1,721,157 research outputs found
Complete revascularization during primary percutaneous coronary intervention reduces death and myocardial infarction in patients with multivessel disease. meta-analysis and meta-regression of randomized trials
No full textOBJECTIVES The aim of this study was to compare complete revascularization with a culprit-only strategy in patients presenting with ST-segment elevation myocardial infarction (MI) and multivessel disease by a meta-analysis of randomized trials.
BACKGROUND Although several trials have compared complete with culprit-only revascularization in ST-segment elevation MI, it remains unclear whether complete revascularization may lead to improvement in hard endpoints(death and MI).
METHODS Randomized trials comparing complete revascularization with culprit-only revascularization in patients with ST-segment elevation MI without cardiogenic shock were identified by a systematic search of published research. Random-effects meta-analysis was performed, comparing clinical outcomes in the 2 groups.
RESULTS Eleven trials were identified, including a total of 3,561 patients. Compared with a culprit-only strategy, complete revascularization significantly reduced risk for death or MI (relative risk [RR]: 0.76; 95% confidence interval [CI]: 0.58 to 0.99; p 1⁄4 0.04). Meta-regression showed that performing complete revascularization at the time of primary percutaneous coronary intervention (PCI) was associated with better outcomes (p 1⁄4 0.016). The 6 trials performing complete revascularization during primary PCI (immediate revascularization) were associated with a significant reduction in risk for both total mortality (RR: 0.62; 95% CI: 0.39 to 0.97; p 1⁄4 0.03) and MI (RR: 0.40; 95% CI: 0.25 to 0.66; p < 0.001), whereas the 5 trials performing only staged revascularization did not show any significant benefit in either total mortality (RR: 1.02; 95% CI: 0.65 to 1.62; p 1⁄4 0.87) or MI (RR: 1.04; 95% CI: 0.48
to 1.68; p 1⁄4 0.86).
CONCLUSIONS When feasible, complete revascularization with PCI can significantly reduce the combined endpoint of death and MI. Complete revascularization performed during primary PCI was also associated with significant reductions in both total mortality and MI, whereas staged revascularization did not improve these outcomes.(J Am Coll Cardiol Intv 2018;11:833–43) © 2018 by the American College of Cardiology Foundation
Meta-analysis of randomized trials comparing the effectiveness of different strategies for the treatment of drug-eluting stent restenosis
No full textThe investigators performed a network meta-analysis of randomized trials comparing the effectiveness of currently available strategies for the treatment of drug-eluting stent (DES) restenosis. Despite the widespread use of DES in patients who undergo percutaneous coronary intervention, the optimal treatment for DES restenosis remains poorly defined. A systematic search of electronic resources was performed. The primary end point was diameter stenosis at follow-up angiography. Seven trials were included, enrolling a total of 1,586 patients with 1,728 restenotic lesions. The following treatment options were found: balloon angioplasty (BA) in 343 patients (19.3%), iopromide-based paclitaxel-eluting balloons (PEB) in 343 (21.6%), sirolimus-eluting stents in 441 (27.8%), paclitaxel-eluting stents in 462 (29.1%), and everolimus-eluting stents in 34 (2.2%). Compared with BA, PEB (-17.74%, 95% credible interval [CI] -25.17% to -11.31%), everolimus-eluting stents (-14.93%, 95% CI -33.47% to 1.16%), paclitaxel-eluting stents (-15.3%, 95% CI -22.96% to -8.35%), and sirolimus-eluting stents (-11.08%, 95% CI -17.89% to -3.4%) had similar reductions in diameter stenosis at follow-up angiography. PEB (85%) and everolimus-eluting stents (68%) had the greatest probabilities for being the best treatment option. Furthermore, PEB were the best treatment in terms of late luminal loss (85%) and binary restenosis (85%). BA had the lowest efficacy with respect to all study end points. In conclusion, in patients with DES restenosis, repeat DES implantation and iopromide-based PEB are valid alternatives. However, PEB had greater angiographic efficacy and therefore should be considered the new benchmark comparator in the treatment of DES restenosis. The use of BA should be discouraged in patients with DES restenosis
Net clinical benefit of patent foramen ovale closure in patients with cryptogenic stroke. meta-analysis and meta-regression of randomized trials
No full textBackground: Controlled randomized trials (CRTs) comparing the efficacy of patent foramen ovale (PFO) closure and medical therapy in patients with cryptogenic stroke have yielded heterogeneous results. No data are available on the net clinical benefit with the two strategies.
Methods: We pooled data of 3440 patients enrolled in five CRTs, randomized to PFO closure (n = 1829) or medical therapy (n=1611) and followed for a mean of 4.1 years.
Results: The net composite endpoint of stroke, major bleeding or atrial fibrillation (AF)/flutter was not different among PFO closure and medical therapy (OR 1.06; 95% CI 0.63–1.77; p = 0.83). PFO closure was associated with similar bleeding rates and with a significant 59% relative reduction of recurrent stroke versus medical therapy; in the intervention group this stroke prevention was counterbalanced by a significant 4.7-fold higher
risk of AF/flutter. Meta-regression analysis showed that odds ratios for the net composite endpoint were related to prevalence of severe shunt at baseline (p = 0.002), percentage of procedural success (p = 0.002), stroke
incidence in the medical therapy arm (p=0.012) and to follow-up duration (p=0.001).
Conclusions: This study-levelmeta-analysis of CRTs demonstrates that, compared tomedical therapy, PFOclosure prevents recurrent ischemic cerebral events, but increases the risk of AF/flutter in patients with cryptogenic stroke; as a result, the net clinical benefit with the two strategies was similar. Our results support an individualized therapeutic approach, tailored on the evaluation of the patient's risks (anatomical PFO risk, clinical risk of recurrent stroke, bleeding risk, and risk of AF)
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
- …
