1,721,013 research outputs found
Diuretic Therapy for Patients With Heart Failure JACC State-of-the-Art Review
No full textExpansion of extracellular fluid volume is central to the pathophysiology of heart failure. Increased extracellular fluid leads to elevated intracardiac filling pressures, resulting in a constellation of signs and symptoms of heart failure referred to as congestion. Loop diuretics are one of the cornerstones of treatments for heart failure, but in contrast to other therapies, robust clinical trial evidence to guide the use of diuretics is sparse. A nuanced understanding of renal physiology and diuretic pharmacokinetics is essential for skillful use of diuretics in the management of heart failure in both the inpatient and outpatient settings. Diuretic resistance, defined as an inadequate quantity of natriuresis despite an adequate diuretic regimen, is a major clinical challenge that generally portends a poor prognosis. In this review, the authors discuss the fundamental mechanisms and physiological principles that underlie the use of diuretic therapy and the available data on the optimal use of diuretics.Felker, GM (reprint author), Duke Clin Res Inst, 200 Morris St, Durham, NC 27705 USA.
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Altered Hemodynamics and End-Organ Damage in Heart Failure Impact on the Lung and Kidney
No full textHeart failure is characterized by pathologic hemodynamic derangements, including elevated cardiac filling pressures ("backward" failure), which may or may not coexist with reduced cardiac output ("forward" failure). Even when normal during unstressed conditions such as rest, hemodynamics classically become abnormal during stressors such as exercise in patients with heart failure. This has important upstream and downstream effects on multiple organ systems, particularly with respect to the lungs and kidneys. Hemodynamic abnormalities in heart failure are affected by processes that extend well beyond the cardiac myocyte, including important roles for pericardial constraint, ventricular interaction, and altered venous capacity. Hemodynamic perturbations have widespread effects across multiple heart failure phenotypes, ranging from reduced to preserved ejection fraction, acute to chronic disease, and cardiogenic shock to preserved perfusion states. In the lung, hemodynamic derangements lead to the development of abnormalities in ventilatory control and efficiency, pulmonary congestion, capillary stress failure, and eventually pulmonary vascular disease. In the kidney, hemodynamic perturbations lead to sodium and water retention and worsening renal function. Improved understanding of the mechanisms by which altered hemodynamics in heart failure affect the lungs and kidneys is needed in order to design novel strategies to improve clinical outcomes.Dr Verbrugge is supported by a Fellowship of the Belgian American Educational Foundation and by the Special Research Fund of Hasselt University (grant no. BOF19PD04). Dr Borlaug is supported by grants R01 HL128526 and U01 HL125205, both from the US National Heart, Lung, and Blood Institute.Borlaug, BA (corresponding author), Mayo Clin & Mayo Fdn, 200 First St SW, Rochester, MN 55905 USA.
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Different diuretic dose and response in acute decompensated heart failure: Clinical characteristics and prognostic significance
No full textBackground The question regarding the correct balance between optimal loop diuretic dose administration and best modality is under debate as well as the exact relation existing between congestion and renal dysfunction. We sought to evaluate the effects of different diuretic modalities (low [LD] versus high dose [HD]) and dose administration on decongestion, Worsening renal function (WRF) and outcome. Methods We retrospectively analyzed data of DIUR-HF study matching for LD vs HD (cut off 125 mg/day), and diuretic efficiency (DE) (weight loss/40 mg daily of furosemide). We also evaluated WRF rate (creatinine increase during hospitalization ≥ 0.3 mg/dl or estimated glomerular filtration rate (eGFR) reduction ≥ 25%) together with decongestion. Results HD patients (n.55) were older, more frequently affected by diabetes and chronic kidney disease (CKD) and demonstrated higher rate of inhospital WRF (65% vs 29% p = 0.001) and 180-days adverse events (70% vs 23% p < 0.001) respect to LD patients (n.41). Patients with low DE showed a higher 180 days adverse events rate than higher DE patients (p = 0.02). Univariate and multivariable analysis suggests a significant relationship between adverse events and low DE (patients with DE under median value) (U-HR = 2.59 [1.44–4.64]; p = 0.001. M-HR = 3.16 [1.55–6.46]; p = 0.002); continuous administration (HR = 3.12 [1.65–5.91]; p < 0.001) and WRF (HR = 5.30 [2.79–10.09]; p < 0.001) were also related with adverse events. Conclusions HD and poor DE are two conditions associated with adverse outcome. Both situations are the consequence of previous detrimental clinical status and they appear strictly related to WRF occurrence
