.09). A post hoc analysis of Medicare Part D data revealed low postdischarge adherence to therapy. Conclusions Guideline-recommended initiation of H-ISDN therapy at hospital discharge was uncommon and adherence was low. For both black patients and patients of other races, there were no differences in outcomes between those treated and untreated at discharge. PMID:26867758

  12. Prognostic usefulness of insulin-like growth factor-binding protein 7 in heart failure with reduced ejection fraction: a novel biomarker of myocardial diastolic function?

    PubMed

    Gandhi, Parul U; Gaggin, Hanna K; Sheftel, Alex D; Belcher, Arianna M; Weiner, Rory B; Baggish, Aaron L; Motiwala, Shweta R; Liu, Peter P; Januzzi, James L

    2014-11-15

    Insulin-like growth factor-binding protein 7 (IGFBP7) is a biomarker that has recently been associated with heart failure and cardiac hypertrophy. The aim of this study was to examine IGFBP7 relative to echocardiographic abnormalities reflecting diastolic dysfunction. One hundred twenty-four patients with ambulatory heart failure with reduced ejection fraction and baseline detailed 2-dimensional echocardiograms were followed for a mean of 10 months. IGFBP7 was measured serially at each office visit; 108 patients underwent follow-up echocardiography. Echocardiographic parameters of diastolic function were compared at baseline and over time. IGFBP7 concentrations were not linked to left ventricular size or systolic function. In contrast, those with elevated baseline IGFBP7 concentrations were more likely to have abnormalities of parameters describing diastolic function, such as higher left atrial volume index, transmitral E/A ratio, E/E' ratio, and right ventricular systolic pressure. IGFBP7 was correlated with left atrial volume index (ρ = 0.237, p = 0.008), transmitral E/A ratio (ρ = 0.304, p = 0.001), E/E' ratio (ρ = 0.257, p = 0.005), and right ventricular systolic pressure (ρ = 0.316, p = 0.001). Furthermore, each was found to be independently predictive of IGFBP7 in adjusted analysis. In subjects with baseline and final echocardiograms, more time spent with elevated IGFBP7 concentrations in serial measurement was associated with worsening diastolic function and increasing left atrial volume index or right ventricular systolic pressure. IGFBP7 concentrations were predictive of an increased risk for cardiovascular events independent of echocardiographic measures of diastolic function (p = 0.006). In conclusion, IGFBP7 is a novel prognostic biomarker for heart failure with reduced ejection fraction and shows significant links to the presence and severity of echocardiographic parameters of abnormal diastolic function.

  13. Insuffisance cardiaque à fraction d'ejection preservee en afrique sub-saharienne: à propos de 32 cas

    PubMed Central

    Mboup, Mouhamed Cherif; Dia, Khadidiatou; Fall, Pape Diadie

    2013-01-01

    L'insuffisance cardiaque à fraction d’éjection préservée est une affection de plus en plus fréquente dont le diagnostic est difficile car elle prédomine chez les sujets âgés présentant d'autres pathologies. Le but de ce travait était d’évaluer les aspects épidémiologiques, cliniques, paracliniques et thérapeutiques de cette affection en milieu hospitalier. Il s'agit d'une étude prospective, descriptive réalisé au niveau du service de cardiologie de l'hôpital principal de Dakar sur une période de 01 an (01 février 2008 - 31 janvier 2009). Le diagnostic d'insuffisance cardiaque avait été retenu chez 111 patients. Au sein de ce groupe de patient, l’échodoppler cardiaque mettait en évidence une dysfonction diastolique isolée du ventricule gauche dans 32 cas (28,8%). L’âge moyen des patients était de 65,7 ± 9,1 ans. On notait une prédominance féminine avec sex ratio à 1,28 (18 femmes / 14 hommes). Une hypertension artérielle était retrouvée chez tous les patients. L’électrocardiogramme inscrivait une hypertrophie ventriculaire gauche et une fibrillation auriculaire chez respectivement 21 (65%) 4 patients (13%). L’échodoppler cardiaque trans-thoracique mettait en évidence une hypertrophie ventriculaire gauche et une dilatation de l'oreillette gauche chez respectivement 18 (56%) et 24 patients (75%). Le flux mitral était pseudonormal, restrictif, ou de type trouble de la relaxation chez respectivement 13 (41%), 10 (31%) et 9 (28%) patients. L'insuffisance cardiaque à fraction d’éjection préservée est caractérisée dans nos régions par la précocité de sa survenue et la présence chez tous les patients d'un long passé d'hypertension artérielle non équilibrée. PMID:24772229

  14. Left Atrial Function Predicts Heart Failure Hospitalization in Subjects with Preserved Ejection Fraction and Coronary Heart Disease: Longitudinal Data from the Heart and Soul Study

    PubMed Central

    Welles, Christine C.; Ku, Ivy A.; Kwan, Damon M.; Whooley, Mary A.; Schiller, Nelson B.; Turakhia, Mintu P.

    2012-01-01

    Objectives We sought to determine whether left atrial (LA) dysfunction predicts heart failure (HF) hospitalization in subjects with preserved baseline ejection fraction (EF). Background Among patients with preserved EF, factors leading to HF are not fully understood. Cross-sectional studies have demonstrated LA dysfunction at the time of HF, but longitudinal data on antecedent atrial function are lacking. Methods We performed resting transthoracic echocardiography in 855 subjects with coronary heart disease and EF≥50%. Left atrial functional index (LAFI) was calculated as [(LA emptying fraction × left ventricular outflow tract-velocity time integral)/(indexed LA end systolic volume)], where LA emptying fraction was defined as (LA end systolic volume - LA end diastolic volume)/LA end systolic volume. We used Cox models to evaluate the association between LAFI and HF hospitalization. Results Over a median follow-up of 7.9 years, 106 participants (12.4%) were hospitalized for HF. Rates of HF hospitalization were inversely proportional to quartile of LAFI: Q1: 47 per 1000 person-years; Q2: 18.3; Q3: 9.6; and Q4: 5.3 (p<0.001). Each standard deviation decrease in LAFI was associated with a 2.6-fold increased hazard of adverse cardiovascular outcomes (unadjusted HR: 2.6, 95% CI 2.1–3.3, p<0.001), and the association persisted even after adjustment for clinical risk factors, NT-proBNP, and a wide range of echocardiographic parameters (adjusted HR: 1.5, 95% CI 1.0–2.1, p=0.05). Conclusions LA dysfunction independently predicts HF hospitalization in subjects with coronary heart disease and preserved baseline EF. LAFI may be useful for HF risk stratification, and LA dysfunction may be a potential therapeutic target. PMID:22322084

  15. Fractional Dynamics of Network Growth Constrained by Aging Node Interactions

    PubMed Central

    Safdari, Hadiseh; Zare Kamali, Milad; Shirazi, Amirhossein; Khalighi, Moein; Jafari, Gholamreza; Ausloos, Marcel

    2016-01-01

    In many social complex systems, in which agents are linked by non-linear interactions, the history of events strongly influences the whole network dynamics. However, a class of “commonly accepted beliefs” seems rarely studied. In this paper, we examine how the growth process of a (social) network is influenced by past circumstances. In order to tackle this cause, we simply modify the well known preferential attachment mechanism by imposing a time dependent kernel function in the network evolution equation. This approach leads to a fractional order Barabási-Albert (BA) differential equation, generalizing the BA model. Our results show that, with passing time, an aging process is observed for the network dynamics. The aging process leads to a decay for the node degree values, thereby creating an opposing process to the preferential attachment mechanism. On one hand, based on the preferential attachment mechanism, nodes with a high degree are more likely to absorb links; but, on the other hand, a node’s age has a reduced chance for new connections. This competitive scenario allows an increased chance for younger members to become a hub. Simulations of such a network growth with aging constraint confirm the results found from solving the fractional BA equation. We also report, as an exemplary application, an investigation of the collaboration network between Hollywood movie actors. It is undubiously shown that a decay in the dynamics of their collaboration rate is found, even including a sex difference. Such findings suggest a widely universal application of the so generalized BA model. PMID:27171424

  16. Two-slope ascending arm of the early trans-mitral flow velocity Doppler wave in patients with heart failure and preserved ejection fraction.

    PubMed

    Dori, Guy; Egbaria, Muhammad A; Jabaren, Mohamed

    2014-12-01

    Trans-mitral flow velocity (TMFV) examination is a standard echocardiographic measure for assessing diastolic function of the heart. Typically, the Doppler signal representing the early rapid filling phase of the left ventricle (LV), termed: E wave, is triangular. The ascending arm of the E wave (EWAA) represents blood accelerating into the LV from the left atrium (LA), whereas the descending arm reflects blood decelerating as the LV fills and resists further filling. The slope of EWAA is linear, starting at TMFV of zero cm/s (prior to mitral valve opening) and building to peak E wave value. The physical meaning of a single slope is that blood acceleration is constant with time. Little data exist regarding the significance of the shape of EWAA. It is hypothesized that in heart failure with preserved ejection fraction (HFPEF) the EWAA displays 2 slopes. A first steeper slope followed by a second less steep slope reaching peak E wave. The different slopes represent a change in the composition of driving forces propelling blood from LA to LV. It is hypothesized that the first steeper slope of EWAA represents a set of driving force including a force termed: diastolic suction, whereas in the second slope diastolic suction has already dissipated. This 2-slope phenomenon is not expected in healthy subjects because the assumed underlying mechanism is not operative.

  17. Inspiratory Muscle Training and Functional Electrical Stimulation for Treatment of Heart Failure With Preserved Ejection Fraction: Rationale and Study Design of a Prospective Randomized Controlled Trial.

    PubMed

    Palau, Patricia; Domínguez, Eloy; López, Laura; Heredia, Raquel; González, Jessika; Ramón, Jose María; Serra, Pilar; Santas, Enrique; Bodi, Vicente; Sanchis, Juan; Chorro, Francisco J; Núñez, Julio

    2016-08-01

    Heart failure with preserved ejection fraction (HFpEF) has become the most prevalent form of heart failure in developed countries. Regrettably, there is no evidence-based effective therapy for HFpEF. We seek to evaluate whether inspiratory muscle training, functional electrical stimulation, or a combination of both can improve exercise capacity as well as left ventricular diastolic function, biomarker profile, quality of life (QoL), and prognosis in patients with HFpEF. A total of 60 stable symptomatic patients with HFpEF (New York Heart Association class II-III/IV) will be randomized (1:1:1:1) to receive a 12-week program of inspiratory muscle training, functional electrical stimulation, a combination of both, or standard care alone. The primary endpoint of the study is change in peak exercise oxygen uptake; secondary endpoints are changes in QoL, echocardiogram parameters, and prognostic biomarkers. As of March 21, 2016, thirty patients have been enrolled. Searching for novel therapies that improve QoL and autonomy in the elderly with HFpEF has become a health care priority. We believe that this study will add important knowledge about the potential utility of 2 simple and feasible physical interventions for the treatment of advanced HFpEF.

  18. The effects of wenxin keli on left ventricular ejection fraction and brain natriuretic Peptide in patients with heart failure: a meta-analysis of randomized controlled trials.

    PubMed

    Chen, Yu; Xiong, Xingjiang; Wang, Chunmei; Wang, Chenggang; Zhang, Ying; Zhang, Xingyong; Gao, Yonghong; Xing, Yanhui; Li, Jun; Wang, Jie; Liu, Xiaoqiu; Xing, Yanwei

    2014-01-01

    Objective. To evaluate the beneficial and adverse effects of Wenxin Keli (WXKL), either alone or in combination with Western medicine, on the left ventricular ejection fraction (LVEF) and plasma brain natriuretic peptide (BNP) in the treatment of heart failure (HF). Methods. Seven major electronic databases were searched to retrieve potential randomized controlled trials (RCTs) designed to evaluate the clinical effectiveness of WXKL, either alone or in combination with Western medicine, for HF, with the LVEF or BNP after eight weeks of treatment as main outcome measures. The methodological quality of the included studies was assessed using criteria from the Cochrane Handbook for Systematic Review of Interventions, Version 5.1.0, and analyzed using RevMan 5.1.0 software. Results. Eleven RCTs of WXKL were included. The methodological quality of the trials was generally evaluated as low. The risk of bias was high. The results of the meta-analysis showed that WXKL, either alone or in combination with Western medicine, was more effective in LVEF and BNP, compared with no medicine or Western medicine alone, in patients with HF or HF complicated by other diseases. Five of the trials reported adverse events, while the others did not mention them, indicating that the safety of WXKL remains uncertain. Conclusions. WXKL, either alone or in combination with Western medicine, appears to be more effective in improving the LVEF and BNP in patients with HF and HF complications.

  19. The Effects of Wenxin Keli on Left Ventricular Ejection Fraction and Brain Natriuretic Peptide in Patients with Heart Failure: A Meta-Analysis of Randomized Controlled Trials

    PubMed Central

    Chen, Yu; Xiong, Xingjiang; Wang, Chunmei; Wang, Chenggang; Zhang, Ying; Zhang, Xingyong; Gao, Yonghong; Xing, Yanhui; Li, Jun; Wang, Jie; Liu, Xiaoqiu; Xing, Yanwei

    2014-01-01

    Objective. To evaluate the beneficial and adverse effects of Wenxin Keli (WXKL), either alone or in combination with Western medicine, on the left ventricular ejection fraction (LVEF) and plasma brain natriuretic peptide (BNP) in the treatment of heart failure (HF). Methods. Seven major electronic databases were searched to retrieve potential randomized controlled trials (RCTs) designed to evaluate the clinical effectiveness of WXKL, either alone or in combination with Western medicine, for HF, with the LVEF or BNP after eight weeks of treatment as main outcome measures. The methodological quality of the included studies was assessed using criteria from the Cochrane Handbook for Systematic Review of Interventions, Version 5.1.0, and analyzed using RevMan 5.1.0 software. Results. Eleven RCTs of WXKL were included. The methodological quality of the trials was generally evaluated as low. The risk of bias was high. The results of the meta-analysis showed that WXKL, either alone or in combination with Western medicine, was more effective in LVEF and BNP, compared with no medicine or Western medicine alone, in patients with HF or HF complicated by other diseases. Five of the trials reported adverse events, while the others did not mention them, indicating that the safety of WXKL remains uncertain. Conclusions. WXKL, either alone or in combination with Western medicine, appears to be more effective in improving the LVEF and BNP in patients with HF and HF complications. PMID:24868236

  20. In situ expression of Bcl-2 in pulmonary artery endothelial cells associates with pulmonary arterial hypertension relative to heart failure with preserved ejection fraction

    PubMed Central

    Benza, Raymond L.; Williams, Gretchen; Wu, Changgong; Shields, Kelly J.; Raina, Amresh; Murali, Srinivas

    2016-01-01

    Abstract We have previously reported that pulmonary artery endothelial cells (PAECs) can be harvested from the tips of discarded Swan-Ganz catheters after right heart catheterization (RHC). In this study, we tested the hypothesis that the existence of an antiapoptotic phenotype in PAECs obtained during RHC is a distinctive feature of pulmonary arterial hypertension (PAH; World Health Organization group 1) and might be used to differentiate PAH from other etiologies of pulmonary hypertension. Specifically, we developed a flow cytometry-based measure of Bcl-2 activity, referred to as the normalized endothelial Bcl-2 index (NEBI). We report that higher NEBI values are associated with PAH to the exclusion of heart failure with preserved ejection fraction (HFpEF) and that this simple diagnostic measurement is capable of differentiating PAH from HFpEF without presenting addition risk to the patient. If validated in a larger, multicenter study, the NEBI has the potential to assist physicians in the selection of appropriate therapeutic interventions in the common and dangerous scenario wherein patients present a clinical and hemodynamic phenotype that makes it difficult to confidently differentiate between PAH and HFpEF. PMID:28090298

  1. Prognostic Significance of Active and Modified forms of Endothelin 1 in Patients with Heart Failure with Reduced Ejection Fraction

    PubMed Central

    Gottlieb, Stephen S.; Harris, Kristie; Todd, John; Estis, Joel; Christenson, Robert H.; Torres, Victoria; Whittaker, Kerry; Rebuck, Heather; Wawrzyniak, Andrew; Krantz, David S.

    2015-01-01

    Objectives Concentrations of endothelin I (ET1) are elevated in CHF patients, and, like other biomarkers that reflect hemodynamic status and cardiac pathophysiology, are prognostic. The Singulex assay (Sgx-ET1) measures the active form of ET1, with a short in-vivo half-life and C-terminal endothelin-1 (CT-ET1) is measured by the Brahms assay and is a modified (degraded) product with longer half-life. We aimed to determine the prognostic importance of active and modified forms of endothelin 1 (Singulex and Brahms assays) in comparison with other commonly measured biomarkers of inflammation, hemodynamic status and cardiac physiology in CHF. Design & Methods Plasma biomarkers (Sgx-ET1, CT-ET1, NTproBNP, IL-6, TNFα, cTnI, VEGF, hs-CRP, Galectin-3, ST2) were measured in 134 NYHA class II and III CHF patients with systolic dysfunction. Prognostic importance of biomarkers for hospitalization or death were calculated by both logistic regression and Kaplan-Meier survival analyses. Results CT-ET1 (OR 5.2, 95% CI 1.7–15.7) and Sgx-ET1 (OR 2.9, CI 1.1–7.7) were independent predictors of hospitalization and death and additively predicted events after adjusting for age, sex and other significant biomarkers. Other biomarkers did not improve the model. Similarly, in Cox regression analysis, only CT-ET1 (HR 3.4, 95% CI 1.4–8.4), VEGF (2.7, 95% CI 1.3–5.4) and Sgx-ET1 (HR 2.6, 95% CI 1.2–5.6) were independently prognostic. Conclusions Elevated concentrations of endothelin 1 predict mortality and hospitalizations in HF patients. Endothelin 1 was more prognostic than commonly obtained hemodynamic, inflammatory and fibrotic biomarkers. Two different assays of endothelin 1 independently and synergistically were prognostic, suggesting either complementary information or extreme prognostic importance. PMID:25541019

  2. Analysis of circumferential and longitudinal left ventricular systolic function in patients with non-ischemic chronic heart failure and preserved ejection fraction (from the CARRY-IN-HFpEF study).

    PubMed

    Cioffi, Giovanni; Senni, Michele; Tarantini, Luigi; Faggiano, Pompilio; Rossi, Andrea; Stefenelli, Carlo; Russo, Tiziano Edoardo; Alessandro, Selmi; Furlanello, Francesco; de Simone, Giovanni

    2012-02-01

    Heart failure with preserved left ventricular ejection fraction (HFpEF) is implicitly attributed to diastolic dysfunction, often recognized in elderly patients with hypertension, diabetes, and renal dysfunction. In these patients, left ventricular circumferential and longitudinal shortening is often impaired despite normal ejection fraction. The aim of this prospective study was to analyze circumferential and longitudinal shortening and their relations in patients with nonischemic HFpEF. Stress-corrected midwall shortening (sc-MS) and mitral annular peak systolic velocity (S') were measured in 60 patients (mean age 73 ± 13 years) with chronic nonischemic HFpEF in stable New York Heart Association functional class II or III and compared to the values in 120 healthy controls and 120 patients with hypertension without HFpEF. Sc-MS was classified as low if <89% and S' as low if <8.5 cm/s (the 10th-percentile values of healthy controls). Isolated low sc-MS was detected in 46% of patients with HFpEF, 27% of patients with hypertension, and 2% of controls; isolated low S' was detected in 11% of patients with HFpEF, 7% of patients with hypertension, and 5% of controls; and combined low sc-MS and low S' was detected in 26% of patients with HFpEF, 9% of patients with hypertension, and 5% of controls (HFpEF vs others, all p values <0.001). Thus, any alteration of systolic function was found in 83% of patients with HFpEF. The relation between sc-MS and S' was nonlinear (cubic). Changes in S' within normal values corresponded to negligible variations in sc-MS, whereas the progressive decrease below 8.5 cm/s was associated with substantial decrease in sc-MS. In conclusion, circumferential and/or longitudinal systolic dysfunction is present in most patients with HFpEF. Circumferential shortening normalized by wall stress identifies more patients with concealed left ventricular systolic dysfunction than longitudinal shortening.

  3. Changes in Follow-up Left Ventricular Ejection Fraction Associated with Outcomes in Primary Prevention ICD and CRT-D Recipients

    PubMed Central

    Zhang, Yiyi; Guallar, Eliseo; Blasco-Colmenares, Elena; Butcher, Barbara; Norgard, Sanaz; Nauffal, Victor; Marine, Joseph E.; Eldadah, Zayd; Dickfeld, Timm; Ellenbogen, Kenneth A.; Tomaselli, Gordon F.; Cheng, Alan

    2015-01-01

    BACKGROUND Heart failure patients with primary prevention implantable cardioverter-defibrillators (ICD) may experience an improvement in left ventricular ejection fraction (LVEF) over time. However, it is unclear how LVEF improvement affects subsequent risk for mortality and sudden cardiac death (SCD). OBJECTIVES We sought to assess changes in LVEF after ICD implantation and the implication of these changes on subsequent mortality and ICD shocks. METHODS We conducted a prospective cohort study of 538 patients with repeated LVEF assessments after ICD implantation for primary prevention of SCD. The primary endpoint was appropriate ICD shock, defined as a shock for ventricular tachyarrhythmias. The secondary endpoint was all-cause mortality. RESULTS Over a mean follow-up of 4.9 years, LVEF decreased in 13.0%, improved in 40.0%, and was unchanged in 47.0% of the patients. In the multivariate Cox models comparing patients with an improved LVEF to those with an unchanged LVEF, the hazard ratios were 0.33 (95% confidence interval [CI]: 0.18 to 0.59) for mortality and 0.29 (95% CI: 0.11 to 0.78) for appropriate shock, respectively. During follow-up, 25% of patients showed an improvement in LVEF to >35% and their risk of appropriate shock decreased but was not eliminated. CONCLUSION Among primary prevention ICD patients, 40.0% had an improved LVEF during follow-up and 25% had LVEF improved to >35%. Changes in LVEF were inversely associated with all-cause mortality and appropriate shock for ventricular tachyarrhythmia. In patients whose follow-up LVEF improved to >35%, the risk of an appropriate shock remained but was markedly decreased. PMID:26227190

  4. Relation of serum sodium level to long-term outcome after a first hospitalization for heart failure with preserved ejection fraction.

    PubMed

    Rusinaru, Dan; Buiciuc, Otilia; Leborgne, Laurent; Slama, Michel; Massy, Ziad; Tribouilloy, Christophe

    2009-02-01

    Hyponatremia is a predictor of adverse short-term outcomes in patients with acute heart failure (HF). The impact of hyponatremia on long-term survival in patients with HF with preserved ejection fraction (HFPEF) has not been evaluated. Our aim was to prospectively assess the impact of baseline natremia and changes in sodium level during hospitalization on 7-year outcome in 358 patients surviving a first hospitalization for HFPEF. On admission, hyponatremia (sodium <136 mEq/L) was diagnosed in 91 patients (25.4%). Baseline hyponatremia was associated with an increased risk of overall (hazard ratio [HR] 1.98, 95% confidence interval [CI] 1.50 to 2.61) and cardiovascular mortality (HR 1.92, 95% CI 1.36 to 2.73). After adjustment for covariates, the relations remained significant. Seven-year relative survival (observed/expected survival) of hyponatremic patients was lower than that of patients with normal baseline natremia (31% vs 63%). The association of sodium and risk of death appeared linear across quartiles of baseline natremia and slightly stronger at the lowest of sodium values. At discharge, 45 patients with low baseline sodium had normal natremia (49%) and 46 had persistent hyponatremia (51%). Patients with normalized natremia at discharge had excess 7-year overall mortality compared with the normonatremic group (HR 1.50, 95% CI 1.03 to 2.19). Patients with persistent hyponatremia had the lowest 7-year survival (HR 2.67, 95% CI 1.89 to 3.78). After adjustment for covariates, patients with persistent hyponatremia had an impressive increase in relative risk of overall mortality compared with patients with normal baseline natremia. In conclusion, hyponatremia is a powerful predictor of long-term mortality in patients with HFPEF. Patients with HFPEF and persistent hyponatremia are at high risk of adverse outcomes.

  5. Impact of Exhaled Breath Acetone in the Prognosis of Patients with Heart Failure with Reduced Ejection Fraction (HFrEF). One Year of Clinical Follow-up

    PubMed Central

    Saldiva, Paulo H. N.; Mangini, Sandrigo; Issa, Victor S.; Ayub-Ferreira, Silvia M.; Bocchi, Edimar A.

    2016-01-01

    Background The identification of new biomarkers of heart failure (HF) could help in its treatment. Previously, our group studied 89 patients with HF and showed that exhaled breath acetone (EBA) is a new noninvasive biomarker of HF diagnosis. However, there is no data about the relevance of EBA as a biomarker of prognosis. Objectives To evaluate whether EBA could give prognostic information in patients with heart failure with reduced ejection fraction (HFrEF). Methods After breath collection and analysis by gas chromatography-mass spectrometry and by spectrophotometry, the 89 patients referred before were followed by one year. Study physicians, blind to the results of cardiac biomarker testing, ascertained vital status of each study participant at 12 months. Results The composite endpoint death and heart transplantation (HT) were observed in 35 patients (39.3%): 29 patients (32.6%) died and 6 (6.7%) were submitted to HT within 12 months after study enrollment. High levels of EBA (≥3.7μg/L, 50th percentile) were associated with a progressively worse prognosis in 12-month follow-up (log-rank = 11.06, p = 0.001). Concentrations of EBA above 3.7μg/L increased the risk of death or HT in 3.26 times (HR = 3.26, 95%CI = 1.56–6.80, p = 0.002) within 12 months. In a multivariable cox regression model, the independent predictors of all-cause mortality were systolic blood pressure, respiratory rate and EBA levels. Conclusions High EBA levels could be associated to poor prognosis in HFrEF patients. PMID:28030609

  6. Usefulness of the QRS-T angle to improve long-term risk stratification of patients with acute myocardial infarction and depressed left ventricular ejection fraction.

    PubMed

    Raposeiras-Roubín, Sergio; Virgós-Lamela, Alejandro; Bouzas-Cruz, Noelia; López-López, Andrea; Castiñeira-Busto, María; Fernández-Garda, Rita; García-Castelo, Alberto; Rodríguez-Mañero, Moisés; García-Acuña, José María; Abu-Assi, Emad; González-Juanatey, José Ramón

    2014-04-15

    In light of the low cost, the widespread availability of the electrocardiogram, and the increasing economic burden of the health-related problems, we aimed to analyze the prognostic value of automatic frontal QRS-T angle to predict mortality in patients with left ventricular (LV) systolic dysfunction after acute myocardial infarction (AMI). About 467 consecutive patients discharged with diagnosis of AMI and with LV ejection fraction ≤40% were followed during 3.9 years (2.1 to 5.9). From them, 217 patients (47.5%) died. The frontal QRS-T angle was higher in patients who died (116.6±52.8 vs 77.9±55.1, respectively, p<0.001). The QRS-T angle value of 90° was the most accurate to predict all-cause cardiac death. After multivariate analysis, frontal QRS-T angle remained as an excellent predictor of all-cause and cardiac deaths, increasing the mortality 6% per each 10°. For the global mortality, the hazard ratio for a QRS-T angle>90° was 2.180 (1.558 to 3.050), and for the combined end point of cardiac death and appropriate implantable cardioverter defribrillator therapy, it was 2.385 (1.570 to 3.623). This independent predictive value was maintained even after adjusting by bundle brunch block, ST-elevation AMI, and its localization. In conclusion, a wide automatic frontal QRS-T angle (>90°) is a good discriminator of long-term mortality in patients with LV systolic dysfunction after an AMI. The ability to easily measure it from a standard 12-lead electrocardiogram together with its prognostic value makes the frontal QRS-T angle an attractive tool to help clinicians to improve risk stratification of those patients.

  7. Low-sodium dietary approaches to stop hypertension diet reduces blood pressure, arterial stiffness, and oxidative stress in hypertensive heart failure with preserved ejection fraction.

    PubMed

    Hummel, Scott L; Seymour, E Mitchell; Brook, Robert D; Kolias, Theodore J; Sheth, Samar S; Rosenblum, Hannah R; Wells, Joanna M; Weder, Alan B

    2012-11-01

    Recent studies suggest that oxidative stress and vascular dysfunction contribute to heart failure with preserved ejection fraction (HFPEF). In salt-sensitive HFPEF animal models, diets low in sodium and high in potassium, calcium, magnesium, and antioxidants attenuate oxidative stress and cardiovascular damage. We hypothesized that the sodium-restricted Dietary Approaches to Stop Hypertension diet (DASH/SRD) would have similar effects in human hypertensive HFPEF. Thirteen patients with treated hypertension and compensated HFPEF consumed the DASH/SRD for 21 days (all food/most beverages provided). The DASH/SRD reduced clinic systolic (155-138 mm Hg; P=0.02) and diastolic blood pressure (79-72 mm Hg; P=0.04), 24-hour ambulatory systolic (130-123 mm Hg; P=0.02) and diastolic blood pressure (67-62 mm Hg; P=0.02), and carotid-femoral pulse wave velocity (12.4-11.0 m/s; P=0.03). Urinary F2-isoprostanes decreased by 31% (209-144 pmol/mmol Cr; P=0.02) despite increased urinary aldosterone excretion. The reduction in urinary F2-isoprostanes closely correlated with the reduction in urinary sodium excretion on the DASH/SRD. In this cohort of HFPEF patients with treated hypertension, the DASH/SRD reduced systemic blood pressure, arterial stiffness, and oxidative stress. These findings are characteristic of salt-sensitive hypertension, a phenotype present in many HFPEF animal models and suggest shared pathophysiological mechanisms linking these 2 conditions. Further dietary modification studies could provide insights into the development and progression of hypertensive HFPEF.

  8. The relationship between mitral annular systolic velocity and ejection fraction in patients with preserved global systolic function of the left ventricle

    PubMed Central

    2013-01-01

    Background The aim of the study was to investigate the relationship between the ejection fraction (EF) and the mitral annular systolic velocity (Sm) in patients with preserved left ventricular systolic function (EF>55%). The study task was to evaluate whether the assessment of Sm(avg) can be used as an alternative to the Simpson’s method in assessment of the EF. The expected benefit was that Sm could be used to predict EF, when EF is difficult to assess due to poor image quality (IQ). Method Sm was obtained by spectral pulse wave Tissue Doppler Imaging (pwTDI) from the lateral and septal sites of the mitral annulus (MA) and an averaged value was calculated - Sm(avg). EF was assessed using Simpson’s rule. Participants were divided into controls (n=70), hypertensive (HTN, n=56), HTN with diastolic dysfunction (HTN/DD, n=65), HTN with diabetes mellitus (HTN/DM, n=52) and HTN with DD and DM (HTN/DD/DM, n=65). Results Sm(avg) showed strong correlation with EF (r=0.978; p<0.0001). There were no significant differences between the correlation coefficients between the subgroups and the controls. The mathematical model that the study recommended to assess the EF is: EF=45.0 + 2 × Sm(avg). Conclusion The assessment of Sm(avg) could be used as an alternative to EF. This approach may be useful especially when the IQ is poor. The method maintains high accuracy and reproducibility in prediction of the EF. PMID:24160570

  9. SIRT3-AMPK Activation by Nitrite and Metformin Improves Hyperglycemia and Normalizes Pulmonary Hypertension Associated with Heart Failure with Preserved Ejection Fraction (PH-HFpEF)

    PubMed Central

    Lai, Yen-Chun; Tabima, Diana M.; Dube, John J.; Hughan, Kara S.; Vanderpool, Rebecca R.; Goncharov, Dmitry A.; St Croix, Claudette M.; Garcia-Ocaña, Adolfo; Goncharova, Elena A.; Tofovic, Stevan P.; Mora, Ana L.; Gladwin, Mark T.

    2016-01-01

    Background Pulmonary hypertension associated with heart failure with preserved ejection fraction (PH-HFpEF) is an increasingly recognized clinical complication of metabolic syndrome. No adequate animal model of PH-HFpEF is available and no effective therapies have been identified to date. A recent study suggested that dietary nitrate improves insulin resistance in eNOS null mice, and multiple studies have reported that both nitrate and its active metabolite, nitrite, have therapeutic activity in pre-clinical models of PH. Methods and Results In order to evaluate the efficacy and mechanism of nitrite in metabolic syndrome associated with PH-HFpEF, we developed a “two-hit” PH-HFpEF model in rats with multiple features of metabolic syndrome due to double leptin receptor defect (obese ZSF1) with the combined treatment of VEGF receptor blocker SU5416. Chronic oral nitrite treatment improved hyperglycemia in obese ZSF1 rats by a process that requires skeletal muscle SIRT3-AMPK-GLUT4 signaling. The glucose lowering effect of nitrite was abolished in SIRT3 deficient human skeletal muscle cells, as well as in SIRT3 knockout mice fed a high-fat diet. Skeletal muscle biopsies from humans with metabolic syndrome after 12 weeks of oral sodium nitrite and nitrate treatment (IND#115926) displayed increased activation of SIRT3 and AMPK. Finally, early treatments with nitrite and metformin at the time of SU5416 injection reduced pulmonary pressures and vascular remodeling in the PH-HFpEF model with robust activation of skeletal muscle SIRT3 and AMPK. Conclusions These studies validate a rodent model of metabolic syndrome and PH-HFpEF, suggesting a potential role of nitrite and metformin as a preventative treatment for this disease. PMID:26813102

  10. Effect of Enhanced External Counter Pulsation Treatment on Aortic Blood Pressure, Arterial Stiffness and Ejection Fraction in Patients with Coronary Artery Disease

    PubMed Central

    Nayar, Sushma; Meyyappan, Chokkalingam; Ganesh, N; Chandrakasu, Arumugam; Nayar, Pradeep G

    2016-01-01

    Introduction Enhanced External Counter Pulsation (EECP) is a non-invasive treatment option for patients with Coronary Artery Disease (CAD). The treatment has shown to augment diastolic pressure and reduce Left Ventricular (LV) after-load by reducing systemic vascular resistance. The effect of EECP in standard brachial blood pressure and central haemodynamic parameters are not known. Aim We hypothesized that EECP may have differential effect in CAD patients with low systolic blood pressure when compared to normal systolic pressure and the mechanism underlying this differential effect may be due to improvement in LV function. Materials and Methods A total of 72 consecutive patients who underwent EECP treatment for symptomatic CAD with LV dysfunction were divided into two groups based on cut-off value of 100mmHg for systolic blood pressure. First group had patients with brachial systolic blood pressure of >100mmHg and second group had patients with brachial systolic blood pressure of ≤100mmHg. We measured central aortic systolic pressure, pulse pressure, augmentation index and augmentation pressure by SphygmoCor device and Ejection Fraction (EF) was measured by echo-cardiography. All these measurements were carried out prior to and after completion of 35 days of EECP sessions. Results Central systolic pressure, brachial systolic pressure, aortic pulse pressure, augmentation pressure and augmentation index significantly decreased in patients with normal brachial systolic pressure with baseline moderate LV dysfunction. Brachial systolic, aortic systolic and aortic pulse pressure significantly increased with no change in augmentation index and pressure is observed in patients with baseline severe LV dysfunction associated with low systolic pressure post EECP treatment. Conclusion EECP treatment has haemodynamically favourable differential effect in normal and low brachial systolic pressure and this is mainly driven by improvement in LV function in patients with

  11. A study of the dependence of protocol optimization on the left ventricular ejection fraction (LVEF) in coronary CT angiography (CCTA) examination

    NASA Astrophysics Data System (ADS)

    Yu, Dong-Su; Cho, Jae-Hwan; Park, Cheol-Soo; Yoo, Heung-Joon; Choi, Cheon-Woong; Kim, Dae-Hyun

    2013-10-01

    The purpose of this study is to obtain a good quality image and to minimize patient doses and re-examination rates through an optimization of the protocol for coronary computed tomography angiography (CCTA) examination based on a comparison and an analysis of the heart rates (HRs) of patients who had left ventricular ejection fraction (LVEF) values of less than 40% and the HRs of ordinary patients. This study targeted 16 patients who received thallium single-photon emission computed tomography (SPECT) or echocardiography simultaneously among the patients who took the CCTA examinations. Depending on the LVEF value (30 ˜ 39, 40 ˜ 49, 50 ˜ 59, and 60% or above), the patients were divided into groups of four based on HR (50 ˜ 59, 60 ˜ 69, 70 ˜ 79, and 80 or above). DynEva software was used to set the region of interest (ROI) on the ascending aorta and for a measurement of the threshold value. Comparisons and analyses were made based on the LVEF values and the HRs, after which the results were compared with the ones from the existing examination protocols and contrast medium protocols. According to the study results, the relation between the HR and the LVEF demonstrated that it took a long time to reach the true 100 hounsfield unit (HU) when the LVEF was 40% or below. Contrasting media showed significant differences, except in the case where the HR was 80 or above, and/or the LVEF was less than 40%. Moreover, for an LVEF of less than 40%, time differences were significant when contrasting media reached the true 100 HU to begin the scanning process. Therefore, it was possible to predict that the contrasting media were already being washed out from the left ventricle.

  12. Prevalence of heart failure with preserved ejection fraction in Latin American, Middle Eastern, and North African Regions in the I PREFER study (Identification of Patients With Heart Failure and PREserved Systolic Function: an epidemiological regional study).

    PubMed

    Magaña-Serrano, José A; Almahmeed, Wael; Gomez, Efrain; Al-Shamiri, Mostafa; Adgar, Djamila; Sosner, Philippe; Herpin, Daniel

    2011-11-01

    The aims of the present study were to estimate the prevalence of heart failure (HF) with preserved ejection fraction (HF-PEF) in patients with HF and to compare their clinical characteristics with those with reduced ejection fraction in non-Western countries. The left ventricular ejection fraction ≥ 45% if measured < 1 year before the visit was used to qualify the patients as having HF-PEF. Of the 2,536 consecutive outpatients with HF, 1990 (79%) had the EF values recorded. Of these patients, 1291 had HF-PEF, leading to an overall prevalence of 65% (95% confidence interval 63% to 67%). Compared to the patients with HF and a reduced ejection fraction, those with HF-PEF were more likely to be older (65 vs 62 years, p < 0.001), female (50% vs 28%, p < 0.001), and obese (39% vs 27%, p < 0.001). They more frequently had a history of hypertension (78% vs 53%, p < 0.001) and atrial fibrillation (29% vs 24%, p = 0.03) and less frequently had a history of myocardial infarction (21% vs 44%, p < 0.001). Only 29% of patients with HF-PEF and hypertension had optimal blood pressure control. Left ventricular hypertrophy was less frequent in those with HF-PEF (58% vs 69%, p < 0.001). The prevalence of HF-PEF was lower in the Middle East (41%), where coronary artery disease was more often found than in Latin America (69%) and North Africa (75%), where the rate of hypertension was greater. In conclusion, in the present diverse non-Western study, HF-PEF represented almost 2/3 of all HF cases in outpatients. HF-PEF mostly affects older patients, women, and the obese. Hypertension was the most frequently associated risk factor, highlighting the need for optimal blood pressure control.

  13. Material ejection

    NASA Technical Reports Server (NTRS)

    Webb, David F.; Forbes, Terry G.; Aurass, Henry; Chen, James; Martens, Piet; Rompolt, Bogdan; Rusin, Vojtech; Martin, Sara F.

