1,720,959 research outputs found
Unusual association of left ventricular diverticulum and hypertrophic cardiomyopathy in an adult.
No full textA 68-year-old female with hypertrophic obstructive cardiomyopathy (HOCM), fibrous subaortic stenosis, mitro-aortic valve insufficiencies, and congenital left ventricular diverticulum (CLVD) at apical level was diagnosed after syncope. Although the association between HOCM and CLVD has been previously reported, no case has ever been disclosed in advanced adulthood
Leukocyte filtration of blood cardioplegia attenuates myocardial damage and inflammation.
No full textOBJECTIVES: Leukocyte filtration of blood cardioplegia (cLkF) is postulated to reduce ischaemia-reperfusion myocardial injury. Contradictory results have been published and few studies have addressed perioperative cytokine leakage and haemodynamic status after LkF.
METHODS: Thirty patients undergoing isolated aortic valve replacement were randomized to cLkF (cLkF-Group) or to standard cold blood cardioplegia (S-Group). Troponin I (TnI) and lactate were sampled from the coronary sinus at reperfusion. Peripheral TnI and lactate were collected preoperatively at admission, and in the intensive care unit (ICU) at 8, 12, 36 and 60 h postoperatively. Cardiac index (CI), indexed systemic vascular resistances, cardiac cycle efficiency (CCE) and central venous pressure (CVP) were registered preoperatively, at admission to the ICU and at the 6th, 12th, 18th, 24th and 36th postoperative hour. IL-6, IL-8, TNF-alpha and IL-10 were sampled preoperatively, at reperfusion, on admission to the ICU and the 6th, 18th and 24th postoperative hours.
RESULTS: The cLkF group showed lower TnI (2.4 ± 0.4 vs. 5.1 ± 0.8 μg/l, P = 0.0001) and lactate (0.9 ± 0.1 vs. 1.6 ± 0.2 mmol/l, P = 0.0001) from the coronary sinus at reperfusion. TnI levels (group-P = 0.0001, group time-P < 0.0001) and lactate (group time-P = 0.001) remained lower postoperatively after cLkF. Ventricular defibrillation at aortic declamping was less common in the cLkF-Group (33.3% vs. S-Group: 93.3%; P = 0.002). Cytokines demonstrated significant postoperative leakage (time-P = 0.0001 in both groups for IL-6, IL-8, TNF-alpha, IL-10), with lower pro-inflammatory (IL-6 group-P = 0.0001, group time-P = 0.0001; IL-8 group-P = 0.0001, group time-P = 0.007; TNF-alpha group-P = 0.0001; group time-P = 0.012) and higher anti-inflammatory cytokine secretion after cLkF (IL-10 group-P = 0.005). Perioperative haemodynamic indices proved to be similar between the two groups (group-P = NS for CI, SVRI, CCE and CVP).
CONCLUSIONS: cLkF during blood cardioplegia attenuates myocardial ischaemia/reperfusion injury and reduces perioperative leakage of TnI, lactate and pro-inflammatory cytokines. These data did not result in a better haemodynamic status
How should I wean my next intra-aortic balloon pump? Differences between progressive volume weaning and rate weaning.
No full textOBJECTIVE: Although the intra-aortic balloon pump is the most used ventricular assist device, no study has ever evaluated the best weaning method. We compared 2 different intra-aortic balloon pump weaning methods.
METHODS: Thirty consecutive patients needing an intra-aortic balloon pump because of perioperative low-output cardiac syndrome were randomized to be weaned by ratio (4 consecutive hours of a 1:2 assisting ratio followed by 1 hour of a 1:3 ratio; group R) or by progressive volume deflation (10% of total volume every hour for 5 consecutive hours; 15 patients, group V). A duration of 5 hours was set a priori as the weaning duration. The weaning protocol was started when the cardiac index was greater than 2.5 L/min/m(2), the central venous pressure was 12 mm Hg or less, the blood lactate was less than 2.5 mmol/L, the mean arterial pressure was greater than 65 mm Hg, and the preserved urine output (≥1 mL/kg/hr) lasted for at least 5 consecutive hours before weaning. The cardiac index, indexed systemic vascular resistance, cardiac cycle efficiency, and central venous pressure were registered at 9 points (T0, start; T1 to T5, the first 5 weaning hours; T6, 2 hours after withdrawal; T7, 12 hours after withdrawal; and T8, at intensive care unit discharge) using the pressure recording analytical method. The interval from intra-aortic balloon pump withdrawal to intensive care unit discharge, weaning failure, perioperative troponin I, and lactate (same points) were compared.
RESULTS: All patients, except for 1 belonging to group R (P = 1.0), were successfully weaned. Group V had better preserved cardiac index, indexed systemic vascular resistance, cardiac cycle efficiency, and central venous pressure (group*time P = .0001). Group R had worse cardiac index from T5 to T8 (P ≤ .0001), indexed systemic vascular resistance from T2 to T8 (P ≤ .004), cardiac cycle efficiency from T3 to T8 (P ≤ .001), central venous pressure from T4 to T8 (P ≤ .0001), and a longer interval from intra-aortic balloon pump withdrawal to intensive care unit discharge (P = .0001). The lactate level was lower in group V from T5 to T8 (P ≤ .027; group*time P = .001).
CONCLUSIONS: Intra-aortic balloon pump weaning by volume deflation allowed better hemodynamic and metabolic parameters
Renal cell carcinoma with invasion of the tricuspid valve apparatus
No full textA right atrial in-growth of renal carcinoma occurs in 1% of cases. A traditional approach to removal of the tumor using cardiopulmonary bypass (CPB) and deep-hypothermic circulatory arrest (DHCA) has been challenged in favor of techniques that allow tumor removal without CPB and DHCA. To the best of the present authors' knowledge, no report has yet been made of an invasion by the tumor of the tricuspid valve leaflets and subvalvular apparatus. The details of such a case are reported herein, where CPB + DHCA was used to completely remove the neoplasm, and to preserve tricuspid valve competence
Renal cell carcinoma with invasion of the tricuspid valve apparatus.
No full textA right atrial in-growth of renal carcinoma occurs in 1% of cases. A traditional approach to removal of the tumor using cardiopulmonary bypass (CPB) and deep-hypothermic circulatory arrest (DHCA) has been challenged in favor of techniques that allow tumor removal without CPB and DHCA. To the best of the present authors' knowledge, no report has yet been made of an invasion by the tumor of the tricuspid valve leaflets and subvalvular apparatus. The details of such a case are reported herein, where CPB + DHCA was used to completely remove the neoplasm, and to preserve tricuspid valve competence
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
- …