Measures of Loop Diuretic Efficiency and Prognosis in Chronic Kidney Disease
No full textBackground: The evolution and prognostic impact of loop diuretic efficiency according to chronic kidney disease (CKD) severity is unclear. Methods: This retrospective cohort study includes 783 CKD patients on oral loop diuretic therapy with a 24-h urine collection available. Acute kidney injury and history of renal replacement therapy were exclusion criteria. Patients were stratified according to Kidney Disease Improving Global Outcomes (KDIGO) glomerular filtration rate class. Loop diuretic efficiency was calculated as urine output, natriuresis, and chloruresis, each adjusted for loop diuretic dose, and compared among strata. Risk for onset of dialysis and all-cause mortality was evaluated. Results: Loop diuretic efficiency metrics decreased from KDIGO class IIIB to IV in furosemide users and from KDIGO class IV to V with all loop diuretics (p value <0.05 for all comparisons). The correlation between loop diuretic efficiency and creatinine clearance was moderate at best (Spearman's rho 0.298-0.436; p value <0.001 for all correlations). During median follow-up of 45 months, 457 patients died (58%) and 63 received kidney transplantation (8%), while dialysis was started before in 328 (42%). All loop diuretic efficiency metrics were significantly and independently associated with both the risk for dialysis and all-cause mortality. In KDIGO class IV/V patients, low loop diuretic efficiency (i.e., urine output adjusted for loop diuretic dose <= 1,000 mL) shortened median time to dialysis with 24 months and median time to all-cause mortality with 23 months. Conclusion: Low loop diuretic efficiency is independently associated with a shorter time to dialysis initiation and a higher risk for all-cause mortality in CKD.F.H.V. is supported by a Fellowship of the Belgian American Educational Foundation and by the Special Research Fund (BOF) of Hasselt University (BOF19PD04).Verbrugge, FH (corresponding author), Univ Hosp Leuven, Dept Nephrol, Herestr 49, BE-3000 Leuven, Belgium.
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Insufficient Natriuretic Response to Continuous Intravenous Furosemide Is Associated With Poor Long-Term Outcomes in Acute Decompensated Heart Failure
No full textBackground: Treatment of acute decompensated heart failure (ADHF) with loop diuretics, such as furosemide, is frequently complicated by insufficient urine sodium excretion. We hypothesize that insufficient natriuretic response to diuretic therapy, characterized by lower urine sodium (U-Na) and urine furosemide, is associated with subsequent inadequate decongestion, worsening renal function, and adverse long term events. Methods and Results: We enrolled 52 consecutive patients with ADHF and measured serum and urine sodium (U-Na), urine creatinine (U-Cr), and urine furosemide (U-Furosemide) levels on a spot sample taken after treatment with continuous intravenous furosemide, and followed clinical and renal variables as well as adverse long-term clinical outcomes (death, rehospitalizations, and cardiac transplantation). We observed similar correlations between U-Na:U-Furosemide ratio and U-Na and fractional excretion of sodium (FENa) with 24-hour net urine output (r = 0.52-0.64, all P < .01) and 24-hour weight loss (r = 0.44-0.56; all P < .01). Interestingly, FENa (but not U-Na or U-Na:U-Furosemide) were influenced by estimated glomerular filtration rate (eGFR). We observed an association between lower U-Na:U-Furosemide with greater likelihood of worsening renal function (hazard ratio [HR] 3.01; P = .02) and poorer adverse clinical outcomes (HR 1.63, P = .008) after adjusting for age and eGFR. Meanwhile, both diminished weight loss and net fluid output over 24 hours of continuous intravenous furosemide were observed when U-Na:U-Furosemide ratios were <2 mmol/mg or when U-Na <50 mmol. Conclusion: In patients with ADHF receiving continuous furosemide infusion, impaired natriuretic response to furosemide is associated with greater likelihood of worsening renal function and future adverse long-term outcomes, independently from and incrementally with decreasing intrinsic glomerular filtration.This research was supported by grant funding from the National Institutes of Health (R01HL103931 [W.T.] and K23HL114868 [J.T.]) and the Cleveland Clinic Clinical Research Unit of the Case Western Reserve University CTSA (UL1TR 000439)
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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