    1994-01-01

    This paper reviews the major discussions and conclusions of the Flares 22 Workshop concerning the physical processes involved in mass ejecta events, with an emphasis on large-scale phenomena, especially Coronal Mass Ejections (CMEs). New insights have been gained from recent data obtained from the Solar Maximum Mission (SMM) and Yohkoh spacecraft and from several new ground-based radio and optical instruments, as well as from theoretical advances concerning the origins, driving mechanisms and long-term evolution of CMEs.

  14. Do Optimal Prognostic Thresholds in Continuous Physiological Variables Really Exist? Analysis of Origin of Apparent Thresholds, with Systematic Review for Peak Oxygen Consumption, Ejection Fraction and BNP

    PubMed Central

    Leong, Tora; Rehman, Michaela B.; Pastormerlo, Luigi Emilio; Harrell, Frank E.; Coats, Andrew J. S.; Francis, Darrel P.

    2014-01-01

    Background Clinicians are sometimes advised to make decisions using thresholds in measured variables, derived from prognostic studies. Objectives We studied why there are conflicting apparently-optimal prognostic thresholds, for example in exercise peak oxygen uptake (pVO2), ejection fraction (EF), and Brain Natriuretic Peptide (BNP) in heart failure (HF). Data Sources and Eligibility Criteria Studies testing pVO2, EF or BNP prognostic thresholds in heart failure, published between 1990 and 2010, listed on Pubmed. Methods First, we examined studies testing pVO2, EF or BNP prognostic thresholds. Second, we created repeated simulations of 1500 patients to identify whether an apparently-optimal prognostic threshold indicates step change in risk. Results 33 studies (8946 patients) tested a pVO2 threshold. 18 found it prognostically significant: the actual reported threshold ranged widely (10–18 ml/kg/min) but was overwhelmingly controlled by the individual study population's mean pVO2 (r = 0.86, p<0.00001). In contrast, the 15 negative publications were testing thresholds 199% further from their means (p = 0.0001). Likewise, of 35 EF studies (10220 patients), the thresholds in the 22 positive reports were strongly determined by study means (r = 0.90, p<0.0001). Similarly, in the 19 positives of 20 BNP studies (9725 patients): r = 0.86 (p<0.0001). Second, survival simulations always discovered a “most significant” threshold, even when there was definitely no step change in mortality. With linear increase in risk, the apparently-optimal threshold was always near the sample mean (r = 0.99, p<0.001). Limitations This study cannot report the best threshold for any of these variables; instead it explains how common clinical research procedures routinely produce false thresholds. Key Findings First, shifting (and/or disappearance) of an apparently-optimal prognostic threshold is strongly determined by studies' average pVO2, EF or BNP. Second

  15. Impact of epoetin alfa on left ventricular structure, function, and pressure volume relations as assessed by cardiac magnetic resonance: the heart failure preserved ejection fraction (HFPEF) anemia trial.

    PubMed

    Green, Philip; Babu, Benson A; Teruya, Sergio; Helmke, Stephen; Prince, Martin; Maurer, Mathew S

    2013-01-01

    Anemia, a common comorbidity in older adults with heart failure and a preserved ejection fraction (HFPEF), is associated with worse outcomes. The authors quantified the effect of anemia treatment on left ventricular (LV) structure and function as measured by cardiac magnetic resonance (CMR) imaging. A prospective, randomized single-blind clinical trial (NCT NCT00286182) comparing the safety and efficacy of epoetin alfa vs placebo for 24 weeks in which a subgroup (n=22) had cardiac magnetic resonance imaging (MRI) at baseline and after 3 and 6 months to evaluate changes in cardiac structure and function. Pressure volume (PV) indices were derived from MRI measures of ventricular volume coupled with sphygmomanometer-measured pressure and Doppler estimates of filling pressure. The end-systolic and end-diastolic PV relations and the area between them as a function of end-diastolic pressure, the isovolumic PV area (PVAiso), were calculated. Patients (75±10 years, 64% women) with HFPEF (EF=63%±15%) with an average hemoglobin of 10.3±1.1 gm/dL were treated with epoetin alfa using a dose-adjusted algorithm that increased hemoglobin compared with placebo (P<.0001). As compared with baseline, there were no significant changes in end-diastolic (-7±8 mL vs -3±8 mL, P=.81) or end-systolic (-0.4±2 mL vs -0.7±5 mL, P=.96) volumes at 6-month follow-up between epoetin alfa compared with placebo. LV function as measured based on EF (-1.5%±1.6% vs -2.6%±3.3%, P=.91) and pressure volume indices (PVAiso-EDP at 30 mm Hg, -5071±4308 vs -1662±4140, P=.58) did not differ between epoetin alfa and placebo. Administration of epoetin alfa to older adult patients with HFPEF resulted in a significant increase in hemoglobin, without evident change in LV structure, function, or pressure volume relationships as measured quantitatively using CMR imaging.

  16. Tocotrienol rich fraction reverses age-related deficits in spatial learning and memory in aged rats.

    PubMed

    Taridi, Nursiati Mohamad; Abd Rani, Nazirah; Abd Latiff, Azian; Ngah, Wan Zurinah Wan; Mazlan, Musalmah

    2014-09-01

    Little is known about the effect of vitamin E on brain function. Therefore, in this study we evaluated the effect of tocotrienol rich fraction (TRF) on behavioral impairment and oxidative stress in aged rats. Thirty-six male Wistar rats (young: 3-months-old; aged: 21-months-old) were treated with either the control (olive oil) or TRF (200 mg/kg) for 3 months. Behavioral studies were performed using the open field test and Morris water maze (MWM) task. Blood was taken for assessment of DNA damage, plasma malondialdehyde (MDA) and vitamin E, and erythrocyte antioxidant enzyme activity. Brains were also collected to measure vitamin E levels. Results showed that aged rats exhibited reduced exploratory activity, enhanced anxiety and decreased spatial learning and memory compared with young rats. DNA damage and plasma MDA were increased, and vitamin E levels in plasma and brain were reduced in aged rats. Aged rats supplemented with TRF showed a markedly reduced level of anxiety, improved spatial learning and memory, reduced amount and severity of DNA damage, a reduced level of MDA, and increased levels of antioxidant enzyme activity and plasma/brain vitamin E compared with age-matched controls. In conclusion, TRF supplementation reverses spatial learning and memory decline and decreases oxidative stress in aged rats.

  17. Impact of temperature on the aging mechanisms of arsenic in soils: fractionation and bioaccessibility.

    PubMed

    Huang, Guanxing; Chen, Zongyu; Wang, Jia; Hou, Qinxuan; Zhang, Ying

    2016-03-01

    The present study focused on the influence of temperature variation on the aging mechanisms of arsenic in soils. The results showed that higher temperature aggravated the decrease of more mobilizable fractions and the increase of less mobilizable or immobilizable fractions in soils over time. During the aging process, the redistribution of both carbonate-bound fraction and specifically sorbed and organic-bound fraction in soils occurred at various temperatures, and the higher temperature accelerated the redistribution of specifically sorbed and organic-bound fraction. The aging processes of arsenic in soils at different temperatures were characterized by several stages, and the aging processes were not complete within 180 days. Arsenic bioaccessibility in soils decreased significantly by the aging, and the decrease was intensified by the higher temperature. In terms of arsenic bioaccessibility, higher temperature accelerated the aging process of arsenic in soils remarkably.

  18. IMproved exercise tolerance in patients with PReserved Ejection fraction by Spironolactone on myocardial fibrosiS in Atrial Fibrillation rationale and design of the IMPRESS-AF randomised controlled trial

    PubMed Central

    Shantsila, Eduard; Haynes, Ronnie; Fisher, James; Kirchhof, Paulus; Gill, Paramjit S; Lip, Gregory Y H

    2016-01-01

    Introduction Patients with atrial fibrillation frequently suffer from heart failure with preserved ejection fraction. At present there is no proven therapy to improve physical capacity and quality of life in participants with permanent atrial fibrillation with preserved left ventricular contractility. Objective The single-centre IMproved exercise tolerance In heart failure With PReserved Ejection fraction by Spironolactone On myocardial fibrosiS In Atrial Fibrillation (IMPRESS-AF) trial aims to establish whether treatment with spironolactone as compared with placebo improves exercise tolerance (cardiopulmonary exercise testing), quality of life and diastolic function in patients with permanent atrial fibrillation. Methods and analysis A total of 250 patients have been randomised in this double-blinded trial for 2-year treatment with 25 mg daily dose of spironolactone or matched placebo. Included participants are 50 years old or older, have permanent atrial fibrillation and ejection fraction >55%. Exclusion criteria include contraindications to spironolactone, poorly controlled hypertension and presence of severe comorbidities with life expectancy <2 years. The primary outcome is improvement in exercise tolerance at 2 years and key secondary outcomes include quality of life (assessed using the EuroQol EQ-5D-5L (EQ-5D) and Minnesota Living with Heart Failure (MLWHF) questionnaires), diastolic function and all-cause hospitalisation. Ethics and dissemination The study has been approved by the National Research and Ethics Committee West Midlands—Coventry and Warwickshire (REC reference number 14/WM/1211). The results of the trial will be published in an international peer-reviewed journal. Trial registration numbers EudraCT2014-003702-33; NCT02673463; Pre-results. PMID:27707827

  19. Coronal Mass Ejections

    NASA Astrophysics Data System (ADS)

    Crooker, Nancy; Joselyn, Jo Ann; Feynman, Joan

    The early 1970's can be said to mark the beginning of The Enlightenment in the history of the Space Age, literally as well as by analogy to European history. Instruments blinded by Earth's atmosphere were lifted above and, for the first time, saw clearly and continuously the ethereal white light and sparkling x-rays from the solar corona. From these two bands of the light spectrum came images of coronal mass ejections and coronal holes, respectively. But whereas coronal holes were immediately identified as the source of high-speed solar wind streams, at first coronal mass ejections were greeted only by a sense of wonder. It took years of research to identify their signatures in the solar wind before the fastest ones could be identified with the well-known shock disturbances that cause the most violent space storms.

  20. Supercritical fractions as asphalt recycling agents and preliminary aging studies on recycled asphalts

    SciTech Connect

    Chaffin, J.M.; Liu, M.; Davison, R.R.; Glover, C.J.; Bullin, J.A.

    1997-03-01

    Several asphalts were fractionated using supercritical pentane. These fractions were analyzed by gel permeation chromatography and high-performance liquid chromatography, and their viscosities were measured. The properties of these fractions vary not only among the fractions of a given asphalt but also for the same fraction produced from different asphalts. These widely varied fractions previously have been shown to have potential for reblending to produce superior asphalts. This study investigates the potential for using some of the fractions as asphalt recycling agents. A modified strategic highway research program (SHRP) pressure aging vessel (PAV) test and kinetics studies were conducted on nine recycled asphalts and the original asphalt. The aging indexes of eight of the recycled asphalts are superior to the aging index of the original asphalt. Two of the blends using industrial supercritical fractions and the three blends using laboratory supercritical fractions have lower aging indexes than blends using commercial recycling agents. The kinetics investigation also indicates that at road conditions the recycled asphalts will harden more slowly than the original asphalt. The degree of hardening for a given amount of oxidation in the recycled binders was found to be a strong function of the total saturate content in the recycled binder.

  1. A tilting algorithm for the estimation of fractional age survival probabilities.

    PubMed

    Barz, Christiane; Müller, Alfred

    2012-04-01

    Life tables used in life insurance determine the age of death distribution only at integer ages. Therefore, actuaries make fractional age assumptions to interpolate between integer age values when they have to value payments that are not restricted to integer ages. Traditional fractional age assumptions as well as the fractional independence assumption are easy to apply but result in a non-intuitive overall shape of the force of mortality. Other approaches proposed either require expensive optimization procedures or produce many discontinuities. We suggest a new, computationally inexpensive algorithm to select the parameters within the LFM-family introduced by Jones and Mereu (Insur Math Econ 27:261-276, 2000). In contrast to previously suggested methods, our algorithm enforces a monotone force of mortality between integer ages if the mortality rates are monotone and keeps the number of discontinuities small.

  2. Validation of the FEW16 questionnaire for the assessment of physical well‐being in patients with heart failure with reduced ejection fraction: results from the CIBIS‐ELD study

    PubMed Central

    Lashki, D. J.; Trippel, T. D.; Tscholl, V.; Fritschka, M.; Musial‐Bright, L.; Busjahn, A.; Kolip, P.; Störk, S.; Rauchfuß, M.; Inkrot, S.; Lainscak, M.; Apostolović, S.; Vesković, J.; Lončar, G.; Doehner, W.; Zelenak, C.; Düngen, H. D.

    2015-01-01

    Abstract Aims Patients with heart failure (HF) commonly suffer from severe impairment of quality of life (QoL). One main goal of HF treatment is improvement of QoL. Physical well‐being is an essential component of QoL. To enable assessment of physical well‐being in HF patients, we validated the FEW16 questionnaire in a prospective study with patients from the Cardiac Insufficiency Bisoprolol Study in ELDerly. Methods and results In 127 HF patients (age 73 ± 5.5 years, 72% male, 60% New York Heart Association class II, left ventricular ejection fraction 37 ± 8.5%), we measured physical well‐being (FEW16), QoL [36‐Item Short‐Form Health Survey (SF36)], and depressive symptoms [PRIME MD Patient Health Questionnaire German short version for depression (PHQ‐D)] at baseline and two follow‐up visits, and correlated FEW16 scores with QoL data and clinical parameters. FEW16 mean scores are 3.04 ± 1.04 at baseline, 3.19 ± 0.94 after 3 months, and 2.77 ± 0.94 after 2–4 years. We assessed data quality, scale assumptions, and construct validity and reliability. Cronbach's alpha for subscales resilience: 0.84; ability to enjoy: 0.80; vitality: 0.88; inner peace: 0.87; total score: 0.95. Intraclass correlation coefficient (ICC) is 0.87 (95% CI 0.84–0.89, ICC (1.4). Pearson's correlations of FEW16 with SF36 and PHQ‐D were significant. Six minutes walking distance and heart rate correlated significantly with the FEW16 total score. Conclusions The FEW16 showed good reliability, internal consistency, and intraclass correlation. FEW16 scores correlated well with psychological and physical well‐being (SF36) and clinical markers of exercise tolerance (6 min walk test and heart rate). Our results indicate a strong correlation of self‐reported physical well‐being with psychological factors. FEW16 values at baseline predicted the development of several aspects of QoL during beta‐blocker up‐titration. PMID:27708856

  3. Growth response of weanling rats to heated, aged, fractionated, and chemically treated yogurts.

    PubMed

    Hargrove, R E; Alford, J A

    1980-07-01

    Significance of viable cultures in yogurt at time of ingestion on rate of growth of weaning rats was determined. Fresh yogurts were compared with those in which cultures were treated with heat, hydrogen peroxide, and ethylene oxide. They also were aged and freeze-dried. Fractions of yogurt prepared by ultrafiltration were recombined to determine which fraction gave the highest rate of gain in weight. Cultures were inactivated and growth in rats was depressed when yogurt was heated at 60 C and above for 2 min. Hydrogen peroxide reduced the viable yogurt count and rate of gain but not feed consumption. Yogurts treated with ethylene oxide were toxic. Aging did not effect culture viability or feed efficiency, but growth response was reduced. Fractionation of yogurt into components of high and low molecular weight and recombinations with control milk fractions indicated that the growth stimulant remained in the component of high molecular weight.

  4. Factors Affecting Ejection Risk in Rollover Crashes

    PubMed Central

    Funk, James R.; Cormier, Joseph M.; Bain, Charles E.; Wirth, Jeffrey L.; Bonugli, Enrique B.; Watson, Richard A.

    2012-01-01

    Ejection greatly increases the risk of injury and fatality in a rollover crash. The purpose of this study was to determine the crash, vehicle, and occupant characteristics that affect the risk of ejection in rollovers. Information from real world rollover crashes occurring from 2000 – 2010 was obtained from the National Automotive Sampling System (NASS) in order to analyze the effect of the following parameters on ejection risk: seatbelt use, rollover severity, vehicle type, seating position, roof crush, side curtain airbag deployment, glazing type, and occupant age, gender, and size. Seatbelt use was found to reduce the risk of partial ejection and virtually eliminate the risk of complete ejection. For belted occupants, the risk of partial ejection risk was significantly increased in rollover crashes involving more roof inversions, light trucks and vans (LTVs), and larger occupants. For unbelted occupants, the risk of complete ejection was significantly increased in rollover crashes involving more roof inversions, LTVs, far side occupants, and higher levels of roof crush. Roof crush was not a significant predictor of ejection after normalizing for rollover severity. Curtain airbag deployment was associated with reduced rates of partial and complete ejection, but the effect was not statistically significant, perhaps due to the small sample size (n = 89 raw cases with curtain deployments). A much greater proportion of occupants who were ejected in spite of curtain airbag deployment passed through the sunroof and other portals as opposed to the adjacent side window compared to occupants who were ejected in rollovers without a curtain airbag deployment. The primary factors that reduce ejection risk in rollover crashes are, in generally decreasing order of importance: seatbelt use, fewer roof inversions, passenger car body type, curtain airbag deployment, near side seating position, and small occupant size. PMID:23169130

  5. Increased Symmetric Dimethylarginine Level Is Associated with Worse Hospital Outcomes through Altered Left Ventricular Ejection Fraction in Patients with Acute Myocardial Infarction

    PubMed Central

    Lorin, Julie; Guilland, Jean-Claude; Stamboul, Karim; Guenancia, Charles; Cottin, Yves; Rochette, Luc; Vergely, Catherine; Zeller, Marianne

    2017-01-01

    Objectives We aimed to investigate whether SDMA- symmetric dimethylarginine -the symmetrical stereoisomer of ADMA- might be a marker of left ventricular function in AMI. Background Asymmetric dimethylarginine (ADMA) has been implicated in the prognosis after acute myocardial infarction (AMI) and heart failure (HF). Methods Cross sectional prospective study from 487 consecutive patients hospitalized <24 hours after AMI. Patients with HF on admission were excluded. Serum levels of ADMA, SDMA and L-arginine were determined using HPLC. Glomerular filtration rate (eGFR) was estimated based on creatinine levels. Outcomes were in-hospital severe HF, as defined by Killip class >2, and death. Results Patients were analysed based on SDMA tertiles. Sex, diabetes, dyslipidemia, and prior MI were similar for all tertiles. In contrast, age and hypertension increased across the tertiles (p<0.001). From the first to the last tertile, GRACE risk score was elevated while LVEF and eGFR was reduced. The rate of severe HF and death were gradually increased across the SDMA tertiles (from 0.6% to 7.4%, p = 0.006 and from 0.6% to 5.0%, p = 0.034, respectively). Backward logistic multivariate analysis showed that SDMA was an independent estimate of developing severe HF, even when adjusted for confounding (OR(95%CI): 8.2(3.0–22.5), p<0.001). Further, SDMA was associated with mortality, even after adjustment for GRACE risk score (OR(95%CI): 4.56(1.34–15.52), p = 0.015). Conclusions Our study showed for the first time that SDMA is associated with hospital outcomes, through altered LVEF and may have biological activity beyond renal function. PMID:28125604

  6. Ajmaline Challenge To Unmask Infrahisian Disease In Patients With Recurrent And Unexplained Syncope, Preserved Ejection Fraction, With Or Without Conduction Abnormalities On Surface ECG.

    PubMed

    Pentimalli, Francesco; Bacino, Luca; Ghione, Matteo; Giambattista, Siri; Gazzarata, Massimo; Bellotti, Paolo

    2016-01-01

    Background: Pharmacological challenge with class I antiarrhythmic drug is a recommended diagnostic test in patients with unexplained syncope only in the presence of bundle branch block, when non-invasive tests have failed to make the diagnosis. Its role in patients with minor or no conduction disturbances on 12-leads ECG has not been evaluated yet. It is also not clear which are the values of His-Ventricular interval to be considered diagnostic. We sought to evaluate the role of ajmaline challenge in unmasking the presence of an infrahisian disease in patients with recurrent and unexplained syncope, regardless of the existence of conduction disturbances on surface ECG. Materials And Methods: Patients with history of recurrent syncope, preserved EF and a negative first level workup were enrolled. Conduction disturbances on ECG were not considered as an exclusion criteria. During EPS, basal HV conduction was determined. In the presence of a HV >70 msec the study was interrupted and the patient was implanted with a pacemaker. If the HV was ≤ 70 msec, ajmaline was infused and HV was reassessed. The maximum value of HV was considered. A prolongation ≥ 100 msec was considered as diagnostic and indicative of conduction disease, and the patient underwent pacemaker implantation. Patients with an HV <100 msec were implanted with an ILR. Results: Sixteen consecutive patients were studied (age 76±5.2 years). Nine patients had conduction disturbances at baseline ECG (group ECG+). Among them, 5 had a basal diagnostic HV interval and 4 had a non-diagnostic HV interval. In the latter group, abnormal response to ajmaline was observed in 3 patients. In this group only one patient was implanted with an ILR, 8 patients were implanted with a pacemaker. Among the seven patients without conduction disturbances (group ECG-), no one had a diagnostic basal HV interval. After drug administration, 4 patients had a non-diagnostic response and were implanted with an ILR, while 3 patient

  7. Mammary cisternal size, cisternal milk and milk ejection in Murrah buffaloes.

    PubMed

    Thomas, Chirathalattu S; Svennersten-Sjaunja, Kerstin; Bhosrekar, Madhukar R; Bruckmaier, Rupert M

    2004-05-01

    The internal arrangement of the mammary gland cavity system, cisternal and alveolar milk fractions and the characteristics of milk ejection were investigated in buffaloes. Twenty-four Murrah buffaloes in three different stages of lactation and of two age groups were used. Continuous ultrasound cross-sections during milk ejection induced by exogenous oxytocin were performed to record the latency period of milk ejection. Buffaloes had small cisterns and the cavity area in the teat and gland regions were not significantly different (P > 0.05). The animals had long teat canals (3.1 +/- 0.1 cm), longer in the hind than fore quarters. Cisternal milk yield was low (0.17 +/- 0.01 kg) and cisternal fraction was only 4.9 +/- 0.1% of the total milk. The cisternal area (cm2) was 69.6 +/- 4.6, 51.61 +/- 4.8 and 26.01 +/- 4.8 while the cisternal yield (kg) was 0.32 +/- 0.05, 0.18 +/- 0.05 and 0.05 +/- 0.05 in early, mid and late lactation, respectively. A close correlation (r = 0.87, P < 0.05) existed between the ultrasound cisternal area and cisternal milk yield. The latency period of induced milk ejection was similar to that reported for cows (25 +/- 1 s) and was negatively correlated with milk yield (r = -0.75, P < 0.05). Milk ejection occurred shortly after elevated oxytocin concentrations were present. Delayed milk ejection reported earlier in this species must therefore be due to the absence of cisternal milk and delayed oxytocin release. An increase in teat length and circumference at milk ejection was also evident in the ultrasound cross sections.

  8. Effects of nonsaponin fraction of red ginseng on learning deficits in aged rats.

    PubMed

    Kurimoto, Hiroaki; Nishijo, Hisao; Uwano, Teruko; Yamaguchi, Hidetoshi; Zhong, Yong-Mei; Kawanishi, Kazuko; Ono, Taketoshi

    2004-09-15

    Previously we reported that oral application of red ginseng significantly ameliorated learning deficits in aged rats and young rats with hippocampal lesions. In the present study, we investigated the effects of the nonsaponin fraction of red ginseng on learning deficits in aged rats in behavioral studies and those on long-term potentiation (LTP) in the hippocampal CA3 subfield in young rats in electrophysiological studies. In the behavioral studies, three groups of rats [aged rats with and without oral administration of the nonsaponin fraction of red ginseng and young rats] were tested with the three types of spatial-learning task [distance movement task (DMT), random-reward place search task (RRPST), and place-learning task (PLT)] in a circular open field. The results in the DMT and RRPST indicated that motivational and motor activity was not significantly different among the three groups of rats. However, performance of the aged rats without nonsaponin was significantly impaired in the PLT when compared with the young rats. Treatment with nonsaponin significantly ameliorated deficits in place-navigation learning in the aged rats in the PLT. In the electrophysiological studies, effects of nonsaponin on the LTP in the CA3 subfield of the hippocampal slices were investigated in vitro. Pretreatment with nonsaponin significantly augmented the increase in population spike amplitudes in the CA3 subfield after LTP induction. These results suggest that the nonsaponin fraction of red ginseng contains important substances to improve learning and memory in aged rats and that this amelioration by nonsaponin might be attributed partly to augmentation of LTP in the CA3 subfield.

  9. A circulating myocardial depressant substance in humans with septic shock. Septic shock patients with a reduced ejection fraction have a circulating factor that depresses in vitro myocardial cell performance.

    PubMed Central

    Parrillo, J E; Burch, C; Shelhamer, J H; Parker, M M; Natanson, C; Schuette, W

    1985-01-01

    We have previously described a subpopulation of patients with septic shock who had a reversible depression of radionuclide-determined left ventricular ejection fraction (EF). To investigate the mechanism of this myocardial depression, an in vitro model of mammalian myocardial cell performance was established employing primary spontaneously beating rat myocardial cells. The contraction of a single cardiac cell was quantitated by recording the changes in area occupied by the cell during contraction and relaxation. In 20 septic shock patients during the acute phase, the mean left ventricular EF was decreased (mean = 0.33, normal mean = 0.50), and serum obtained during this acute phase induced a mean (+/- standard error of the mean) 33 +/- 4% decrease in extent and 25 +/- 4% decrease in velocity of myocardial cell shortening during contraction (P less than 0.001). In contrast, serum obtained from 11 of these same patients before shock (n = 2) or after recovery (n = 9) of the left ventricular EF (mean = 0.50) showed a return toward normal in extent and velocity of shortening (P less than 0.001). Sera from 17 critically ill nonseptic patients, from 10 patients with structural heart disease as a cause for a depressed EF, and from 12 healthy laboratory personnel, induced no significant changes in in vitro myocardial cell performance. In 20 patients during the acute phase of septic shock, the decreased EF in vivo demonstrated a significant correlation (r = +0.52, P less than 0.01) with a decrease in the extent of myocardial cell shortening in vitro. The quantitative and temporal correlation between the decreased left ventricular EF and this serum myocardial depressant substance argues for a pathophysiologic role for this depressant substance in producing the reversible cardiomyopathy seen during septic shock in humans. Images PMID:4056039

  10. Serum levels of NT- pro ANP, BNP, NT-pro BNP and function of the left atrium in patients with heart failure and preserved ejection fraction after myocardial infarction

    NASA Astrophysics Data System (ADS)

    Shurupov, V.; Suslova, T.; Ryabov, V.

    2015-11-01

    The objective of our study was to evaluate the levels of natriuretic peptides in patients (pts) with heart failure with preserved ejection fraction (HFpEF) in 12 month after ST elevation myocardial infarction (STEMI) with a focus on the function of left atrium (LA) and left ventricular (LV) filling pressure. 55 pts were included in the study. 6-minute walk test was performed. Echo exam was performed by the diagnostic system VIVID 7. BNP in whole blood was determined using the Triage ® Meter BNP test. The serum levels of NT-pro BNP, NT-pro ANP («Biomedica», Austria) were determined in blood samples by enzyme-linked immune-sorbent assay (ELISA). LA volume index were differences (16.03±3.39 ml/m2; 25.36±8.26 ml/m2; 29.41±9.46 ml/m2 accordingly I, II, III class) depending on severity of HF. Well as E/E' ratio were differences (7.5±1.4; 9.8±5.1; 13.5±7.6 accordingly I, II, III class) depending on severity of HF. The LA volume index correlated with levels of NT-pro ANP (R=0.29; p=0.04), levels of NT-pro BNP (R=0.37; p=0.01), levels of BNP (R=0.51; p=0.0001). The LV filling pressure correlated with levels of NT-pro ANP (R=0.45; p=0.002), levels of NT-pro BNP (R=0.49; p=0.001), levels of BNP (R=0.37; p=0.01).

  11. Hippocampal Neuron Number Is Unchanged 1 Year After Fractionated Whole-Brain Irradiation at Middle Age

    SciTech Connect

    Shi Lei Molina, Doris P.; Robbins, Michael E.; Wheeler, Kenneth T.; Brunso-Bechtold, Judy K.

    2008-06-01

    Purpose: To determine whether hippocampal neurons are lost 12 months after middle-aged rats received a fractionated course of whole-brain irradiation (WBI) that is expected to be biologically equivalent to the regimens used clinically in the treatment of brain tumors. Methods and Materials: Twelve-month-old Fischer 344 X Brown Norway male rats were divided into WBI and control (CON) groups (n = 6 per group). Anesthetized WBI rats received 45 Gy of {sup 137}Cs {gamma} rays delivered as 9 5-Gy fractions twice per week for 4.5 weeks. Control rats were anesthetized but not irradiated. Twelve months after WBI completion, all rats were anesthetized and perfused with paraformaldehyde, and hippocampal sections were immunostained with the neuron-specific antibody NeuN. Using unbiased stereology, total neuron number and the volume of the neuronal and neuropil layers were determined in the dentate gyrus, CA3, and CA1 subregions of hippocampus. Results: No differences in tissue integrity or neuron distribution were observed between the WBI and CON groups. Moreover, quantitative analysis demonstrated that neither total neuron number nor the volume of neuronal or neuropil layers differed between the two groups for any subregion. Conclusions: Impairment on a hippocampal-dependent learning and memory test occurs 1 year after fractionated WBI at middle age. The same WBI regimen, however, does not lead to a loss of neurons or a reduction in the volume of hippocampus.

  12. CFD Simulations of Vibration Induced Droplet Ejection.

    NASA Astrophysics Data System (ADS)

    James, Ashley; Smith, Marc K.; Glezer, Ari

    1998-11-01

    Vibration-induced droplet ejection is a process that occurs when a liquid droplet is placed on a vibrating membrane. Above a critical value of the excitation amplitude, Faraday waves form on the surface of the drop. As the amplitude is increased secondary drops are ejected from the wave crests. A Navier-Stokes solver designed to simulate the transient fluid mechanics of the process is presented. The solver is based on a MAC method on a staggered grid. A volume of fluid method is implemented to track the free surface. The volume fraction is advected via a second-order, unsplit method that minimizes numerical diffusion of the interface. Surface tension is incorporated as a continuum surface force. This work is intended to provide a comprehensive description of the fluid dynamics involved in vibration-induced droplet ejection, with the aim of understanding the mechanism behind the ejection process. The evolution of the interface through droplet ejection will be simulated. The dependence of the ejection process on the driving parameters will be evaluated and the resonance characteristics of the drop will be determined. The results of the computations will be compared with experimental results.

  13. Physical aging and structural recovery in a colloidal glass subjected to volume-fraction jump conditions

    NASA Astrophysics Data System (ADS)

    Peng, Xiaoguang; McKenna, Gregory B.

    2016-04-01

    Three important kinetic phenomena have been cataloged by Kovacs in the investigation of molecular glasses during structural recovery or physical aging. These are responses to temperature-jump histories referred to as intrinsic isotherms, asymmetry of approach, and memory effect. Here we use a thermosensitive polystyrene-poly (N -isopropylacrylamide)-poly (acrylic acid) core-shell particle-based dispersion as a colloidal model and by working at a constant number concentration of particles we use temperature changes to create volume-fraction changes. This imposes conditions similar to those defined by Kovacs on the colloidal system. We use creep experiments to probe the physical aging and structural recovery behavior of colloidal glasses in the Kovacs-type histories and compare the results with those seen in molecular glasses. We find that there are similarities in aging dynamics between molecular glasses and colloidal glasses, but differences also persist. For the intrinsic isotherms, the times teq needed for relaxing or evolving into the equilibrium (or stationary) state are relatively insensitive to the volume fraction and the values of teq are longer than the α -relaxation time τα at the same volume fraction. On the other hand, both of these times grow at least exponentially with decreasing temperature in molecular glasses. For the asymmetry of approach, similar nonlinear behavior is observed for both colloidal and molecular glasses. However, the equilibration time teq is the same for both volume-fraction up-jump and down-jump experiments, different from the finding in molecular glasses that it takes longer for the structure to evolve into equilibrium for the temperature up-jump condition than for the temperature down-jump condition. For the two-step volume-fraction jumps, a memory response is observed that is different from observations of structural recovery in two-step temperature histories in molecular glasses. The concentration dependence of the dynamics

  14. The clinical experience and efficacy of bipolar radiofrequency with fractional photothermolysis for aged Asian skin.

    PubMed

    Akita, Hirotaka; Sasaki, Ryosuke; Yokoyama, Yusuke; Negishi, Kei; Matsunaga, Kayoko

    2014-10-01

    Bipolar radiofrequency (RF) technology is developed based on fractional thermolysis, and the literature concerning the efficacy of the rejuvenation and treatment of acne scars has been reported in Europe and the United States of America. Therefore, we examined bipolar RF treatment using fractional thermolysis to evaluate the efficacy and safety of the treatment of Asian photo-aging skin, particularly 'wrinkles' and 'sagging.' Ten Japanese women (mean age: 58.6, skin type III-IV) received three fractional bipolar RF treatments every 4-6 weeks. For the objective evaluation, we evaluated the improvement of the wrinkles on the forehead, lateral canthus (crow's feet) and lower eyelid, and the sagging of the nasolabial fold using digital photographs captured using Visia(™) . For the subjective evaluation, the participants were asked to describe the improvements observed in the wrinkles on the forehead, lateral canthus (crow's feet) and lower eyelid, and sagging nasolabial fold and to evaluate the level pain experienced using a 10-point VAS score. The objective evaluation in each category showed significant improvements in the wrinkles on the lateral canthus (crow's feet) and lower eyelid. As for the nasolabial fold, 60% of the subjects showed improvements, scoring from good to excellent (51-100% improvement), although there was a little improvement of the wrinkle on the forehead. Similar improvements were observed in the subjective evaluation. During each treatment, oedema and erythema were observed in all participants, but the oedema disappeared the following day in all cases. However, mild erythema persisted for an average of 3.1 days. Micro debris disappeared after an average of 5.2 days. The participants were satisfied, as we allowed them to apply make-up the next day. There were no other severe adverse reactions observed during the treatment. The 10-point VAS score was 3.8, and no participants dropped out due to discomfort. Little improvement was observed in

  15. Association of N-terminal pro-brain natriuretic peptide with contrast-induced acute kidney injury and long-term mortality in patients with heart failure and mid-range ejection fraction: An observation study.

    PubMed

    Wang, Kun; Li, Hua-Long; Chen, Li-Ling; Bei, Wei-Jie; Lin, Kai-Yang; Smyth, Brendan; Chen, Shi-Qun; Guo, Xiao-Sheng; Guo, Wei; Liu, Yuan-Hui; Chen, Peng-Yuan; Chen, Ji-Yan; Chen, Kai-Hong; Liu, Yong; Tan, Ning

    2017-03-01

    The potential value of N-terminal pro-brain natriuretic peptide (NT-proBNP) for contrast-induced acute kidney injury (CI-AKI) in patients with heart failure and mid-range ejection fraction (HFmrEF) is unclear. We investigated whether NT-proBNP is associated with CI-AKI and long-term mortality following elective cardiac catheterization in patients with HFmrEF.A total of 174 consecutive patients with HFmrEF undergoing elective coronary angiography or intervention were enrolled. The primary endpoint was the development of CI-AKI, defined as an absolute increase of ≥0.3 mg/dL or ≥ 50% from baseline serum creatinine with 48 hours after contrast medium exposure. Receiver-operating characteristic curve analysis was conducted, and Youden index was used to determine the best cutoff NT-proBNP value. Multivariable logistic regression and Cox proportional hazards regression analyses were performed to identify the independent risk factors for CI-AKI and long-term mortality, respectively.The incidence of CI-AKI was 12.1%. Patients with CI-AKI had higher NT-proBNP values than those without (4373[1561.9-7470.5] vs 1303[625.2-2482.3], P = 0.003). Receiver-operating characteristic curve revealed that NT-proBNP was not significantly different from the Mehran risk score in predicting CI-AKI (area under the curve [AUC] = 0.723 vs 0.767, P = 0.516). The best cutoff NT-proBNP value for CI-AKI was 3299 pg/mL, with 70.6% sensitivity and 83.1% specificity. Multivariable analysis demonstrated that NT-proBNP ≥3299 pg/mL is significantly related to CI-AKI (odds ratio = 12.79; 95% confidence interval, 3.18-51.49; P < 0.001). Cox regression analysis showed that NT-proBNP ≥3299 pg/mL is associated with long-term mortality (adjusted hazard ratio = 11.91; 95%CI, 2.16-65.70; P = 0.004) during follow-up.In patients with HFmrEF, NT-proBNP ≥3299 pg/mL is associated with CI-AKI and long-term mortality following elective coronary angiography or

  16. Comparison of 5-Year Outcomes After Coronary Artery Bypass Grafting in Heart Failure Patients With Versus Without Preserved Left Ventricular Ejection Fraction (from the CREDO-Kyoto CABG Registry Cohort-2).

    PubMed

    Marui, Akira; Nishiwaki, Noboru; Komiya, Tatsuhiko; Hanyu, Michiya; Tanaka, Shiro; Kimura, Takeshi; Sakata, Ryuzo

    2015-08-15

    Heart failure (HF) with reduced left ventricular (LV) ejection fraction (HFrEF) is regarded as an independent risk factor for poor outcomes after coronary artery bypass grafting (CABG). However, the impact of HF with preserved EF (HFpEF) still has been unclear. We identified 1,877 patients who received isolated CABG of 15,939 patients who underwent first coronary revascularization enrolled in the CREDO-Kyoto (Coronary REvascularization Demonstrating Outcome Study in Kyoto) Registry Cohort-2. Of them, 1,489 patients had normal LV function (LVEF >50% without a history of HF; Normal group), 236 had HFrEF (LVEF ≤50% with HF), and 152 had HFpEF (LVEF >50% with HF). Preoperative LVEF was the lowest in the HFrEF group (62 ± 12%, 36 ± 9%, and 61 ± 7% for the Normal, HFrEF, and HFpEF groups, respectively; p <0.001). Unadjusted 30-day mortality rate was the highest in the HFrEF group (0.5%, 3.0%, and 0.7%; p = 0.003). However, cumulative incidences of all-cause death at 5-year was the highest in the HFpEF group (14%, 27%, and 32%, respectively; p <0.001). After adjusting confounders, the risk of all-cause death in the HFpEF group was greater than the Normal group (hazard ratio [HR] 1.42; 95% confidence interval [CI] 1.02 to 1.97; p = 0.04). The risk of all-cause death was not different between the HFpEF and the HFrEF groups (HR 0.88; 95% CI 0.61 to 1.29; p = 0.52). In addition, the risks of cardiac death and sudden death in the HFpEF group were greater than the Normal group (HR 2.14, 95% CI 1.32 to 3.49, p = 0.002; and HR 3.60, 95% CI 1.55 to 8.36, p = 0.003, respectively), and the risks of those end points were not different between the HFrEF and the HFpEF groups. Despite low 30-day mortality rate after CABG in patients with HFpEF, HFpEF was associated with high risks of long-term death and cardiovascular events. Patients with HFpEF, as well as HFrEF, should be carefully operated and followed up.

