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In this article, we analyse the impact of academic mobility on the construction of knowledge for Chilean scholars who have studied abroad. We conducted 41 semi-structured interviews with Chilean-born scholars in the social sciences and humanities, who accepted jobs at national research universities in Chile after receiving their doctorates abroad. Findings show that international academic mobility allowed these participants to question legitimised ways of doing knowledge, where they can stretch the academic harness that increasingly rules their knowledge construction. Our main argument is that knowledge construction process is neither linear nor unidimensional and it occurs as a rhizomatic process in a multidimensional space.

In patients undergoing percutaneous coronary intervention (PCI) in the work-up pre–transcatheter aortic valve replacement (TAVR), the incidence and clinical impact of late bleeding events (LBEs) remain largely unknown. This study sought to determine the incidence, clinical characteristics, associated factors, and outcomes of LBEs in patients undergoing PCI in the work-up pre-TAVR. This was a multicenter study including 1,457 consecutive patients (mean age 81 ± 7 years; 41.5% women) who underwent TAVR and survived beyond 30 days. LBEs (>30 days post-TAVR) were defined according to the Valve Academic Research Consortium-2 criteria. LBEs occurred in 116 (7.9%) patients after a median follow-up of 23 (IQR: 12-40) months. Late bleeding was minor, major, and life-threatening or disabling in 21 (18.1%), 63 (54.3%), and 32 (27.6%) patients, respectively. Periprocedural (<30 days post-TAVR) major bleeding and the combination of antiplatelet and anticoagulation therapy at discharge were independent factors associated with LBEs (P ≤ 0.02 for all). LBEs conveyed an increased mortality risk at 4-year follow-up compared with no bleeding (43.9% vs 36.0; P = 0.034). Also, LBE was identified as an independent predictor of all-cause mortality after TAVR (HR: 1.39; 95% CI: 1.05-1.83; P = 0.020). In TAVR candidates with concomitant significant coronary artery disease requiring percutaneous treatment, LBEs after TAVR were frequent and associated with increased mortality. Combining antiplatelet and anticoagulation regimens and the occurrence of periprocedural bleeding determined an increased risk of LBEs. Preventive strategies should be pursued for preventing late bleeding after TAVR, and further studies are needed to provide more solid evidence on the most safe and effective antithrombotic regimen post-TAVR in this challenging group of patients. [Display omitted] [ABSTRACT FROM AUTHOR]

The burden of cardiac death after transcatheter aortic valve replacement (TAVR), particularly from advanced heart failure (HF) and sudden cardiac death (SCD), remains largely unknown. This study sought to evaluate the incidence and predictors of SCD and HF-related death in TAVR recipients treated with newer-generation devices. This study included a total of 5,421 consecutive patients who underwent TAVR with newer-generation devices using balloon (75.7%) or self-expandable (24.3%) valves. After a median follow-up of 2 (IQR: 1-3) years, 976 (18.0%) patients had died, 50.8% from cardiovascular causes. Advanced HF and SCD accounted for 11.6% and 7.5% of deaths, respectively. Independent predictors of HF-related death were atrial fibrillation (HR: 2.17; 95% CI: 1.47-3.22; P < 0.001), prior pacemaker (HR: 1.79; 95% CI: 1.10-2.92; P = 0.01), reduced left ventricular ejection fraction (HR: 1.08 per 5% decrease; 95% CI: 1.01-1.14; P = 0.02), transthoracic approach (HR: 2.50; 95% CI: 1.37-4.55; P = 0.003), and new-onset persistent left bundle branch block (HR: 1.85; 95% CI: 1.14-3.02; P = 0.01). Two baseline characteristics (diabetes, HR: 1.81; 95% CI: 1.13-2.89; P = 0.01; and chronic kidney disease, HR: 1.72; 95% CI: 1.02-2.90; P = 0.04) and 3 procedural findings (valve in valve, HR: 2.17; 95% CI: 1.01-4.64; P = 0.04; transarterial nontransfemoral approach, HR: 2.23; 95% CI: 1.23-4.48; P = 0.01; and periprocedural ventricular arrhythmia, HR: 7.19; 95% CI: 2.61-19.76; P < 0.001) were associated with an increased risk of SCD after TAVR. Advanced HF and SCD accounted for a fifth of deaths after TAVR in contemporary practice. Potentially treatable factors leading to increased risk of HF deaths and SCD were identified, such as arrhythmia/dyssynchrony factors for HF and valve-in-valve TAVR or periprocedural ventricular arrhythmias for SCD. [Display omitted] [ABSTRACT FROM AUTHOR]

