1,720,963 research outputs found
Prognostic significance of early q wave in the course of STEMI
No full textDuring STEMI, the presence of early Q wave in infarction leads can be frequently found in clinical practice. The occurrence of an early Q wave would be associated with an increased mortality as an expression of a more extensive myocardial damage. The aim of our study was to evaluate how the presence of the Q wave at the time of the STEMI presentation correlates with infarct size, the early complications and mortality during hospital stay.
Materials and Methods: From January 1st 2009 to December 31st 2014 , 248 consecutive patients with pre-hospital diagnosis of STEMI and who had primary angioplasty within 12 hours of symptom onset were transported from Emergency System to our CCU. Patients were divided into two groups based on the presence of necrosis Q wave in infarction leads at first ECG made on site of the event: group Q-wave (QWG) with 44 patients and group No Q-wave (NQWG) composed of 204 patients. For each patient demographic data, clinical variables, instrumental and laboratory examinations were collected, infarct size was evaluated according to the CPK peak value , ejection fraction ( EF) was calculated on admission , and total ischemic time (TIT) was calculated as time from symptom onset to reperfusion.
Results: The QWG had a worse EF on admission to the CCU than NQWG (47% ± 17.8 vs 53.8 ± 5.9%, p = 0.00001); greater total CPK peak (3330 IU / L ± 2803.4 vs 2312 IU / L ± 2561.2, p = 0.02). The average hospital stay was significantly longer in the QWG than in NQWG (9.95 ± 7.83 vs 5.3 ± 3.2 days, 0.0013). Finally, the hospital mortality was 9% in the QWG compared to 1.9% in the NQWG (p = 0.015). The percentage of patients with a TIT≤ 120 minutes did not differ between groups (13.6% vs 21.6%, p = 0:23). At the Cox multivariate analysis age (p = 0.005), the CPK peak (p=0.03) and presence of early Q waves (p = 0.017) were independent predictors of mortality during hospital stay.
Conclusions: The pathological Q wave may appear early in the acute phase of STEMI. Our data confirm that the presence of Q wave in the early stages of STEMI is a predictor of adverse clinical outcomes regardless of the duration of total ischemic time and this parameter can be used as an indicator of evolving stage of the acute myocardial infarction
Relationship Between The First Diagnostic Ecg And Time To The Start Of Symptoms In Acute Myocardial Infarction
No full textQ wave is typically a late finding on ECG during STEMI and consequently, when Q wave is found on the first ECG, many patients do not receive reperfusion therapy. In reality, the Q wave can also appear early in the course of the infarct and may represent a large reversible myocardial damage. The aim of our study was to evaluate the association between ischemic time and the appearance of the Q wave in STEMI acute phase and to assess whether the presence of an early Q wave can affect the management of STEMI patients. Materials and Methods: From January 1st 2009 to December 31st 2014, 248 consecutive patients with STEMI were transported from Emergency System to our CCU. Patients were divided into two groups based on the presence of Q wave in infarction leads at first ECG: group Q-wave (QWG) with 44 patients and group No Q-wave (NQWG) composed of 204 patients. For each patient following intervals were calculated: - the time between pain onset and first ECG (pain to ECG time ); - the time between the first ECG and the first intervention that restored the necrosis vessel patency (first medical contact-to-balloon time, FMC);- The time from the arrival of the patient to the hospital, and the reopening of the necrosis vessel (door-to-balloon time, DTB). Results: Pain to ECG time was greater in patients with Q-wave (119 ± 97 vs 113.02 ± 92.6 minutes, p = 0:09). The percentage of patients with early Q-wave increased progressively with increasing pain to ECG time from 2.5% in patients with Pain to ECG less than 30 minutes to 11.6% and 18.2% respectively in patients with Pain-to-ECG more than two hours and four hours (p for trend = 0.011). The DTB time, was quite comparable in both groups, 55 ± 54 vs 24.6 ± 31.2 min, p = 0.9. The FMC did not present statistically significant differences between groups (102.2 ± 35.9 minutes vs 97.8 ± 40.05 minutes, p = 0.48). Conclusions: The appearance of the Q wave is a time dependent phenomenon and is therefore affected by the delay between the onset of ischemia and the performing ECG, with a tendency to be present even in the earliest stages of the infarct itself. Despite the presence of Q waves at the first diagnostic ECG, management standard protocol of STEMI was applied in all patients, ensuring the similar reperfusion times
Prognosis and first diagnostic ECG in STEMI patients referred to the emergency medical system for primary PCI
No full textBackground: Pathological Q waves (QWs) in the first ECG recorded at hospital admission has been found to correlate with myocardial damage and mortality in STEMI patients. We investigated the association between new QWs recorded in the pre-hospital setting and adverse outcome during the hospital stay. Methods: A pre-hospital ECG was recorded in 248 patients with STEMI who underwent primary PCI. Patients were divided into two groups based on the presence (n = 44, QWs) or absence (n = 204, non-QWs) of new QWs. Results: Patients with new QWs had a higher prevalence of anterior infarct, cardiogenic shock and a lower LV ejection fraction. In-hospital mortality was higher in patients with new QWs. The percentage of patients with new QWs increased progressively with increasing pain to ECG time. Conclusions: New QWs provide rapid prognostic information in the pre-hospital phase of STEMI by identifying patients at risk of adverse outcome during the hospital stay
Role of speckle tracking in predicting arrhythmic risk and occurrence of appropriate implantable defibrillator Intervention in patients with ischemic and non-ischemic cardiomyopathy
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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
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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