  17. Association of N-terminal pro-brain natriuretic peptide with contrast-induced acute kidney injury and long-term mortality in patients with heart failure and mid-range ejection fraction

    PubMed Central

    Wang, Kun; Li, Hua-long; Chen, Li-ling; Bei, Wei-jie; Lin, Kai-yang; Smyth, Brendan; Chen, Shi-qun; Guo, Xiao-sheng; Guo, Wei; Liu, Yuan-hui; Chen, Peng-yuan; Chen, Ji-yan; Chen, Kai-hong; Liu, Yong; Tan, Ning

    2017-01-01

    Abstract The potential value of N-terminal pro-brain natriuretic peptide (NT-proBNP) for contrast-induced acute kidney injury (CI-AKI) in patients with heart failure and mid-range ejection fraction (HFmrEF) is unclear. We investigated whether NT-proBNP is associated with CI-AKI and long-term mortality following elective cardiac catheterization in patients with HFmrEF. A total of 174 consecutive patients with HFmrEF undergoing elective coronary angiography or intervention were enrolled. The primary endpoint was the development of CI-AKI, defined as an absolute increase of ≥0.3 mg/dL or ≥ 50% from baseline serum creatinine with 48 hours after contrast medium exposure. Receiver-operating characteristic curve analysis was conducted, and Youden index was used to determine the best cutoff NT-proBNP value. Multivariable logistic regression and Cox proportional hazards regression analyses were performed to identify the independent risk factors for CI-AKI and long-term mortality, respectively. The incidence of CI-AKI was 12.1%. Patients with CI-AKI had higher NT-proBNP values than those without (4373[1561.9–7470.5] vs 1303[625.2–2482.3], P = 0.003). Receiver-operating characteristic curve revealed that NT-proBNP was not significantly different from the Mehran risk score in predicting CI-AKI (area under the curve [AUC] = 0.723 vs 0.767, P = 0.516). The best cutoff NT-proBNP value for CI-AKI was 3299 pg/mL, with 70.6% sensitivity and 83.1% specificity. Multivariable analysis demonstrated that NT-proBNP ≥3299 pg/mL is significantly related to CI-AKI (odds ratio = 12.79; 95% confidence interval, 3.18–51.49; P < 0.001). Cox regression analysis showed that NT-proBNP ≥3299 pg/mL is associated with long-term mortality (adjusted hazard ratio = 11.91; 95%CI, 2.16–65.70; P = 0.004) during follow-up. In patients with HFmrEF, NT-proBNP ≥3299 pg/mL is associated with CI-AKI and long-term mortality following elective coronary

  18. Estimating the age of healthy infants from quantitative myelin water fraction maps.

    PubMed

    Dean, Douglas C; O'Muircheartaigh, Jonathan; Dirks, Holly; Waskiewicz, Nicole; Lehman, Katie; Walker, Lindsay; Piryatinsky, Irene; Deoni, Sean C L

    2015-04-01

    The trajectory of the developing brain is characterized by a sequence of complex, nonlinear patterns that occur at systematic stages of maturation. Although significant prior neuroimaging research has shed light on these patterns, the challenge of accurately characterizing brain maturation, and identifying areas of accelerated or delayed development, remains. Altered brain development, particularly during the earliest stages of life, is believed to be associated with many neurological and neuropsychiatric disorders. In this work, we develop a framework to construct voxel-wise estimates of brain age based on magnetic resonance imaging measures sensitive to myelin content. 198 myelin water fraction (VF(M) ) maps were acquired from healthy male and female infants and toddlers, 3 to 48 months of age, and used to train a sigmoidal-based maturational model. The validity of the approach was then established by testing the model on 129 different VF(M) datasets. Results revealed the approach to have high accuracy, with a mean absolute percent error of 13% in males and 14% in females, and high predictive ability, with correlation coefficients between estimated and true ages of 0.945 in males and 0.94 in females. This work represents a new approach toward mapping brain maturity, and may provide a more faithful staging of brain maturation in infants beyond chronological or gestation-corrected age, allowing earlier identification of atypical regional brain development.

  19. A Flying Ejection Seat

    NASA Technical Reports Server (NTRS)

    Hollrock, R. H.; Barzda, J. J.

    1972-01-01

    To increase aircrewmen's chances for safe rescue in combat zones, the armed forces are investigating advanced escape and rescue concepts that will provide independent flight after ejection and thus reduce the risk of capture. One of the candidate concepts is discussed; namely, a stowable autogyro that serves as the crewman's seat during normal operations and automatically converts to a flight vehicle after ejection. Discussed are (1) the mechanism subsystems that the concept embodies to meet the weight and cockpit-packaging constraints and (2) tests that demonstrated the technical feasibility of the stowage, deployment, and flight operation of the rotor lift system.

  20. Chronic stroke and aging: the impact of acoustic stimulus intensity on fractionated reaction time.

    PubMed

    Coombes, Stephen A; Janelle, Christopher M; Cauraugh, James H

    2009-03-13

    In control samples, intense acoustic "go" stimuli accelerate the central and peripheral motor processes that compose simple reaction time movements. The goal of the current study was to determine whether movements that are initiated to intense acoustic cues facilitate simple reaction times in (1) adults with chronic stroke as compared to age matched controls and (2) in older as compared to younger adults. EMG and force data were collected from three groups (stroke, older adults, and younger adults) during a ballistic wrist and finger extension task. Movements were made to the onset of 80 dB and 107 dB acoustic cues and simple reaction times were fractionated into premotor and motor components. The present findings offer two important contributions to the literature. First, increases in stimulus intensity led to faster motor times in the impaired limb of stroke subjects. Second, increased stimulus intensity led to faster premotor reaction times across all groups, although an age rather than a stroke-specific motor deficit was evidenced, with the younger control group displaying significantly faster premotor times. Findings are integrated with previous evidence concerning post stroke corticospinal tract integrity and are interpreted via mechanisms which address stroke and age-related changes in motoneurons and activity in motor units.

  1. Early expectations of AMS: Greater ages and tiny fractions. One failure? — One success

    NASA Astrophysics Data System (ADS)

    Schmidt, Fred H.; Balsley, David R.; Leach, Donald D.

    1987-11-01

    Two of the early expectations of AMS were extension to greater 14C ages than possible with beta counting, and applications using tiny amounts of carbon. We examine each in the light of our experiences. The age limit depends on true or apparent ion counts, which may originate in sample preparation, in the accelerating system itself, or from ions other than 14C which are not adequately suppressed. 14N ions are generated spontaneously in our FN tandem, whether the ion source is open to the tandem or not, but are suppressed in the detector. There is no evidence of spontaneous 14C ion production. Thus the ion-source and tandem system alone is capable of age determinations ⩾ 90000 yr. For presumably "dead" geological graphite, we obtain a maximum of 70000 yr, and about 50000 yr for "dead" material which has undergone chemical and physical preparation. In this respect our full AMS system is at present a mixed success. However, our applications to small fractions have been quite successful. We have applied this advantage to the study of the organic carbon components present in the Amazon River and in deep sea cores.

  2. An improved snow hydrology for GCMS. Part 1: Snow cover fraction, albedo, grain size, and age

    SciTech Connect

    Marshall, S.; Oglesby, R.J.

    1994-07-01

    A new, physically-based snow hydrology has been implemented into the NCAR CCM1. The snow albedo is based on snow depth, solar zenith angle, snow cover pollutants, cloudiness, and a new parameter, the snow grain size. Snow grain size in turn depends on temperature and snow age. An improved expression is used for fractional snow cover which relates it to surface roughness and to snow depth. Each component of the new snow hydrology was implemented separately and then combined to make a new control run integrated for ten seasonal cycles. With the new snow hydrology, springtime snow melt occurs more rapidly, leading to a more reasonable late spring and summer distribution of snow cover. Little impact is seen on winter snow cover, since the new hydrology affects snow melt directly, but snowfall only indirectly, if at all. The influence of the variable grain size appears more important when snow packs are relatively deep while variable fractional snow cover becomes increasingly important as the snow pack thins. Variable surface roughness affects the snow cover fraction directly, but shows little effect on the seasonal cycle of the snow line. As an application of the new snow hydrology, we have rerun simulations involving Antarctic and Northern Hemisphere glaciation. Relatively little difference is seen for Antarctica, but a profound difference occurs for the Northern Hemisphere. In particular, ice sheets computed using new snow accumulations from the GCM are more numerous and larger in extent with the new snow hydrology. The new snow hydrology leads to a better simulation of the seasonal cycle of snow cover, however, our primary goal in implementing it into the GCM is to improve the predictive capabilities of the model. Since the snow hydrology is based on fundamental physical processes, and has well-defined parameters. it should enable model simulations of climatic change in which we have increased confidence. 37 refs., 15 figs., 2 tabs.

  3. Effect of temperature, ration, body size and age on sulphur isotope fractionation in fish.

    PubMed

    Barnes, Carolyn; Jennings, Simon

    2007-01-01

    Sulphur isotope analysis (delta(34)S) is increasingly identified as a valuable tool for source differentiation and the determination of trophic level in food webs, but there are still many uncertainties associated with the interpretation of delta(34)S data. To investigate the effects of temperature, ration, body size and age on sulphur trophic fractionation (Deltadelta(34)S) in fish, we reared European sea bass (Dicentrarchus labrax) on identical diets at 11 and 16 degrees C at three ration levels for over 600 days. Deltadelta(34)S was between 0 and -1 per thousand. The effect of temperature on Deltadelta(34)S was small and inconsistent, varying over the course of the experiment and depending on ration. This contrasts with temperature effects on bass Deltadelta(13)C and Deltadelta(15)N, where Deltadelta(13)C increases at warm temperatures while Deltadelta(15)N falls. Body size and age had a positive relationship with Deltadelta(34)S but the relationship with size was not significant for bass that weighed >20 g. As Deltadelta(34)S is small and the range in delta(34)S of potential diet items can be much greater than the range in delta(13)C or delta(15)N, our results show that sulphur stable isotopes are particularly useful for source differentiation in fish.

  4. Coronal mass ejections

    SciTech Connect

    Steinolfson, R.S.

    1990-01-01

    Coronal mass ejections (CMEs) are now recognized as an important component of the large-scale evolution of the solar corona. Some representative observations of CMEs are reviewed with emphasis on more recent results. Recent observations and theory are examined as they relate to the following aspects of CMEs: (1) the role of waves in determining the white-light signature; and (2) the mechanism by which the CME is driven (or launched) into the corona.

  5. Assessing changes in stratospheric mean age of air and fractional release using historical trace gas observations

    NASA Astrophysics Data System (ADS)

    Laube, Johannes; Bönisch, Harald; Engel, Andreas; Röckmann, Thomas; Sturges, William

    2014-05-01

    Large-scale stratospheric transport is pre-dominantly governed by the Brewer-Dobson circulation. Due to climatic change a long-term acceleration of this residual stratospheric circulation has been proposed (e.g. Austin et al.,2006). Observational evidence has revealed indications for temporary changes (e.g. Bönisch et al., 2011) but a confirmation of a significant long-term trend is missing so far (e.g. Engel et al., 2009). A different aspect is a possible long-term change in the break-down of chemically important species such as chlorofluorocarbons as proposed by Butchart et al. 2001. Recent studies show significant differences adding up to more than 20 % in the chlorine released from such compounds (Newman et al., 2007; Laube et al., 2013). We here use a data set of three long-lived trace gases, namely SF6, CF2Cl2, and N2O, as measured in whole-air samples collected during balloon and aircraft flights between 1975 and 2011, to assess changes in stratospheric transport and chemistry. For this purpose we utilise the mean stratospheric transit times (or mean ages of air) in combination with a measure of the chemical decomposition (i.e. fractional release factors). We also evaluate the influence of different trend correction methods on these quantities and explore their variability with latitude, altitude, and season. References Austin, J. & Li, F.: On the relationship between the strength of the Brewer-Dobson circulation and the age of stratospheric air, Geophys. Res. Lett., 33, L17807, 2006. Bönisch, H., Engel, A., Birner, Th., Hoor, P., Tarasick, D. W., and Ray, E. A.: On the structural changes in the Brewer-Dobson circulation after 2000, Atmos. Chem. Phys., 11, 3937-3948, 2011. Butchart, N. & Scaife, A. A. Removal of chlorofluorocarbons by increased mass exchange between the stratosphere and troposphere in a changing climate. Nature, 410, 799-802, 2001. Engel, A., Möbius, T., Bönisch, H., Schmidt, U., Heinz, R., Levin, I., Atlas, E., Aoki, S., Nakazawa, T

  6. Sedimentation field flow fractionation and flow field flow fractionation as tools for studying the aging effects of WO₃ colloids for photoelectrochemical uses.

    PubMed

    Contado, Catia; Argazzi, Roberto

    2011-07-08

    WO₃ colloidal suspensions obtained through a simple sol-gel procedure were subjected to a controlled temperature aging process whose time evolution in terms of particle mass and size distribution was followed by sedimentation field flow fractionation (SdFFF) and flow field flow fractionation (FlFFF). The experiments performed at a temperature of 60 °C showed that in a few hours the initially transparent sol of WO₃ particles, whose size was less than 25 nm, undergoes a progressive size increase allowing nanoparticles to reach a maximum equivalent spherical size of about 130 nm after 5 h. The observed shift in particle size distribution maxima (SdFFF), the broadening of the curves (FlFFF) and the SEM-TEM observations suggest a mixed mechanism of growth-aggregation of initial nanocrystals to form larger particles. The photoelectrochemical properties of thin WO₃ films obtained from the aged suspensions at regular intervals, were tested in a biased photoelectrocatalytic cell with 1M H₂SO₄ under solar simulated irradiation. The current-voltage polarization curves recorded in the potential range 0-1.8 V (vs. SCE) showed a diminution of the maximum photocurrent from 3.7 mA cm⁻² to 2.8 mA cm⁻² with aging times of 1h and 5h, respectively. This loss of performance was mainly attributed to the reduction of the electroactive surface area of the sintered particles as suggested by the satisfactory linear correlation between the integrated photocurrent and the cyclic voltammetry cathodic wave area of the W(VI)→W(V) process measured in the dark.

  7. Serum proteins and their fractions in the Timahdite sheep in Morocco: variations with age and with liver or lung diseases.

    PubMed

    Kessabi, M; Lamnaouer, D

    1981-01-01

    The serum proteins and their fractions were analyzed in the Moroccan "Timahdite" sheep. The values of those parameters in 20 two year-old adult animals were: total proteins 64.2 +/- 1.6 g/l; albumin 458 +/- 31 mumol/l; alpha-glob 11.9 +/- 1.0 g/l; beta-glob 6.2 +/- 1.6 g/l; gamma-glob 14.7 +/- 2.3 g/l. The total proteins increase with age is particularly due to an increase of the globulin fractions. In animals with liver or pulmonary affections the total proteins are increased. The amount of albumin is lower in liver diseases, whereas the globulin fractions are increased in both pathological processes.

  8. Improved Measurement of Ejection Velocities From Craters Formed in Sand

    NASA Technical Reports Server (NTRS)

    Cintala, Mark J.; Byers, Terry; Cardenas, Francisco; Montes, Roland; Potter, Elliot E.

    2014-01-01

    A typical impact crater is formed by two major processes: compression of the target (essentially equivalent to a footprint in soil) and ejection of material. The Ejection-Velocity Measurement System (EVMS) in the Experimental Impact Laboratory has been used to study ejection velocities from impact craters formed in sand since the late 1990s. The original system used an early-generation Charge-Coupled Device (CCD) camera; custom-written software; and a complex, multicomponent optical system to direct laser light for illumination. Unfortunately, the electronic equipment was overtaken by age, and the software became obsolete in light of improved computer hardware.

  9. Slingshot ejections from clusters of three and four black holes

    NASA Astrophysics Data System (ADS)

    Valtonen, M. J.; Mikkola, S.; Heinamaki, P.; Valtonen, H.

    1994-11-01

    This paper continues the investigation of the dynamical evolution of three- and four-black-hole clusters which arise in the centers of giant galaxies in successive galaxy mergers. About 100,000 three- and four-black-hole systems of varying initial compactness and drawn from different initial mass functions have been studied. Orbits have been calculated using a new method which allows the calculation of energy losses to gravitational radiation in four-body systems. We look for ejections of black holes from the galaxy and compare them with populations of extended radio sources. The main conclusions are the following: (1) In conditions prevailing after galaxy mergers, the chances that black holes are ejected out of the galaxy are improved if the initial number of black holes is at least four. (2) Ejections from four-black-hole systems happen easily. The common types of ejection are a one-sided ejection and a two-sided ejection with a 'remnant' central black hole. A two-sided ejection without a central black hole occurs in only a few percent of the cases. (3) The frequencies of different types of ejection agree with radio source populations only if many one-sided double sources have been misclassified as single-component sources. (4) In two-sided ejections the most common structure is the so-called dogleg structure of Stocke et al.; i.e., there is a major deviation from the opposite alignment of the ejected black holes as seen from the center of the galaxy. (5) The structures of the two-sided ejections agree with the double radio source populations only if many dogleg structures have been missed in the compilation of radio source samples. This could happen because of the overwhelming brightness of the central radio component. (6) If reasonable sample selection biases are introduced, the main properties of the ejection samples agree well with double radio source samples. The typical age of visibility of an ejected black hole is found to be about 108 years. We predict

  10. α-HCH enantiomer fraction (EF): A novel approach to calculate the ventilation age of water in the Arctic Ocean?

    NASA Astrophysics Data System (ADS)

    Pućko, Monika; Macdonald, Robie W.; Barber, David G.; Rosenberg, Bruno; Gratton, Yves; Stern, Gary A.

    2012-08-01

    α-HCH (hexachlorocyclohexane) and the enantiomeric fraction (EF) of its mirror-image isomers have been determined for water column profiles in the southern Beaufort Sea in 2004 and 2007. Using estimated rates of metabolic degradation, we have applied a simple kinetic model to convert the observed EFs to apparent ventilation ages of the water masses in the study region. We found an age of 1.7 ± 0.1 years for the Polar Mixed Layer (PML), 6.6 ± 0.6 for the core of the Pacific Layer centered at salinity 33.1, and 21.7 ± 0.5 years for the core of the Atlantic Layer identified by a Tmax of ˜0.5°C. These ages are in reasonable accord with other methods used to date water masses in the Arctic Ocean suggesting that α-HCH has an unexploited potential as a dating tool.

  11. Subproteomic analysis of basic proteins in aged skeletal muscle following offgel pre-fractionation.

    PubMed

    Gannon, Joan; Ohlendieck, Kay

    2012-04-01

    The progressive loss of skeletal muscle mass is a serious pathophysiological problem in the elderly, which warrants detailed biochemical studies into the underlying mechanism of age-related fiber degeneration. Over the last few years, mass spectrometry (MS)-based proteomics has identified a considerable number of new biomarkers of muscle aging in humans and animal models of sarcopenia. However, interpretation of the proteomic findings is often complicated by technical and biological limitations. Although gel electrophoresis-based approaches represent a highly sensitive analytical way for the large-scale and high-throughput survey of global changes in skeletal muscle proteins during aging, often the presence of components with an isoelectric point in the basic range is underestimated. We, therefore, carried out a comparative subproteomic study of young versus aged rat muscle focusing on potential changes in muscle proteins with an alkaline isoelectric point, using a combination of offgel electrophoresis and two-dimensional (2D) slab gel electrophoresis. Offgel electrophoresis was successfully applied as a prefractionation step to enrich basic protein species from crude tissue extracts representing young adult versus senescent muscle specimens. Proteomics has demonstrated alterations in a small cohort of basic proteins during muscle aging. The mass spectrometric identification of altered proteins and immunoblotting revealed a decrease in the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and a concomitant increase in mitochondrial creatine kinase (CK) and ubiquinol cytochrome‑c reductase. This agrees with the idea of a glycolytic-to-oxidative shift during muscle aging, which is indicative of an overall fast-to-slow transition process in senescent rat muscle. Thus, alterations in the abundance of metabolic enzymes appear to play a central role in the molecular pathogenesis of age‑dependent muscle wasting.

  12. Alterations in the sarcoplasmic protein fraction of beef muscle with postmortem aging and hydrodynamic pressure processing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Capillary electrophoresis (CE) and reversed-phase high performance liquid chromatography (RP-HPLC) analysis were utilized to detect differences in the sarcoplasmic protein profiles of beef strip loins subjected to aging and hydrodynamic pressure processing (HDP) treatments. At 48 h postmortem, stri...

  13. Fractionated Concurrent Exercise throughout the Day Does Not Promote Acute Blood Pressure Benefits in Hypertensive Middle-aged Women

    PubMed Central

    Azevêdo, Luan M.; de Souza, Alice C.; Santos, Laiza Ellen S.; Miguel dos Santos, Rodrigo; de Fernandes, Manuella O. M.; Almeida, Jeeser A.; Pardono, Emerson

    2017-01-01

    Hypertension is a chronic disease that affects about 30% of the world’s population, and the physical exercise plays an important role on its non-pharmacological treatment. Anywise, the dose–response of physical exercise fractionation throughout the day demands more investigation, allowing new exercise prescription possibilities. Therefore, this study aimed to analyze the acute blood pressure (BP) kinetics after 1 h of exercises and the BP reactivity after different concurrent exercise (CE) sessions and its fractioning of hypertensive middle-aged women. In this way, 11 hypertensive women voluntarily underwent three experimental sessions and one control day [control session (CS)]. In the morning session (MS) and night session (NS), the exercise was fully realized in the morning and evening, respectively. For the fractionized session (FS), 50% of the volume was applied in the morning and the remaining 50% during the evening. The MS provided the greatest moments (p ≤ 0.05) of post-exercise hypotension (PEH) for systolic BP (SBP) and highest reduction of BP reactivity for SBP (~44%) and diastolic BP (DBP) (~59%) compared to CS (p ≤ 0.05). The findings of the present study have shown that MS is effective for PEH to SBP, as well as it promotes high quality of attenuation for BP reactivity, greater than the other sessions. PMID:28261583

  14. Fractionated Concurrent Exercise throughout the Day Does Not Promote Acute Blood Pressure Benefits in Hypertensive Middle-aged Women.

    PubMed

    Azevêdo, Luan M; de Souza, Alice C; Santos, Laiza Ellen S; Miguel Dos Santos, Rodrigo; de Fernandes, Manuella O M; Almeida, Jeeser A; Pardono, Emerson

    2017-01-01

    Hypertension is a chronic disease that affects about 30% of the world's population, and the physical exercise plays an important role on its non-pharmacological treatment. Anywise, the dose-response of physical exercise fractionation throughout the day demands more investigation, allowing new exercise prescription possibilities. Therefore, this study aimed to analyze the acute blood pressure (BP) kinetics after 1 h of exercises and the BP reactivity after different concurrent exercise (CE) sessions and its fractioning of hypertensive middle-aged women. In this way, 11 hypertensive women voluntarily underwent three experimental sessions and one control day [control session (CS)]. In the morning session (MS) and night session (NS), the exercise was fully realized in the morning and evening, respectively. For the fractionized session (FS), 50% of the volume was applied in the morning and the remaining 50% during the evening. The MS provided the greatest moments (p ≤ 0.05) of post-exercise hypotension (PEH) for systolic BP (SBP) and highest reduction of BP reactivity for SBP (~44%) and diastolic BP (DBP) (~59%) compared to CS (p ≤ 0.05). The findings of the present study have shown that MS is effective for PEH to SBP, as well as it promotes high quality of attenuation for BP reactivity, greater than the other sessions.

  15. Climate Data Records (CDRs) for Ice Motion, Ice Age, and Melt Pond Fraction

    NASA Astrophysics Data System (ADS)

    Tschudi, M. A.; Maslanik, J. A.; Fowler, C.; Stroeve, J. C.; Rigor, I. G.

    2010-12-01

    Remotely-sensed Arctic sea ice motion, sea ice age, and melt pond coverage have been proposed for development into full CDRs. The first has a considerable history of use, while the latter two are relatively new products. Our technique to estimate sea ice motion utilizes images from SSM/I, as well as the Scanning Multichannel Microwave Radiometer (SMMR) and the series of Advanced Very High Resolution Radiometer (AVHRR) sensors to estimate the daily motion of ice parcels. This method is augmented by incorporating ice motion observations from the network of drifting buoys deployed as part of the International Arctic Buoy Program. Our technique to calculate ice age relies on following the actual age of the ice for each ice parcel, categorizing the parcel as first-year ice, second-year ice, etc. based on how many summer melt seasons the ice parcel survives. Our method to estimate melt pond coverage on sea ice involves solving a set of linear equations that relate each surface feature’s individual reflectance within the sensor’s (currently using the MODIS surface reflectance product, MOD09) pixel to the overall reflectance in that pixel. These three research-grade products have been interpolated onto 25x25 km grid points spanning the entire Arctic Ocean using the Equal-Area Scalable Earth (EASE) grid.

  16. Effect of age and eosinophil number on fractional exhaled nitric oxide level in non-asthmatic children in shanghai.

    PubMed

    Liu, Wei; Chu, Jizhi; Sun, Li; Shen, Zhiqin; Liu, Yan; Peng, Qing; Gao, Xiwen

    2014-10-01

    This study aimed to identify the relationship between fractional exhaled nitric oxide (FeNO) level and potential factors in non-asthmatic children from Shanghai, China. From March to April 2012, the school-aged children fulfilling the inclusion criteria were recruited. The FeNO levels of non-asthmatic children were detected by the Nano Coulomb nitric oxide analyzer. Questionnaires were recorded, including personal data, family illness history and daily habits. In addition, not only the number of leukocytes and eosinophils but also the level of hemoglobin in peripheral blood, were measured via the automated blood cell analyzer. All data were statistically analyzed with SPSS version 17.0 software and the correlation of these potential factors with FeNO level was calculated via Kendall's rank correlation. A total of 132 healthy children (aging 6-13 years) were enrolled in Minhang District, Shanghai, China. The mean value of FeNO level was 15.05 ppb. The correlation analyses revealed that age (R=0.190, p=0.029) and eosinophil number (R=0.575, p=0.000) were significantly and positively correlated with FeNO levels. The FeNO levels of individuals aged 10-13 years was significantly higher than those of the individuals aged 6-9 years (22.65 ± 18.82 ppb vs. 15.28 ± 9.78 ppb, p<0.05). However, other potential factors were not significantly correlated with FeNO level. The FeNO levels in healthy school-aged children may reflect airway eosinophilic inflammation levels, and was affected by eosinophil count and age significantly.

  17. Early life microbial exposure and fractional exhaled nitric oxide in school-age children: a prospective birth cohort study

    PubMed Central

    2013-01-01

    Background Inflammation is a key factor in the pathogenesis of respiratory diseases. Early life exposure to microbial agents may have an effect on the development of the immune system and on respiratory health later in life. In the present work we aimed to evaluate the associations between early life microbial exposures, and fractional exhaled nitric oxide (FeNO) at school age. Methods Endotoxin, extracellular polysaccharides (EPS) and β(1,3)-D-glucan were measured in living room dust collected at 2–3 months of age in homes of participants of three prospective European birth cohorts (LISA, n = 182; PIAMA, n = 244; and INMA, n = 355). Home dampness and pet ownership were periodically reported by the parents through questionnaires. FeNO was measured at age 8 for PIAMA and at age 10/11 for LISA and INMA. Cohort-specific associations between the indoor microbial exposures and FeNO were evaluated using multivariable regression analyses. Estimates were combined using random-effects meta-analyses. Results FeNO at school age was lower in children exposed to endotoxin at age 2–3 months (β -0.05, 95% confidence interval (CI) -0.10;-0.01) and in children with reported dog ownership during the first two years of life (GM ratio 0.82, CI 0.70-0.96). FeNO was not significantly associated with early life exposure to EPS, β(1,3)-D-glucan, indoor dampness and cat ownership. Conclusion Early life exposure to bacterial endotoxin and early life dog ownership are associated with lower FeNO at school age. Further studies are needed to confirm our results and to unravel the underlying mechanisms and possible clinical relevance of this finding. PMID:24295277

  18. Cortical Bone Water Concentration: Dependence of MR Imaging Measures on Age and Pore Volume Fraction

    PubMed Central

    Li, Cheng; Seifert, Alan C.; Rad, Hamidreza Saligheh; Bhagat, Yusuf A.; Rajapakse, Chamith S.; Sun, Wenli; Lam, Shing Chun Benny

    2014-01-01

    Purpose To quantify bulk bone water to test the hypothesis that bone water concentration (BWC) is negatively correlated with bone mineral density (BMD) and is positively correlated with age, and to propose the suppression ratio (SR) (the ratio of signal amplitude without to that with long-T2 suppression) as a potentially stronger surrogate measure of porosity, which is evaluated ex vivo and in vivo. Materials and Methods Human subject studies were conducted in compliance with institutional review board and HIPAA regulations. Healthy men and women (n = 72; age range, 20–80 years) were examined with a hybrid radial ultrashort echo time magnetic resonance (MR) imaging sequence at 3.0 T, and BWC was determined in the tibial midshaft. In a subset of 40 female subjects, the SR was measured with a similar sequence. Cortical volumetric BMD (vBMD) was measured by means of peripheral quantitative computed tomography (CT). The method was validated against micro-CT–derived porosity in 13 donor human cortical bone specimens. Associations among parameters were evaluated by using standard statistical tools. Results BWC was positively correlated with age (r = 0.52; 95% confidence interval [CI]: 0.22, 0.73; P = .002) and negatively correlated with vBMD at the same location (r = −0.57; 95% CI: −0.76, −0.29; P < .001). Data were suggestive of stronger associations with SR (r = 0.64, 95% CI: 0.39, 0.81, P < .001 for age; r = −0.67, 95% CI: −0.82, −0.43, P < .001 for vBMD; P < .001 for both), indicating that SR may be a more direct measure of porosity. This interpretation was supported by ex vivo measurements showing SR to be strongly positively correlated with micro-CT porosity (r = 0.88; 95% CI: 0.64, 0.96; P < .001) and with age (r = 0.87; 95% CI: 0.62, 0.96; P < .001). Conclusion The MR imaging–derived SR may serve as a biomarker for cortical bone porosity that is potentially superior to BWC, but corroboration in larger cohorts is indicated. © RSNA, 2014 PMID

  19. Specific absorbed fractions of energy at various ages from internal photon sources: 6, Newborn

    SciTech Connect

    Cristy, M.; Eckerman, K.F.

    1987-04-01

    Specific absorbed fraction (PHI's) in various organs of the body (target organs) from sources of monoenergetic photons in various other organs (source organs) are tabulated. In this volume PHI-values are tabulated for a newborn or 3.4-kg person. These PHI-values can be used in calculating the photon component of the dose-equivalent rate in a given target from a given radionuclide that is present in a given source organ. The International Commission on Radiological Protection recognizes that the endosteal, or bone surface, cells are the tissue at risk for bone cancer. We have applied the dosimetry methods that Spiers and co-workers developed for beta-emitting radionuclides deposited in bone to follow the transport of secondary electrons that were freed by photon interactions through the microscopic structure of the skeleton. With these methods we can estimate PHI in the endosteal cells and can better estimate PHI in the active marrow; the latter is overestimated with other methods at photon energies below 200 keV. 12 refs., 2 tabs.

  20. Mass ejections from the Sun

    NASA Astrophysics Data System (ADS)

    Green, Lucie M.

    Coronal mass ejections are the most spectacular form of solar activity and they play a key role in driving space weather at the Earth. These eruptions are associated with active regions and occur throughout an active region's entire lifetime. All coronal mass ejection models invoke the presence of a twisted magnetic field configuration known as a magnetic flux rope either before or after eruption onset. The observational identification of magnetic flux ropes in the solar atmosphere using remote sensing data represents a challenging task, but theoretical models have led to the understanding that there are signatures that reveal their presence. The range of coronal mass ejection models are helping build a more complete picture of both the trigger and drivers of these eruptions.

  1. The Solar Mass Ejection Imager

    NASA Technical Reports Server (NTRS)

    Jackson, B. V.; Buffington, A.; Hick, P. L.; Kahler, S. W.; Altrock, R. C.; Gold, R. E.; Webb, D. F.

    1995-01-01

    We are designing a Solar Mass Ejection Imager (SMEI) capable of observing the Thomson-scattered signal from transient density features in the heliosphere from a spacecraft situated near AU. The imager is designed to trace these features, which include coronal mass ejections. corotating structures and shock waves, to elongations greater than 90 deg from the Sun. The instrument may be regarded as a progeny of the heliospheric imaging capability shown possible by the zodiacal-light photometers of the HELIOS spacecraft. The instrument we are designing would make more effective use of in-situ solar wind data from spacecraft in the vicinity of the imager by extending these observations to the surrounding environment. The observations from the instrument should allow deconvolution of these structures from the perspective views obtained as they pass the spacecraft. An imager at Earth could allow up to three days warning of the arrival of a mass ejection from the Sun .

  2. The Relative Ages and Fractions of the Accreted and In Situ Populations in the Galactic Halo

    NASA Astrophysics Data System (ADS)

    Hawkins, K.; Jofré, P.; Masseron, T.

    2016-10-01

    The inner Galactic halo is thought to be formed by a combination of stars formed in situ and in dwarf galaxies that were accreted onto the Milky Way at later times. The two populations have been shown to be chemically distinct primarily in the α-elements such that the accreted population has lower [α/Fe] compared to the in situ stars at a constant metallicity. In this paper, we outline a powerful new spectral-indexing method to measure the [α/Fe] from low-resolution Sloan Digital Sky Survey spectra, and use the method in addition to turnoff temperature to study the relative age difference between, and age-metallicity relation of, the accreted and in situ populations. Our results indicate that at high metallicities the α-poor population is systematically younger than the α-rich population, but becomes coeval at low metallicities. Finally, we discuss the implication of this finding and potential applications for the new method.

  3. Age and thermal stability of particulate organic matter fractions indicate the presence of black carbon in soil

    NASA Astrophysics Data System (ADS)

    Leifeld, Jens; Heiling, Maria; Hajdas, Irka

    2014-05-01

    Black carbon (BC) from incomplete combustion is abundant in many soils. The age of black carbon is often higher than that of typical soil organic carbon (SOC) owing to its higher recalcitrance against microbial decomposition compared to plant residues. Also fossil BC may contribute to the high age of SOC. At the same time, the oxidative thermal stability of BC is known to be higher than that of SOC due to its chemical and physical structure. For a meaningful application of radiocarbon as an indicator for soil carbon age and turnover, the relative contribution of BC needs to be known but BC is difficult to separate physically from soil. Here we analyze particulate organic carbon (POC) fractions from four different field sites in Europe for their thermal stability using oxidative differential scanning calorimetry (DSC) and for their radiocarbon signature. POC may be particularly sensitive to BC 'contamination' because it was gained using a combination of size and density separation. One of these sites is essentially free of measurable amounts of BC. Each of the four sites comprised between five and eight individual POC samples taken from different spots. The radiocarbon signature and the calculated POC mean residence time of samples from three out of four sites indicated the presence of very old carbon, resulting in mean residence times (MRT) of several hundreds and up to 3700 years. In contrast, MRT's of POC from the virtually BC-free site were between 50 and 100 years. Two indicators for thermal stability of the POC fractions, i) the amount of heat released at temperatures > 450 °C and ii) the amount of heat released at 500 °C (where the latter represents the peak temperature of charcoal isolated from one of the samples) correlated both significantly and non-linearly with the samples MRT, indicating that samples with high BC content are older. Hence we can conclude that for an individual site with increasing abundance of BC both the age and the thermal stability

  4. Antioxidant enzyme activity and malondialdehyde levels can be modulated by Piper betle, tocotrienol rich fraction and Chlorella vulgaris in aging C57BL/6 mice

    PubMed Central

    Aliahmat, Nor Syahida; Noor, Mohd Razman Mohd; Yusof, Wan Junizam Wan; Makpol, Suzana; Ngah, Wan Zurinah Wan; Yusof, Yasmin Anum Mohd

    2012-01-01

    OBJECTIVE: The aim of this study was to determine the erythrocyte antioxidant enzyme activity and the superoxide dismutase, catalase, glutathione peroxidase, and plasma malondialdehyde levels in aging mice and to evaluate how these measures are modulated by potential antioxidants, including the tocotrienol-rich fraction, Piper betle, and Chlorella vulgaris. METHOD: One hundred and twenty male C57BL/6 inbred mice were divided into three age groups: young (6 months old), middle-aged (12 months old), and old (18 months old). Each age group consisted of two control groups (distilled water and olive oil) and three treatment groups: Piper betle (50 mg/kg body weight), tocotrienol-rich fraction (30 mg/kg), and Chlorella vulgaris (50 mg/kg). The duration of treatment for all three age groups was two months. Blood was withdrawn from the orbital sinus to determine the antioxidant enzyme activity and the malondialdehyde level. RESULTS: Piper betle increased the activities of catalase, glutathione peroxidase, and superoxide dismutase in the young, middle, and old age groups, respectively, when compared to control. The tocotrienol-rich fraction decreased the superoxide dismutase activity in the middle and the old age groups but had no effect on catalase or glutathione peroxidase activity for all age groups. Chlorella vulgaris had no effect on superoxide dismutase activity for all age groups but increased glutathione peroxidase and decreased catalase activity in the middle and the young age groups, respectively. Chlorella vulgaris reduced lipid peroxidation (malondialdehyde levels) in all age groups, but no significant changes were observed with the tocotrienol-rich fraction and the Piper betle treatments. CONCLUSION: We found equivocal age-related changes in erythrocyte antioxidant enzyme activity when mice were treated with Piper betle, the tocotrienol-rich fraction, and Chlorella vulgaris. However, Piper betle treatment showed increased antioxidant enzymes activity during

  5. Effect of aging on arsenic and lead fractionation and availability in soils: coupling sequential extractions with diffusive gradients in thin-films technique.

    PubMed

    Liang, Shuang; Guan, Dong-Xing; Ren, Jing-Hua; Zhang, Min; Luo, Jun; Ma, Lena Q

    2014-05-30

    We coupled the diffusive gradients in thin-films (DGT) technique with two sequential extraction methods to investigate the influence of aging on As and Pb fractionation and availability in three soils spiked with As (40 or 400mgkg(-1)), Pb (150 or 1500mgkg(-1)) or As+Pb (40mgkg(-1) As and 150mgkg(-1) Pb). During aging, As moved from the more available (non-specifically and specifically sorbed) to less available (amorphous and crystallized Fe/Al) fractions while Pb moved from the first three fractions (exchangeable, carbonate and Fe/Mn hydroxide) to organic fraction. However, even after 33-week aging, much more As and Pb were in the least available residual fraction in spiked soils than native soils (11-59% vs. 1.2-12%). Relatively, As in spiked soils was much more available than Pb with 11-14% As and 46-59% Pb in the residual fraction. Correlation analysis indicated that As in the non-specifically and specifically sorbed fractions and Pb in the exchangeable fraction were likely sources of DGT-measured labile As and Pb. The fact that As and Pb distribution and availability in spiked soils were significantly different from native soils suggests caution needs to be exercised when using spiked soils for research.

  6. Relationships between molecular weight and fluorescence properties for size-fractionated dissolved organic matter from fresh and aged sources.