The aim of this study was to compare, in a cohort of patients with complex coronary artery disease (CAD) and severe aortic stenosis (AS), the clinical outcomes associated with transfemoral transcatheter aortic valve replacement (TAVR) (plus percutaneous coronary intervention [PCI]) versus surgical aortic valve replacement (SAVR) (plus coronary artery bypass grafting [CABG]). Patients with complex CAD were excluded from the main randomized trials comparing TAVR with SAVR, and no data exist comparing TAVR + PCI vs SAVR + CABG in such patients. A multicenter study was conducted including consecutive patients with severe AS and complex CAD (SYNTAX [Synergy Between PCI with Taxus and Cardiac Surgery] score >22 or unprotected left main disease). A 1:1 propensity-matched analysis was performed to account for unbalanced covariates. The rates of major adverse cardiac and cerebrovascular events (MACCE), including all-cause mortality, nonprocedural myocardial infarction, need for new coronary revascularization, and stroke, were evaluated. A total of 800 patients (598 undergoing SAVR + CABG and 202 undergoing transfemoral TAVR + PCI) were included, and after propensity matching, a total of 156 pairs of patients were generated. After a median follow-up period of 3 years (interquartile range: 1-6 years), there were no significant differences between groups for MACCE (HR for transfemoral TAVR vs SAVR: 1.33; 95% CI: 0.89-1.98), all-cause mortality (HR: 1.25; 95% CI: 0.81-1.94), myocardial infarction (HR: 1.16; 95% CI: 0.41-3.27), and stroke (HR: 0.42; 95% CI: 0.13-1.32), but there was a higher rate of new coronary revascularization in the TAVR + PCI group (HR: 5.38; 95% CI: 1.73-16.7). In patients with severe AS and complex CAD, TAVR + PCI and SAVR + CABG were associated with similar rates of MACCE after a median follow-up period of 3 years, but TAVR + PCI recipients exhibited a higher risk for repeat coronary revascularization. Future trials are warranted. [Display omitted] [ABSTRACT FROM AUTHOR]

Transition metal oxide (TMOs) layers have interesting properties as selective contacts, i.e., hole or electron transport layers for novel semiconductor devices. Especially, oxides of molybdenum (MoO 3), vanadium (V 2 O 5), and tungsten (WO 3) show good bahaviour acting as front hole-selective contacts for n-type crystalline-silicon heterojunction solar cells. Laser scribing has been widely used for thin-film ablation and seems the appropriate technology for device manufacturing with such non-conventional materials. In this work, we study the laser scribing of non-stoichiometric evaporated WO x , VO x , and MoO x films with three different wavelengths (1064, 532, and 355 nm) with pulse duration in the nanosecond and picosecond regimes. The selection of the proper laser source allows a wide parametric window, with complete removal of the TMO films and no alteration of the silicon substrate. The results on the isolation of diodes and their electrical characteristics show the quality of the laser scribing processes. [ABSTRACT FROM AUTHOR]

