1,721,006 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
OBSERVANT II: Studio osservazionale per la valutazione di efficacia delle procedure transcatetere con dispositivi di nuova generazione nel trattamento della stenosi aortica sintomatica severa. Protocollo di studio
BACKGROUND:
The rapid spread of transcatheter aortic valve implantation (TAVI) for the treatment of severe symptomatic aortic stenosis in the last decade in Italy has led to a gradually increasing use of TAVI procedures also in patients potentially eligible for aortic valve replacement (AVR). For this subset of patients, the OBSERVANT study (2011-2012) evaluated the short- and medium term outcome of TAVI vs AVR, at least for the first generations of TAVI devices, but failed to gather information on all the technological innovations occurred in recent years. The launch of a phase II of the study will allow to recruit a new series of TAVI, with different risk profiles compared with the historical OBSERVANT TAVI cohort, in order to assess whether and how much the use of new-generation devices mitigate the differences in outcomes recorded in the OBSERVANT study.
METHODS:
OBSERVANT II is an observational multicenter, prospective, cohort study collecting data on patients with severe symptomatic aortic stenosis undergoing TAVI in Italian hospitals since December 15, 2016, for at least 12 months. For each patient, data on demographic characteristics, health status, type of intervention and presence of comorbidities will be collected. Mortality and incidence of in-hospital major adverse cardiac and cerebrovascular events (MACCE) within 36 months of intervention will be the primary adverse outcome. Secondary outcomes will include 30-day mortality and the incidence of MACCE at 12 and 24 months. The statistical hypotheses were formulated considering the results from the OBSERVANT study. Testing these hypotheses will require the recruitment of at least 823 new TAVI. The risk/propensity-adjustment techniques will be used to comparatively evaluate the effectiveness of TAVI vs AVR.
EXPECTED RESULTS:
Safety and efficacy profiles of the new-generation TAVI prosthesis; comparative effectiveness of the new TAVI prosthesis as compared to TAVI procedures of the OBSERVANT historical cohort; comparative effectiveness of the new TAVI prosthesis as compared to AVR procedures of the OBSERVANT historical cohort.
CONCLUSIONS:
The results of OBSERVANT II will provide information on the effectiveness of TAVI employing new-generation devices and will be a valuable support to give professionals and policy makers evidence-based results useful for decision-making processes
Reply: TAVI in Lower Risk Patients: Revolution or Nonsense? Keep Calm and Select Patients
We read with interest the comments by Dr. Spadaccio and colleagues regarding the results of the OBSERVANT (Italian Observational Multicenter Registry) study, and we thank them for giving us the opportunity to clarify some of the issues raised in their letter. First, we would like to emphasize that OBSERVANT is a prospective observational study that enrolled consecutive patients with severe aortic stenosis treated with either surgical aortic valve replacement (SAVR) or transcatheter aortic valve implantation (TAVI) at 93 Italian centers between December 2010 and June 201
Five-Year Multiple Comparison of Transcatheter Aortic Valves: Insights From the OBSERVANT II study
Background: Head-to-head comparisons of second and third generations of transcatheter heart valves (THVs) are mostly limited to 2-arm studies and to mid-term follow-up. The aim of this study was to simultaneously compare clinical outcomes of transcatheter aortic valve replacement (TAVR) with 4 different THVs at 5 years. Methods: Patients undergoing transfemoral TAVR with 4 second-generation THV platforms and enrolled in the multicentre prospective OBSERVANT II study from December 2016 to September 2018 were compared according to the THV received. Outcomes were adjudicated through a linkage with administrative databases and adjusted by means of inverse propensity of treatment weighting (IPTW) based on propensity score. The primary end points were death from any cause and major adverse cardiac and cerebrovascular events (MACCE) at 5 years. Cumulative rates were reported consecutively for Evolut R/Pro, Sapien 3, Acurate Neo, and Portico groups. Results: A total of 2493 patients were considered. The median age was 83 years and median EuroSCORE 2 was 4.9%. After IPTW adjustment, the rates of all-cause death (53.6%, 46.7%, 50.5%, and 46.3%; P = 0.06) and MACCE (57.2%, 51.2%, 54.4%, and 50.6%; P = 0.08) did not differ among the groups at 5 years. The rate of rehospitalisation for heart failure (HF) (33.9%, 27.0%, 31.6%, 33.7%; P = 0.02) was significantly lower for Sapien 3 at 5 years. Conclusions: Data from real-world practice showed sustained and similar effectiveness of TAVR considering all the available THVs up to 5 years, but Sapien 3 showed a lower rate of rehospitalisation for HF
Impact of gender on 10-year outcome after coronary artery bypass grafting
OBJECTIVES
Our goal was to evaluate the impact of gender on the 10-year outcome of patients after isolated coronary artery bypass grafting (CABG) included in the Italian nationwide PRedictIng long-term Outcomes afteR Isolated coronary arTery bypass surgery (PRIORITY) study.
METHODS
The PRIORITY project was designed to evaluate the long-term outcomes of patients who underwent CABG and were included in 2 prospective multicentre cohort studies. The primary end point of this analysis was major adverse cardiac and cerebrovascular events. Baseline differences between the study groups were balanced with propensity score matching and inverse probability of treatment. Time to events was analysed using Cox regression and competing risk analysis.