    PubMed

    Cuss, C W; Guéguen, C

    2015-01-01

    Relationships between the molecular weight (MW) and fluorescence properties of dissolved organic matter (DOM) are important considerations for studies seeking to connect these properties to water treatment processes. Relationships between the size and fluorescence properties of nine allochthonous DOM sources (i.e. leaf leachates, grass, and headwaters) were measured using asymmetrical flow field-flow fractionation (AF4) with on-line absorbance and fluorescence detectors. Correlations between optical properties and MW were readily apparent using parallel factor analysis (PARAFAC) coupled to self-organizing maps (SOM): protein/polyphenol-like fluorescence (peaks B and T) was highest at lower molecular weights (<0.5 kDa), fulvic/humic-like fluorescence (peaks A, C, and M) was highest at mid-weights (0.5-1 kDa), and humic-like fluorescence (Peaks A + C) was highest at larger molecular weights (>1 kDa). Proportions of peaks B, T, and A + C were significantly correlated with MW (p < 0.001). The first principal component (PC1, 42% of variation in fluorescence properties) was a significant predictor of sample MW (R² = 0.63, p < 0.05), while scores on PC2 (27% of total variance) traced a source-based gradient from deciduous leachates/headwaters through to coniferous leachates/headwaters. PC3 (13% of var.) was also correlated with MW (p < 0.005). A secondary peak in peak T fluorescence was associated with larger size fractions in aged sources, and scores on PC1 also traced a path from the leachates of fresher leaves, through more humified leaves, to headwaters. Findings are consistent with the hypothesis that the structure of aged DOM arises through supramolecular assembly.

  7. Aerodynamic Forces Experienced during Ejection.

    DTIC Science & Technology

    1981-03-01

    BIOMECHANICAL DATA The blomechanical properties of long bones vary significantly with geometry, material properties , loading method, pathology, etc...side if neceseesary and Identify by block number) Ejection F -4 Aircraft Acceleration (abrupt Windblast Injury Biomechanical data Long bones 20...Ligaments-medial collateral tear-dislocation Menisci-medlal meniscus tear e Frequency: 44% e Mechanism: The function of the ligament Is to prevent abnormal

  8. Ventricular ejection force in growth-retarded fetuses.

    PubMed

    Rizzo, G; Capponi, A; Rinaldo, D; Arduini, D; Romanini, C

    1995-04-01

    The objective of this study was to determine whether in growth-retarded fetuses secondary to uteroplacental insufficiency the cardiac ventricles exert a force different from that of appropriately grown fetuses. Doppler echocardiographic studies were performed in 156 appropriately grown fetuses (gestational age 18-38 weeks) and in 72 growth-retarded fetuses (gestational age 24-36 weeks) free from structural and chromosomal abnormalities and characterized by Doppler changes in the umbilical artery and middle cerebral artery suggesting uteroplacental insufficiency as the most likely etiology of the growth defect. Right and left ventricular ejection force values were calculated from velocity waveforms recorded at the level of aortic and pulmonary valves, according to Newton's second law of motion. In appropriately grown fetuses, left and right ventricular ejection force values significantly increased with advancing gestation and the two ventricles exerted similar force. In growth-retarded fetuses, the ventricular ejection force was significantly and symmetrically decreased in both ventricles. Among growth-retarded fetuses, a poorer perinatal outcome was observed in those fetuses in which the ejection force of both ventricles was below the 5th centile of the normal limits for gestation. In 12 growth-retarded fetuses followed longitudinally during the last week preceding intrauterine death or Cesarean section due to antepartum heart-rate late decelerations, a significant decrease of ejection force was found in both ventricles. Finally, a significant relationship was found between the severity of acidosis and right and left ventricular ejection force values in 22 fetuses in which Doppler recordings were performed immediately before cordocentesis.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Experimentally induced, synergistic late effects of a single dose of radiation and aging: significance in LKS fraction as compared with mature blood cells.

    PubMed

    Hirabayashi, Yoko; Tsuboi, Isao; Nakachi, Kei; Kusunoki, Yoichiro; Inoue, Tohru

    2015-03-01

    The number of murine mature blood cells recovered within 6 weeks after 2-Gy whole-body irradiation at 6 weeks of age, whereas in the case of the undifferentiated hematopoietic stem/progenitor cell (HSC/HPC) compartment [cells in the lineage-negative, c-kit-positive and stem-cell-antigen-1-positive (LKS) fraction], the numerical differences between mice with and without irradiation remained more than a year, but conclusively the cells showed numerical recovery. When mice were exposed to radiation at 6 months of age, acute damages of mature blood cells were rather milder probably because of their maturation with age; but again, cells in the LKS fraction were specifically damaged, and their numerical recovery was significantly delayed probably as a result of LKS-specific cellular damages. Interestingly, in contrast to the recovery of the number of cells in the LKS fraction, their quality was not recovered, which was quantitatively assessed on the basis of oxidative-stress-related fluorescence intensity. To investigate why the recovery in the number of cells in the LKS fraction was delayed, expression levels of genes related to cellular proliferation and apoptosis of cells in the bone marrow and LKS fraction were analyzed by real-time polymerase chain reaction (RT-PCR). In the case of 21-month-old mice after radiation exposure, Ccnd1, PiK3r1 and Fyn were overexpressed solely in cells in the LKS fraction. Because Ccnd1and PiK3r1 upregulated by aging were further upregulated by radiation, single-dose radiation seemed to induce the acceleration of aging, which is related to the essential biological responses during aging based on a lifetime-dependent relationship between a living creature and xenobiotic materials.

  10. Two billion years of magmatism recorded from a single Mars meteorite ejection site.

    PubMed

    Lapen, Thomas J; Righter, Minako; Andreasen, Rasmus; Irving, Anthony J; Satkoski, Aaron M; Beard, Brian L; Nishiizumi, Kunihiko; Jull, A J Timothy; Caffee, Marc W

    2017-02-01

    The timing and nature of igneous activity recorded at a single Mars ejection site can be determined from the isotope analyses of Martian meteorites. Northwest Africa (NWA) 7635 has an Sm-Nd crystallization age of 2.403 ± 0.140 billion years, and isotope data indicate that it is derived from an incompatible trace element-depleted mantle source similar to that which produced a geochemically distinct group of 327- to 574-million-year-old "depleted" shergottites. Cosmogenic nuclide data demonstrate that NWA 7635 was ejected from Mars 1.1 million years ago (Ma), as were at least 10 other depleted shergottites. The shared ejection age is consistent with a common ejection site for these meteorites. The spatial association of 327- to 2403-Ma depleted shergottites indicates >2 billion years of magmatism from a long-lived and geochemically distinct volcanic center near the ejection site.

  11. Two billion years of magmatism recorded from a single Mars meteorite ejection site

    PubMed Central

    Lapen, Thomas J.; Righter, Minako; Andreasen, Rasmus; Irving, Anthony J.; Satkoski, Aaron M.; Beard, Brian L.; Nishiizumi, Kunihiko; Jull, A. J. Timothy; Caffee, Marc W.

    2017-01-01

    The timing and nature of igneous activity recorded at a single Mars ejection site can be determined from the isotope analyses of Martian meteorites. Northwest Africa (NWA) 7635 has an Sm-Nd crystallization age of 2.403 ± 0.140 billion years, and isotope data indicate that it is derived from an incompatible trace element–depleted mantle source similar to that which produced a geochemically distinct group of 327- to 574-million-year-old “depleted” shergottites. Cosmogenic nuclide data demonstrate that NWA 7635 was ejected from Mars 1.1 million years ago (Ma), as were at least 10 other depleted shergottites. The shared ejection age is consistent with a common ejection site for these meteorites. The spatial association of 327- to 2403-Ma depleted shergottites indicates >2 billion years of magmatism from a long-lived and geochemically distinct volcanic center near the ejection site. PMID:28164153

  12. Characterization of the evolution of the volume fraction of precipitates in aged AlMgSiCu alloys using DSC technique

    SciTech Connect

    Esmaeili, Shahrzad . E-mail: shahrzad@mecheng1.uwaterloo.ca; Lloyd, David J.

    2005-11-15

    Differential scanning calorimetry is used to quantify the evolution of the volume fraction of precipitates during age hardening in AlMgSiCu alloys. The calorimetry tests are run on alloy samples after aging for various times at 180 deg. C and the change in the collective heat effects from the major precipitation and dissolution processes in each run are used to determine the precipitation state of the samples. The method is implemented on alloys with various thermal histories prior to artificial aging, including commercial pre-aging histories. The estimated values for the relative volume fraction of precipitates are compared with the results from a newly developed analytical method using isothermal calorimetry and a related quantitative transmission electron microscopy work. Excellent agreement is obtained between the results from various methods.

  13. The role of continuous versus fractionated physical training on muscle oxidative stress parameters and calcium-handling proteins in aged rats.

    PubMed

    Tromm, Camila B; Pozzi, Bruna G; Paganini, Carla S; Marques, Scherolin O; Pedroso, Giulia S; Souza, Priscila S; Silveira, Paulo C L; Silva, Luciano A; De Souza, Claudio T; Pinho, Ricardo A

    2016-10-01

    Age-associated decline in skeletal muscle mass and strength is associated with oxidative stress and Ca(2+) homeostasis disturbance. Exercise should be considered a viable modality to combat aging of skeletal muscle. This study aimed to investigate whether continuous and fractionated training could be useful tools to attenuate oxidative damage and retain calcium-handling proteins. We conducted the study using 24-month-old male Wistar rats, divided into control, continuous, and fractionated groups. Animals ran at 13 m min(-1) for five consecutive days (except weekends) for 6 weeks, for a total period of 42 days. Each session comprised 45 min of exercise, either continuous or divided into three daily sessions of 15 min each. Metabolic and oxidative stress markers, protein levels of mitochondrial transcription factors, and calcium-handling proteins were analyzed. Continuous exercise resulted in reduced ROS production as well as showed a decrease in TBARS levels and carbonyl content. On the other hand, fractionated training increased the antioxidant enzyme activities. The ryanodine receptor and phospholamban protein were regulated by continuous training while sodium calcium exchange protein was increased by the fractionated training. These data suggest that intracellular Ca(2+) can be modulated by various training stimuli. In addition, the modulation of oxidative stress by continuous and fractionated training may play an important regulatory role in the muscular contraction mechanism of aged rats, due to changes in calcium metabolism.

  14. The need for T₂ correction on MRS-based vertebral bone marrow fat quantification: implications for bone marrow fat fraction age dependence.

    PubMed

    Dieckmeyer, Michael; Ruschke, Stefan; Cordes, Christian; Yap, Samuel P; Kooijman, Hendrik; Hauner, Hans; Rummeny, Ernst J; Bauer, Jan S; Baum, Thomas; Karampinos, Dimitrios C

    2015-04-01

    Vertebral bone marrow fat quantification using single-voxel MRS is confounded by overlapping water-fat peaks and the difference in T2 relaxation time between water and fat components. The purposes of the present study were: (i) to determine the proton density fat fraction (PDFF) of vertebral bone marrow using single-voxel multi-TE MRS, addressing these confounding effects; and (ii) to investigate the implications of these corrections with respect to the age dependence of the PDFF. Single-voxel MRS was performed in the L5 vertebral body of 86 subjects (54 women and 32 men). To reliably extract the water peak from the overlying fat peaks, the mean bone marrow fat spectrum was characterized based on the area of measurable fat peaks and an a priori knowledge of the chemical triglyceride structure. MRS measurements were performed at multiple TEs. The T2 -weighted fat fraction was calculated at each TE. In addition, a T2 correction was performed to obtain the PDFF and the T2 value of water (T2w ) was calculated. The implications of the T2 correction were investigated by studying the age dependence of the T2 -weighted fat fractions and the PDFF. Compared with the PDFF, all T2 -weighted fat fractions significantly overestimated the fat fraction. Compared with the age dependence of the PDFF, the age dependence of the T2 -weighted fat fraction showed an increased slope and intercept as TE increased for women and a strongly increased intercept as TE increased for men. For women, a negative association between the T2 value of bone marrow water and PDFF was found. Single-voxel MRS-based vertebral bone marrow fat quantification should be based on a multi-TE MRS measurement to minimize confounding effects on PDFF determination, and also to allow the simultaneous calculation of T2w , which might be considered as an additional parameter sensitive to the composition of the water compartment.

  15. Trends in 'cure' fraction from colorectal cancer by age and tumour stage between 1975 and 2000, using population-based data, Osaka, Japan.

    PubMed

    Ito, Yuri; Nakayama, Tomio; Miyashiro, Isao; Sugimoto, Tomoyuki; Ioka, Akiko; Tsukuma, Hideaki; Abdel-Rahman, Manar E; Rachet, Bernard

    2012-10-01

    Since the 1960s, Japan has experienced a striking increase in the incidence of colorectal cancer, now the second most common cancer in the country. Meanwhile, the management of colorectal cancer has changed dramatically with the implementation of, for example, screening, endoscopy and adjuvant chemotherapy. It is therefore of interest to monitor the long-term trends in population 'cure' in Japan. We analysed 33 885 colorectal cancer cases diagnosed between 1975 and 2000 in Osaka. We applied the multivariable mixture cure model to estimate cure fraction and median survival time (MST) for 'uncured' patients, by sex, age, stage, period at diagnosis and subsite. For colon cancer, the cure fraction increased by about 25%, while MST for the uncured was prolonged from 8 to 12 months. The cure fraction was 5% higher in men than in women, while MST was similar in both. The cure fraction also increased for localized and regional tumours. For rectal cancer, the cure fraction increased by about 25-30%, but remained lower than for colon cancer. From the late 1970s, the cure fraction for colorectal cancer increased dramatically due to better management of detection and care for colorectal cancer. This improvement was obtained at the cost of shorter MST for uncured patients.

  16. V are Interplanetary Coronal Mass Ejections Observed with the SOlar Mass Ejection Imager

    DTIC Science & Technology

    2007-01-01

    SUBTITLE V arc interplanetary coronal mass ejections observed with the Solar Mass Ejection Imager 5a. CONTRACT NUMBER 5b. GRANT NUMBER a. 5c...doi: 10.1029/2007JA012358 14. ABSTRACT Since February 2003, The Solar Mass Ejection Imager (SMEI) has been observing interplanetary- coronal mass...ejections (ICMEs) at solar elongation angles ^ > 20 degrees. The ICMEs generally appear as loops or arcs in the sky, but five show distinct outward

  17. Mass ejections. [during solar flares

    NASA Technical Reports Server (NTRS)

    Rust, D. M.; Hildner, E.; Hansen, R. T.; Dryer, M.; Mcclymont, A. N.; Mckenna-Lawlor, S. M. P.; Mclean, D. J.; Schmahl, E. J.; Steinolfson, R. S.; Tandberg-Hanssen, E.

    1980-01-01

    Observations and model simulations of solar mass ejection phenomena are examined in an investigation of flare processes. Consideration is given to Skylab and other observations of flare-associated sprays, eruptive prominences, surges and coronal transients, and to MHD, gas dynamic and magnetic loop models developed to account for them. Magnetic forces are found to confine spray material, which originates in preexisting active-region filaments, within steadily expanding loops, while surges follow unmoving, preexisting magnetic field lines. Simulations of effects of a sudden pressure pulse at the bottom of the corona are found to exhibit many characteristics of coronal transients associated with flares, and impulsive heating low in the chromosphere is found to be able to account for surges. The importance of the magnetic field as the ultimate source of energy which drives eruptive phenomena as well as flares is pointed out.

  18. Modeling Interplanetary Coronal Mass Ejections

    NASA Technical Reports Server (NTRS)

    Riley, Pete

    2004-01-01

    Heliospheric models of Coronal Mass Ejection (CME) propagation and evolution provide an important insight into the dynamics of CMEa and are a valuable tool for interpreting interplanetary in situ observations. Moreover, they represent a virtual laboratory for exploring conditions and regions of space that are not conveniently or currently accessible by spacecraft. In this review I summarize recent advances in modeling the properties and evolution of CMEs in the solar wind. In particular, I will focus on: (1) the types of ICME models; (2) the boundary conditions that are imposed, (3) the role of the ambient solar wind; (4) predicting new phenomena; and (5) distinguishing between competing CME initiation mechanisms. I will conclude by discussing what topics will likely be important for models to address in the future.

  19. Rehabilitation Enablement in Chronic Heart Failure—a facilitated self-care rehabilitation intervention in patients with heart failure with preserved ejection fraction (REACH-HFpEF) and their caregivers: rationale and protocol for a single-centre pilot randomised controlled trial

    PubMed Central

    Lang, C C; Smith, K; Jolly, K; Davis, R; Hayward, C; Wingham, J; Abraham, C; Green, C; Warren, F C; Britten, N; Greaves, C J; Doherty, P; Austin, J; Van Lingen, R; Singh, S; Buckingham, S; Paul, K; Taylor, R S; Dalal, H M

    2016-01-01

    Introduction The Rehabilitation EnAblement in CHronic Heart Failure in patients with Heart Failure (HF) with preserved ejection fraction (REACH-HFpEF) pilot trial is part of a research programme designed to develop and evaluate a facilitated, home-based, self-help rehabilitation intervention to improve self-care and quality of life (QoL) in heart failure patients and their caregivers. We will assess the feasibility of a definitive trial of the REACH-HF intervention in patients with HFpEF and their caregivers. The impact of the REACH-HF intervention on echocardiographic outcomes and bloodborne biomarkers will also be assessed. Methods and analysis A single-centre parallel two-group randomised controlled trial (RCT) with 1:1 individual allocation to the REACH-HF intervention plus usual care (intervention) or usual care alone (control) in 50 HFpEF patients and their caregivers. The REACH-HF intervention comprises a REACH-HF manual with supplementary tools, delivered by trained facilitators over 12 weeks. A mixed methods approach will be used to assess estimation of recruitment and retention rates; fidelity of REACH-HF manual delivery; identification of barriers to participation and adherence to the intervention and study protocol; feasibility of data collection and outcome burden. We will assess the variance in study outcomes to inform a definitive study sample size and assess methods for the collection of resource use and intervention delivery cost data to develop the cost-effectiveness analyses framework for any future trial. Patient outcomes collected at baseline, 4 and 6 months include QoL, psychological well-being, exercise capacity, physical activity and HF-related hospitalisation. Caregiver outcomes will also be assessed, and a substudy will evaluate impact of the REACH-HF manual on resting global cardiovascular function and bloodborne biomarkers in HFpEF patients. Ethics and dissemination The study is approved by the East of Scotland Research Ethics

  20. Initiation of Coronal Mass Ejections

    NASA Technical Reports Server (NTRS)

    Moore, Ronald L.; Sterling, Alphonse C.

    2005-01-01

    This paper is a synopsis of the initiation of the strong-field magnetic explosions that produce large, fast coronal mass ejections. Cartoons based on observations are used to describe the inferred basic physical processes and sequences that trigger and drive the explosion. The magnetic field that explodes is a sheared-core bipole that may or may not be embedded in surrounding strong magnetic field, and may or may not contain a flux rope before it starts to explode. We describe three different mechanisms that singly or in combination trigger the explosion: (1) runaway internal tether-cutting reconnection, (2) runaway external tether-cutting reconnection, and (3) ideal MHD instability or loss or equilibrium. For most eruptions, high-resolution, high-cadence magnetograms and chromospheric and coronal movies (such as from TRACE and/or Solar-B) of the pre-eruption region and of the onset of the eruption and flare are needed to tell which one or which combination of these mechanisms is the trigger. Whatever the trigger, it leads to the production of an erupting flux rope. Using a simple model flux rope, we demonstrate that the explosion can be driven by the magnetic pressure of the expanding flux rope, provided the shape of the expansion is "fat" enough.

  1. Dynamics of polymer ejection from capsid

    NASA Astrophysics Data System (ADS)

    Linna, R. P.; Moisio, J. E.; Suhonen, P. M.; Kaski, K.

    2014-05-01

    Polymer ejection from a capsid through a nanoscale pore is an important biological process with relevance to modern biotechnology. Here, we study generic capsid ejection using Langevin dynamics. We show that even when the ejection takes place within the drift-dominated region there is a very high probability for the ejection process not to be completed. Introducing a small aligning force at the pore entrance enhances ejection dramatically. Such a pore asymmetry is a candidate for a mechanism by which viral ejection is completed. By detailed high-resolution simulations we show that such capsid ejection is an out-of-equilibrium process that shares many common features with the much studied driven polymer translocation through a pore in a wall or a membrane. We find that the ejection times scale with polymer length, τ ˜Nα. We show that for the pore without the asymmetry the previous predictions corroborated by Monte Carlo simulations do not hold. For the pore with the asymmetry the scaling exponent varies with the initial monomer density (monomers per capsid volume) ρ inside the capsid. For very low densities ρ ≤0.002 the polymer is only weakly confined by the capsid, and we measure α =1.33, which is close to α =1.4 obtained for polymer translocation. At intermediate densities the scaling exponents α =1.25 and 1.21 for ρ =0.01 and 0.02, respectively. These scalings are in accord with a crude derivation for the lower limit α =1.2. For the asymmetrical pore precise scaling breaks down, when the density exceeds the value for complete confinement by the capsid, ρ ⪆0.25. The high-resolution data show that the capsid ejection for both pores, analogously to polymer translocation, can be characterized as a multiplicative stochastic process that is dominated by small-scale transitions.

  2. Pathfinder landing sites at candidate SNC impact ejection sites

    NASA Technical Reports Server (NTRS)

    Golombek, Matthew P.

    1994-01-01

    If Mars Pathfinder were able to land at a site on Mars from which the SNC meteorites were ejected by impact, the Pathfinder mission would essentially represent a very inexpensive sample return mission. Geologic units that contain four potential impact craters from which SNC meteorites could have been ejected from Mars are accessible to the Mars Pathfinder lander. Determining that SNC meteorites came from a particular spot on Mars raises the intriguing possibility of using Pathfinder as a sample return mission and providing a radiometric age for the considerably uncertain martian crater-age timescale. Pathfinder instruments are capable of determining if the rock type at the landing site is similar to that of one or more of the SNC meteorites, which would strengthen the hypothesis that the SNC meteorites did, in fact, come from Mars. Unfortunately, instrument observations from Pathfinder are probably not capable of determining if the geologic unit sampled by the lander is definitively the unit from which a SNC meteorite came from as opposed to Mars in general or perhaps a particular region on Mars. This abstract evaluates the possibility of landing at potential SNC ejection sites and the ability of Pathfinder to identify the landing site as the place from which an SNC meteorite came.

  3. SM-ND Age and REE Systematics of Larkman Nunatek 06319: Closed System Fractional Crystallization of a Shergottite Magma

    NASA Technical Reports Server (NTRS)

    Shafer, J. T.; Brandon, A. D.; Lapen T. J.; Righter, M.; Peslier, A. H.

    2010-01-01

    Sm-Nd isotopic data were collected on mineral separates and bulk rock powders of LAR 06319, yielding an age of 180+/-13 Ma (2(sigma)). This age is concordant with the Lu-Hf age (197+/-29 Ma, [1]) determined in conjunction with these data and the Sm-Nd age (190+/-26 Ma) of Shih et al., 2009 [2]. The Sm-Nd data form at statistically significant isochron (Fig. 1) that is controlled largely by leachate-residue pairs (samples with the R suffix are residues after leaching in cold 2N HCl for 10 minutes).

  4. Cheese peptidomics: a detailed study on the evolution of the oligopeptide fraction in Parmigiano-Reggiano cheese from curd to 24 months of aging.

    PubMed

    Sforza, S; Cavatorta, V; Lambertini, F; Galaverna, G; Dossena, A; Marchelli, R

    2012-07-01

    In this work, we performed a detailed evaluation of the evolution of the oligopeptide fractions in samples of Parmigiano-Reggiano cheese from the curd up to 24 mo of aging. The samples were taken from wheels produced the same day, in the same factory, from the same milk, during the same caseification process, thus simplifying the natural variability of a whey-based starter fermentation. This unique and homogeneous sampling plan, never reported before in the literature, provided a detailed study of the peptides produced by enzymatic events during Parmigiano-Reggiano aging. Given the large dimensions of the 35-kg wheels of Parmigiano-Reggiano, samples were taken from both the internal and external parts of the cheese, to evidence eventual differences in the oligopeptide composition of the different parts. Fifty-seven peptides were considered, being among the most abundant during at least one of the periods of ripening considered, and their semiquantification indicated that the peptide fraction of Parmigiano-Reggiano cheese constantly evolves during the aging period. Five trends in its evolution were outlined, which could be clearly correlated to the enzymatic activities present in the cheese, making it possible to discriminate cheeses according to their aging time. Several known bioactive peptides were also found to be present in Parmigiano-Reggiano cheese samples, and for the first time, the age at which they are most abundant has been identified. Aged cheeses have been shown to be dominated by nonproteolytic aminoacyl derivatives, a new class of peptide-like molecules recently reported. Finally, the changing peptide pattern may be related to the changing enzymatic activities occurring inside the cheeses during the aging period, which, in turn, are also related to the microbiological composition.

  5. Aug. 31, 2012 Coronal Mass Ejection

    NASA Video Gallery

    This two part movie shows an Aug. 31 coronal mass ejection (CME) from the sun , the same event that caused depletion and refilling of the radiation belts just after the Relativistic Electron-Proton...

  6. Sept. 28, 2012 Coronal Mass Ejection

    NASA Video Gallery

    This Sept. 28 coronal mass ejection (CME) from the sun, captured by NASA’s Solar Dynamics Observatory (SDO), is the event which caused the near total annihilation of the new radiation belt and sl...

  7. Omnidirectional and Controllable Wing Using Fluid Ejection

    DTIC Science & Technology

    1996-10-22

    8217 Q edge along a continuous perimeter from which fluid outflow tangential to the Coanda edge is -1 o selectively effected by omnidirectional...the air flow over the wing ’ ^ surfaces is directed internally within the fuselage. The tangential ejection of fluid outflow over Coanda edge...tangential ejection 2 outflow from a Coanda edge of a lift wing independently of its translation direction through an d ambient fluid so as

  8. Age and sex differences in the incorporation of EPA and DHA into plasma fractions, cells and adipose tissue in humans

    PubMed Central

    Walker, Celia G.; Browning, Lucy M.; Mander, Adrian P.; Madden, Jackie; West, Annette L.; Calder, Philip C.; Jebb, Susan A.

    2015-01-01

    The aims of this study were to determine whether age and sex influence both the status and the incorporation of EPA and DHA into blood plasma, cells and tissues. The study was a double-blind, randomised, controlled intervention, providing EPA+DHA equivalent to 0, 1, 2 or 4 portions of oily fish per week, for 12 months. Participants were stratified by age and sex. A linear regression model was used to analyse baseline outcomes, with covariates for age or sex groups, and adjusting for BMI. The change from baseline to 12 months in outcome was analysed with additional adjusting of treatment and average compliance. Fatty acid profiles were determined in plasma phosphatidylcholine (PC), cholesteryl esters (CE), NEFA and TAG, mononuclear cells (MNC), erythrocyte membranes (RBC), platelets (PLAT), buccal cells (BU) and adipose tissue (AT). At baseline, EPA concentration in plasma NEFA and DHA concentration in MNC, BU and AT was higher in females than males (all P<0.05). EPA in AT (P=0.003) and DHA in plasma TAG (P<0.01) and AT (P<0.001) were higher with increasing age. Following 12 months supplementation with EPA+DHA, adjusted mean difference for change in EPA in plasma TAG was significantly higher in females than males (P<0.05) and was greater with increasing age (P=0.02). Adjusted mean difference for change in DHA in AT was significantly smaller with increasing age (P=0.02). Although small differences in incorporation with age and sex were identified, these were not of sufficient magnitude to warrant a move away from population-level diet recommendations for n-3 PUFA. PMID:24063767

  9. Age and sex differences in the incorporation of EPA and DHA into plasma fractions, cells and adipose tissue in humans.

    PubMed

    Walker, Celia G; Browning, Lucy M; Mander, Adrian P; Madden, Jackie; West, Annette L; Calder, Philip C; Jebb, Susan A

    2014-02-01

    The aim of the present study was to determine whether age and sex influence both the status and incorporation of EPA and DHA into blood plasma, cells and tissues. The study was a double-blind, randomised, controlled intervention trial, providing EPA plus DHA equivalent to 0, 1, 2 or 4 portions of oily fish per week for 12 months. The participants were stratified by age and sex. A linear regression model was used to analyse baseline outcomes, with covariates for age or sex groups and by adjusting for BMI. The change in outcomes from baseline to 12 months was analysed with additional adjustment for treatment and average compliance. Fatty acid profiles in plasma phosphatidylcholine, cholesteryl esters, NEFA and TAG, mononuclear cells (MNC), erythrocyte membranes, platelets, buccal cells (BU) and adipose tissue (AT) were determined. At baseline, EPA concentrations in plasma NEFA and DHA concentrations in MNC, BU and AT were higher in females than in males (all P< 0·05). The concentrations of EPA in AT (P= 0·003) and those of DHA in plasma TAG (P< 0·01) and AT (P< 0·001) were higher with increasing age. Following 12-month supplementation with EPA plus DHA, adjusted mean difference for change in EPA concentrations in plasma TAG was significantly higher in females than in males (P< 0·05) and was greater with increasing age (P= 0·02). Adjusted mean difference for change in DHA concentrations in AT was significantly smaller with increasing age (P= 0·02). Although small differences in incorporation with age and sex were identified, these were not of sufficient magnitude to warrant a move away from population-level diet recommendations for n-3 PUFA.

  10. Influence of secondary preparative parameters and aging effects on PLGA particle size distribution: a sedimentation field flow fractionation investigation.

    PubMed

    Contado, Catia; Vighi, Eleonora; Dalpiaz, Alessandro; Leo, Eliana

    2013-01-01

    Poly(lactic-co-glycolic acid) particles in the 200-400-nm size range were formulated through nanoprecipitation and solvent evaporation methods. Different concentrations of the polymer and stabilizer (Pluronic® F 68) were tested in order to identify the best conditions for making poly(lactic-co-glycolic acid) particles of suitable size, stable in time, and to be used as carriers for brain-targeting drugs. The particles with the best characteristics for delivery system design were those formulated by nanoprecipitation with an organic/water phase ratio of 2:30, a polymer concentration of 25 mg/mL, and a surfactant concentration of 0.83 mg/mL; their surface charge was reasonably negative (approximately -27 mV) and the average size of the almost monodisperse population was roughly 250 nm. Particle characterization was obtained through ζ-potential measurements, scanning electron microscope observations, and particle size distribution determinations; the latter achieved by both photon-correlation spectroscopy and sedimentation field flow fractionation. Sedimentation field flow fractionation, which is considered more reliable than photon-correlation spectroscopy in describing the possible particle size distribution modifications, was used to investigate the effects of 3 months of storage at 4 °C had on the lyophilized particles. Figure Particle size ditribution from the SdFFF and the PCS techniques.

  11. Influence of alternating soil drying and wetting on the desorption and distribution of aged 14C-labeled pesticide residues in soil organic fractions

    NASA Astrophysics Data System (ADS)

    Jablonowski, N. D.; Mucha, M.; Thiele, B.; Hofmann, D.; Burauel, P.

    2012-04-01

    A laboratory experiment was conducted to evaluate the effect of alternating soil drying and wetting on the release of aged 14C-labeled pesticide residues and their distribution in soil organic fractions (humic acids, fulvic acids, and humin substances). The used soils (gleyic cambisol; Corg 1.2%, pH 7.2) were obtained from the upper soil layer of two individual outdoor lysimeter studies containing either environmentally long-term aged 14C residues of the herbicide ethidimuron (ETD; 0-10 cm depth; time of aging: 9 years) or methabenzthiazuron (MBT; 0-30 cm depth; time of aging: 17 years). Triplicate soil samples (10 g dry soil equivalents) were (A=dry/wet) previously dried (45° C) or (B=wet/wet) directly mixed with pure water (1+2, w:w), shaken (150 rpm, 1 h), and centrifuged (~2000 g). The resulting supernatant was removed, filtered (0.45 μm) and subjected to 14C activity analysis via liquid scintillation counter (LSC), dissolved organic carbon (DOC) analysis, and LC-MS-MS analysis. This extraction procedure was repeated 15 individual times, for both setups (A) and (B). To determine the distribution of the aged 14C labelled pesticide residues in the soil organic matter fractions, the soil samples were subject to humic and fulvic acids fractionations at cycles 0, 4, 10, and 15. The residual pesticide 14C activity associated with the humic, fulvic, and humin substances (organic fraction remaining in the soil) fractions was determined via LSC. The water-extracted residual 14C activity was significantly higher in the extracts of the dry/wet, compared to the wet/wet soil samples for both pesticides. The total extracted 14C activity in the dry/wet soil extracts accounted for 51.0% (ETD) and 15.4% (MBT) in contrast to 19.0% (ETD) and 4.7% (MBT) in the wet/wet extracts after 15 water extractions. LC-MS-MS analysis revealed the parent compound ETD 27.9 μg kg-1 soil (dry/wet) and 10.7 μg kg-1 soil (wet/wet), accounting for 3.45 and 1.35% of total parent compound

  12. Fractional anisotropy shows differential reduction in frontal-subcortical fiber bundles—A longitudinal MRI study of 76 middle-aged and older adults

    PubMed Central

    Vik, Alexandra; Hodneland, Erlend; Haász, Judit; Ystad, Martin; Lundervold, Astri J.; Lundervold, Arvid

    2015-01-01

    Motivated by the frontal- and white matter (WM) retrogenesis hypotheses and the assumptions that fronto-striatal circuits are especially vulnerable in normal aging, the goal of the present study was to identify fiber bundles connecting subcortical nuclei and frontal areas and obtain site-specific information about age related fractional anisotropy (FA) changes. Multimodal magnetic resonance image acquisitions [3D T1-weighted and diffusion weighted imaging (DWI)] were obtained from healthy older adults (N = 76, range 49–80 years at inclusion) at two time points, 3 years apart. A subset of the participants (N = 24) was included at a third time-point. In addition to the frontal-subcortical fibers, the anterior callosal fiber (ACF) and the corticospinal tract (CST) was investigated by its mean FA together with tract parameterization analysis. Our results demonstrated fronto-striatal structural connectivity decline (reduced FA) in normal aging with substantial inter-individual differences. The tract parameterization analysis showed that the along tract FA profiles were characterized by piece-wise differential changes along their extension rather than being uniformly affected. To the best of our knowledge, this is the first longitudinal study detecting age-related changes in frontal-subcortical WM connections in normal aging. PMID:26029102

  13. Effect of aging on the bioavailability and fractionation of arsenic in soils derived from five parent materials in a red soil region of Southern China.

    PubMed

    Wang, Yanan; Zeng, Xibai; Lu, Yahai; Su, Shiming; Bai, Lingyu; Li, Lianfang; Wu, Cuixia

    2015-12-01

    The effects of aging time and soil parent materials on the bioavailability and fractionations of arsenic (As) in five red soils were studied. The results indicated that As bioavailability in all soils decreased during aging, especially with a sharp decline occurring in the first 30 days. After aging for 360 days, the highest available As concentration, which accounted for 12.3% of the total, was observed in soils derived from purple sandy shale. While 2.67% was the lowest proportion of the available As in soils derived from quaternary red clay. Furthermore, the best fit of the available As changing with aging time was obtained using the pseudo-second-order model (R(2) = 0.939-0.998, P < 0.05). Notably, Al oxides played a more crucial role (R(2) = 0.89, P<0.05) than did Fe oxides in controlling the rate of As aging. The non-specially and specially absorbed As constituted the primary forms of available As.

  14. The Cardiac Cycle and the Physiological Basis of Left Ventricular Contraction, Ejection, Relaxation, and Filling

    PubMed Central

    Fukuta, Hidekatsu; Little, William C.

    2008-01-01

    Synopsis Heart failure is defined as the pathological state in which the heart is unable to pump blood at a rate required by the metabolizing tissues or can do so only with an elevated filling pressure. Heart failure in adults most frequently results from the inability of the left ventricle to fill (diastolic performance) and/or eject (systolic performance) blood. The severity of heart failure and its prognosis are more closely related to the degree of diastolic filling abnormalities than the ejection fraction. This underscores the importance of understanding the mechanisms of diastolic abnormalities in heart failure. PMID:18313620

  15. Can Kindergartners Do Fractions?

    ERIC Educational Resources Information Center

    Cwikla, Julie

    2014-01-01

    Mathematics professor Julie Cwikla decided that she needed to investigate young children's understandings and see what precurricular partitioning notions young minds bring to the fraction table. Cwikla realized that only a handful of studies have examined how preschool-age and early elementary school-age students solve fraction problems (Empson…

  16. Numerical Simulations of a Flux Rope Ejection

    NASA Astrophysics Data System (ADS)

    Pagano, P.; Mackay, D. H.; Poedts, S.

    2015-03-01

    Coronal mass ejections (CMEs) are the most violent phenomena observed on the Sun. One of the most successful models to explain CMEs is the flux rope ejection model, where a magnetic flux rope is expelled from the solar corona after a long phase along which the flux rope stays in equilibrium while magnetic energy is being accumulated. However, still many questions are outstanding on the detailed mechanism of the ejection and observations continuously provide new data to interpret and put in the context. Currently, extreme ultraviolet (EUV) images from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO) are providing new insights into the early phase of CME evolution. In particular, observations show the ejection of magnetic flux ropes from the solar corona and how they evolve into CMEs. However, these observations are difficult to interpret in terms of basic physical mechanisms and quantities, thus, we need to compare equivalent quantities to test and improve our models. In our work, we intend to bridge the gap between models and observations with our model of flux rope ejection where we consistently describe the full life span of a flux rope from its formation to ejection. This is done by coupling the global non-linear force-free model (GNLFFF) built to describe the slow low- β formation phase, with a full MHD simulation run with the software MPI-AMRVAC, suitable to describe the fast MHD evolution of the flux rope ejection that happens in a heterogeneous β regime. We also explore the parameter space to identify the conditions upon which the ejection is favoured (gravity stratification and magnetic field intensity) and we produce synthesised AIA observations (171 Å and 211 Å). To carry this out, we run 3D MHD simulation in spherical coordinates where we include the role of thermal conduction and radiative losses, both of which are important for determining the temperature distribution of the solar corona during a CME. Our model of

  17. Levels and Age Dependency of Neurofilament Light and Glial Fibrillary Acidic Protein in Healthy Individuals and Their Relation to the Brain Parenchymal Fraction

    PubMed Central

    Vågberg, Mattias; Norgren, Niklas; Dring, Ann; Lindqvist, Thomas; Birgander, Richard; Zetterberg, Henrik; Svenningsson, Anders

    2015-01-01

    Background Neurofilament light (NFL) and Glial Fibrillary Acidic Protein (GFAP) are integral parts of the axonal and astrocytal cytoskeletons respectively and are released into the cerebrospinal fluid (CSF) in cases of cellular damage. In order to interpret the levels of these biomarkers in disease states, knowledge on normal levels in the healthy is required. Another biomarker for neurodegeneration is brain atrophy, commonly measured as brain parenchymal fraction (BPF) using magnetic resonance imaging (MRI). Potential correlations between levels of NFL, GFAP and BPF in healthy individuals have not been investigated. Objectives To present levels of NFL and GFAP in healthy individuals stratified for age, and investigate the correlation between them as well as their correlation with BPF. Methods The CSF was analysed in 53 healthy volunteers aged 21 to 70 (1 sample missing for GFAP analysis) and 48 of the volunteers underwent determination of BPF using MRI. Results Mean (±SD) NFL was 355 ng/L (±214), mean GFAP was 421 ng/L (±129) and mean BPF was 0.867 (±0.035). All three biomarkers correlated with age. NFL also correlated with both GFAP and BPF. When controlled for age, only the correlation between NFL and GFAP retained statistical significance. Conclusions This study presents data on age-stratified levels of NFL and GFAP in the CSF of healthy individuals. There is a correlation between levels of NFL and GFAP and both increase with age. A correlation between NFL and BPF was also found, but did not retain statistical significance if controlled for age. PMID:26317831

  18. Correlation Between Experimental and Calculated Phase Fractions in Aged 20Cr32Ni1Nb Austenitic Stainless Steels Containing Nitrogen

    NASA Astrophysics Data System (ADS)

    Dewar, Matthew P.; Gerlich, Adrian P.