This study sought to determine, in patients undergoing percutaneous coronary intervention (PCI) during the work-up pre–transcatheter aortic valve replacement (TAVR): 1) the clinical and peri-procedural PCI characteristics; 2) the long-term outcomes; and 3) the clinical events in those patients with complex coronary features. A PCI is performed in about 25% of TAVR candidates, but procedural features and late outcomes of pre-TAVR PCI remain largely unknown. Multicenter study including 1197 consecutive patients who had PCI in the work-up pre-TAVR. A total of 1,705 lesions (1.5 ± 0.7 lesions per patient) were included. Death, stroke, myocardial infarction, and major adverse cardiovascular and cerebrovascular events (MACCE) were recorded, as well as target lesion failure (TLF) and target vessel failure (TVF). One-half of patients exhibited a multivessel disease and the mean SYNTAX (SYNergy between PCI with TAXUS and Cardiac Surgery) score was 12.1 ± 9.1. The lesions were of B2/C type, calcified, bifurcation, and ostial in 49.9%, 45.8%, 21.4%, and 19.3% of cases, respectively. After a median follow-up of 2 (interquartile range: 1 to 3) years, a total of 444 (37.1%) patients presented an MACCE. Forty patients exhibited TVF (3.3%), with TLF identified in 32 (2.7%) patients. By multivariable analysis, previous peripheral artery disease (p < 0.001), chronic obstructive pulmonary disease (p = 0.002), atrial fibrillation (p = 0.003), diabetes mellitus (p = 0.012), and incomplete revascularization (p = 0.014) determined an increased risk of MACCE. In patients with unprotected left main or SYNTAX score >32 (n = 128), TLF, TVF, and MACCE rates were 3.9%, 6.3%, and 35.9%, respectively (p = 0.378; p = 0.065, and p = 0.847, respectively, vs. the rest of the population). Patients undergoing PCI in the work-up pre-TAVR frequently exhibited complex coronary lesions and multivessel disease. PCI was successful in most cases, and TLF and TVF rates at 2-year follow-up were low, also among patients with high-risk coronary features. However, overall MACCE occurred in about one-third of patients, with incomplete revascularization determining an increased risk. These results should inform future studies to better determine the optimal revascularization strategy pre-TAVR. [ABSTRACT FROM AUTHOR]

This study sought to determine the incidence, clinical characteristics, associated factors, and outcomes of late cerebrovascular events (LCVEs) (>30 days post-procedure) following transcatheter aortic valve replacement (TAVR). Scarce data exist on LCVEs following TAVR. This was a multicenter study including 3,750 consecutive patients (mean age, 80 ± 8 years; 50.5% of women) who underwent TAVR and survived beyond 30 days. LCVEs were defined according to the Valve Academic Research Consortium 2 (VARC 2) criteria. LCVEs occurred in 192 (5.1%) patients (stroke, 80.2%; transient ischemic attack, 19.8%) after a median follow-up of 2 (1 to 4) years. Late stroke was of ischemic, hemorrhagic, and undetermined origin in 80.5%, 18.8%, and 0.7% of patients, respectively. Older age, previous cerebrovascular disease, higher mean aortic gradient at baseline, the occurrence of stroke during the periprocedural TAVR period, and the lack of anticoagulation (novel oral anticoagulants or vitamin K antagonists) post-TAVR were independent factors associated with late ischemic stroke/transient ischemic attack (p < 0.05 for all). Echocardiographic data at the time of the LCVE showed no signs of valve thrombosis or degeneration in the vast majority (97%) patients. Late stroke was disabling in 107 (69.5%) patients (ischemic, 68%; hemorrhagic, 79%), and associated with an in-hospital mortality rate of 29.2%. LCVEs occurred in 5.1% of TAVR recipients after a median follow-up of 2 years. LCVEs were ischemic in most cases, with older age, previous cerebrovascular events, higher mean aortic gradient at baseline, the occurrence during the periprocedural TAVR period, and lack of anticoagulation (but not valve thrombosis/degeneration) determining an increased risk. Late stroke was disabling in most cases and associated with dreadful early and midterm outcomes. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the impact of new-onset persistent (NOP) left bundle branch block (LBBB) on long-term (>2 year) outcomes after transcatheter aortic valve replacement (TAVR). The impact of NOP-LBBB after TAVR remains controversial and no data exist regarding long-term outcomes. A total of 1,020 consecutive patients without pre-existing LBBB or permanent pacemaker implantation (PPI) undergoing TAVR were included. NOP-LBBB was defined as any new LBBB post-TAVR that persisted at hospital discharge. Follow-up clinical and echocardiographic data were obtained at a median of 3 years (interquartile range: 2 to 5 years) post-TAVR. NOP-LBBB occurred in 212 patients (20.1%) following TAVR. There were no differences between NOP-LBBB and no NOP-LBBB groups, except for a higher use of the self-expandable CoreValve system in the NOP-LBBB group (p < 0.001). At follow-up, there were no differences between NOP-LBBB and no NOP-LBBB groups in all-cause mortality (45.3% vs. 42.5%; adjusted hazard ratio [HR]:1.09; 95% confidence interval [CI]: 0.82 to 1.47; p = 0.54), cardiovascular mortality (14.2% vs. 14.4%; adjusted HR: 1.02; 95% CI: 0.56 to 1.87; p = 0.95), or heart failure rehospitalization (19.8% vs. 15.6%; adjusted HR: 1.44; 95% CI: 0.85 to 2.46; p = 0.18). NOP-LBBB was associated with an increased risk of permanent pacemaker implantation at follow-up (15.5% vs. 5.4%; adjusted HR: 2.45; 95% CI: 1.37 to 4.38; p = 0.002), with the highest risk within the first 12 months. Left ventricular ejection fraction increased over time in patients with no NOP-LBBB but slightly decreased in those with NOP-BBB (p < 0.001 for changes in left ventricular ejection fraction between groups). After a median follow-up of 3 years post-TAVR, NOP-LBBB was not associated with a higher mortality or heart failure rehospitalization. However, NOP-LBBB increased the risk of permanent pacemaker implantation and negatively impacted left ventricular function over time. These results should inform future efforts for improving the management of patients with NOP-LBBB post-TAVR. [ABSTRACT FROM AUTHOR]