RESULTS
The study population comprised 10 989 patients who underwent isolated CABG (women 19.6%). Propensity score matching produced 1898 well-balanced pairs. The hazard of major adverse cardiac and cerebrovascular event was higher in women compared to men [adjusted hazard ratio (HR) 1.13, 95% confidence interval (CI) 1.03–1.23; P = 0.009]. The incidence of major adverse cardiac and cerebrovascular event in women was significantly higher at 1 year (HR 1.31, 95% CI 1.11–1.55; P < 0.001) and after 1 year (HR 1.11, 95% CI 1.00–1.24; P = 0.05). Mortality at 10 years in the matched groups was comparable (HR 1.04, 95% CI 0.93–1.16; P = 0.531). Women have significantly a higher 10-year risk of myocardial infarction (adjusted HR 1.40, 95% CI 1.17–1.68; P = 0.002) and percutaneous coronary intervention (adjusted HR 1.32, 95% CI 1.10–1.59; P = 0.003).
CONCLUSIONS
The present study documented an excess of non-fatal cardiac events after CABG among women despite comparable 10-year survival with men. These findings suggest that studies investigating measures of tertiary prevention are needed to decrease the risk of adverse cardiovascular events among women
Bilateral Internal Thoracic Arteries Improve 10-Year Outcomes of Coronary Artery Bypass Grafting
BACKGROUND This observational cohort study was designed by the PRIORITY (PRedictIng long-term Outcomes afteR Isolated coronary arTery bypass surgery) steering committee to evaluate the 10-year follow-up outcome of bilateral internal thoracic arteries (BITA) versus single internal thoracic artery. METHODS The PRIORITY project was designed to evaluate long-term outcome of 2 large prospective multicenter cohort studies of coronary artery bypass grafting. Clinical data on isolated coronary artery bypass grafting were merged with administrative data to collect follow-up information. The primary endpoint was the composite outcome of major adverse cardiac and cerebrovascular events at 10-year follow-up. Secondary endpoints were individual components of major adverse cardiac and cerebrovascular events at 10 years and surgical site complications or infections. A pro-pensity score-based inverse probability treatment weighting (IPTW) was used to overcome the selection bias related to the observational nature of the study. RESULTS The study population consisted of 10,988 patients who underwent isolated coronary artery bypass grafting. BITA was used in 23.5%. The use of BITA is related to lower incidence of major adverse cardiac and cerebrovascular events at 10 years (adjusted hazard ratio [HR] 0.88, 95% CI 0.79-0.98, P < .001). BITA correlated with better 10-year survival (IPTW adjusted HR 0.87, 95% CI 0.78-1.00, P = .05), re-revascularization (IPTW adjusted HR 0.83, 95% CI 0.74-0.92, P < .001), and myocardial infarction (IPTW adjusted HR 0.86, 95% CI 0.77-0.95, P = .005) but to increased incidence of surgical site complications or infections (HR 2.12, 95% CI 1.39-3.24, P < .001). CONCLUSIONS In propensity-matched patients, use of BITA was associated with improved 10-year survival, freedom from repeat revascularization, and myocardial infarction but also higher incidence of surgical site complications. & COPY; 2023 by The Society of Thoracic Surgeons. Published by Elsevier Inc
Real-World Multiple Comparison of Transcatheter Aortic Valves: Insights From the Multicenter OBSERVANT II Study
Background:Head-to-head comparisons of devices for transcatheter aortic valve implantation (TAVI) are mostly limited to 2-arm studies so far. The aim of this study was to compare simultaneously outcomes of the most used, second- and third-generation transcatheter aortic valves in a real-world population. Methods:A total of 2728 patients undergoing TAVI with different second- and third-generation devices, and enrolled in the multicenter, prospective OBSERVANT II study (Observational Study of Effectiveness of TAVI With New Generation Devices for Severe Aortic Stenosis Treatment) from December 2016 to September 2018 were compared according to the transcatheter aortic valve received. Outcomes were adjudicated through a linkage with administrative databases, and adjusted using inverse propensity of treatment weighting. The primary end point was the composite of all-cause death, stroke and rehospitalization for heart failure at 1-year. Rates were reported consecutively for Evolut R, Evolut PRO, SAPIEN 3, ACURATE neo, and Portico groups. Results:The primary end point did not differ among groups (23.9% versus 24.7% versus 21.5% versus 23.7% versus 27.4%, respectively, P=0.56). Permanent pacemaker implantation was significantly lower for patients receiving SAPIEN 3 (19.9% versus 19.3% versus 12.5% versus 14.7% versus 22.1%, respectively, P<0.01) at 1 year. The SAPIEN 3 had lower rates of paravalvular regurgitation (moderate-to-severe grade 10.1% versus 5.0% versus 2.1% versus 13.1% versus 10.8%, respectively, P<0.01) but higher transprosthetic gradients (median mean gradients 7.0 versus 6.0 versus 10.0 versus 7.0 versus 8.0 mm Hg, respectively, P<0.01) after TAVI. Conclusions:Data from real-world practice showed low and comparable rates of complications after TAVI considering all the available devices. Patients receiving SAPIEN 3 valve had lower rates of paravalvular regurgitation and permanent pacemaker implantation, but higher transprosthetic gradients
Variations on the Author
“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
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