    2013-02-01

    A centrifugally cast 20Cr32Ni1Nb stainless steel manifold in service for 16 years at temperatures ranging from 1073 K to 1123 K (800 °C to 850 °C) has been characterized using scanning electron microscopy (SEM), electron probe micro-analysis (EPMA), auger electron spectroscopy (AES), and X-ray diffraction (XRD). Nb(C,N), M23C6, and the silicide G-phases (Ni16Nb6Si7) were all identified in a conventional SEM, while the nitride Z-phase (CrNbN) was observed only in AES. M23C6, Z-phase and G-phase were characterized in XRD. Thermodynamic equilibrium calculations using ThermoCalc Version S, with the TCS Steel and Fe-alloys Database (TCFE6), and Thermotech Ni-based Superalloys Database (TTNI8) were validated by comparing experimental phase fraction results obtained from both EPMA and AES. A computational study looking at variations in the chemical composition of the alloy, and how they affect phase equilibria, was investigated. Increasing the nitrogen concentration is shown to decrease G-phase formation, where it is replaced by other intermetallic phases such as Z-phase and π-phase that do not experience liquation during pre-weld annealing treatments. Suppressing G-phase formation was ultimately determined to be a function of minimizing silicon content, and understabilizing the Nb/(C + 6/7N) ratio.

  19. EPISODIC EJECTION FROM ACTIVE ASTEROID 311P/PANSTARRS

    SciTech Connect

    Jewitt, David; Agarwal, Jessica; Weaver, Harold; Mutchler, Max; Larson, Stephen

    2015-01-10

    We examine the development of the active asteroid 311P/PANSTARRS (formerly, 2013 P5) in the period from 2013 September to 2014 February using high resolution images from the Hubble Space Telescope. This multi-tailed object is characterized by a single, reddish nucleus of absolute magnitude H ≥ 18.98 ± 0.10, corresponding to an equal-area sphere of radius ≤200 ± 20 m (for assumed geometric albedo 0.29 ± 0.09). We set an upper limit to the radii of possible companion nuclei at ∼10 m. The nucleus ejected debris in nine discrete episodes, spread irregularly over a nine month interval, each time forming a distinct tail. Particles in the tails range from about 10 μm to at least 80 mm in radius, and were ejected at speeds <1 m s{sup –1}. The ratio of the total ejected dust mass to the nucleus mass is ∼3×10{sup –5}, corresponding to a global surface layer ∼2 mm thick, or to a deeper layer covering a smaller fraction of the surface. The observations are incompatible with an origin of the activity by impact or by the sublimation of entrapped ice. This object appears to be shedding its regolith by rotational (presumably YORP-driven) instability. Long-term fading of the photometry (months) is attributed to gradual dissipation of near-nucleus dust. Photometric variations on short timescales (<0.7 hr) are probably caused by fast rotation of the nucleus. However, because of limited time coverage and dilution of the nucleus signal by near-nucleus dust, we have not been able to determine the rotation period.

  20. Better Visual Outcome by Intraocular Lens Ejection in Geriatric Patients with Ruptured Ocular Injuries

    PubMed Central

    Sugita, Tadasu; Tsunekawa, Taichi; Matsuura, Toshiyuki; Takayama, Kei; Yamamoto, Kentaro; Kachi, Shu; Ito, Yasuki; Ueno, Shinji; Nonobe, Norie; Kataoka, Keiko; Suzumura, Ayana; Iwase, Takeshi; Terasaki, Hiroko

    2017-01-01

    Ocular trauma is one of the leading causes of visual impairment worldwide. Because of the popularity of cataract surgeries, aged individuals with ocular trauma commonly have a surgical wound in their eyes. The purpose of this study was to evaluate the visual outcome of cases that were coincident with intraocular lens (IOL) ejection in the eyes with ruptured open-globe ocular injuries. Consecutive patients with open-globe ocular injuries were first reviewed. Patients’ characteristics, corrected distance visual acuities (CDVAs) over 3 years after the trauma, causes of injuries, traumatic wound patterns, and coexistence of retinal detachment were examined. The relationships between poor CDVA and the other factors, including the complications of crystalline lens and IOL ejection, were examined. A total of 105 eyes/patients [43 eyes with rupture, 33 with penetrating, 28 with intraocular foreign body (IOFB), and 1 with perforating injuries] were included. Rupture injuries were common in aged patients and were mostly caused by falls, whereas penetrating and IOFB injuries were common in young male patients. CDVAs of the eyes with rupture injuries were significantly worse than those of the eyes with penetrating or IOFB injuries. CDVA from more than 50% of the ruptured eyes resulted in no light perception or light perception to 20/500. CDVA of the ruptured eyes complicated by crystalline lens ejection was significantly worse than that of those complicated by IOL ejection. The wounds of the ruptured eyes complicated by IOL ejection were mainly located at the superior corneoscleral limbus, whereas those of the eyes complicated by crystalline lens ejection were located at the posterior sclera. There were significant correlations between poor CDVA and retinal detachment and crystalline lens ejection. These results proposed a new trend in the ocular injuries that commonly occur in aged patients; history of cataract surgery might affect the final visual outcome after open

  1. Electrohydodynamic ejection without using nozzle electrode

    NASA Astrophysics Data System (ADS)

    Dat Nguyen, Vu; Byun, Doyoung

    2009-11-01

    The electrohydrodynamic (EHD) ejection technique has been applied to inkjet printing technology for fabrication of printed electronics. The conventional EHD inkjet device is based on dc voltage and requires two electrodes: a nozzle electrode and an extractor electrode. This study notes several drawbacks of the conventional EHD printing device such as electrical breakdown and demonstrates stable jetting by using the extractor electrode alone without the nozzle electrode and ac voltage. The continuous ejection of droplets can be obtained only by ac voltage, showing consistent ejection at every peak of electrical signal. The suggested EHD inkjet device prevents electrical breakdown and broaden the range of material selection for nozzle design. Experiments with high speed camera also point out that the generated droplets are much smaller than the nozzle size. Using glass capillary, we show various printing patterns of lines and characters.

  2. Coronal mass ejections and coronal structures

    NASA Technical Reports Server (NTRS)

    Hildner, E.; Bassi, J.; Bougeret, J. L.; Duncan, R. A.; Gary, D. E.; Gergely, T. E.; Harrison, R. A.; Howard, R. A.; Illing, R. M. E.; Jackson, B. V.

    1986-01-01

    Research on coronal mass ejections (CMF) took a variety of forms, both observational and theoretical. On the observational side there were: case studies of individual events, in which it was attempted to provide the most complete descriptions possible, using correlative observations in diverse wavelengths; statistical studies of the properties CMEs and their associated activity; observations which may tell us about the initiation of mass ejections; interplanetary observations of associated shocks and energetic particles even observations of CMEs traversing interplanetary space; and the beautiful synoptic charts which show to what degree mass ejections affect the background corona and how rapidly (if at all) the corona recovers its pre-disturbance form. These efforts are described in capsule form with an emphasis on presenting pictures, graphs, and tables so that the reader can form a personal appreciation of the work and its results.

  3. Heritability of white matter microstructure in late middle age: A twin study of tract-based fractional anisotropy and absolute diffusivity indices.

    PubMed

    Vuoksimaa, Eero; Panizzon, Matthew S; Hagler, Donald J; Hatton, Sean N; Fennema-Notestine, Christine; Rinker, Daniel; Eyler, Lisa T; Franz, Carol E; Lyons, Michael J; Neale, Michael C; Tsuang, Ming T; Dale, Anders M; Kremen, William S

    2017-04-01

    There is evidence that differences among individuals in white matter microstructure, as measured with diffusion tensor imaging (DTI), are under genetic control. However, little is known about the relative contribution of genetic and environmental effects on different diffusivity indices among late middle-aged adults. Here, we examined the magnitude of genetic influences for fractional anisotropy (FA), and mean (MD), axial (AD), and radial (RD) diffusivities in male twins aged 56-66 years old. Using an atlas-based registration approach to delineate individual white matter tracts, we investigated mean DTI-based indices within the corpus callosum, 12 bilateral tracts and all these regions of interest combined. All four diffusivity indices had high heritability at the global level (72%-80%). The magnitude of genetic effects in individual tracts varied from 0% to 82% for FA, 0% to 81% for MD, 8% to 77% for AD, and 0% to 80% for RD with most of the tracts showing significant heritability estimates. Despite the narrow age range of this community-based sample, age was correlated with all four diffusivity indices at the global level. In sum, all diffusion indices proved to have substantial heritability for most of the tracts and the heritability estimates were similar in magnitude for different diffusivity measures. Future studies could aim to discover the particular set of genes that underlie the significant heritability of white matter microstructure. Hum Brain Mapp 38:2026-2036, 2017. © 2017 Wiley Periodicals, Inc.

  4. Do we understand coronal mass ejections yet?

    NASA Astrophysics Data System (ADS)

    Hildner, Ernest

    Though many more coronal mass ejections (CMEs) were observed, and though much more has been learned about them during the Solar Maximum Analysis period, they are not yet fully understood. A few recent observational results are reviewed; conclusions and implications drawn from these observations are presented. An emerging picture of the magnetic character of CMEs is sketched; the variations of CMEs' frequency and latitudes over most of a solar cycle are shown. A strong caution about the present lack of concensus on the definition of CMEs is illustrated with examples of the consequences of using different definitions. Finally, some remaining questions about coronal mass ejections are posed.

  5. Halo Coronal Mass Ejections and Geomagnetic Storms

    NASA Technical Reports Server (NTRS)

    Gopalswamy, Nat

    2009-01-01

    In this letter, I show that the discrepancies in the geoeffectiveness of halo coronal mass ejections (CMEs) reported in the literature arise due to the varied definitions of halo CMEs used by different authors. In particular, I show that the low geoeffectiveness rate is a direct consequence of including partial halo CMEs. The geoeffectiveness of partial halo CMEs is lower because they are of low speed and likely to make a glancing impact on Earth. Key words: Coronal mass ejections, geomagnetic storms, geoeffectiveness, halo CMEs.

  6. Bacteriophage P22 ejects all of its internal proteins before its genome.

    PubMed

    Jin, Yan; Sdao, Sophia M; Dover, John A; Porcek, Natalia B; Knobler, Charles M; Gelbart, William M; Parent, Kristin N

    2015-11-01

    Double-stranded DNA bacteriophages are highly pressurized, providing a force driving ejection of a significant fraction of the genome from its capsid. In P22-like Podoviridae, internal proteins ("E proteins") are packaged into the capsid along with the genome, and without them the virus is not infectious. However, little is known about how and when these proteins come out of the virus. We employed an in vitro osmotic suppression system with high-molecular-weight polyethylene glycol to study P22 E protein release. While slow ejection of the DNA can be triggered by lipopolysaccharide (LPS), the rate is significantly enhanced by the membrane protein OmpA from Salmonella. In contrast, E proteins are not ejected unless both OmpA and LPS are present and their ejection when OmpA is present is largely complete before any genome is ejected, suggesting that E proteins play a key role in the early stage of transferring P22 DNA into the host.

  7. The Automatic Detection of Coronal Mass Ejections Using the Solar Mass Ejection Imager

    DTIC Science & Technology

    2009-10-30

    Res., 112, A09103, doi: 10.1029/2007JA012358, 2007. Low, B.C., Solar activity and the corona , Solar Phys. 167, p217, 1996. Robbrecht, E., and D...AFRL-RV-HA-TR-2009-1104 Q- o o o p o The Automatic Detection of Coronal Mass Ejections Using the Solar Mass Ejection Imager Timothy A. Howard... Solar Mass Ejection Imager 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6340IF 6. AUTHORS Timothy A. Howard S. James Tappin

  8. The tectonic significance of K/Ar illite fine-fraction ages from the San Luis Formation (Eastern Sierras Pampeanas, Argentina)

    NASA Astrophysics Data System (ADS)

    Wemmer, Klaus; Steenken, André; Müller, Stefan; de Luchi, Mónica G. López; Siegesmund, Siegfried

    2011-04-01

    The Sierra de San Luis forms the southern tip of the Eastern Sierras Pampeanas in central Argentina. Two narrow belts of low-grade phyllites and quartz arenites, i.e. the San Luis Formation, have accommodated part of the strain-related differential exhumation of the medium- to high-grade metamorphic domains that constitute to the basement complex of the sierra. Eleven phyllite samples were subjected to the K/Ar fine-fraction dating technique. Results are interpreted in relation to the Kübler index of the illites, which indicate epimetamorphic conditions for the majority of the samples. Obtained ages between 330 and 290 Ma cover a period of compressional tectonics in the late Mississippian (Visean/Serpukhovian boundary) followed by the subsidence during the formation of the Paganzo Basin in the provinces of La Rioja and San Luis. These tectonic movements are coincident with the Toco orogeny in northern Chile and southern Bolivia. This suggests that the older K/Ar ages document the compressional stage and that younger ages record the cooling of the basement during the subsequent extensional uplift of the basement.

  9. Do centrioles generate a polar ejection force?

    PubMed

    Wells, Jonathan

    2005-01-01

    A microtubule-dependent polar ejection force that pushes chromosomes away from spindle poles during prometaphase is observed in animal cells but not in the cells of higher plants. Elongating microtubules and kinesin-like motor molecules have been proposed as possible causes, but neither accounts for all the data. In the hypothesis proposed here a polar ejection force is generated by centrioles, which are found in animals but not in higher plants. Centrioles consist of nine microtubule triplets arranged like the blades of a tiny turbine. Instead of viewing centrioles through the spectacles of molecular reductionism and neo-Darwinism, this hypothesis assumes that they are holistically designed to be turbines. Orthogonally oriented centriolar turbines could generate oscillations in spindle microtubules that resemble the motion produced by a laboratory vortexer. The result would be a microtubule-mediated ejection force tending to move chromosomes away from the spindle axis and the poles. A rise in intracellular calcium at the onset of anaphase could regulate the polar ejection force by shutting down the centriolar turbines, but defective regulation could result in an excessive force that contributes to the chromosomal instability characteristic of most cancer cells.

  10. How much dust does Enceladus eject?

    NASA Astrophysics Data System (ADS)

    Kempf, Sascha; Srama, Ralf; Postberg, Frank; Schmidt, Juergen

    2016-07-01

    There is an ongoing argument how much dust per second the ice volcanoes on Saturn's ice moon eject. By adjusting their plume model to the dust flux measured by the Cassini dust detector during the close Enceladus flyby in 2005, Schmidt et al. (2008) obtained a total dust production rate in the plumes of about

  11. Origin of Coronal Shocks without Mass Ejections

    NASA Astrophysics Data System (ADS)

    Shanmugaraju, A.; Moon, Y.-J.; Cho, K.-S.; Dryer, M.; Umapathy, S.

    2006-01-01

    We present an analysis of all the events (around 400) of coronal shocks for which the shock-associated metric type IIs were observed by many spectrographs during the period April 1997 December 2000. The main objective of this analysis is to give evidence for the type IIs related to only flare-blast waves, and thus to find out whether there are any type II-associated coronal shocks without mass ejections. By carefully analyzing the data from multi-wavelength observations (Radio, GOES X-ray, Hα, SOHO/LASCO and SOHO/EIT-EUV data), we have identified only 30 events for which there were actually no reports of CMEs. Then from the analysis of the LASCO and EIT running difference images, we found that there are some shocks (nearly 40%, 12/30) which might be associated with weak and narrow mass ejections. These weak and narrow ejections were not reported earlier. For the remaining 60% events (18/30), there are no mass ejections seen in SOHO/LASCO. But all of them are associated with flares and EIT brightenings. Pre-assuming that these type IIs are related to the flares, and from those flare locations of these 18 cases, 16 events are found to occur within the central region of the solar disk (longitude ≤45^∘). In this case, the weak CMEs originating from this region are unlikely to be detected by SOHO/LASCO due to low scattering. The remaining two events occurred beyond this longitudinal limit for which any mass ejections would have been detected if they were present. For both these events, though there are weak eruption features (EIT dimming and loop displacement) in the EIT images, no mass ejection was seen in LASCO for one event, and a CME appeared very late for the other event. While these two cases may imply that the coronal shocks can be produced without any mass ejections, we cannot deny the strong relationship between type IIs and CMEs.

  12. Electrostatic Droplet Ejection Using Planar Needle Inkjet Head

    NASA Astrophysics Data System (ADS)

    Hakiai, Kazunori; Ishida, Yuji; Baba, Akiyoshi; Asano, Tanemasa

    2005-07-01

    For the purpose of investigating the electrostatic droplet ejection event, a planar needle inkjet head with a projected cone-shaped needle (3-D head) was prepared to observe the phenomenon of droplet ejection. As the initial approach to developing a liquid ejection monitoring method, electric current was also measured. The ejection was found to take place as a series of single events that are composed of fine droplet ejections forming the Taylor cone and the subsequent swing back of the liquid front owing to the relationship between surface tension and electrostatic force. The critical factors for ejecting fine droplets in the case of using the inkjet head having a protruding needle were back pressure from the reservoir and the wetting control of the structures. The fast Fourier transform of electric current revealed the appearance of periodic signals during ejection, which may be used in developing a technique of sensing droplet ejection.

  13. 49 CFR 571.226 - Standard No. 226; Ejection Mitigation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    .... Target means the x-z plane projection of the ejection headform face as shown in Figure 1. Walk-in van... the ejection headform when the headform is aligned with an impact target location and just touching... propels the ejection impactor into the impact target locations of each side daylight opening of a...

  14. Coronal Mass Ejections - A Statistical View

    NASA Technical Reports Server (NTRS)

    SaintCyr, O. C.; Cremades, H.

    2008-01-01

    Although first recognized in 1971, the quasi-continuous record since 1979 of the appearance of coronal mass ejections (CMEs-perhaps more appropriately called coronal magnetic ejections) has resulted in a stable understanding of their properties, at least from a statistical viewpoint. These eruptions occur every few days during solar activity minimum and many times per day during maximum. They are believed to play an important role throughout the heliosphere in such diverse events as removing helicity from the corona; modulating the energetic particle environment in the inner heliosphere; causing severe geomagnetic storms at Earth and other magnetic bodies throughout the solar system; and controlling the galactic cosmic ray flux. It is therefore understandable that researchers have studied both individual events and the ensemble of CMEs observed over several solar cycles. We will present an overview of these statistics, some new recent observations, and a personal perspective on potential paths of future research.

  15. MHD shocks in coronal mass ejections

    NASA Technical Reports Server (NTRS)

    Steinolfson, R. S.

    1991-01-01

    The primary objective of this research program is the study of the magnetohydrodynamic (MHD) shocks and nonlinear simple waves produced as a result of the interaction of ejected lower coronal plasma with the ambient corona. The types of shocks and nonlinear simple waves produced for representative coronal conditions and disturbance velocities were determined. The wave system and the interactions between the ejecta and ambient corona were studied using both analytic theory and numerical solutions of the time-dependent, nonlinear MHD equations. Observations from the SMM coronagraph/polarimeter provided both guidance and motivation and are used extensively in evaluating the results. As a natural consequence of the comparisons with the data, the simulations assisted in better understanding the physical interactions in coronal mass ejections (CME's).

  16. Ejection safety for advanced fighter helmets

    NASA Astrophysics Data System (ADS)

    Wiley, Larry L.; Brown, Randall W.; MacMillan, Robert T.

    1995-05-01

    The old saying, `Safety is paramount.' was never more true than it is in the area of ejection safety for high-speed fighter aircraft. The fighter aircraft of today has been designed to endure tremendous structural loading during dogfight or evasive maneuvers. It can fly faster, turn quicker, stay in the air longer (with in-flight refuel) and carry more bombs than its predecessor. Because of human physiological limits, the human has become the weak link in today's fighter aircraft. The fighter pilot must endure and function with peak performance in conditions that are much worse than anything the majority of us will ever encounter. When these conditions reach a point that human endurance is exceeded, devices such as anti-g suits and positive pressure breathing apparatus help the fighter pilot squeeze out that extra percentage of strength necessary to outperform the opponent. As fighter aircraft become more sophisticated, helmet trackers, helmet displays and noise cancellation devices are being added to the helmet. Yet the fighter pilot's helmet must remain lightweight and be aesthetically appealing, while still offering ballistic protection. It must function with existing life support equipment such as the Combined Advanced Technology Enhanced Design g-Ensemble (COMBAT-EDGE). It must not impede the pilot's ability to perform any action necessary to accomplish the planned mission. The helmet must protect the pilot during the harsh environment of ejection. When the pilot's only resort is to pull the handle and initiate the ejection sequence, the helmet becomes his salvation or instant death. This paper discusses the safety concerns relative to the catapult phase of ejecting from a high-speed fighter while wearing an advanced fighter helmet.

  17. Ejectable underwater sound source recovery assembly

    NASA Technical Reports Server (NTRS)

    Irick, S. C. (Inventor)

    1974-01-01

    An underwater sound source is described that may be ejectably mounted on any mobile device that travels over water, to facilitate in the location and recovery of the device when submerged. A length of flexible line maintains a connection between the mobile device and the sound source. During recovery, the sound source is located be particularly useful in the recovery of spent rocket motors that bury in the ocean floor upon impact.

  18. Potential Method of Predicting Coronal Mass Ejection

    NASA Astrophysics Data System (ADS)

    Imholt, Timothy

    2001-10-01

    Coronal Mass Ejections (CME) may be described as a blast of gas and highly charged solar mass fragments ejected into space. These ejections, when directed toward Earth, have many different effects on terrestrial systems ranging from the Aurora Borealis to changes in wireless communication. The early prediction of these solar events cannot be overlooked. There are several models currently accepted and utilized to predict these events, however, with earlier prediction of both the event and the location on the sun where the event occurs allows us to have earlier warnings as to when they will affect man-made systems. A better prediction could perhaps be achieved by utilizing low angular resolution radio telescope arrays to catalog data from the sun at different radio frequencies on a regular basis. Once this data is cataloged a better predictor for these CME’s could be found. We propose a model that allows a prediction to be made that appears to be longer than 24 hours.

  19. Potential Method of Predicting Coronal Mass Ejection

    NASA Astrophysics Data System (ADS)

    Imholt, Timothy; Roberts, J. A.; Scott, J. B.; University Of North Texas Team

    2000-10-01

    Coronal Mass Ejections (CME) may be described as a blast of gas and highly charged solar mass fragments ejected into space. These ejections, when directed toward Earth, have many different effects on terrestrial systems ranging from the Aurora Borealis to changes in wireless communications. The importance of an early prediction of these solar events cannot be overlooked. There are several models currently accepted and utilized to predict these events, however, with earlier prediction of both the event and the location on the sun where the event occur allows us to have earlier warnings as to when they will effect man-made systems. A better prediction could perhaps be achieved by utilizing low angular resolution radio telescope arrays to catalog data from the sun at different radio frequencies on a regular basis. Once this data is cataloged a better predictor for these CME's could be found. We propose a model that allows a prediction to be made that appears to be longer than 24 hours.

  20. Membrane-assisted viral DNA ejection.

    PubMed

    Santos-Pérez, Isaac; Oksanen, Hanna M; Bamford, Dennis H; Goñi, Felix M; Reguera, David; Abrescia, Nicola G A

    2017-03-01

    Genome packaging and delivery are fundamental steps in the replication cycle of all viruses. Icosahedral viruses with linear double-stranded DNA (dsDNA) usually package their genome into a preformed, rigid procapsid using the power generated by a virus-encoded packaging ATPase. The pressure and stored energy due to this confinement of DNA at a high density is assumed to drive the initial stages of genome ejection. Membrane-containing icosahedral viruses, such as bacteriophage PRD1, present an additional architectural complexity by enclosing their genome within an internal membrane vesicle. Upon adsorption to a host cell, the PRD1 membrane remodels into a proteo-lipidic tube that provides a conduit for passage of the ejected linear dsDNA through the cell envelope. Based on volume analyses of PRD1 membrane vesicles captured by cryo-electron tomography and modeling of the elastic properties of the vesicle, we propose that the internal membrane makes a crucial and active contribution during infection by maintaining the driving force for DNA ejection and countering the internal turgor pressure of the host. These novel functions extend the role of the PRD1 viral membrane beyond tube formation or the mere physical confinement of the genome. The presence and assistance of an internal membrane might constitute a biological advantage that extends also to other viruses that package their linear dsDNA to high density within an internal vesicle.

  1. Topological friction strongly affects viral DNA ejection

    PubMed Central

    Marenduzzo, Davide; Micheletti, Cristian; Orlandini, Enzo; Sumners, De Witt

    2013-01-01

    Bacteriophages initiate infection by releasing their double-stranded DNA into the cytosol of their bacterial host. However, what controls and sets the timescales of DNA ejection? Here we provide evidence from stochastic simulations which shows that the topology and organization of DNA packed inside the capsid plays a key role in determining these properties. Even with similar osmotic pressure pushing out the DNA, we find that spatially ordered DNA spools have a much lower effective friction than disordered entangled states. Such spools are only found when the tendency of nearby DNA strands to align locally is accounted for. This topological or conformational friction also depends on DNA knot type in the packing geometry and slows down or arrests the ejection of twist knots and very complex knots. We also find that the family of (2, 2k+1) torus knots unravel gradually by simplifying their topology in a stepwise fashion. Finally, an analysis of DNA trajectories inside the capsid shows that the knots formed throughout the ejection process mirror those found in gel electrophoresis experiments for viral DNA molecules extracted from the capsids. PMID:24272939

  2. Long-term use of deferiprone significantly enhances left-ventricular ejection function in thalassemia major patients.

    PubMed

    Maggio, Aurelio; Vitrano, Angela; Lucania, Gaetano; Capra, Marcello; Cuccia, Liana; Gagliardotto, Francesco; Pitrolo, Lorella; Prossomariti, Luciano; Filosa, Aldo; Caruso, Vincenzo; Gerardi, Calogera; Campisi, Saveria; Cianciulli, Paolo; Rizzo, Michele; D'Ascola, Giuseppe; Ciancio, Angela; Di Maggio, Rosario; Calvaruso, Giuseppina; Pantalone, Gaetano Restivo; Rigano, Paolo

    2012-07-01

    A multicenter randomized open-label long-term sequential deferiprone–deferoxamine (DFP-DFO) versus DFP alone trial (sequential DFP-DFO) performed in patients with thalassemia major (TM) was retrospectively reanalyzed to assess the variation in the left ventricular ejection fraction (LVEF) [1].

  3. Relation between Flare-associated X-Ray Ejections and Coronal Mass Ejections.

    PubMed

    Nitta; Akiyama

    1999-11-01

    In an attempt to identify the direct signatures of coronal mass ejections (CMEs) in soft X-ray wavelengths, we have searched for plasma ejections in Yohkoh soft X-ray telescope (SXT) images in a total of 17 limb flares, and compared the results with the Solar and Heliospheric Observatory LASCO data. A general correlation exists between the presence/absence of the X-ray ejection and the CME. Although the height versus time relation often indicates (under the assumption of constant speed) that the CME onset coincides with the X-ray ejection, the latter probably does not represent the CME front, because the CME speed must result from acceleration, which would put the estimated onset at an earlier time. In some cases, the estimated CME onset time comes well before the impulsive phase of the associated flare. Although the role of the flare-associated plasma ejection in a CME is still unclear, we propose that its occurrence depends on the presence of open field lines, which can be due to a preceding CME. Lastly, we present a rare example of SXT observations of what appeared to be the three-part structure of a CME, which was seen a few minutes before a major flare started.

  4. Aging

    PubMed Central

    Park, Dong Choon

    2013-01-01

    Aging is initiated based on genetic and environmental factors that operate from the time of birth of organisms. Aging induces physiological phenomena such as reduction of cell counts, deterioration of tissue proteins, tissue atrophy, a decrease of the metabolic rate, reduction of body fluids, and calcium metabolism abnormalities, with final progression onto pathological aging. Despite the efforts from many researchers, the progression and the mechanisms of aging are not clearly understood yet. Therefore, the authors would like to introduce several theories which have gained attentions among the published theories up to date; genetic program theory, wear-and-tear theory, telomere theory, endocrine theory, DNA damage hypothesis, error catastrophe theory, the rate of living theory, mitochondrial theory, and free radical theory. Although there have been many studies that have tried to prevent aging and prolong life, here we introduce a couple of theories which have been proven more or less; food, exercise, and diet restriction. PMID:24653904

  5. The distribution of ejected brown dwarfs in clusters

    NASA Astrophysics Data System (ADS)

    Goodwin, S. P.; Hubber, D. A.; Moraux, E.; Whitworth, A. P.

    2005-12-01

    We examine the spatial distribution of brown dwarfs produced by the decay of small-N stellar systems as expected from the embryo ejection scenario. We model a cluster of several hundred stars grouped into 'cores' of a few stars/brown dwarfs. These cores decay, preferentially ejecting their lowest-mass members. Brown dwarfs are found to have a wider spatial distribution than stars, however once the effects of limited survey areas and unresolved binaries are taken into account it can be difficult to distinguish between clusters with many or no ejections. A large difference between the distributions probably indicates that ejections have occurred, however similar distributions sometimes arise even with ejections. Thus the spatial distribution of brown dwarfs is not necessarily a good discriminator between ejection and non-ejection scenarios.

  6. Role of osmotic and hydrostatic pressures in bacteriophage genome ejection

    NASA Astrophysics Data System (ADS)

    Lemay, Serge G.; Panja, Debabrata; Molineux, Ian J.

    2013-02-01

    A critical step in the bacteriophage life cycle is genome ejection into host bacteria. The ejection process for double-stranded DNA phages has been studied thoroughly in vitro, where after triggering with the cellular receptor the genome ejects into a buffer. The experimental data have been interpreted in terms of the decrease in free energy of the densely packed DNA associated with genome ejection. Here we detail a simple model of genome ejection in terms of the hydrostatic and osmotic pressures inside the phage, a bacterium, and a buffer solution or culture medium. We argue that the hydrodynamic flow associated with the water movement from the buffer solution into the phage capsid and further drainage into the bacterial cytoplasm, driven by the osmotic gradient between the bacterial cytoplasm and culture medium, provides an alternative mechanism for phage genome ejection in vivo; the mechanism is perfectly consistent with phage genome ejection in vitro.

  7. Fractional randomness

    NASA Astrophysics Data System (ADS)

    Tapiero, Charles S.; Vallois, Pierre

    2016-11-01

    The premise of this paper is that a fractional probability distribution is based on fractional operators and the fractional (Hurst) index used that alters the classical setting of random variables. For example, a random variable defined by its density function might not have a fractional density function defined in its conventional sense. Practically, it implies that a distribution's granularity defined by a fractional kernel may have properties that differ due to the fractional index used and the fractional calculus applied to define it. The purpose of this paper is to consider an application of fractional calculus to define the fractional density function of a random variable. In addition, we provide and prove a number of results, defining the functional forms of these distributions as well as their existence. In particular, we define fractional probability distributions for increasing and decreasing functions that are right continuous. Examples are used to motivate the usefulness of a statistical approach to fractional calculus and its application to economic and financial problems. In conclusion, this paper is a preliminary attempt to construct statistical fractional models. Due to the breadth and the extent of such problems, this paper may be considered as an initial attempt to do so.

  8. Tract-specific fractional anisotropy predicts cognitive outcome in a community sample of middle-aged participants with white matter lesions

    PubMed Central

    Soriano-Raya, Juan José; Miralbell, Júlia; López-Cancio, Elena; Bargalló, Núria; Arenillas, Juan Francisco; Barrios, Maite; Cáceres, Cynthia; Toran, Pere; Alzamora, Maite; Dávalos, Antoni; Mataró, Maria

    2014-01-01

    Cerebral white matter lesions (WMLs) have been consistently related to cognitive dysfunction but the role of white matter (WM) damage in cognitive impairment is not fully determined. Diffusion tensor imaging is a promising tool to explain impaired cognition related to WMLs. We investigated the separate association of high-grade periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWMHs) with fractional anisotropy (FA) in middle-aged individuals. We also assessed the predictive value to cognition of FA within specific WM tracts associated with high-grade WMLs. One hundred participants from the Barcelona-AsIA Neuropsychology Study were divided into groups based on low- and high-grade WMLs. Voxel-by-voxel FA were compared between groups, with separate analyses for high-grade PVHs and DWMHs. The mean FA within areas showing differences between groups was extracted in each tract for linear regression analyses. Participants with high-grade PVHs and participants with high-grade DWMHs showed lower FA in different areas of specific tracts. Areas showing decreased FA in high-grade DWMHs predicted lower cognition, whereas areas with decreased FA in high-grade PVHs did not. The predictive value to cognition of specific WM tracts supports the involvement of cortico-subcortical circuits in cognitive deficits only in DWMHs. PMID:24549185

  9. Structural and dynamic features of geoeffective coronal ejections

    NASA Astrophysics Data System (ADS)

    Minasyants, G. S.; Minasyants, T. M.

    2011-12-01

    The structure and physical conditions in 104 coronal mass ejections (CMEs) with a clear-cut leading shock front have been considered using satellite data for 1996-2008. In 99% of cases, the action of increased shock front dynamic pressure on the Earth's magnetosphere resulted in the origination of geomagnetic storms with sudden commencement. It has been revealed that decreased magnetic field strength values correspond to denser plasma bunches in an ejection body and vice versa. As a result, gas pressure is decreased in regions with increased magnetic pressure. Thus, a self-consistent interrelationship between plasma parameters, which supports total pressure at mutual changes in gas and magnetic pressures, is observed in the ejection structure. Pronounced differences in variations in the physical parameters in different zones along the front in the Earth-Sun direction have not been detected for each ejection. The maximal distances between the compared ejection zones are 2 million kilometers. This indicates that the ejection structure is stable. The values of the shock front velocity ( V psf), temperature ( T psf), and density ( N psf), as well as the ejection geometrical extension ( L ae), have been compared for the considered ejections. Cases when ejections followed one another at intervals of 3-30 h have been studied. It has been established that a leading ejection is strongly decelerated during its motion, and the next ejection faster covers the distance to the Earth. The next ejections with larger values of the plasma physical parameters are more geoeffective as compared to the previous ejections.

  10. Genesis Solar Wind Interstream, Coronal Hole and Coronal Mass Ejection Samples: Update on Availability and Condition

    NASA Technical Reports Server (NTRS)

    Allton, J. H.; Gonzalez, C. P.; Allums, K. K.

    2017-01-01

    Recent refinement of analysis of ACE/SWICS data (Advanced Composition Explorer/Solar Wind Ion Composition Spectrometer) and of onboard data for Genesis Discovery Mission of 3 regimes of solar wind at Earth-Sun L1 make it an appropriate time to update the availability and condition of Genesis samples specifically collected in these three regimes and currently curated at Johnson Space Center. ACE/SWICS spacecraft data indicate that solar wind flow types emanating from the interstream regions, from coronal holes and from coronal mass ejections are elementally and isotopically fractionated in different ways from the solar photosphere, and that correction of solar wind values to photosphere values is non-trivial. Returned Genesis solar wind samples captured very different kinds of information about these three regimes than spacecraft data. Samples were collected from 11/30/2001 to 4/1/2004 on the declining phase of solar cycle 23. Meshik, et al is an example of precision attainable. Earlier high precision laboratory analyses of noble gases collected in the interstream, coronal hole and coronal mass ejection regimes speak to degree of fractionation in solar wind formation and models that laboratory data support. The current availability and condition of samples captured on collector plates during interstream slow solar wind, coronal hole high speed solar wind and coronal mass ejections are de-scribed here for potential users of these samples.

  11. Particle Ejection and Levitation Technology (PELT)

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Each of the six Apollo landers touched down at unique sites on the lunar surface. Aside from the Apollo 12 landing site located 180 meters from the Surveyor III lander, plume impingement effects on ground hardware during the landings were not a problem. The planned return to the Moon requires numerous landings at the same site. Since the top few centimeters of lunar soil are loosely packed regolith, plume impingement from the lander will eject the granular material at high velocities. A picture shows what the astronauts viewed from the window of the Apollo 14 lander. There was tremendous dust excavation beneath the vehicle. With high-vacuum conditions on the Moon (10 (exp -14) to 10 (exp -12) torr), motion of all particles is completely ballistic. Estimates derived from damage to Surveyor III caused by the Apollo 12 lander show that the speed of the ejected regolith particles varies from 100 m/s to 2,000 m/s. It is imperative to understand the physics of plume impingement to safely design landing sites for future Moon missions. Aerospace scientists and engineers have examined and analyzed images from Apollo video extensively in an effort to determine the theoretical effects of rocket exhaust impingement. KSC has joined the University of Central Florida (UCF) to develop an instrument that will measure the 3-D vector of dust flow caused by plume impingement during descent of landers. The data collected from the instrument will augment the theoretical studies and analysis of the Apollo videos.

  12. Energetics of solar coronal mass ejections

    NASA Astrophysics Data System (ADS)

    Subramanian, P.; Vourlidas, A.

    2007-05-01

    Aims:We investigate whether solar coronal mass ejections are driven mainly by coupling to the ambient solar wind or through the release of internal magnetic energy. Methods: We examine the energetics of 39 flux-rope like coronal mass ejections (CMEs) from the Sun using data in the distance range ~2-20 R⊙ from the Large Angle Spectroscopic Coronograph (LASCO) aboard the Solar and Heliospheric Observatory (SOHO). This comprises a complete sample of the best examples of flux-rope CMEs observed by LASCO in 1996-2001. Results: We find that 69% of the CMEs in our sample experience a clearly identifiable driving power in the LASCO field of view. For those CMEs that are driven, we examine if they might be deriving most of their driving power by coupling to the solar wind. We do not find conclusive evidence in favor of this hypothesis. On the other hand, we find that their internal magnetic energy is a viable source of the required driving power. We have estimated upper and lower limits on the power that can possibly be provided by the internal magnetic field of a CME. We find that, on average, the lower limit to the available magnetic power is around 74% of what is required to drive the CMEs, while the upper limit can be as much as an order of magnitude larger.

  13. Global Response to Local Ionospheric Mass Ejection

    NASA Technical Reports Server (NTRS)

    Moore, T. E.; Fok, M.-C.; Delcourt, D. C.; Slinker, S. P.; Fedder, J. A.

