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Off-pump pulmonary valve replacement with the new Shelhigh Injectable Stented Pulmonic Valve
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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
Important excess morbidity due to upper airway anomalies in the perioperative course in infant cardiac surgery
No full textBACKGROUND: The study aimed at defining the excess morbidity or mortality caused by an additional airway malformation in children with congenital heart disease requiring surgery. METHODS: All patients requiring surgery for heart disease during an 8-year period ending in 2003 who had an associated upper airway malformation were retrospectively studied. All patients were seen in 2004 for a prospective follow-up examination. RESULTS: Eleven patients with upper airway anomalies were identified (tracheobronchial malacia in 6 patients, long-segment tracheal stenosis in 3, and bilateral vocal cord paralysis and tracheal hemangioma in 1 patient each). They accounted for 1.5% of the entire cardiac surgical load of 764 patients. In 5 infants, the airway anomaly was diagnosed before cardiac repair, in 6 patients thereafter. Diagnosis was made by bronchoscopy in all patients, by additional bronchography in 2. Failure of rapid postoperative extubation was the most common finding. Airway management was surgical in 2 and conservative in 8 patients, 1 newborn having been denied therapy because of the severity of airway hypoplasia. Compared with patients with isolated cardiac disease, those with additional airway anomalies had significantly longer duration of postoperative mechanical ventilation (median, 24 days versus 3), perioperative hospitalization (median, 72 days versus 11) and total number of days of hospitalization during the first year of life (median, 104 days versus 14). After a maximum follow-up of 8 years (median, 37 months) only 3 of 10 surviving patients remained symptomatic owing to the airway malformation. CONCLUSIONS: Upper airway anomalies accompanying heart disease in infancy resulted in a significant prolongation of perioperative intensive care and hospital stay, as well as duration of mechanical ventilation. Failure of early postoperative extubation was the leading symptom
Off-pump coronary artery bypass operation does not increase procoagulant and fibrinolytic activity: preliminary results
No full textBACKGROUND: This study analyzes the effects on coagulation and fibrinolysis comparing off-pump coronary artery bypass (OPCAB) and on-pump CABG operations. METHODS: In a prospective, nonrandomized, comparative evaluation, patients scheduled for elective myocardial revascularization were studied. Due to possible confounding factors patients with postoperative retransfusion of mediastinal shed blood were excluded. Nine patients underwent OPCAB operation and 16 underwent on-pump CABG. Activated clotting time (ACT) was adjusted to 250 seconds in OPCAB (81 +/- 18 [mean +/- SD] IU/kg heparin) and to more than 480 seconds in on-pump CABG (400 IU/kg heparin, additional 10,000 IU in pump prime). Perioperatively blood samples were collected and hematologic and hemostatic variables including fibrinopeptide A (FPA), fibrin monomer (FM), thrombin-antithrombin complex (TAT), and D-dimer were analyzed. RESULTS: Both groups showed comparable demographic variables. Number of grafts per patient was slightly higher in the on-pump group (3.6 +/- 0.6 versus 3.0 +/- 1.1, p = 0.23). The FPA levels did not differ significantly between the groups. The FM, TAT, and D-dimer values were significantly higher in on-pump CABG (p < 0.0001, p < 0.01, and p < 0.0001, respectively), reflecting increased coagulant and fibrinolytic activity. This was also the case when values were corrected for hemodilution. CONCLUSIONS: Despite lower systemic anticoagulation activation of coagulation and fibrinolysis is reduced in OPCAB compared with on-pump CABG. Reduced thrombin generation and reduced fibrinolytic activity in OPCAB indicates better preservation of hemostasis. We suggest the term "preserved hemostasis" instead of "hypercoagulant activity" with respect to OPCAB
Risk factors for secondary dilatation of the aorta after acute type A aortic dissection
Full text linkObjectives: Prompt diagnosis of subsequent dilatation of the dissected aorta is crucial to reduce late mortality in these patients. This study focuses on risk factors for dilatation of the aorta after type A aortic dissection (AADA) affecting a normal-sized or slightly dilated aorta. Methods: Overall 531 CT scans were analysed. Patients were included in the study if at least 3 CT scans were available after operative repair. 64 patients (59.8%) out of 107 patients full-field the inclusion criteria. Volumetric analyses of the aorta were performed. Patients were divided in 3 groups: group A included 26 patients (40.6%) without progression of the aortic diameter, group 2, 27 patients (42.2%) with slight progression and group 3, 11 patients (17.2%) with important progression, requiring surgery in 9 patients (81.8%). Risk-factors for progression of the aortic size were analysed and compared between the groups. Results: Patients from group 3 were younger 57.7±13.4 vs. 61.9±11.6 in group 1 (P≪0.05) and were more frequent female (45.4 vs. 23.1%; P≪0.05). Dissection of the supraaortic branches (100 vs. 80.8%; P≪0.05), the presence of preoperative cerebral, visceral or peripheral malperfusion (54.6 vs. 26.9%; P≪0.05) and contrast enhancement in the false lumen during the follow-up (72.7 vs. 57.7%; P=0.07) were additional risk factors for late aortic dilatation in these patients. Conclusions: Acute type A aortic dissection in younger patients, involving the supraaortic branches and/or combined with malperfusion syndrome favour secondary dilatation. A close follow-up is mandatory to prevent acute complications of the diseased downstream aorta following repair of a AADA
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
Impact of clopidogrel in coronary artery bypass grafting
Full text linkObjective: Clopidogrel has become the standard of care to prevent thrombotic complications following cardiological interventions, in particular intracoronary stenting. In addition, patients with aspirin intolerance and those with carotid and peripheral vascular disease are also increasingly treated with clopidogrel. Platelet inhibition may become a concern for hemostasis in patients treated with clopidogrel who need emergency and undelayed surgery. Methods: We prospectively analyzed the intra- and postoperative outcome of 505 consecutive patients who underwent isolated CABG and compared two groups: those with clopidogrel exposure until 72 h prior to surgery (n=136) with those without exposition to clopidogrel (n=369). Patients undergoing emergency surgery because of failed PTCA and cardiogenic shock, associated valvular surgery, redo-CABG, and those with additional platelet IIb/IIIa receptor inhibitor exposure were excluded. Patients who received aspirin and/or heparin treatment prior to surgery were not excluded. Results: Patients who received clopidogrel had a higher prevalence of angina class III or IV (67 vs 39%, P<0.01), received more often revascularization within 48 h (41 vs 14%, P=0.02), and had received more frequently stenting (57 vs 13%). Chest tube drainage was significantly increased during the first 24 h following CABG in the group of patients who had clopidogrel treatment (1485 vs 780 ml, P=0.003) These patients also required more transfusion of platelets and fresh frozen plasma. Overall re-exploration rate because of bleeding was significantly higher in the clopidogrel group (5.9 vs 1.2%, P<0.01). Platelets transfused before chest closure had a beneficial effect on preservation of the hemostasis. Conclusions: Clopidogrel exposure 3 days or less prior to CABG surgery significantly increases the risk of postoperative bleeding, the need for perioperative transfusion and the incidence of re-exploration. Surgery should be performed using standard heparinization and anti-fibrinolytic strategies but aggressive correction of platelets dysfunction is required before chest closure
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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