    2010-01-01

    We revisit a reported "Ionospheric Mass Ejection" using prior event observations to guide a global simulation of local ionospheric outflows, global magnetospheric circulation, and plasma sheet pressurization, and comparing our results with the observed global response. Our simulation framework is based on test particle motions in the Lyon-Fedder-Mobarry (LFM) global circulation model electromagnetic fields. The inner magnetosphere is simulated with the Comprehensive Ring Current Model (CRCM) of Fok and Wolf, driven by the transpolar potential developed by the LFM magnetosphere, and includes an embedded plasmaspheric simulation. Global circulation is stimulated using the observed solar wind conditions for the period 24-25 Sept 1998. This period begins with the arrival of a Coronal Mass Ejection, initially with northward, but later with southward interplanetary magnetic field. Test particles are launched from the ionosphere with fluxes specified by local empirical relationships of outflow to electrodynamic and particle precipitation imposed by the MIlD simulation. Particles are tracked until they are lost from the system downstream or into the atmosphere, using the full equations of motion. Results are compared with the observed ring current and a simulation of polar and auroral wind outflows driven globally by solar wind dynamic pressure. We find good quantitative agreement with the observed ring current, and reasonable qualitative agreement with earlier simulation results, suggesting that the solar wind driven global simulation generates realistic energy dissipation in the ionosphere and that the Strangeway relations provide a realistic local outflow description.

  14. Drop Ejection From an Oscillating Rod

    NASA Technical Reports Server (NTRS)

    Wilkes, E. D.; Basaran, O. A.

    1999-01-01

    The dynamics of a drop of a Newtonian liquid that is pendant from or sessile on a solid rod that is forced to undergo time-periodic oscillations along its axis is studied theoretically. The free boundary problem governing the time evolution of the shape of the drop and the flow field inside it is solved by a method of lines using a finite element algorithm incorporating an adaptive mesh. When the forcing amplitude is small, the drop approaches a limit cycle at large times and undergoes steady oscillations thereafter. However, drop breakup is the consequence if the forcing amplitude exceeds a critical value. Over a wide range of amplitudes above this critical value, drop ejection from the rod occurs during the second oscillation period from the commencement of rod motion. Remarkably, the shape of the interface at breakup and the volume of the primary drop formed are insensitive to changes in forcing amplitude. The interface shape at times close to and at breakup is a multi-valued function of distance measured along the rod axis and hence cannot be described by recently popularized one-dimensional approximations. The computations show that drop ejection occurs without the formation of a long neck. Therefore, this method of drop formation holds promise of preventing formation of undesirable satellite droplets.

  15. MEMEX: Mechanisms of Energetic Mass Ejection Explorer

    NASA Astrophysics Data System (ADS)

    Moore, T. E.; Chappell, C. R.; Clemmons, J. H.; Cully, C. M.; Donovan, E.; Earle, G. D.; Heelis, R. A.; Kistler, L. M.; Kepko, L.; Khazanov, G. V.; Knudsen, D. J.; Lessard, M.; McFadden, J. P.; Nicolls, M. J.; Pollock, C. J.; Pfaff, R. F.; Rankin, R.; Rowland, D. E.; Semeter, J. L.; Thayer, J. P.; Winglee, R.

    2013-12-01

    MEMEX is designed to find out how gravitationally-trapped volatile matter is being lost from atmospheres by energetic processes, depleting them of key constituents, as has occurred most dramatically at Mars. This process is exemplified in geospace by the dissipation of solar energy to produce ionospheric outflows that feed back on dynamics of the solar wind interaction with Earth's magnetosphere. Kinetic and electromagnetic energy flow from the Sun into the coupled (auroral) ionosphere, where resultant electron, ion, and gas heating give rise to upwelling, ionization, and mass ejection. Proposed mechanisms involve wave-particle heating interactions, upward ambipolar electric fields, or ponderomotive forces. A large number of free energy sources have been identified, but empirical guidance remains weak concerning their relative importance. Moreover, it is unclear if the waves interact with particles primarily in a cyclotron resonant mode, or in a lower hybrid exchange of electron (parallel) and ion (perpendicular) energy, or in a bulk ponderomotive mode. MEMEX will answer the questions raised by these issues: Where do the waves that produce mass ejection grow? How do they propagate and transport energy? How can wave amplitudes, heating, and escape rates be derived from solar wind conditions? Is the heating a cyclotron resonant process or a bulk ponderomotive forcing process? To obtain answers, MEMEX will for the first time simultaneously observe the magnetospheric and atmospheric boundary conditions applied to the topside or exobase layer, and the response of ions and electrons to the ensuing battle between electrodynamic forcing and collisional damping.

  16. Space probe/satellite ejection apparatus for spacecraft

    NASA Technical Reports Server (NTRS)

    Smyly, H. M.; Miller, C. D.; Cloyd, R. A.; Heller, C. (Inventor)

    1984-01-01

    An ejection apparatus for spinning and propelling objects for ejection from a spacecraft at a desired velocity and rotational speed is discussed. The apparatus includes a launch cradle on which the space object to be ejected rests. The cradle is rotatably supported by a central hub secured to the upper end of the pneumatic cylinder piston shaft. Release mechanisms consisting of a retractable pin and locking lug is utilized to hold the cradle and object to be ejected. The release mechanism has a fixed barrier member which holds the retractable pin in engagement with the locking lug until release by upward movement of the launch cradle beyond the barrier height.

  17. Space probe/satellite ejection apparatus for spacecraft

    NASA Technical Reports Server (NTRS)

    Smyly, H. M.; Miller, C. D.; Cloyd, R. A.; Heller, C. (Inventor)

    1985-01-01

    An ejection apparatus for spinning and propelling objects for ejection from a spacecraft at a desired velocity and rotational speed is discussed. The apparatus includes a launch cradle on which the space object to be ejected rests. The cradle is rotatably supported by a central hub secured to the upper end of the pneumatic cylinder piston shaft. Release mechanisms consisting of a retractable pin and locking lug is utilized to hold the cradle and object to be ejected. The release mechanism has a fixed barrier member which holds the retractable pin in engagement with the locking lug until release by upward movement of the launch cradle beyond the barrier height.

  18. Acoustic and aerodynamic characteristics of ejectives in Amharic

    NASA Astrophysics Data System (ADS)

    Demolin, Didier

    2004-05-01

    This paper invetsigates the main phonetic characteristics that distinguishes ejectives from pulmonic sounds in Amharic. In this language, there are five ejectives that can be phonemically singleton or geminate. Duration measurements have been made in intervocalic position for pulmonic stops and for each type of ejective, taking into account the overall duration and VOT. Results show that ejective stops have a higher amplitude burst than pulmonic stops. The duration of the noise is shorter for ejective fricatives compared to pulmonic fricatives. At the end of ejective fricatives, there is a 30-ms glottal lag that is not present in pulmonic fricatives. Geminate ejectives are realized by delaying the elevation of the larynx. This can be observed on the spectrographic data by an increase of the noise at the end of the geminate ejectives. Aerodynamic data have been collected in synchronization with the acoustic recordings. The main observations are that pharyngeal pressures values are much higher than what is usually assumed (up to 40 CmH2O for velars) and that the delayed command in the elevation of the larynx of geminate ejectives is shown by two phases in the rise of pharyngeal pressure.

  19. Coronal Mass Ejections: From Sun to Earth

    NASA Astrophysics Data System (ADS)

    Patsourakos, S.

    2016-06-01

    Coronal Mass Ejections (CMEs) are gigantic expulsions of magnetized plasmas from the solar corona into the interplanetary (IP) space. CMEs spawn ~ 1015 gr of mass and reach speeds ranging between several hundred to a few thousand km/s (e.g., Gopalswamy et al. 2009; Vourlidas et al. 2010). It takes 1-5 days for a CME to reach Earth. CMEs are one of the most energetic eruptive manifestations in the solar system and are major drivers of space weather via their magnetic fields and energetic particles, which are accelerated by CME-driven shocks. In this review we give a short account of recent, mainly observational, results on CMEs from the STEREO and SDO missions which include the nature of their pre-eruptive and eruptive configurations and the CME propagation from Sun to Earth. We conclude with a discussion of the exciting capabilities in CME studies that will soon become available from new solar and heliospheric instrumentation.

  20. Geometrical Properties of Coronal Mass Ejections

    NASA Astrophysics Data System (ADS)

    Cremades, Hebe; Bothmer, Volker

    Based on the SOHO/LASCO dataset, a collection of "structured" coronal mass ejections (CMEs) has been compiled within the period 1996-2002, in order to analyze their three-dimensional configuration. These CME events exhibit white-light fine structures, likely indicative of their possible 3D topology. From a detailed investigation of the associated low coronal and photospheric source regions, a generic scheme has been deduced, which considers the white-light topology of a CME projected in the plane of the sky as being primarily dependent on the orientation and position of the source region's neutral line on the solar disk. The obtained results imply that structured CMEs are essentially organized along a symmetry axis, in a cylindrical manner. The measured dimensions of the cylinder's base and length yield a ratio of 1.6. These CMEs seem to be better approximated by elliptic cones, rather than by the classical ice cream cone, characterized by a circular cross section.

  1. Solar Eruptions: Coronal Mass Ejections and Flares

    NASA Technical Reports Server (NTRS)

    Gopalswamy, Nat

    2012-01-01

    This lecture introduces the topic of Coronal mass ejections (CMEs) and solar flares, collectively known as solar eruptions. During solar eruptions, the released energy flows out from the Sun in the form of magnetized plasma and electromagnetic radiation. The electromagnetic radiation suddenly increases the ionization content of the ionosphere, thus impacting communication and navigation systems. Flares can be eruptive or confined. Eruptive flares accompany CMEs, while confined flares hav only electromagnetic signature. CMEs can drive MHD shocks that accelerate charged particles to very high energies in the interplanetary space, which pose radiation hazard to astronauts and space systems. CMEs heading in the direction of Earth arrive in about two days and impact Earth's magnetosphere, producing geomagnetic storms. The magnetic storms result in a number of effects including induced currnts that can disrupt power grids, railroads, and underground pipelines

  2. Boulders Ejected From Small Impact Craters

    NASA Astrophysics Data System (ADS)

    Bart, Gwendolyn D.; Melosh, H. J.

    2006-09-01

    We investigate the distribution of boulders ejected from lunar craters by analyzing high resolution Lunar Orbiter images. Our previous study (DPS 2004) of four small craters indicated that larger boulders are more frequently found close to the crater rim rather than far away, and that the size of the ejecta drops off as a power law with distance from the crater. Our current study adds more than ten new bouldery craters that range in size from 200 m to several kilometers and are found on a variety of terrain (mare, highlands, and the Copernicus ejecta blanket.) For each crater we plot the boulder diameter as a function of the ejection velocity of the boulder. We compare this size-velocity distribution with the size-velocity distribution of ejecta from large craters (Vickery 1986, 1987) to ascertain the mechanism of fracture of the substrate in the impact. We also make cumulative plots of the boulders, indicating the number of boulders of each size present around the crater. The cumulative plots allow us to compare our boulder distributions with the distributions of secondary craters from large impacts. Material thrown from a several-hundred-meter diameter crater may land intact as boulders, but material thrown from a tens-of-kilometers diameter crater will travel at a significantly higher velocity, and will form a secondary crater when it impacts the surface. Our data helps elucidate whether the upturn, at small diameters, of the cratering curve of the terrestrial planets is due to secondary impacts or to the primary population. This work is funded by NASA PGG grant NNG05GK40G.

  3. Ejection of Supernova-Enriched Gas From Dwarf Disk Galaxies

    SciTech Connect

    Fragile, P C; Murray, S D; Lin, D C

    2004-06-15

    We examine the efficiency with which supernova-enriched gas may be ejected from dwarf disk galaxies, using a methodology previously employed to study the self-enrichment efficiency of dwarf spheroidal systems. Unlike previous studies that focused on highly concentrated starbursts, in the current work we consider discrete supernova events spread throughout various fractions of the disk. We model disk systems having gas masses of 10{sup 8} and 10{sup 9} M{sub {circle_dot}} with supernova rates of 30, 300, and 3000 Myr{sup -1}. The supernova events are confined to the midplane of the disk, but distributed over radii of 0, 30, and 80% of the disk radius, consistent with expectations for Type II supernovae. In agreement with earlier studies, we find that the enriched material from supernovae is largely lost when the supernovae are concentrated near the nucleus, as expected for a starburst event. In contrast, we find the loss of enriched material to be much less efficient (as low as 21%) when the supernovae occur over even a relatively small fraction of the disk. The difference is due to the ability of the system to relax following supernova events that occur over more extended regions. Larger physical separations also reduce the likelihood of supernovae going off within low-density ''chimneys'' swept out by previous supernovae. We also find that, for the most distributed systems, significant metal loss is more likely to be accompanied by significant mass loss. A comparison with theoretical predications indicates that, when undergoing self-regulated star formation, galaxies in the mass range considered shall efficiently retain the products of Type II supernovae.

  4. Tracking Coronal Mass Ejections with a Heliospheric Imager: Case Studies from the Solar Mass Ejection Imager

    NASA Astrophysics Data System (ADS)

    Johnston, J. C.; Mizuno, D. R.; Webb, D. F.; Kuchar, T. A.; Howard, T. A.

    2005-05-01

    The Solar Mass Ejection Imager (SMEI) was launched on board the DoD Space Test Program's Coriolis satellite in January 2003. Two-thirds through its planned 3-year lifetime, SMEI has observed Coronal Mass Ejections (CMEs), comets and asteroids as they move through the heliosphere. More than 140 CMEs have been detected with the SMEI instrument, including well-documented "halo" events that led to geomagnetic storm conditions on Earth. These observations demonstrate the potential of a heliospheric imager for space weather specification and prediction purposes. We present several case studies of CMEs as they propagate through the SOHO LASCO and SMEI fields of view, and examine SMEI's "hit" rate for detection of geoeffective CMEs.

  5. An ejection model for SNC meteorites: An indication for recent volcanism on Mars

    NASA Technical Reports Server (NTRS)

    Manker, J. P.

    1992-01-01

    When compared to other achondrites, Shergotty-Nakhla-Chassigny (SNC) meteorites are viewed as anomalous objects. This conclusion is based mainly on their extremely young crystallization ages and their short cosmic ray exposure times. Further, SNC's noble gas and nitrogen components indicate a martian origin for these objects. If these meteorites are from Mars, then the most confounding question facing the planetary science community is how were they ejected from the planet's surface. The following is an investigation of that question.

  6. Fighter Pilot Ejection Study as an Educational Tool

    ERIC Educational Resources Information Center

    Robinson, Garry; Jovanoski, Zlatko

    2010-01-01

    In this article, we apply the well-known equations of projectile motion to the case of a fighter pilot ejecting from an aircraft, the aim being to establish under what conditions there is danger of impact with the rear vertical stabilizer. The drag force on the pilot after ejection is assumed to vary as the velocity squared and the aircraft motion…

  7. Calculation of momentum distribution of positronium ejected from surfaces

    SciTech Connect

    Shindo, S.; Ishii, A.

    1987-07-01

    The two-dimensional momentum distribution of positronium formed and ejected from a surface is calculated and compared with experimental results. It is shown that the higher-order Born contribution is very important for explaining the experimental momentum distributions of positronium ejected from the surface.

  8. A simultaneous spin/eject mechanism for aerospace payloads

    NASA Technical Reports Server (NTRS)

    Palmer, G. D.; Banks, T. N.

    1976-01-01

    A simultaneous spin/eject mechanism was developed for aerospace applications requiring a compact, passive device which would accommodate payload support and controlled-release functions, and which would provide a highly accurate spin-ejection motion to the payload. The mechanism satisfied the requirements and is adaptable to other deployment applications.

  9. Understanding Multiplication of Fractions.

    ERIC Educational Resources Information Center

    Sweetland, Robert D.

    1984-01-01

    Discussed the use of Cuisenaire rods in teaching the multiplication of fractions. Considers whole number times proper fraction, proper fraction multiplied by proper fraction, mixed number times proper fraction, and mixed fraction multiplied by mixed fractions. (JN)

  10. Status of the Solar Mass Ejection Imager

    NASA Astrophysics Data System (ADS)

    Johnston, J. C.; Radick, R. R.; Webb, D. F.

    2001-05-01

    The Solar Mass Ejection Imager (SMEI) is a proof-of-concept experiment designed to detect and track coronal mass ejections (CMEs) as they propagate from the Sun through interplanetary space to the Earth and beyond. SMEI will Image CMEs by sensing sunlight scattered from the free electrons in these structures (Thomson scattering). SMEI will be launched by a Titan II rocket into a circular, sun-synchronous (830 km) orbit in 2002 as part of the Space Test Program's CORIOLIS mission. SMEI will image the entire sky once per spacecraft orbit over a mission lifetime of three years. The major subsystems of SMEI are three electronic camera assemblies and a data-handling unit. Each camera consists of a baffle, a radiator, a bright object sensor, an electronics box, and a strongbox containing a shutter, optics and a CCD. Each camera images a 3x60 degree field. Together, they view a 180-degree slice of sky, and sweep over the entire sky once per orbit. SMEI's basic data product will be a 100-minute cadence of all-sky maps of heliospheric brightness, with stars removed, having an angular resolution of about one degree and a photometric precision of about 0.1%. Successful operation of SMEI will represent a major step in improving space weather forecasts. When combined with in-situ solar wind measurements from upstream monitors such as WIND and ACE, SMEI will provide one- to three-day predictions of impending geomagnetic storms at the Earth. SMEI will complement missions such as SoHO, GOES SXI, Solar-B, and STEREO by providing data relating solar drivers to terrestrial effects. Other benefits of SMEI will include observations of variable stars, extra-Solar planetary transits, novae and supernovae, comets and asteroids. The SMEI experiment is being designed and constructed by a team of scientists and engineers from the Air Force Research Laboratory, the University of Birmingham (UB) in the United Kingdom, the University of California at San Diego (UCSD), and Boston University. The

  11. Detection of coronal mass ejections using AdaBoost on grayscale statistic features

    NASA Astrophysics Data System (ADS)

    Zhang, Ling; Yin, Jian-qin; Lin, Jia-ben; Wang, Xiao-fan; Guo, Juan

    2016-10-01

    We present an automatic algorithm to detect coronal mass ejections (CMEs) in Large Angle Spectrometric Coronagraph (LASCO) C2 running difference images. The algorithm includes 3 steps: (1) split the running difference images into blocks according to slice size and analyze the grayscale statistics of the blocks from a set of images with and without CMEs; (2) select the optimal parameters for slice size, gray threshold and fraction of the bright points and (3) use AdaBoost to combine the weak classifiers designed according to the optimal parameters. Experimental results show that our method is effective and has a high accuracy rate.

  12. Left ventricular ejection time, not heart rate, is an independent correlate of aortic pulse wave velocity.

    PubMed

    Salvi, Paolo; Palombo, Carlo; Salvi, Giovanni Matteo; Labat, Carlos; Parati, Gianfranco; Benetos, Athanase

    2013-12-01

    Several studies showed a positive association between heart rate and pulse wave velocity, a sensitive marker of arterial stiffness. However, no study involving a large population has specifically addressed the dependence of pulse wave velocity on different components of the cardiac cycle. The aim of this study was to explore in subjects of different age the link between pulse wave velocity with heart period (the reciprocal of heart rate) and the temporal components of the cardiac cycle such as left ventricular ejection time and diastolic time. Carotid-femoral pulse wave velocity was assessed in 3,020 untreated subjects (1,107 men). Heart period, left ventricular ejection time, diastolic time, and early-systolic dP/dt were determined by carotid pulse wave analysis with high-fidelity applanation tonometry. An inverse association was found between pulse wave velocity and left ventricular ejection time at all ages (<25 years, r(2) = 0.043; 25-44 years, r(2) = 0.103; 45-64 years, r(2) = 0.079; 65-84 years, r(2) = 0.044; ≥ 85 years, r(2) = 0.022; P < 0.0001 for all). A significant (P < 0.0001) negative but always weaker correlation between pulse wave velocity and heart period was also found, with the exception of the youngest subjects (P = 0.20). A significant positive correlation was also found between pulse wave velocity and dP/dt (P < 0.0001). With multiple stepwise regression analysis, left ventricular ejection time and dP/dt remained the only determinant of pulse wave velocity at all ages, whereas the contribution of heart period no longer became significant. Our data demonstrate that pulse wave velocity is more closely related to left ventricular systolic function than to heart period. This may have methodological and pathophysiological implications.

  13. Filament Eruption without Coronal Mass Ejection

    NASA Technical Reports Server (NTRS)

    Choudhary, Debi Prasad; Moore, Ronald L.

    2003-01-01

    We report characteristics of quiescent filament eruptions that were not associated with coronal mass ejections (CMEs). We examined 12 quiescent filament eruptions, each of which was located far from disk center (20.7 R(sub sun)) in diffuse remnant magnetic fields of decayed active regions, was well observed in full-disk movies in Ha and Fe XI, and had good coronagraph coverage. Of the 12 events, 9 were associated with CMEs and 3 were not. Even though the two kinds of eruption were indistinguishable in their magnetic setting and in the eruptive motion of the filament in the Ha movies, each of the CME-producing eruptions produced a two-ribbon flare in Ha and a coronal arcade and/or two-ribbon flare in Fe XII, and each of the non-CME-producing eruptions did not. From this result, and the appearance of the eruptive motion in the Fe XII movies, we conclude that the non-CME-associated filament eruptions are confined eruptions like the confined filament eruptions in active regions.

  14. A model for stealth coronal mass ejections

    NASA Astrophysics Data System (ADS)

    Lynch, B. J.; Masson, S.; Li, Y.; DeVore, C. R.; Luhmann, J. G.; Antiochos, S. K.; Fisher, G. H.

    2016-11-01

    Stealth coronal mass ejections (CMEs) are events in which there are almost no observable signatures of the CME eruption in the low corona but often a well-resolved slow flux rope CME observed in the coronagraph data. We present results from a three-dimensional numerical magnetohydrodynamics (MHD) simulation of the 1-2 June 2008 slow streamer blowout CME that Robbrecht et al. (2009) called "the CME from nowhere." We model the global coronal structure using a 1.4 MK isothermal solar wind and a low-order potential field source surface representation of the Carrington Rotation 2070 magnetogram synoptic map. The bipolar streamer belt arcade is energized by simple shearing flows applied in the vicinity of the helmet streamer's polarity inversion line. The flows are large scale and impart a shear typical of that expected from the differential rotation. The slow expansion of the energized helmet streamer arcade results in the formation of a radial current sheet. The subsequent onset of expansion-induced flare reconnection initiates the stealth CME while gradually releasing the stored magnetic energy. We present favorable comparisons between our simulation results and the multiviewpoint SOHO-LASCO (Large Angle and Spectrometric Coronagraph) and STEREO-SECCHI (Sun Earth Connection Coronal and Heliospheric Investigation) coronagraph observations of the preeruption streamer structure and the initiation and evolution of the stealth streamer blowout CME.

  15. Kinematical properties of coronal mass ejections

    NASA Astrophysics Data System (ADS)

    Temmer, M.

    2016-11-01

    Coronal mass ejections (CMEs) are the most dynamic phenomena in our solar system. They abruptly disrupt the continuous outflow of solar wind by expelling huge clouds of magnetized plasma into interplanetary space with velocities enabling to cross the Sun-Earth distance within a few days. Earth-directed CMEs may cause severe geomagnetic storms when their embedded magnetic fields and the shocks ahead compress and reconnect with the Earth's magnetic field. The transit times and impacts in detail depend on the initial CME velocity, size, and mass, as well as on the conditions and coupling processes with the ambient solar wind flow in interplanetary space. The observed CME parameters may be severely affected by projection effects and the constant changing environmental conditions are hard to derive. This makes it difficult to fully understand the physics behind CME evolution, preventing to do a reliable forecast of Earth-directed events. This short review focusing on observational data, shows recent methods which were developed to derive the CME kinematical profile for the entire Sun-Earth distance range as well as studies which were performed to shed light on the physical processes that CMEs encounter when propagating from Sun to Earth.

  16. Solar origins of coronal mass ejections

    NASA Technical Reports Server (NTRS)

    Kahler, Stephen

    1987-01-01

    The large scale properties of coronal mass ejections (CMEs), such as morphology, leading edge speed, and angular width and position, have been cataloged for many events observed with coronagraphs on the Skylab, P-78, and SMM spacecraft. While considerable study has been devoted to the characteristics of the SMEs, their solar origins are still only poorly understood. Recent observational work has involved statistical associations of CMEs with flares and filament eruptions, and some evidence exists that the flare and eruptive-filament associated CMEs define two classes of events, with the former being generally more energetic. Nevertheless, it is found that eruptive-filament CMEs can at times be very energetic, giving rise to interplanetary shocks and energetic particle events. The size of the impulsive phase in a flare-associated CME seems to play no significant role in the size or speed of the CME, but the angular sizes of CMEs may correlate with the scale sizes of the 1-8 angstrom x-ray flares. At the present time, He 10830 angstrom observations should be useful in studying the late development of double-ribbon flares and transient coronal holes to yield insights into the CME aftermath. The recently available white-light synoptic maps may also prove fruitful in defining the coronal conditions giving rise to CMEs.

  17. Slow shocks in coronal mass ejections

    NASA Technical Reports Server (NTRS)

    Steinolfson, R. S.

    1989-01-01

    The possibility that slow-mode shock compression may produce at least some of the increased brightness observed at the leading edge of coronal mass ejections is investigated. Among the reasons given for the possible existence of slow shocks are the following: (1) transient velocities are often greater than the upstream sound speed but less than the Alfven speed, (2) the presence of a slow shock is consistent with the flat top observed in some transients, and (3) the lateral extension of slow shocks may be responsible for distributing adjacent structures as also seen on the observations. It is shown that there may be some difficulties with this suggestion for transients originating inside the closed-field region at the base of a preexisting coronal streamer. First of all, slow mode characteristics have difficulty emerging from the closed-field region at the streamer base so they can merge to form a slow shock, unless a preceding, large-amplitude disturbance opens the field lines. In addition, a slow shock cannot exist at the center of the streamer current sheet. Finally, numerical simulations demonstrate that at least the last two (and possibly all) of the above reasons for slow shocks can be satisfied by a disturbance whose leading edge propagates at the local fast-mode speed without any shocks. The leading portion of the transient that would be seen in white-light coronagraphs propagates at a speed either less than or equal to the fast-mode speed.

  18. Coronal Mass Ejections and Solar Radio Emissions

    NASA Technical Reports Server (NTRS)

    Gopalswamy, Nat

    2010-01-01

    Coronal mass ejections (CMEs) have important connections to various types of radio emissions from the Sun. The persistent noise storm radiation (type I storm at metric wavelengths, type III storms at longer wavelengths) can be clearly interrupted by the occurrence of a CME in the active region that produces the storm. Sometimes the noise storm completely disappears and other times, it reappears in the active region. Long-lasting type III bursts are associated with CME eruption, thought to be due to the reconnection process taking place beneath the erupting CME. Type II bursts are indicative of electron acceleration in the CME-driven shocks and hence considered to be the direct response of the CME propagation in the corona and interplanetary medium. Finally type IV bursts indicate large-scale post-eruption arcades containing trapped electrons that produce radio emission. This paper summarizes some key results that connect CMEs to various types of radio emission and what we can learn about particle acceleration in the corona) and interplanetary medium. Particular emphasis will be placed on type If bursts because of their connection to interplanetary shocks detected in situ.

  19. Particle Heating Resulting from Coronal Mass Ejection

    NASA Astrophysics Data System (ADS)

    Paul, Suman; Sundar De, Syam; Guha, Gautam

    2016-07-01

    Coronal Mass Ejection (CME) is a continuous phenomena occurring from the entire solar coronal zone responsible for the outflow of solar masses, viz., protons, electrons, neutrons and solar wind in the form of plasma. These perturb the Earth's atmosphere via magnetopause. Very high temperature plasma generator in the solar atmosphere produces huge magnetic dipoles with intense magnetic field. It traps the energetic charged particles released from the solar corona. These particles gyrate along the magnetic field lines and are gradually elongated outwards from the Sun. Due to this, the field lines get detached at some critical limit thereby enhancing the magnetic reconnection with the interplanetary magnetic field releasing huge energy in the form of X-rays and γ-rays. This perturbs the Earth's atmosphere. In this work, the situation has been investigated by momentum balance equation, energy balance equation along with the equations of continuity and states. From the analyses, the dispersive nature of the thermospheric medium is studied. Variation of normalized electron temperature with dimensionless time has been critically contemplated. The altitude dependent electric field in the medium is also investigated.

  20. EIT Observations of Coronal Mass Ejections

    NASA Technical Reports Server (NTRS)

    Gurman, J. B.; Fisher, Richard B. (Technical Monitor)

    2000-01-01

    Before the Solar and Heliospheric Observatory (SOHO), we had only the sketchiest of clues as to the nature and topology of coronal mass ejections (CMEs) below 1.1 - 1.2 solar radii. Occasionally, dimmings (or 'transient coronal holes') were observed in time series of soft X-ray images, but they were far less frequent than CME's. Simply by imaging the Sun frequently and continually at temperatures of 0.9 - 2.5 MK we have stumbled upon a zoo of CME phenomena in this previously obscured volume of the corona: (1) waves, (2) dimmings, and (3) a great variety of ejecta. In the three and a half years since our first observations of coronal waves associated with CME's, combined Large Angle Spectroscopic Coronagraph (LASCO) and extreme ultra-violet imaging telescope (EIT) synoptic observations have become a standard prediction tool for space weather forecasters, but our progress in actually understanding the CME phenomenon in the low corona has been somewhat slower. I will summarize the observations of waves, hot (> 0.9 MK) and cool ejecta, and some of the interpretations advanced to date. I will try to identify those phenomena, analysis of which could most benefit from the spectroscopic information available from ultraviolet coronograph spectrometer (UVCS) observations.

  1. Thermodynamic MHD Modeling of Coronal Mass Ejections

    NASA Astrophysics Data System (ADS)

    Linker, Jon A.; Lionello, R.; Mikic, Z.; Riley, P.; Titov, V.

    2007-05-01

    Coronal mass ejections (CMEs) disrupt the large-scale coronal magnetic field and propel plasma and magnetic flux outward into interplanetary space. The most energetic CMEs typically originate from active regions on the Sun. Accurately modeling active regions while also capturing the entire corona requires MHD models that include energy transport (radiative losses,anisotropic thermal conduction, and coronal heating) in the transition region and solar corona. We refer to this as the thermodynamic MHD model. The more accurate representation of energy flow in the thermodynamic MHD model allows us to to compute simulated EUV and X-ray emission as would be observed from spacecraft such as SOHO, STEREO, and Hinode. With this approach, theorists no longer get to argue what emission they think their favorite model's magnetic field evolution implies; we can actually go compute the emission and compare with observations. As an example, we show a simulation of the May 12, 1997 CME, and compare the simulated emission with observations from the actual event of dimming regions, postflare loops, and reformation of loops near the northern polar coronal hole. Work supported by NASA, NSF and the Center for Integrated Space Weather Modeling (an NSF Science and Technology Center).

  2. Anatomy of Depleted Interplanetary Coronal Mass Ejections

    NASA Astrophysics Data System (ADS)

    Kocher, M.; Lepri, S. T.; Landi, E.; Zhao, L.; Manchester, W. B., IV

    2017-01-01

    We report a subset of interplanetary coronal mass ejections (ICMEs) containing distinct periods of anomalous heavy-ion charge state composition and peculiar ion thermal properties measured by ACE/SWICS from 1998 to 2011. We label them “depleted ICMEs,” identified by the presence of intervals where C6+/C5+ and O7+/O6+ depart from the direct correlation expected after their freeze-in heights. These anomalous intervals within the depleted ICMEs are referred to as “Depletion Regions.” We find that a depleted ICME would be indistinguishable from all other ICMEs in the absence of the Depletion Region, which has the defining property of significantly low abundances of fully charged species of helium, carbon, oxygen, and nitrogen. Similar anomalies in the slow solar wind were discussed by Zhao et al. We explore two possibilities for the source of the Depletion Region associated with magnetic reconnection in the tail of a CME, using CME simulations of the evolution of two Earth-bound CMEs described by Manchester et al.

  3. Dynamic simulation of coronal mass ejections

    NASA Technical Reports Server (NTRS)

    Steinolfson, R. S.; Wu, S. T.

    1980-01-01

    A model is developed for the formation and propagation through the lower corona of the loop-like coronal transients in which mass is ejected from near the solar surface to the outer corona. It is assumed that the initial state for the transient is a coronal streamer. The initial state for the streamer is a polytropic, hydrodynamic solution to the steady-state radial equation of motion coupled with a force-free dipole magnetic field. The numerical solution of the complete time-dependent equations then gradually approaches a stationary coronal streamer configuration. The streamer configuration becomes the initial state for the coronal transient. The streamer and transient simulations are performed completely independent of each other. The transient is created by a sudden increase in the pressure at the base of the closed-field region in the streamer configuration. Both coronal streamers and coronal transients are calculated for values of the plasma beta (the ratio of thermal to magnetic pressure) varying from 0.1 to 100.

  4. Why are halo coronal mass ejections faster?

    NASA Astrophysics Data System (ADS)

    Zhang, Qing-Min; Guo, Yang; Chen, Peng-Fei; Ding, Ming-De; Fang, Cheng

    2010-05-01

    Halo coronal mass ejections (CMEs) have been to be significantly faster than normal CMEs, which is a long-standing puzzle. In order to solve the puzzle, we first investigate the observed properties of 31 limb CMEs that clearly display loop-shaped frontal loops. The observational results show a strong tendency that slower CMEs are weaker in white-light intensity. Then, we perform a Monte Carlo simulation of 20000 artificial limb CMEs that have an average velocity of ~523 km s-1. The Thomson scattering of these events is calculated when they are assumed to be observed as limb and halo events, respectively. It is found that the white-light intensity of many slow CMEs becomes remarkably reduced when they turn from being viewed as a limb event to being viewed as a halo event. When the intensity is below the background solar wind fluctuation, it is assumed that they would be missed by coronagraphs. The average velocity of “detectable" halo CMEs is ~922 km s-1 very close to the observed value. This also indicates that wider events are more likely to be recorded. The results soundly suggest that the higher average velocity of halo CMEs is due to that a majority of slow events and some of narrow fast events carrying less material are so faint that they are blended with the solar wind fluctuations, and therefore are not observed.

  5. Active Longitude and Coronal Mass Ejection Occurrences

    NASA Astrophysics Data System (ADS)

    Gyenge, N.; Singh, T.; Kiss, T. S.; Srivastava, A. K.; Erdélyi, R.

    2017-03-01

    The spatial inhomogeneity of the distribution of coronal mass ejection (CME) occurrences in the solar atmosphere could provide a tool to estimate the longitudinal position of the most probable CME-capable active regions in the Sun. The anomaly in the longitudinal distribution of active regions themselves is often referred to as active longitude (AL). In order to reveal the connection between the AL and CME spatial occurrences, here we investigate the morphological properties of active regions. The first morphological property studied is the separateness parameter, which is able to characterize the probability of the occurrence of an energetic event, such as a solar flare or CME. The second morphological property is the sunspot tilt angle. The tilt angle of sunspot groups allows us to estimate the helicity of active regions. The increased helicity leads to a more complex buildup of the magnetic structure and also can cause CME eruption. We found that the most complex active regions appear near the AL and that the AL itself is associated with the most tilted active regions. Therefore, the number of CME occurrences is higher within the AL. The origin of the fast CMEs is also found to be associated with this region. We concluded that the source of the most probably CME-capable active regions is at the AL. By applying this method, we can potentially forecast a flare and/or CME source several Carrington rotations in advance. This finding also provides new information for solar dynamo modeling.

  6. Evidence linking coronal mass ejections with interplanetary magnetic clouds

    NASA Technical Reports Server (NTRS)

    Wilson, R. M.; Hildner, E.

    1983-01-01

    Using proxy data for the occurrence of those mass ejections from the solar corona which are directed earthward, we investigate the association between the post-1970 interplanetary magnetic clouds of Klein and Burlaga and coronal mass ejections. The evidence linking magnetic clouds following shocks with coronal mass ejections is striking; six of nine clouds observed at Earth were preceded an appropriate time earlier by meter-wave type II radio bursts indicative of coronal shock waves and coronal mass ejections occurring near central meridian. During the selected periods when no clouds were detected near Earth, the only type II bursts reported were associated with solar activity near the limbs. Where the proxy solar data to be sought are not so clearly suggested, that is, for clouds preceding interaction regions and clouds within cold magnetic enhancements, the evidence linking the clouds and coronal mass ejections is not as clear; proxy data usually suggest many candidate mass-ejection events for each cloud. Overall, the data are consistent with and support the hypothesis suggested by Klein and Burlaga that magnetic clouds observed with spacecraft at 1 AU are manifestations of solar coronal mass ejection transients.

  7. Magnetohydrodynamic simulations of the ejection of a magnetic flux rope

    NASA Astrophysics Data System (ADS)

    Pagano, P.; Mackay, D. H.; Poedts, S.

    2013-06-01

    Context. Coronal mass ejections (CME's) are one of the most violent phenomena found on the Sun. One model to explain their occurrence is the flux rope ejection model. In this model, magnetic flux ropes form slowly over time periods of days to weeks. They then lose equilibrium and are ejected from the solar corona over a few hours. The contrasting time scales of formation and ejection pose a serious problem for numerical simulations. Aims: We simulate the whole life span of a flux rope from slow formation to rapid ejection and investigate whether magnetic flux ropes formed from a continuous magnetic field distribution, during a quasi-static evolution, can erupt to produce a CME. Methods: To model the full life span of magnetic flux ropes we couple two models. The global non-linear force-free field (GNLFFF) evolution model is used to follow the quasi-static formation of a flux rope. The MHD code ARMVAC is used to simulate the production of a CME through the loss of equilibrium and ejection of this flux rope. Results: We show that the two distinct models may be successfully coupled and that the flux rope is ejected out of our simulation box, where the outer boundary is placed at 2.5 R⊙. The plasma expelled during the flux rope ejection travels outward at a speed of 100 km s-1, which is consistent with the observed speed of CMEs in the low corona. Conclusions: Our work shows that flux ropes formed in the GNLFFF can lead to the ejection of a mass loaded magnetic flux rope in full MHD simulations. Coupling the two distinct models opens up a new avenue of research to investigate phenomena where different phases of their evolution occur on drastically different time scales. Movies are available in electronic form at http://www.aanda.org

  8. Mystery Fractions

    ERIC Educational Resources Information Center

    Bhattacharyya, Sonalee; Namakshi, Nama; Zunker, Christina; Warshauer, Hiroko K.; Warshauer, Max

    2016-01-01

    Making math more engaging for students is a challenge that every teacher faces on a daily basis. These authors write that they are constantly searching for rich problem-solving tasks that cover the necessary content, develop critical-thinking skills, and engage student interest. The Mystery Fraction activity provided here focuses on a key number…

  9. Pitch Fractionation.

    DTIC Science & Technology

    1981-12-15

    13 3. Solvent Fractionation Experiments .................................... 15 4. Fourier Transform Infrared Spectra for A240 Petrolem Pitch AG 12...34 and Mesophase Pitch AG 164B ............................... 21 5. Fourier Transform Infrared Spectra ................................... 23 6...compared by Fourier transform infrared (FTIR) analysis using a Digilab Model FTS 14 spectrophotometer (Rockwell International, Anaheim, California

  10. ROTATION OF CORONAL MASS EJECTIONS DURING ERUPTION

    SciTech Connect

    Lynch, B. J.; Li, Y.; Luhmann, J. G.; Antiochos, S. K.; DeVore, C. R. E-mail: yanli@ssl.berkeley.edu E-mail: spiro.k.antiochos@nasa.gov

    2009-06-01

    Understanding the connection between coronal mass ejections (CMEs) and their interplanetary counterparts (ICMEs) is one of the most important problems in solar-terrestrial physics. We calculate the rotation of erupting field structures predicted by numerical simulations of CME initiation via the magnetic breakout model. In this model, the initial potential magnetic field has a multipolar topology and the system is driven by imposing a shear flow at the photospheric boundary. Our results yield insight on how to connect solar observations of the orientation of the filament or polarity inversion line (PIL) in the CME source region, the orientation of the CME axis as inferred from coronagraph images, and the ICME flux rope orientation obtained from in situ measurements. We present the results of two numerical simulations that differ only in the direction of the applied shearing motions (i.e., the handedness of the sheared-arcade systems and their resulting CME fields). In both simulations, eruptive flare reconnection occurs underneath the rapidly expanding sheared fields transforming the ejecta fields into three-dimensional flux rope structures. As the erupting flux ropes propagate through the low corona (from 2 to 4 R{sub sun}) the right-handed breakout flux rope rotates clockwise and the left-handed breakout flux rope rotates counterclockwise, in agreement with recent observations of the rotation of erupting filaments. We find that by 3.5 R {sub sun} the average rotation angle between the flux rope axes and the active region PIL is approximately 50 deg. We discuss the implications of these results for predicting, from the observed chirality of the pre-eruption filament and/or other properties of the CME source region, the direction and amount of rotation that magnetic flux rope structures will experience during eruption. We also discuss the implications of our results for CME initiation models.

  11. How much dust does Enceladus eject?

    NASA Astrophysics Data System (ADS)

    Kempf, Sascha; Horanyi, Mihaly; Schmidt, Jürgen; Southworth, Ben

    2015-04-01

    There is an ongoing argument how much dust per second the ice volcanoes on Saturn's ice moon Enceladus eject. By adjusting their plume model to the dust flux measured by the Cassini dust detector during the close Enceladus flyby in 2005, as well as to the plume brightness in Cassini imaging, Schmidt et al. (2008) obtained a total dust production rate in the plumes of about 5 kg/s. On the other hand, Ingersoll and Ewald (2011) derived a dust production rate of 51 kg/s from photometry of very high phase-angle images of the plume, a method that is sensitive also to particles in the size range of microns and larger. Knowledge of the production rate is essential for estimating the dust to gas mass ratio, which in turn is an important constraint for finding the plume source mechanism. Here we report on numerical simulations of the Enceladus dust plume. We run a large number of dynamical simulations including gravity and Lorentz force to investigate the earliest phase of the ring particle life span. The magnetic field in the vicinity of Enceladus is based on the model by Simon et al. (2012). The evolution of the electrostatic charge carried by the initially uncharged grains is treated self-consistently. Our numerical simulations reproduce dust measurements by the Cassini Cosmic Dust Analyzer (CDA) during Cassini plume traversals as well as the snowfall pattern derived from ISS observations of the Enceladus surface (Schenk et al, 2011, EPSC abstract). Based on our simulation results we are able to draw conclusions about the dust production rate as well as wether the Enceladus dust plume constitutes a dusty plasma.

  12. Pilot Fullerton dons ejection escape suit (EES) on middeck

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Pilot Fullerton dons ejection escape suit (EES) (high altitude pressure garment) life preserver unit (LPU) on forward port side of middeck above potable water tank. Fullerton also adjusts lapbelt fitting and helmet holddown strap.

  13. Particle ejection during mergers of dark matter halos

    SciTech Connect

    Carucci, Isabella P.; Sparre, Martin; Hansen, Steen H.; Joyce, Michael E-mail: sparre@dark-cosmology.dk E-mail: joyce@lpnhe.in2p3.fr

    2014-06-01

    Dark matter halos are built from accretion and merging. During merging some of the dark matter particles may be ejected with velocities higher than the escape velocity. We use both N-body simulations and single-particle smooth-field simulations to demonstrate that rapid changes to the mean field potential are responsible for such ejection, and in particular that dynamical friction plays no significant role in it. Studying a range of minor mergers, we find that typically between 5–15% of the particles from the smaller of the two merging structures are ejected. We also find that the ejected particles originate essentially from the small halo, and more specifically are particles in the small halo which pass later through the region in which the merging occurs.

  14. Mass ejected by impacts with materials of various strengths

    SciTech Connect

    Canavan, G.H.

    1997-02-01

    Similarity solutions are used to discuss impacts on asteroids of various strengths, concentrating on the voids produced, the mass ejected, and its thermodynamic and mechanical state. Numerical calculations have advantages and limitations for the next step in complexity.

  15. Fraction Reduction through Continued Fractions

    ERIC Educational Resources Information Center

    Carley, Holly

    2011-01-01

    This article presents a method of reducing fractions without factoring. The ideas presented may be useful as a project for motivated students in an undergraduate number theory course. The discussion is related to the Euclidean Algorithm and its variations may lead to projects or early examples involving efficiency of an algorithm.

  16. Radio-Loud Coronal Mass Ejections Without Shocks Near Earth

    NASA Technical Reports Server (NTRS)

    Gopalswamy, N.; SaintCyr, O. C.; MacDowall, R. J.; Kaiser, M. L.; Xie, H.; Makela, P.; Akiyama, S.

    2010-01-01

    Type II radio bursts are produced by low energy electrons accelerated in shocks driven by corona) mass ejections (CMEs). One can infer shocks near the Sun, in the Interplanetary medium, and near Earth depending on the wavelength range in which the type II bursts are produced. In fact, type II bursts are good indicators of CMEs that produce solar energetic particles. If the type 11 burst occurs from a source on the Earth-facing side of the solar disk, it is highly likely that a shock arrives at Earth in 2-3 days and hence can be used to predict shock arrival at Earth. However, a significant fraction of CMEs producing type II bursts were not associated shocks at Earth, even though the CMEs originated close to the disk center. There are several reasons for the lack of shock at 1 AU. CMEs originating at large central meridian distances (CMDs) may be driving a shock, but the shock may not be extended sufficiently to reach to the Sun-Earth line. Another possibility is CME cannibalism because of which shocks merge and one observes a single shock at Earth. Finally, the CME-driven shock may become weak and dissipate before reaching 1 AU. We examined a set of 30 type II bursts observed by the Wind/WAVES experiment that had the solar sources very close to the disk center (within a CMD of 15 degrees), but did not have shock at Earth. We find that the near-Sun speeds of the associated CMEs average to approx.600 km/s, only slightly higher than the average speed of CMEs associated with radio-quiet shocks. However, the fraction of halo CMEs is only approx.28%, compared to 40% for radio-quiet shocks and 72% for all radio-loud shocks. We conclude that the disk-center radio loud CMEs with no shocks at 1 AU are generally of lower energy and they drive shocks only close to the Sun.

  17. Models of material ejection. [of solar coronal mass

    NASA Technical Reports Server (NTRS)

    Steinolfson, R. S.

    1990-01-01

    Some recently developed models related to the formation of a coronal mass ejection (CME) are reviewed. The models individually consider the stability of a prominence, the eruption of a coupled prominence and CME configuration with driven reconnection below the prominence, magnetic arcade equilibrium, and coronal evolution due to shear motion. No effort is made to critique the various models. Their relevance to actual observed material ejections will ultimately be determined by detailed comparison with present and future observations.

  18. Isotope fractionation

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    A rash of new controversy has emerged around the subject of mass-independent isotope fractionation effects, particularly in the case of the oxygen isotopes. To be sure, the controversy has been around for awhile, but it has been given new impetus by the results of a recent study by Mark H. Thiemens and John E. Heidenreich III of the University of California, San Diego (Science, March 4, 1983).Gustav Arrhenius has been trying to convince the planetary science community that chemical effects in isotope fractionation processes could explain observations in meteorites that appear to be outside of the traditionally understood mass-dependent fractionations (G. Arrhenius, J . L. McCrumb, and N. F. Friedman, Astrophys. Space Sci, 65, 297, 1974). Robert Clayton had made the basic observations of oxygen in carbonaceous chondrites that the slope of the δ17 versus δ18 line was 1 instead of the slope of ½ characteristic of terrestrial rocks and lunar samples (Ann. Rev. Nucl. Part. Sci., 28, 501, 1978). The mass-independent effects were ascribed to the apparent contribution of an ancient presolar system component of O16.

  19. Chromospheric Plasma Ejections in a Light Bridge of a Sunspot

    NASA Astrophysics Data System (ADS)

    Song, Donguk; Chae, Jongchul; Yurchyshyn, Vasyl; Lim, Eun-Kyung; Cho, Kyung-Suk; Yang, Heesu; Cho, Kyuhyoun; Kwak, Hannah

    2017-02-01

    It is well-known that light bridges (LBs) inside a sunspot produce small-scale plasma ejections and transient brightenings in the chromosphere, but the nature and origin of such phenomena are still unclear. Utilizing the high-spatial and high-temporal resolution spectral data taken with the Fast Imaging Solar Spectrograph and the TiO 7057 Å broadband filter images installed at the 1.6 m New Solar Telescope of Big Bear Solar Observatory, we report arcsecond-scale chromospheric plasma ejections (1.″7) inside a LB. Interestingly, the ejections are found to be a manifestation of upwardly propagating shock waves as evidenced by the sawtooth patterns seen in the temporal-spectral plots of the Ca ii 8542 Å and Hα intensities. We also found a fine-scale photospheric pattern (1″) diverging with a speed of about 2 km s‑1 two minutes before the plasma ejections, which seems to be a manifestation of magnetic flux emergence. As a response to the plasma ejections, the corona displayed small-scale transient brightenings. Based on our findings, we suggest that the shock waves can be excited by the local disturbance caused by magnetic reconnection between the emerging flux inside the LB and the adjacent umbral magnetic field. The disturbance generates slow-mode waves, which soon develop into shock waves, and manifest themselves as the arcsecond-scale plasma ejections. It also appears that the dissipation of mechanical energy in the shock waves can heat the local corona.

  20. An Experimental Investigation of Vibration-Induced Single Droplet Ejection.

    NASA Astrophysics Data System (ADS)

    Range, Kai; Smith, Marc K.; Glezer, Ari

    1998-11-01

    Vibration-induced droplet atomization occurs when small secondary droplets are ejected from the free surface of a larger droplet placed on a vibrating membrane. To model a single ejection event, a liquid droplet is placed on a small piston and vibrated using an electromagnetic driver. The droplet oscillates in a characteristic mode shape that depends on the driving frequency and amplitude, the properties of the liquid, and the size of the droplet. When the excitation amplitude is large enough, a small secondary droplet is ejected from the primary droplet. Observations of this process using high-speed digital video imaging show that droplet ejection occurs when a small liquid column or jet appears on the primary droplet and a secondary droplet forms on the column by a capillary-pinching mechanism. The liquid column or jet emanates from a crater in the primary droplet. As the driving frequency increases, this crater becomes smaller and the diameter of the ejected droplet decreases. We shall present results showing how the ejected droplet diameter and speed depends on the driving frequency and amplitude, the liquid properties, and the primary droplet volume.

  1. The Search for Stellar Coronal Mass Ejections

    NASA Astrophysics Data System (ADS)

    Villadsen, Jacqueline; Hallinan, Gregg; Monroe, Ryan; Bourke, Stephen; Starburst Program Team

    2017-01-01

    Coronal mass ejections (CMEs) may dramatically impact habitability and atmospheric composition of planets around magnetically active stars, including young solar analogs and many M dwarfs. Theoretical predictions of such effects are limited by the lack of observations of stellar CMEs. My thesis addresses this gap through a search for the spectral and spatial radio signatures of CMEs on active M dwarfs.Solar CMEs produce radio bursts with a distinctive spectral signature, narrow-band plasma emission that drifts to lower frequency as a CME expands outward. To search for analogous events on nearby stars, I worked on system design, software, and commissioning for the Starburst project, a wideband single-baseline radio interferometry backend dedicated to stellar observations. In addition, I led a survey of nearby active M dwarfs with the Karl G. Jansky Very Large Array (JVLA), detecting 12 bright (>10 mJy) radio bursts in 58 hours. This survey’s ultra-wide bandwidth (0.23-6.0 GHz) dynamic spectroscopy, unprecedented for stellar observations, revealed diverse behavior in the time-frequency plane. Flare star UV Ceti produced complex, luminous events reminiscent of brown dwarf aurorae; AD Leo sustained long-duration, intense, narrow-band "storms"; and YZ CMi emitted a burst with substructure with rapid frequency drift, resembling solar Type III bursts, which are attributed to electrons moving at speeds of order 10% of the speed of light.To search for the spatial signature of CMEs, I led 8.5-GHz observations with the Very Long Baseline Array simultaneous to 24 hours of the JVLA survey. This program detected non-thermal continuum emission from the stars in all epochs, as well as continuum flares on AD Leo and coherent bursts on UV Ceti, enabling measurement of the spatial offset between flaring and quiescent emission.These observations demonstrate the diversity of stellar transients that can be expected in time-domain radio surveys, especially with the advent of large low

  2. Studying Geoeffective Interplanetary Coronal Mass Ejections Between the Sun and Earth: Space Weather Implications of Solar Mass Ejection Imager Observations

    DTIC Science & Technology

    2009-05-14

    during the Mav 12th, 1997 ICME, /. Ahnos. Sol. Terr. Phys., 66, 1295-1309. Billings, D. E. (1966), A Guide to the Solar Corona , Academic, San Diego...SUBTITLE Studying geoeffective interplanetary coronal mass ejections Between the Sun and Earth: Space weather implications of Solar Mass Ejection...DISTRIBUTION . „ . ru^en.1 nomicmcni Approved for Public Release; Distribution Unlimited. *Boston College, Chestnut Hill, MA, **AFRL, National Solar Ob

  3. Statins in heart failure--With preserved and reduced ejection fraction. An update.

    PubMed

    Tousoulis, Dimitris; Oikonomou, Evangelos; Siasos, Gerasimos; Stefanadis, Christodoulos

    2014-01-01

    HMG-CoA reductase inhibitors or statins beyond their lipid lowering properties and mevalonate inhibition exert also their actions through a multiplicity of mechanisms. In heart failure (HF) the inhibition of isoprenoid intermediates and small GTPases, which control cellular function such as cell shape, secretion and proliferation, is of clinical significance. Statins share also the peroxisome proliferator-activated receptor pathway and inactivate extracellular-signal-regulated kinase phosphorylation suppressing inflammatory cascade. By down-regulating Rho/Rho kinase signaling pathways, statins increase the stability of eNOS mRNA and induce activation of eNOS through phosphatidylinositol 3-kinase/Akt/eNOS pathway restoring endothelial function. Statins change also myocardial action potential plateau by modulation of Kv1.5 and Kv4.3 channel activity and inhibit sympathetic nerve activity suppressing arrhythmogenesis. Less documented evidence proposes also that statins have anti-hypertrophic effects - through p21ras/mitogen activated protein kinase pathway - which modulate synthesis of matrix metalloproteinases and procollagen 1 expression affecting interstitial fibrosis and diastolic dysfunction. Clinical studies have partly confirmed the experimental findings and despite current guidelines new evidence supports the notion that statins can be beneficial in some cases of HF. In subjects with diastolic HF, moderately impaired systolic function, low b-type natriuretic peptide levels, exacerbated inflammatory response and mild interstitial fibrosis evidence supports that statins can favorably affect the outcome. Under the lights of this evidence in this review article we discuss the current knowledge on the mechanisms of statins' actions and we link current experimental and clinical data to further understand the possible impact of statins' treatment on HF syndrome.

  4. Ultrasound tissue characterization does not differentiate genotype, but indexes ejection fraction deterioration in becker muscular dystrophy.

    PubMed

    Giglio, Vincenzo; Puddu, Paolo Emilio; Holland, Mark R; Camastra, Giovanni; Ansalone, Gerardo; Ricci, Enzo; Mela, Julia; Sciarra, Federico; Di Gennaro, Marco

    2014-12-01

    The aims of the study were, first, to assess whether myocardial ultrasound tissue characterization (UTC) in Becker muscular dystrophy (BMD) can be used to differentiate between patients with deletions and those without deletions; and second, to determine whether UTC is helpful in diagnosing the evolution of left ventricular dysfunction, a precursor of dilated cardiomyopathy. Both cyclic variation of integrated backscatter and calibrated integrated backscatter (cIBS) were assessed in 87 patients with BMD and 70 controls. The average follow-up in BMD patients was 48 ± 12 mo. UTC analysis was repeated only in a subgroup of 40 BMD patients randomly selected from the larger overall group (15 with and 25 without left ventricular dysfunction). Discrimination between BMD patients with and without dystrophin gene deletion was not possible on the basis of UTC data: average cvIBS was 5.2 ± 1.2 and 5.5 ± 1.4 dB, and average cIBS was 29.9 ± 4.7 and 29.6 ± 5.8, respectively, significantly different (p < 0.001) only from controls (8.6 ± 0.5 and 24.6 ± 1.2 dB). In patients developing left ventricular dysfunction during follow-up, cIBS increased to 31.3 ± 5.4 dB, but not significantly (p = 0.08). The highest cIBS values (34.6 ± 5.3 dB, p < 0.09 vs. baseline, p < 0.01 vs BMD patients without left ventricular dysfunction) were seen in the presence of severe left ventricular dysfunction. Multivariate statistics indicated that an absolute change of 6 dB in cIBS is associated with a high probability of left ventricular dysfunction. UTC analysis does not differentiate BMD patients with or without dystrophin gene deletion, but may be useful in indexing left ventricular dysfunction during follow-up.

  5. Forward ejection fraction: a new index of left ventricular function in mitral regurgitation.

    PubMed

    Clancy, K F; Hakki, A H; Iskandrian, A S; Hadjimiltiades, S; Mundth, E D; Hakki, A H; Bemis, C E; Nestico, P F; DePace, N L; Segal, B L

    1985-09-01

    Previous studies have shown that a normal LVEF is not a reliable index of LV function in MR. We hypothesized that the forward EF, which is the forward stroke volume (measured by Fick or thermodilution) divided by end-diastolic volume (measured by contrast ventriculography) may be a useful index of LV function, since it represents LV emptying into the aorta. This index was examined in 54 patients with chronic MR who had normal EF (greater than or equal to 50%). There were significant correlations between the forward EF and the end-diastolic volume index (r = -0.69, p less than 0.001), end-systolic volume index (r = -0.64, p less than 0.001), cardiac index (r = 0.43, p less than 0.01), and the ratio of systolic pressure-to-end-systolic volume (r = 0.65, p less than 0.001). Patients were divided into two groups according to the forward EF: group I (n = 34) had forward EF less than or equal to 35%; and group II (n = 20) had forward EF greater than 35%. Of the 32 patients who subsequently underwent mitral valve replacement, 24 patients were in group I and eight patients were in group II. At a mean follow-up of 35 months, four patients died; all of them were in group I. Improvement in functional class occurred in 75% of surgical survivors (80% in group I and 63% in group II, p = NS). These preliminary data suggest that forward EF may be a useful index of LV performance in patients with MR who have normal EF.

  6. [Atrial filling fraction predicts left ventricular systolic function after myocardial infarction: pre-discharge echocardiographic evaluation].

    PubMed

    Galderisi, M; Fakher, A; Petrocelli, A; Alfieri, A; Garofalo, M; de Divitiis, O

    1995-10-01

    Aim of the study was to examine the relation between Doppler-derived indices of left ventricular diastolic and systolic function early after myocardial infarction. Fifty-three patients (31 males, 22 females) recovering from acute myocardial infarction underwent predischarge Doppler echocardiographic examination. Patients with age > 70 years, previous myocardial infarction, more than mild mitral and aortic regurgitation, mitral and aortic stenosis were excluded. Twenty-two healthy subjects (13 males; 9 females) free of coronary risk factors were selected as the control group. Both end-diastolic and end-systolic volumes and ejection fraction were measured by two-dimensional echocardiography. Pulsed Doppler was used to evaluate mitral inflow and left ventricular outflow velocity patterns. The following indices were measured: peak velocity of early (E) and late (A) flows, ratio of E/A peak velocities, ratio of early to late time velocity integrals, atrial filling fraction (time velocity integral A / time velocity integral of flow during total diastole) and deceleration time of E wave for mitral inflow; peak and time-velocity integral for left ventricular outflow. Stroke volume and cardiac output were obtained by pulsed Doppler using the left ventricular outflow method. The two groups were comparable for age, with blood pressure (p < 0.05) and heart rate (p < 0.01) reduced in myocardial infarction patients. Both end-diastolic and end-systolic volumes were significantly higher (both p < 0.0001) and ejection fraction (p < 0.0001) lower after myocardial infarction. Also stroke volume and cardiac output (both p < 0.0001) were reduced in myocardial infarction patients. No significant difference in Doppler indices of diastolic function was observed between the two groups, except for shortened deceleration time (p < 0.0001) in myocardial infarction patients. Multilinear regression analyses were performed separately into the two groups to identify determinants of left

  7. Characterizing the original ejection velocity field of the Koronis family

    NASA Astrophysics Data System (ADS)

    Carruba, V.; Nesvorný, D.; Aljbaae, S.

    2016-06-01

    An asteroid family forms as a result of a collision between an impactor and a parent body. The fragments with ejection speeds higher than the escape velocity from the parent body can escape its gravitational pull. The cloud of escaping debris can be identified by the proximity of orbits in proper element, or frequency, domains. Obtaining estimates of the original ejection speed can provide valuable constraints on the physical processes occurring during collision, and used to calibrate impact simulations. Unfortunately, proper elements of asteroids families are modified by gravitational and non-gravitational effects, such as resonant dynamics, encounters with massive bodies, and the Yarkovsky effect, such that information on the original ejection speeds is often lost, especially for older, more evolved families. It has been recently suggested that the distribution in proper inclination of the Koronis family may have not been significantly perturbed by local dynamics, and that information on the component of the ejection velocity that is perpendicular to the orbital plane (vW), may still be available, at least in part. In this work we estimate the magnitude of the original ejection velocity speeds of Koronis members using the observed distribution in proper eccentricity and inclination, and accounting for the spread caused by dynamical effects. Our results show that (i) the spread in the original ejection speeds is, to within a 15% error, inversely proportional to the fragment size, and (ii) the minimum ejection velocity is of the order of 50 m/s, with larger values possible depending on the orbital configuration at the break-up.

  8. Accretion-ejection models for AGN jets

    NASA Astrophysics Data System (ADS)

    Zanni, C.

    2008-10-01

    It is likely that jets from Active Galactic Nuclei derive their energy from accretion onto the central black hole. It is actually possible to fuel the jets by extracting energy and angular momentum from the accretion disk and/or the rotating black hole via the action of large-scale magnetic fields. In this talk I will first present results of analytical and numerical models of the launching process of jets from magnetized accretion disks: I will show that, although a sizeable fraction of the accretion power goes into the jets, these outflows are presumably only mildly relativistic. In the second place, I will therefore suggest that the strongly relativistic components observed at the VLBI scales are accelerated in the innermost parts of the AGNs by Blandford-Znajek and/or Compton-rocket processes. Nonetheless, the non-relativistic disk-wind is needed to collimate the relativistic component and to reproduce the total power of extragalactic jets.

  9. Inhibition of DNA ejection from bacteriophage by Mg+2 counterions

    NASA Astrophysics Data System (ADS)

    Lee, Sell; Tran, C. V.; Nguyen, T. T.

    2011-03-01

    The problem of inhibiting viral DNA ejection from bacteriophages by multivalent counterions, specifically Mg+2 counterions, is studied. Experimentally, it is known that MgSO4 salt has a strong and nonmonotonic effect on the amount of DNA ejected. There exists an optimal concentration at which the minimum amount of DNA is ejected from the virus. At lower or higher concentrations, more DNA is ejected from the capsid. We propose that this phenomenon is the result of DNA overcharging by Mg+2 multivalent counterions. As Mg+2 concentration increases from zero, the net charge of DNA changes from negative to positive. The optimal inhibition corresponds to the Mg+2 concentration where DNA is neutral. At lower/higher concentrations, DNA genome is charged. It prefers to be in solution to lower its electrostatic self-energy, which consequently leads to an increase in DNA ejection. By fitting our theory to available experimental data, the strength of DNA-DNA short range attraction energies, mediated by Mg+2, is found to be -0.004 kBT per nucleotide base. This and other fitted parameters agree well with known values from other experiments and computer simulations. The parameters are also in agreement qualitatively with values for tri- and tetravalent counterions.

  10. Analysis of melt ejection during long pulsed laser drilling

    NASA Astrophysics Data System (ADS)

    Ting-Zhong, Zhang; Zhi-Chao, Jia; Hai-Chao, Cui; De-Hua, Zhu; Xiao-Wu, Ni; Jian, Lu

    2016-05-01

    In pulsed laser drilling, melt ejection greatly influences the keyhole shape and its quality as well, but its mechanism has not been well understood. In this paper, numerical simulation and experimental investigations based on 304 stainless steel and aluminum targets are performed to study the effects of material parameters on melt ejection. The numerical method is employed to predict the temperatures, velocity fields in the solid, liquid, and vapour front, and melt pool dynamics of targets as well. The experimental methods include the shadow-graphic technique, weight method, and optical microscope imaging, which are applied to real-time observations of melt ejection phenomena, measurements of collected melt and changes of target mass, observations of surface morphology and the cross-section of the keyhole, respectively. Numerical and experimental results show that the metallic material with high thermal diffusivity like aluminum is prone to have a thick liquid zone and a large quantity of melt ejection. Additionally, to the best of our knowledge, the liquid zone is used to illustrate the relations between melt ejection and material thermal diffusivity for the first time. The research result in this paper is useful for manufacturing optimization and quality control in laser-material interaction. Project supported by the Natural Science Foundation of Jiangsu Province, China (Grant No. KYLX_0341) and the National Natural Science Foundation of China (Grant No. 61405147).

  11. Inhibition of DNA ejection from bacteriophage by Mg^+2 counterions

    NASA Astrophysics Data System (ADS)

    Lee, Seil; Tran, Cathy V.; Nguyen, Toan T.

    2009-03-01

    The problem of inhibiting viral DNA ejection from bacteriophages by multivalent counterions, especially Mg^+2 counterions, is studied. Experimentally, it is known that MgSO4 salt has a strong and non-monotonic effect on the amount of DNA ejected. There exists an optimal concentration at which the least DNA is ejected from the virus. At lower or higher concentrations, more DNA is ejected from the capsid. We propose that this phenomenon is the result of DNA overcharging by Mg^+2 multivalent counterions. As Mg^+2 concentration increases from zero, DNA net charge changes from negative to positive. The optimal inhibition corresponds to the Mg^+2 concentration where DNA is neutral. At lower/higher concentrations, DNA genome is charged. It prefers to be in solution to lower its electrostatic self-energy, which consequently leads to an increase in DNA ejection. Our theory fits experimental data well. The strength of DNA-DNA short range attraction, mediated by Mg^+2, is found to be -0.003 kBT per nucleotide base.

  12. Effect of Age, Estrogen Status, and Late-Life GPER Activation on Cardiac Structure and Function in the Fischer344×Brown Norway Female Rat.

    PubMed

    Alencar, Allan K; da Silva, Jaqueline S; Lin, Marina; Silva, Ananssa M; Sun, Xuming; Ferrario, Carlos M; Cheng, Cheping; Sudo, Roberto T; Zapata-Sudo, Gisele; Wang, Hao; Groban, Leanne

    2017-02-01

    Age-associated changes in cardiac structure and function, together with estrogen loss, contribute to the progression of heart failure with preserved ejection fraction in older women. To investigate the effects of aging and estrogen loss on the development of its precursor, asymptomatic left ventricular diastolic dysfunction, echocardiograms were performed in 10 middle-aged (20 months) and 30 old-aged (30 months) female Fischer344×Brown-Norway rats, 4 and 8 weeks after ovariectomy (OVX) and sham procedures (gonads left intact). The cardioprotective potential of administering chronic G1, the selective agonist to the new G-protein-coupled estrogen receptor (GPER), was further evaluated in old rats (Old-OVX+G1) versus age-matched, vehicle-treated OVX and gonadal intact rats. Advanced age and estrogen loss led to decreases in myocardial relaxation and elevations in filling pressure, in part, due to reductions in phosphorylated phospholamban and increases in cardiac collagen deposition. Eight weeks of G-protein-coupled estrogen receptor activation in Old-OVX+G1 rats reversed the adverse effects of age and estrogen loss on myocardial relaxation through increases in sarcoplasmic reticulum Ca(2+) ATPase expression and reductions in interstitial fibrosis. These findings may explain the preponderance of heart failure with preserved ejection fraction in older postmenopausal women and provide a promising, late-life therapeutic target to reverse or halt the progression of left ventricular diastolic dysfunction.

  13. Ejected Sedimentary Rocks of Mud Volcanoes as Indicators of Depositional Environments and of Hydrocarbon Generation within the South Caspian Basin, Azerbaijan

    NASA Astrophysics Data System (ADS)

    Berner, U.; Scheeder, G.; Kus, J.; Köthe, A.; Movsumova, U.

    2009-04-01

    Mud volcanoes are prominent geological features of the South Caspian Basin of Azerbaijan, one of the oldest oil producing regions worldwide. The basin is characterized by extreme sedimentation rates, which lead to the accumulation of large volumes of Mesozoic and Cenozoic sediments. These mostly unconsolidated strata reach thicknesses of up to 20 km and overlay a continental basement in the onshore part. Tectonic forces control the occurrences of mud volcanoes in regions with over-pressured subsurface sediments as mud volcanoes are closely linked to fault systems. The mud volcanoes of Azerbaijan are a surface expression of vertical hydrocarbon migration and offer the chance to investigate the subsurface by means of ejected rocks transported to the surface. These rocks of Mesozoic and Cenozoic sedimentary sequences are potential indicators of the regional hydrocarbon generation. The mud of nineteen volcano cones contained numerous ejected rock fragments, which we use to identify environmental and depositional parameters of the sediments of the Caspian Basin. We also intended to estimate the depth range from which the mud was transported to the surface using organic geochemical parameters. Mircopalaeontological investigations (calcareous nannoplankton) have been performed on selected samples. These analyses suggest that the investigated sediments are of Late Cretaceous to Palaeogene ages and relate to the stratigraphic interval during which the main hydrocarbon source rocks of Azerbaijan have been deposited. Organic geochemical, organic petrographical and mircopalaeontological investigations have been performed on selected samples of nineteen mud volcanoes. Analyses total organic carbon and total sulphur were performed on an elemental analyzer. These analyses suggest that the sediments can be classified as anoxic marine deposits whereas only few are sediments of a lacustrine environment. Bulk source rock information were obtained from RockEval pyrolysis. Resulting

  14. Polarization instability of Raman solitons ejected during supercontinuum generation.

    PubMed

    Chao, Qing; Wagner, Kelvin H

    2015-12-28

    We numerically investigate polarization instability of soliton fission and the polarization dynamics of Raman solitons ejected during supercontinuum generation in a photonics crystal fiber using the coupled vector generalized nonlinear Schrödinger equations for both linear and circular birefringent fibers. The evolution of the state of polarizations of the ejected Raman soliton as representated on the Poincaré sphere is affected by both nonlinear and linear polarization rotations on the Poincaré sphere. The polarization dynamics reveal the presence of a polarization separatrix and the emergence of stable slow and unstable fast eigen-polarizations for the Raman solitons ejected in the supercontinuum generation process. Circularly birefringent fiber is investigated and found to simplify the nonlinear polarization dynamics.

  15. Prompt solar proton events and coronal mass ejections

    NASA Technical Reports Server (NTRS)

    Kahler, S. W.; Hildner, E.; Van Hollebeke, M. A. I.

    1978-01-01

    Data from the HAO white-light coronagraph and the X-ray telescope on Skylab have been used to investigate the coronal manifestations of 18 prompt solar proton events observed on the IMP 7 spacecraft during the Skylab period. Evidence is found that a mass-ejection event is a necessary condition for the occurrence of a prompt proton event. Mass-ejection events can be observed directly in the white-light coronagraph when they occur near the limb and inferred from the presence of a long-decay X-ray event when they occur on the disk. It is suggested that: (1) the occurrence of mass-ejection events facilitates the escape of protons - whether accelerated at low or high altitudes - to the interplanetary medium; and (2) there may exist a proton acceleration region above or around the outward moving ejecta far above the flare site.

  16. Experimental investigation on ejecting low-temperature cooling superconducting magnets

    NASA Astrophysics Data System (ADS)

    Liu, Bin; Zhang, Qiang; Tong, Ming-wei; Hu, Peng; Wu, Shuang-ying; Cai, Qin; Qin, Zeng-hu

    2013-10-01

    With the development of the high-temperature superconducting (HTS) materials and refrigeration technologies, using ejecting refrigeration to cool the superconducting materials becomes the direction of HTS applications. In this paper, an experimental study has been carried out on the basis of the theory of analyzing the ejecting low-temperature cooling superconducting magnet. The relationship between area ratios and refrigeration performance at different system pressures was derived. In addition, the working fluid flow and suction chamber pressure of the ejector with different area ratios at various inlet pressures have been examined to obtain the performance of ejectors under different working conditions. The result shows that the temperature of liquid nitrogen can be reduced to 70 K by controlling the inlet water pressure when the pressurized water at 20 °C is used to eject the saturated liquid nitrogen, which can provide the stable operational conditions for the HTS magnets cooling.

  17. Capstan Friction Model for DNA Ejection from Bacteriophages

    NASA Astrophysics Data System (ADS)

    Ghosal, Sandip

    2012-12-01

    Bacteriophages infect cells by attaching to the outer membrane and injecting their DNA into the cell. The phage DNA is then transcribed by the cell’s transcription machinery. A number of physical mechanisms by which DNA can be translocated from the phage capsid into the cell have been identified. A fast ejection driven by the elastic and electrostatic potential energy of the compacted DNA within the viral capsid appears to be used by most phages, at least to initiate infection. In recent in vitro experiments, the speed of DNA translocation from a λ phage capsid has been measured as a function of ejected length over the entire duration of the event. Here, a mechanical model is proposed that is able to explain the observed dependence of exit velocity on ejected length, and that is also consistent with the accepted picture of the geometric arrangement of DNA within the viral capsid.

  18. Ejection of a rear facing, golf cart passenger.

    PubMed

    Schau, Kyle; Masory, Oren

    2013-10-01

    The following report details the findings of a series of experiments and simulations performed on a commercially available, shuttle style golf cart during several maneuvers involving rapid accelerations of the vehicle. It is determined that the current set of passive restraints on these types of golf carts are not adequate in preventing ejection of a rear facing passenger during rapid accelerations in the forward and lateral directions. Experimental data and simulations show that a hip restraint must be a minimum of 13 in. above the seat in order to secure a rear facing passenger during sharp turns, compared to the current restraint height of 5 in. Furthermore, it is determined that a restraint directly in front of the rear facing passenger is necessary to prevent ejection. In addressing these issues, golf cart manufacturers could greatly reduce the likelihood of injury due to ejection of a rear facing, golf cart passenger.

  19. Three-dimensional reconstruction of coronal mass ejections

    NASA Technical Reports Server (NTRS)

    Jackson, Bernard V.; Hick, Paul

    1994-01-01

    Computer assisted tomography (CAT) techniques are used to reconstruct the three dimensional shape of coronal mass ejections in the interplanetary medium. Both the Helios 2 spacecraft zodiacal-light photometers and the Solwind coronograph measure changes in Thomson scattering of sunlight from electrons. The technique from near-perpendicular Solwind and Helios views are applied to determine the density of a mass ejection which left the solar surface on 24 May 1979. The coronograph and the Helios perspective views are not simultaneous; the Solwind observations extend outward to sky plane distances of only 10 of the solar radius, whereas the Helios 16 photometer observes to as close as 17 of the solar radius from the sun. The solution is obtained by assuming outward radial expansion and that the coronal mass ejections (CME's) have the same speed everywhere at the same height. The analyses show that CME's are extensive three dimensional structures (the CME of 24 May appears approximately shell) like in three dimensions.

  20. Recent STEREO Observations of Coronal Mass Ejections

    NASA Technical Reports Server (NTRS)

    SaintCyr, Chris Orville; Xie, Hong; Mays, Mona Leila; Davila, Joseph M.; Gilbert, Holly R.; Jones, Shaela I.; Pesnell, William Dean; Gopalswamy, Nat; Gurman, Joseph B.; Yashiro, Seiji; Wuelser, Jean-Pierre; Howard, Russell A.; Thompson, Barbara J.; Thompson, William T.

    2008-01-01

    Over 400 CMEs have been observed by STEREO SECCHI COR1 during the mission's three year duration (2006-2009). Many of the solar activity indicators have been at minimal values over this period, and the Carrington rotation-averaged CME rate has been comparable to that measured during the minima between Cycle 21-22 (SMM C/P) and Cycle 22-23 (SOHO LASCO). That rate is about 0.5 CMEs/day. During the current solar minimum (leading to Cycle 24), there have been entire Carrington rotations where no sunspots were detected and the daily values of the 2800 MHz solar flux remained below 70 sfu. CMEs continued to be detected during these exceptionally quiet periods, indicating that active regions are not necessary to the generation of at least a portion of the CME population. In the past, researchers were limited to a single view of the Sun and could conclude that activity on the unseen portion of the disk might be associated with CMEs. But as the STEREO mission has progressed we have been able to observe an increasing fraction of the Sun's corona with STEREO SECCHI EUVI and were able to eliminate this possibility. Here we report on the nature of CMEs detected during these exceptionally quiet periods, and we speculate on how the corona remains dynamic during such conditions.

  1. Nusat I - The first gas can ejected satellite

    NASA Astrophysics Data System (ADS)

    Twiggs, Robert J.

    Nusat I, an 18-inch diameter satellite, made history on April 29, 1985 by being the first satellite ejected from a newly designed Get-Away-Special canister on the Challenger orbiter. This ejection marked the beginning of a new era of satellite designs which can be inexpensively placed in orbit via the Space Shuttle. This paper describes the development of that project, including the project organization and funding, satellite design evolution, final design objectives, final satellite assembly and testing, integration before launch, and operational performance.

  2. Relevance of the triglyceride-to-high-density lipoprotein cholesterol ratio as an important lipid fraction in apparently healthy, young, and middle-aged Indian men

    PubMed Central

    Kohli, Aparna; Siddhu, Anupa; Pandey, Ravindra M.; Reddy, K. Srinath

    2017-01-01

    Context: Cardiovascular disease (CVD) is the largest cause of mortality in Indians. Insulin resistance and related dyslipidemia of increased triglyceride (TG), small dense low-density lipoprotein (sd-LDL) particles, and decreased high-density lipoprotein-cholesterol (HDL-C) are associated with increased risk of CVD. TG/HDL-C ratio could be a potential surrogate marker for this South Asian phenotype. Data are scarce on the relevance of TG/HDL-C ratio as a useful lipid marker among Indians. Aims: To study the prevalence of TG/HDL-C ratio among healthy, young, and middle-aged Indian men (25–44 years) and its relationship with other lipid and nonlipid factors. Subjects and Methods: In this cross-sectional analysis, fasting blood samples from 236 healthy participants recruited from an urban community setting were tested for TG/HDL-C ratio, HDL-C, TG, total cholesterol (TC), non-HDL-C, TC/HDL-C, high-sensitivity C-reactive protein, body mass index (BMI), and body fat. Results: Mean (standard deviation) age of participants was 34.7 (7.7) years; median (interquartile range) TG/HDL-C ratio was 4 (2.85-5.2). More than half (51.3%) the participants (n = 121) recorded abnormal TG/HDL-C ratio (≥4.0). Across tertiles of TG/HDL-C ratio, there was a significant trend of higher conventional lipid parameters such as non-HDL-C*, TC/HDL-C ratio*, TG*, HDL-C*, TC**; and non-lipid parameters body-fat* and BMI*** (*P < 0.001, **P = 0.015, ***P = 0.002). LDL-C showed moderate and nonsignificant (P = 0.646) increase across tertiles. Conclusion: In a sample of apparently healthy, young, and middle-aged Indian men abnormal TG/HDL-C ratio levels were observed among more than half the participants. The TG/HDL-C ratio was closely associated with other lipid parameters and measures of adiposity, such as BMI and body fat, apart from its previously documented unique association with sd-LDL particles. TG/HDL-C ratio should be evaluated in future for risk prediction of incident CVD among Indians

  3. IMPULSIVE ACCELERATION OF CORONAL MASS EJECTIONS. I. STATISTICS AND CORONAL MASS EJECTION SOURCE REGION CHARACTERISTICS

    SciTech Connect

    Bein, B. M.; Berkebile-Stoiser, S.; Veronig, A. M.; Temmer, M.; Muhr, N.; Kienreich, I.; Utz, D.

    2011-09-10

    We use high time cadence images acquired by the STEREO EUVI and COR instruments to study the evolution of coronal mass ejections (CMEs) from their initiation through impulsive acceleration to the propagation phase. For a set of 95 CMEs we derived detailed height, velocity, and acceleration profiles and statistically analyzed characteristic CME parameters: peak acceleration, peak velocity, acceleration duration, initiation height, height at peak velocity, height at peak acceleration, and size of the CME source region. The CME peak accelerations we derived range from 20 to 6800 m s{sup -2} and are inversely correlated with the acceleration duration and the height at peak acceleration. Seventy-four percent of the events reach their peak acceleration at heights below 0.5 R{sub sun}. CMEs that originate from compact sources low in the corona are more impulsive and reach higher peak accelerations at smaller heights. These findings can be explained by the Lorentz force, which drives the CME accelerations and decreases with height and CME size.

  4. Late Na+ current and protracted electrical recovery are critical determinants of the aging myopathy

    PubMed Central

    Signore, Sergio; Sorrentino, Andrea; Borghetti, Giulia; Cannata, Antonio; Meo, Marianna; Zhou, Yu; Kannappan, Ramaswamy; Pasqualini, Francesco; O'Malley, Heather; Sundman, Mark; Tsigkas, Nikolaos; Zhang, Eric; Arranto, Christian; Mangiaracina, Chiara; Isobe, Kazuya; Sena, Brena F.; Kim, Junghyun; Goichberg, Polina; Nahrendorf, Matthias; Isom, Lori L.; Leri, Annarosa; Anversa, Piero; Rota, Marcello

    2015-01-01

    The aging myopathy manifests itself with diastolic dysfunction and preserved ejection fraction. We raised the possibility that, in a mouse model of physiological aging, defects in electromechanical properties of cardiomyocytes are important determinants of the diastolic characteristics of the myocardium, independently from changes in structural composition of the muscle and collagen framework. Here we show that an increase in the late Na+ current (INaL) in aging cardiomyocytes prolongs the action potential (AP) and influences temporal kinetics of Ca2+ cycling and contractility. These alterations increase force development and passive tension. Inhibition of INaL shortens the AP and corrects dynamics of Ca2+ transient, cell contraction and relaxation. Similarly, repolarization and diastolic tension of the senescent myocardium are partly restored. Thus, INaL offers inotropic support, but negatively interferes with cellular and ventricular compliance, providing a new perspective of the biology of myocardial aging and the aetiology of the defective cardiac performance in the elderly. PMID:26541940

  5. 78 FR 55137 - Federal Motor Vehicle Safety Standards; Ejection Mitigation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-09

    ... Vehicle Safety Systems (TRW), and the Automotive Occupant Restraints Council (AORC)/Automotive Safety... September 9, 2013 Part II Department of Transportation National Highway Traffic Safety Administration 49 CFR Part 571 Federal Motor Vehicle Safety Standards; Ejection Mitigation; Final Rule #0;#0;Federal...

  6. Discovery of collimated ejection from the symbiotic binary BF Cygni

    NASA Astrophysics Data System (ADS)

    Skopal, A.; Tomov, N. A.; Tomova, M. T.

    2013-03-01

    Context. Detection of collimated ejection from white dwarfs (WD) in symbiotic binaries is very rare and has employed a variety of methods in X-ray, radio, optical imagery, and spectroscopy. To date, its signature in the optical spectra has only been recorded for four objects (MWC 560, Hen 3-1341, StHα 190, and Z And). Aims: We present the first observational evidence of highly-collimated bipolar ejection from the symbiotic binary BF Cyg, which developed during its current (2006-12) active phase, and determine their physical parameters. Methods: We monitored the outburst with the optical high-resolution spectroscopy and multicolour UBVRCIC photometry. Results: During 2009, three years after the 2006-eruption of BF Cyg, satellite components to Hα and Hβ lines emerged in the spectrum. During 2012, they became stable and were located symmetrically with respect to the main emission core of the line. Spectral properties of these components suggest bipolar ejection collimated within an opening angle of ≲15°, whose radiation is produced by an optically thin medium with the emission measure of 1-2 × 1059 (d/3.8 kpc)2 cm-3. Conclusions: Formation of the collimated ejection a few years after the eruption and its evolution on a time scale of years at a constant optical brightness can aid us in better understanding the accretion process during the active phases of symbiotic stars. Based on data collected with 2-m telescope at the Rozhen National Astronomical Observatory and the David Dunlap Observatory.

  7. Experimental Investigation of the Dispersion of Liquids by Ejection Atomizers

    NASA Astrophysics Data System (ADS)

    Arkhipov, V. A.; Bondarchuk, S. S.; Evsevleev, M. Ya.; Zharova, I. K.; Zhukov, A. S.; Zmanovskii, S. V.; Kozlov, E. A.; Konovalenko, A. I.; Trofimov, V. F.

    2013-11-01

    This paper presents the results of an experimental investigation of the dispersivity of liquid droplets in the spray cone of ejection atomizers. The calculational droplet size distribution function was measured by the method of low angles of the probe laser radiation scattering indicatrix on a pneumohydraulic bench under cold blow conditions. The efficiency of the proposed circuit designs of atomizers has been analyzed.

  8. Mass ejection from black hole-neutron star binaries

    NASA Astrophysics Data System (ADS)

    Kyutoku, Koutarou; Ioka, Kunihito; Shibata, Masaru

    2014-03-01

    Black hole-neutron star binaries are ones of the most promising sources of gravitational waves for upcoming second-generation detectors. To confirm gravitational-wave detection and obtain as much information as possible, it is desirable to observe electromagnetic counterparts simultaneously. It has been pointed out by many authors that various electromagnetic signals are reasonably expected if substantial material is ejected during the binary merger. One plausible mechanism of mass ejection from black hole-neutron star binaries is tidal disruption of neutron stars by the tidal force exerted by black holes. A quantitative study of this dynamical mass ejection requires numerical-relativity simulations. We perform simulations of black hole-neutron star binaries focusing on the dynamical mass ejection for a range of binary parameters including equations of state of neutron star matter. We present important results such as masses and velocities of ejecta obtained by our simulations, and also discuss possible characteristics of electromagnetic counterparts to black hole-neutron star binaries. In particular, we focus on anisotropy and bulk velocity (i.e., the velocity component other than the expansion velocity) of the ejecta, and electromagnetic features resulting from them.

  9. T-wave alternans negative coronary patients with low ejection and benefit from defibrillator implantation

    NASA Technical Reports Server (NTRS)

    Hohnloser, S. H.; Ikeda, T.; Bloomfield, D. M.; Dabbous, O. H.; Cohen, R. J.

    2003-01-01

    In a trial of prophylactic implantation of a defibrillator, a mortality benefit was seen among patients with previous myocardial infarction and a left-ventricular ejection fraction of 0.30 or less. We identified 129 similar patients from two previously published clinical trials in which microvolt T-wave alternans testing was prospectively assessed. At 24 months of follow-up, no sudden cardiac death or cardiac arrest was seen among patients who tested T-wave alternans negative, compared with an event rate of 15.6% among the remaining patients. Testing of T-wave alternans seems to identify patients who are at low risk of ventricular tachyarrhythmic event and who may not benefit from defibrillator therapy.

  10. Age-related changes in intraventricular kinetic energy: a physiological or pathological adaptation?

    PubMed Central

    Wong, James; Chabiniok, Radomir; deVecchi, Adelaide; Dedieu, Nathalie; Sammut, Eva; Schaeffter, Tobias

    2016-01-01

    Aging has important deleterious effects on the cardiovascular system. We sought to compare intraventricular kinetic energy (KE) in healthy subjects of varying ages with subjects with ventricular dysfunction to understand if changes in energetic momentum may predispose individuals to heart failure. Four-dimensional flow MRI was acquired in 35 healthy subjects (age: 1–67 yr) and 10 patients with left ventricular (LV) dysfunction (age: 28–79 yr). Healthy subjects were divided into age quartiles (1st quartile: <16 yr, 2nd quartile: 17–32 yr, 3rd quartile: 33–48 yr, and 4th quartile: 49–64 yr). KE was measured in the LV throughout the cardiac cycle and indexed to ventricular volume. In healthy subjects, two large peaks corresponding to systole and early diastole occurred during the cardiac cycle. A third smaller peak was seen during late diastole in eight adults. Systolic KE (P = 0.182) and ejection fraction (P = 0.921) were preserved through all age groups. Older adults showed a lower early peak diastolic KE compared with children (P < 0.0001) and young adults (P = 0.025). Subjects with LV dysfunction had reduced ejection fraction (P < 0.001) and compared with older healthy adults exhibited a similar early peak diastolic KE (P = 0.142) but with the addition of an elevated KE in diastasis (P = 0.029). In healthy individuals, peak diastolic KE progressively decreases with age, whereas systolic peaks remain constant. Peak diastolic KE in the oldest subjects is comparable to those with LV dysfunction. Unique age-related changes in ventricular diastolic energetics might be physiological or herald subclinical pathology. PMID:26747496

  11. Ejection-ionization of molecules from free standing graphene

    NASA Astrophysics Data System (ADS)

    Verkhoturov, Stanislav V.; Czerwinski, Bartlomiej; Verkhoturov, Dmitriy S.; Geng, Sheng; Delcorte, Arnaud; Schweikert, Emile A.

    2017-02-01

    We present the first data on emission of -C60 stimulated by single impacts of 50 keV C60+2 on the self-assembled molecular layer of C60 deposited on free standing 2 layer graphene. The yield, Y, of -C60 emitted in the transmission direction is 1.7%. To characterize the ejection and ionization of molecules, we have measured the emission of -C60 from the surface of bulk C60 (Y = 3.7%) and from a single layer of C60 deposited on bulk pyrolytic graphite (Y = 3.3%). To gain insight into the mechanism(s) of ejection, molecular dynamic simulations were performed. The scenario of the energy deposition and ejection of molecules is different for the case of graphene due to the confined volume of projectile-analyte interaction. In the case of 50 keV C60+2 impacts on graphene plus C60, the C atoms of the projectile collide with those of the target. The knocked-on atoms take on a part of the kinetic energy of the projectile atoms. Another part of the kinetic energy is deposited into the rim around the impact site. The ejection of molecules from the rim is a result of collective movement of the molecules and graphene membrane, where the membrane movement provides the impulse for ejection. The efficient emission of the intact molecular ions implies an effective ionization probability of intact C60. The proposed mechanism of ionization involves the tunneling of electrons from the vibrationally exited area around the hole to the ejecta.

  12. The population of low-mass X-ray binaries ejected from black-hole retaining globular clusters

    NASA Astrophysics Data System (ADS)

    Giesler, Matthew; Clausen, Drew; Ott, Christian

    2017-01-01

    The fate of stellar-mass black holes (BHs) formed in globular clusters (GCs) is still widely uncertain; recent studies suggest that GCs may retain a substantial population of BHs, in contrast to the long held belief of a few to zero BHs. We model the population of BH low-mass X-ray binaries (BH-LMXB) ejected from GCs that are representative of Milky Way GCs with variable BH populations. We simulate the formation of BH-binaries in GCs through exchange interactions between binary and single stars in the company of tens to hundreds of BHs. We construct Monte Carlo realizations of the present day BH-LMXB population that account for both the binary evolution of the ejected systems and the dynamical evolution of these binaries in the Milky Way potential. We find that the orbital parameters of the ejected binaries are sensitive to both the GC's observable structural parameters and its unobservable BH population. Our results suggest that these dynamically formed BH-LMXBs will be easily distinguishable, by their distinctive kinematic properties and larger BH masses, from those produced in the field. Identifying this population of BH-LMXBs, an ideal observable proxy for elusive single BHs, would provide observational constraints on the GC BH retention fraction.

  13. Subdwarf B stars from the common envelope ejection channel

    NASA Astrophysics Data System (ADS)

    Xiong, H.; Chen, X.; Podsiadlowski, Ph.; Li, Y.; Han, Z.

    2017-02-01

    Context. Subdwarf B stars (sdB) are important to stellar evolutionary theory and asteroseismology, and they are crucial to our understanding of the structure and evolution of the Galaxy. According to the canonical binary scenario, the majority of sdBs are produced from low-mass stars with degenerate cores where helium is ignited in a way of flashes. Owing to numerical difficulties, the models of produced sdBs are generally constructed from more massive stars with non-degenerate cores. This leaves several uncertainties on the exact characteristics of sdB stars. Aims: The purpose of this paper is to study the characteristics of sdBs produced from the common envelope (CE) ejection channel. Methods: We used the stellar evolution code Modules for Experiments in Stellar Astrophysics (MESA), which can resolve flashes during stellar evolution. To mimic the CE ejection process, we first evolved a single star to a position near the tip of the red giant branch, then artificially removed its envelope with a very high mass-loss rate until the envelope began to shrink. Finally, we followed the evolution of the remnant until it became a helium or a carbon-oxygen white dwarf. Results: The sdB stars produced from the CE ejection channel appear to form two distinct groups on the effective temperature-gravity diagram. One group, referred to as the flash-mixing sdBs, almost has no H-rich envelope and crowds at the hottest temperature end of the extreme horizontal branch (EHB), while the other group, called the canonical sdBs, has significant H-rich envelope and is spread throughout the entire canonical EHB region. The key factor for the dichotomy of the sdB properties is the development of convection during the first helium flash, that is, that the convection region penetrates the H-rich envelope in the case of the flash-mixing sdBs, but fails to do this in the case of the canonical sdBs. Conclusions: The dichotomy of the sdB properties from the CE ejection channel is intrinsic and

  14. Simulating AIA observations of a flux rope ejection

    NASA Astrophysics Data System (ADS)

    Pagano, P.; Mackay, D. H.; Poedts, S.

    2014-08-01

    Context. Coronal mass ejections (CMEs) are the most violent phenomena observed on the Sun. Currently, extreme ultraviolet (EUV) images from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO) are providing new insights into the early phase of CME evolution. In particular, observations now show the ejection of magnetic flux ropes from the solar corona and how they evolve into CMEs. While this is the case, these observations are difficult to interpret in terms of basic physical mechanisms and quantities. To fully understand CMEs we need to compare equivalent quantities derived from both observations and theoretical models. This will aid in bridging the gap between observations and models. Aims: To this end, we aim to produce synthesised AIA observations from simulations of a flux rope ejection. To carry this out we include the role of thermal conduction and radiative losses, both of which are important for determining the temperature distribution of the solar corona during a CME. Methods: We perform a simulation where a flux rope is ejected from the solar corona. From the density and temperature of the plasma in the simulation we synthesise AIA observations. The emission is then integrated along the line of sight using the instrumental response function of AIA. Results: We sythesise observations of AIA in the channels at 304 Å, 171 Å, 335 Å, and 94 Å. The synthesised observations show a number of features similar to actual observations and in particular reproduce the general development of CMEs in the low corona as observed by AIA. In particular we reproduce an erupting and expanding arcade in the 304 Å and 171 Å channels with a high density core. Conclusions: The ejection of a flux rope reproduces many of the features found in the AIA observations. This work is therefore a step forward in bridging the gap between observations and models, and can lead to more direct interpretations of EUV observations in terms of flux rope

  15. Ejection of the Massive Hydrogen-rich Envelope Timed with the Collapse of the Stripped SN 2014C

    NASA Astrophysics Data System (ADS)

    Margutti, Raffaella; Kamble, A.; Milisavljevic, D.; Zapartas, E.; de Mink, S. E.; Drout, M.; Chornock, R.; Risaliti, G.; Zauderer, B. A.; Bietenholz, M.; Cantiello, M.; Chakraborti, S.; Chomiuk, L.; Fong, W.; Grefenstette, B.; Guidorzi, C.; Kirshner, R.; Parrent, J. T.; Patnaude, D.; Soderberg, A. M.; Gehrels, N. C.; Harrison, F.

    2017-02-01

    We present multi-wavelength observations of SN 2014C during the first 500 days. These observations represent the first solid detection of a young extragalactic stripped-envelope SN out to high-energy X-rays ∼40 keV. SN 2014C shows ordinary explosion parameters (Ek ∼ 1.8 × 1051 erg and Mej ∼ 1.7 M⊙). However, over an ∼1 year timescale, SN 2014C evolved from an ordinary hydrogen-poor supernova into a strongly interacting, hydrogen-rich supernova, violating the traditional classification scheme of type-I versus type-II SNe. Signatures of the SN shock interaction with a dense medium are observed across the spectrum, from radio to hard X-rays, and revealed the presence of a massive shell of ∼1 M⊙ of hydrogen-rich material at ∼6 × 1016 cm. The shell was ejected by the progenitor star in the decades to centuries before collapse. This result challenges current theories of massive star evolution, as it requires a physical mechanism responsible for the ejection of the deepest hydrogen layer of H-poor SN progenitors synchronized with the onset of stellar collapse. Theoretical investigations point at binary interactions and/or instabilities during the last nuclear burning stages as potential triggers of the highly time-dependent mass loss. We constrain these scenarios utilizing the sample of 183 SNe Ib/c with public radio observations. Our analysis identifies SN 2014C-like signatures in ∼10% of SNe. This fraction is reasonably consistent with the expectation from the theory of recent envelope ejection due to binary evolution if the ejected material can survive in the close environment for 103–104 years. Alternatively, nuclear burning instabilities extending to core C-burning might play a critical role.

  16. The Accretion Flow-Discrete Ejection Connection in GRS 1915+105

    NASA Astrophysics Data System (ADS)

    Punsly, Brian; Rodriguez, Jérôme; Trushkin, Sergei A.

    2016-07-01

    The microquasar GRS 1915+105 is known for its spectacular discrete ejections. They occur unexpectedly, thus their inception has escaped direct observation. It has been shown that the X-ray flux increases in the hours leading up to a major ejection. In this article, we consider the serendipitous interferometric monitoring of a modest version of a discrete ejection described in Reid et al. that would have otherwise escaped detection in daily radio light curves. The observation begins ˜1 hr after the onset of the ejection, providing unprecedented accuracy on the estimate of the ejection time. The astrometric measurements allow us to determine the time of ejection as {{MJD}} {56436.274}-0.013+0.016, i.e., within a precision of 41 minutes (95% confidence). Just like larger flares, we find that the X-ray luminosity increases in last 2-4 hr preceding ejection. Our finite temporal resolution indicates that this elevated X-ray flux persists within {21.8}-19.1+22.6 minutes of the ejection with 95% confidence, the highest temporal precision of the X-ray-superluminal ejection connection to date. This observation provides direct evidence that the physics that launches major flares occurs on smaller scales as well (lower radio flux and shorter ejection episodes). The observation of a X-ray spike prior to a discrete ejection, although of very modest amplitude, suggests that the process linking accretion behavior to ejection is general from the smallest scales to high luminosity major superluminal flares.

  17. Velocity-dependent isotope fractionation in secondary-ion emission

    SciTech Connect

    Gnaser, H.; Hutcheon, I.D.

    1987-01-15

    The formation of secondary ions is subject to isotopic fractionation (differing ionization probabilities for two isotopes) that depends linearly on the inverse velocity of the ejected ions. Theoretically, such a correlation follows directly from an exponential dependence of the ionization probability P on v/sup -1/, Pproportionalexp(-v/sub 0//v). The parameter v/sub 0/, derived from the experiment, amounts to --2 x 10/sup 6/ cm/sec for B, Si, and Ca ions.

  18. Neutrino diffusion and mass ejection in protoneutron stars

    SciTech Connect

    Almeida, L. G.; Rodrigues, H.; Portes, D. Jr.; Duarte, S. B.

    2010-11-15

    We discuss the mass ejection mechanism induced by diffusion of neutrino during the early stage of the protoneutron star cooling. A dynamical calculation is employed in order to determine the amount of matter ejected and the remnant compact object mass. An equation of state considering hadronic and quark phases for the stellar dense matter was used to solve the whole time evolution of the system during the cooling phase. The initial neutrino population was obtained by considering beta equilibrium in the dense stellar matter with confined neutrinos, in the very early period of the deleptonic stage of the nascent pulsar. For specified initial configurations of the protoneutron star, we solve numerically the set of equations of motion together with neutrino diffusion through the dense stellar medium.

  19. Dynamics of bacteriophage genome ejection in vitro and in vivo

    NASA Astrophysics Data System (ADS)

    Panja, Debabrata; Molineux, Ian J.

    2010-12-01

    Bacteriophages, phages for short, are viruses of bacteria. The majority of phages contain a double-stranded DNA genome packaged in a capsid at a density of ~500 mg ml-1. This high density requires substantial compression of the normal B-form helix, leading to the conjecture that DNA in mature phage virions is under significant pressure, and that pressure is used to eject the DNA during infection. A large number of theoretical, computer simulation and in vitro experimental studies surrounding this conjecture have revealed many—though often isolated and/or contradictory—aspects of packaged DNA. This prompts us to present a unified view of the statistical physics and thermodynamics of DNA packaged in phage capsids. We argue that the DNA in a mature phage is in a (meta)stable state, wherein electrostatic self-repulsion is balanced by curvature stress due to confinement in the capsid. We show that in addition to the osmotic pressure associated with the packaged DNA and its counterions, there are four different pressures within the capsid: pressure on the DNA, hydrostatic pressure, the pressure experienced by the capsid and the pressure associated with the chemical potential of DNA ejection. Significantly, we analyze the mechanism of force transmission in the packaged DNA and demonstrate that the pressure on DNA is not important for ejection. We derive equations showing a strong hydrostatic pressure difference across the capsid shell. We propose that when a phage is triggered to eject by interaction with its receptor in vitro, the (thermodynamic) incentive of water molecules to enter the phage capsid flushes the DNA out of the capsid. In vivo, the difference between the osmotic pressures in the bacterial cell cytoplasm and the culture medium similarly results in a water flow that drags the DNA out of the capsid and into the bacterial cell.

  20. Associations between coronal mass ejections and interplanetary shocks

    NASA Technical Reports Server (NTRS)

    Sheeley, N. R., Jr.; Howard, R. A.; Koomen, M. J.; Michels, D. J.; Schwenn, R.; Muhlhauser, K. H.; Rosenbauer, H.

    1983-01-01

    Nearly continuous complementary coronal observations and interplanetary plasma measurements for the years 1979-1982 are compared. It is shown that almost all low latitude high speed coronal mass ejections (CME's) were associated with shocks at HELIOS 1. Some suitably directed low speed CME's were clearly associated with shocks while others may have been associated with disturbed plasma (such as NCDE's) without shocks. A few opposite hemisphere CME's associated with great flares seem to be associated with shocks at HELIOS.

  1. Characterization of Boulders Ejected from Small Impact Craters

    NASA Astrophysics Data System (ADS)

    Bart, G. D.; Melosh, H. J.; Strom, R. G.

    2004-11-01

    When an asteroid or comet impacts the surface of a solid body, some of the surface material is often ejected from the crater in the form of blocks. We are characterizing the size and location of such blocks around craters on the Moon and Mars. The lunar craters were observed in Lunar Orbiter III images from P-12 and S-18. The Mars crater was observed in Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) Release No. MOC2-712. The craters range in size from 300 m to 3 km diameter. We measured the diameters of boulders observed around the craters, and also measured the distance between the boulder and the crater center. We then calculate the ejection velocity of each boulder based on how far the block was from the crater. The data indicate that larger boulders are more frequently found close to the crater rim rather than far away. The size of the ejecta drops off as a power law with distance from the crater. Our results are consistent with studies by Vickery (1986, 1987), which indirectly found the distribution of ejecta sizes from large craters by analyzing the size and distribution of their secondary craters. Our work characterizes the other end of the ejecta spectrum --- low velocity boulders ejected from small craters. We have also constructed R-plots of the boulder diameters for each crater. We found that the R-plot for the boulders has a dependence remarkably similar to an R-plot of the diameters of secondary craters. This similarity supports the already accepted idea that the impactors that produce secondaries are blocks ejected from larger craters. It is also consistent with the interpretation that the upturn of the cratering curve at small diameters on the terrestrial planets is due to secondary impacts rather than a primary population as some have proposed.

  2. Determining the full halo coronal mass ejection characteristics

    NASA Astrophysics Data System (ADS)

    Fainshtein, V. G.

    2009-03-01

    In this paper we determined the parameters of 45 full halo coronal mass ejections (HCMEs) for various modifications of their cone forms (“ice cream cone models”). We show that the CME determined characteristics depend significantly on the CME chosen form. We show that, regardless of the CME chosen form, the trajectory of practically all the considered HCMEs deviate from the radial direction to the Sun-to-Earth axis at the initial stage of their movement.

  3. Multinucleon Ejection Model for Two Body Current Neutrino Interactions

    SciTech Connect

    Sobczyk, Jan T.; /Fermilab

    2012-06-01

    A model is proposed to describe nucleons ejected from a nucleus as a result of two-body-current neutrino interactions. The model can be easily implemented in Monte Carlo neutrino event generators. Various possibilities to measure the two-body-current contribution are discussed. The model can help identify genuine charge current quasielastic events and allow for a better determination of the systematic error on neutrino energy reconstruction in neutrino oscillation experiments.

  4. The impact ejection of living organisms into space

    NASA Technical Reports Server (NTRS)

    Melosh, H. J.

    1985-01-01

    The possibility of natural processes to blast living organisms into space was examined. It is suggested that rocks ejected from the Earth by a giant meteorite or comet impact can carry microorganisms into space. Such microscopic Earth life would have an opportunity to colonize the other planets if it can survive the rigors of space until it falls into the atmosphere of a hospitable planet.

  5. Evolving Magnetic Structures and Their Relation to Coronal Mass Ejections

    NASA Technical Reports Server (NTRS)

    Feynman, J.

    1996-01-01

    Solar activity regions are frequently concentrated into cluster which persist for many solar rotations. These activity complexes are associated with weak dispersed magnetic fields which are most apparent after the activity itself has ceased. We call this combination of persistent activity and dispersed Evolving Magnetic Structures (EMS). Here we show examples of EMSs and describe the evolution of an EMS associated with major Coronal Mass Ejections (CME) and other solar and magnetic disturbances.

  6. Dynamic Supersonic Base Store Ejection Simulation Using Beggar

    DTIC Science & Technology

    2008-12-01

    models employ nonlinear and complex second order relationships to determine the Reynolds Stresses • first-order closure models express the Reynolds...during an aft store ejection. Beggar allows the use of the algebraic Baldwin-Lomax (B-L) turbu- lence model , the Spalart-Allmaras ( S -A) one-equation... model , and Detached-Eddy Simulation (DES) (where S -A is implemented as the RANS model ). In his work, Simko [29] found that the S -A turbulence model on

  7. Ejection behavior characteristics in experimental cratering in sandstone targets

    NASA Astrophysics Data System (ADS)

    Sommer, Frank; Reiser, Fiona; Dufresne, Anja; Poelchau, Michael H.; Hoerth, Tobias; Deutsch, Alex; Kenkmann, Thomas; Thoma, Klaus

    2013-01-01

    Within the frame of the MEMIN research unit (Multidisciplinary Experimental and Numerical Impact Research Network), impact experiments on sandstone targets were carried out to systematically study the influence of projectile mass, velocity, and target water saturation on the cratering and ejection processes. The projectiles were accelerated with two-stage light-gas guns (Ernst-Mach-Institute) onto fine-grained targets (Seeberger sandstone) with about 23% porosity. Collection of the ejecta on custom-designed catchers allowed determination of particle shape, size distribution, ejection angle, and microstructures. Mapping of the ejecta imprints on the catcher surface enabled linking of the different patterns to ejection stages observed on high-speed videos. The increase in projectile mass from 0.067 to 7.1 g correlates with an increase in the total ejected mass; ejecta angles, however, are similar in range for all experiments. The increase in projectile velocity from 2.5 to 5.1 km s-1 correlates with a total ejecta mass increase as well as in an increase in comminution efficiency, and a widening of the ejecta cone. A higher degree of water saturation of the target yields an increase in total ejecta mass up to 400% with respect to dry targets, higher ejecta velocity, and a steeper cone. These data, in turn, suggest that the reduced impedance contrast between the quartz grains of the target and the pores plays a primary role in the ejecta mass increase, while vaporization of water determines the ejecta behavior concerning ejecta velocity and particle distribution.

  8. Assessment of Left Ventricular Pre-Ejection Period in the Fetus Using Simultaneous Magnetocardiography and Echocardiography

    PubMed Central

    Mensah-Brown, Nana Aba; Wakai, Ronald T.; Cheulkar, Bageshree; Srinivasan, Shardha; Strasburger, Janette F.

    2010-01-01

    Introduction Fetal magnetocardiography (fMCG) is a promising new technique for assessing fetal rhythm; however, no prior studies have utilized fMCG to evaluate human fetal electromechanical physiology. Pre-ejection period (PEP) is an important measure of the electromechanical activation of the heart, and is altered by disease states and arrhythmias. Materials and Methods A novel technique was used to assess fetal PEP and its relationship to other fetal systolic time intervals, RR interval, and gestational age (GA). 25 normal human fetuses between 19 and 38 weeks' gestation were studied using simultaneous pulsed Doppler ultrasound and fMCG. Correlations among PEP, ejection time, QRS width and RR interval were assessed using linear regression. Results Across all subjects, PEP was found to correlate with GA (R = 0.57, p < 0.0001), QRS width (R = 0.35, p = 0.026), and RR interval (R = 0.37, p = 0.018). In individual sessions, PEP negatively correlated beat-to-beat with the preceding RR interval. Conclusion PEP exhibits developmental trends that provide a better understanding of the normal development of the human fetal heart. PMID:20975278

  9. Investigation of a clamshell roll-out ejection concept

    NASA Technical Reports Server (NTRS)

    Hatakeyama, L. F.

    1971-01-01

    The equations for the motion, forces, and couples generated by clamshells released from spinning sounding rockets in accordance with a roll-out ejection concept are presented. The application of these equations to a study of a system for the Javelin rocket vehicle is discussed. The roll-out ejection concept advocated requires that each deploying clamshell be pivoted about an axis at its trailing edge located in the system sectioning plane. Clamshell despinning is a consequence of this deployment since the pivotal rate is in opposition to the rocket vehicle spin. The energy required by the deployment is derived largely from the rotational energy of the clamshell. Thus, the rocket vehicle will not be significantly despun by this kind of clamshell deployment. This ejection concept also permits a system design which makes it possible to limit clamshell angular motion to rotation about that one of its centroidal principal axes which is brought into parallelism with the rocket vehicle longitudinal axis. Also, by equalizing the moments of inertia about the other centroidal principal axes, the roll-out motion can be decoupled from any extraneous angular motion about these axes.

  10. Effects of Slag Ejection on Solid Rocket Motor Performance

    NASA Technical Reports Server (NTRS)

    Whitesides, R. Harold; Purinton, David C.; Hengel, John E.; Skelley, Stephen E.

    1995-01-01

    In past firings of the Reusable Solid Rocket Motor (RSRM) both static test and flight motors have shown small pressure perturbations occurring primarily between 65 and 80 seconds. A joint NASA/Thiokol team investigation concluded that the cause of the pressure perturbations was the periodic ingestion and ejection of molten aluminum oxide slag from the cavity around the submerged nozzle nose which tends to trap and collect individual aluminum oxide droplets from the approach flow. The conclusions of the team were supported by numerous data and observations from special tests including high speed photographic films, real time radiography, plume calorimeters, accelerometers, strain gauges, nozzle TVC system force gauges, and motor pressure and thrust data. A simplistic slag ballistics model was formulated to relate a given pressure perturbation to a required slag quantity. Also, a cold flow model using air and water was developed to provide data on the relationship between the slag flow rate and the chamber pressure increase. Both the motor and the cold flow model exhibited low frequency oscillations in conjunction with periods of slag ejection. Motor and model frequencies were related to scaling parameters. The data indicate that there is a periodicity to the slag entrainment and ejection phenomena which is possibly related to organized oscillations from instabilities in the dividing streamline shear layer which impinges on the underneath surface of the nozzle.

  11. Droplet ejection and sliding on a flapping film

    NASA Astrophysics Data System (ADS)

    Chen, Xi; Doughramaji, Nicole; Betz, Amy Rachel; Derby, Melanie M.

    2017-03-01

    Water recovery and subsequent reuse are required for human consumption as well as industrial, and agriculture applications. Moist air streams, such as cooling tower plumes and fog, represent opportunities for water harvesting. In this work, we investigate a flapping mechanism to increase droplet shedding on thin, hydrophobic films for two vibrational cases (e.g., ± 9 mm and 11 Hz; ± 2 mm and 100 Hz). Two main mechanisms removed water droplets from the flapping film: vibrational-induced coalescence/sliding and droplet ejection from the surface. Vibrations mobilized droplets on the flapping film, increasing the probability of coalescence with neighboring droplets leading to faster droplet growth. Droplet departure sizes of 1-2 mm were observed for flapping films, compared to 3-4 mm on stationary films, which solely relied on gravity for droplet removal. Additionally, flapping films exhibited lower percentage area coverage by water after a few seconds. The second removal mechanism, droplet ejection was analyzed with respect to surface wave formation and inertia. Smaller droplets (e.g., 1-mm diameter) were ejected at a higher frequency which is associated with a higher acceleration. Kinetic energy of the water was the largest contributor to energy required to flap the film, and low energy inputs (i.e., 3.3 W/m2) were possible. Additionally, self-flapping films could enable novel water collection and condensation with minimal energy input.

  12. The Formation of Brown Dwarfs as Ejected Stellar Embryos

    NASA Astrophysics Data System (ADS)

    Reipurth, Bo; Clarke, Cathie

    2001-07-01

    We conjecture that brown dwarfs are substellar objects because they have been ejected from small newborn multiple systems that have decayed in dynamical interactions. In this view, brown dwarfs are stellar embryos for which the star formation process was aborted before the hydrostatic cores could build up enough mass to eventually start hydrogen burning. The disintegration of a small multiple system is a stochastic process, which can be described only in terms of the half-life of the decay. A stellar embryo competes with its siblings in order to accrete infalling matter, and the one that grows slowest is most likely to be ejected. With better luck, a brown dwarf would therefore have become a normal star. This interpretation of brown dwarfs readily explains the rarity of brown dwarfs as close companions to normal stars, the absence of wide brown dwarf binaries, and the flattening of the low-mass end of the initial mass function. Possible observational tests of this scenario include statistics of brown dwarfs near Class 0 sources and the kinematics of brown dwarfs in star-forming regions, while they still retain a kinematic signature of their expulsion. Because the ejection process limits the amount of gas brought along in a disk, it is predicted that substellar equivalents to the classical T Tauri stars should be rather short-lived.

  13. MAGNETOHYDRODYNAMIC MODELING FOR A FORMATION PROCESS OF CORONAL MASS EJECTIONS: INTERACTION BETWEEN AN EJECTING FLUX ROPE AND AN AMBIENT FIELD

    SciTech Connect

    Shiota, Daikou; Kusano, Kanya; Miyoshi, Takahiro; Shibata, Kazunari

    2010-08-01

    We performed a magnetohydrodynamic simulation of a formation process of coronal mass ejections (CMEs), focusing on the interaction (reconnection) between an ejecting flux rope and its ambient field. We examined three cases with different ambient fields: one had no ambient field, while the other two had dipole fields with opposite directions, parallel and anti-parallel to that of the flux rope surface. We found that while the flux rope disappears in the anti-parallel case, in the other cases the flux ropes can evolve to CMEs and show different amounts of flux rope rotation. The results imply that the interaction between an ejecting flux rope and its ambient field is an important process for determining CME formation and CME orientation, and also show that the amount and direction of the magnetic flux within the flux rope and the ambient field are key parameters for CME formation. The interaction (reconnection) plays a significant role in the rotation of the flux rope especially with a process similar to 'tilting instability' in a spheromak-type experiment of laboratory plasma.

  14. Zircon U-Pb ages and Sr-Nd-Hf isotopes of the highly fractionated granite with tetrad REE patterns in the Shamai tungsten deposit in eastern Inner Mongolia, China: Implications for the timing of mineralization and ore genesis

    NASA Astrophysics Data System (ADS)

    Jiang, Si-Hong; Bagas, Leon; Hu, Peng; Han, Ning; Chen, Chun-Liang; Liu, Yuan; Kang, Huan

    2016-09-01

    The Shamai tungsten deposit is located in the eastern part of the Central Asian Orogenic Belt (CAOB). Tungsten mineralization is closely related to the emplacement of fine- to medium-grained biotite monzogranite (G1) and porphyritic biotite monzogranite (G2) in the Shamai Granite. NW-trending joints and faults host orebodies in the Shamai Granite and Devonian hornfels. The mineralization is characterized by a basal veinlet zone progressing upwards to a thick vein zone followed by a mixed zone, a veinlet zone, and a thread vein zone at the top. The ore-related alteration typically consists of muscovite, greisen, and hornfels. In order to constrain the timing of the Shamai mineralization and discuss the ore genesis, muscovite Ar-Ar, molybdenite Re-Os, and zircon U-Pb geochronological, geochemical, and Sr-Nd-Hf isotopic studies were completed on the deposit. The U-Pb zircon dating yielded weighted mean ages of 153 ± 1 Ma for G1 and 146 ± 1 Ma for G2. Muscovite from a wolframite-bearing quartz vein yielded an Ar-Ar plateau age of 140 ± 1 Ma, whereas two molybdenite samples yielded identical Re-Os model ages of 137 ± 2 Ma. These two ages are younger than the two monzogranites, suggesting a prolonged magmatic-hydrothermal interaction during tungsten mineralization. Major and trace element geochemistry shows that both G1 and G2 are characterized by high SiO2 and K2O contents, high A/CNK values (1.08-1.40), a spectacular tetrad effect in their REE distribution patterns, and non-CHARAC (charge-and-radius-controlled) trace element behavior. This suggests that both G1 and G2 are highly differentiated peraluminous rocks with strong hydrothermal interaction. The Nd-Hf isotope data for the Shamai Granite (εNd(t) between - 1.9 and + 7.4, ɛHf(t) from 5.2 to 12.8) are largely compatible with the general scenario for much of the Phanerozoic granite emplaced in the CAOB. It is here suggested that the Shamai Granite originated from partial melting of a juvenile lower crust with

  15. Maximum Velocity of a Boulder Ejected From an Impact Crater Formed on a Regolith Covered Surface</