Objectives The authors sought to determine: 1) the global arrhythmic burden; 2) the rate of arrhythmias leading to a treatment change; and 3) the incidence of high-degree atrioventricular block (HAVB) at 12-month follow-up in patients with new-onset persistent left bundle branch block (LBBB) following transcatheter aortic valve replacement (TAVR). Background Controversial data exist on the occurrence of significant arrhythmias in patients with LBBB post-TAVR. Methods This was a multicenter prospective study including 103 consecutive patients with new-onset persistent LBBB post-TAVR with the balloon-expandable SAPIEN XT/3 valve (n = 53), or the self-expanding CoreValve/Evolut R system (n = 50). An implantable cardiac monitor (Reveal XT, Reveal Linq) was implanted at 4 (3 to 6) days post-TAVR, and patients had continuous electrocardiogram monitoring for 12 months. All arrhythmic events were adjudicated in a central electrocardiography core lab. Primary endpoints were the incidence of arrhythmias leading to a treatment change, and the incidence of HAVB at 12-month follow-up. Results A total of 1,553 new arrhythmic events were detected in 44 patients (1,443 episodes of tachyarrhythmia in 26 patients [atrial fibrillation/flutter/atrial tachycardia: 1,427, ventricular tachycardia 16]; 110 episodes of bradyarrhythmia in 21 patients [HAVB 54, severe bradycardia 56]). All arrhythmic events were silent in 34 patients (77%), the arrhythmic event led to a treatment change in 19 patients (18%), and 11 patients (11%) required pacemaker or implantable cardioverter-defibrillator implantation (due to HAVB, severe bradycardia, or ventricular tachycardia episodes in 9, 1, and 1 patient, respectively). A total of 12 patients died at 1-year follow-up, 1 from sudden death. Conclusions A high incidence of arrhythmic events was observed at 1-year follow-up in close to one-half of the patients with LBBB post-TAVR. Significant bradyarrhythmias occurred in one-fifth of the patients, and PPM was required in nearly one-half of them. These data support the use of a cardiac monitoring device for close follow-up and expediting the initiation of treatment in this challenging group of patients. (Ambulatory Electrocardiographic Monitoring for the Detection of High-Degree Atrio-Ventricular Block in Patients With New-onset PeRsistent LEft Bundle Branch Block After Transcatheter Aortic Valve Implantation [MARE study]: NCT02153307 ) [ABSTRACT FROM AUTHOR]

Background: The potential benefit of using larger or smaller transcatheter heart valves (THV) in patients with borderline aortic annulus measurement (BAM) remains uncertain. The objective of this study was to evaluate the clinical outcomes associated with the selection of larger or smaller THV in the context of BAM. Methods: This was a multicenter observational study including patients who underwent transcatheter aortic valve replacement with the SAPIEN 3 or SAPIEN 3 Ultra-valve systems (Edwards Lifesciences, Irvine, CA) from April 2014 to June 2021. BAM was defined according to the manufacturer sizing chart and included the following annulus areas: 314 to 346, 400 to 430, 500 to 546 mm2. A 1:1 propensity score matching was used to compare outcomes of patients with larger or smaller THV. Results: From a total of 2467 patients, BAM was identified in 852 patients (34.5%). A larger and smaller THV was selected in 338 (39.7%) and 514 patients (60.3%) patients, respectively. The choice of a larger THV was associated (before and after propensity matching) with a higher risk of new-onset left bundle branch block (HR, 2.25 [95% CI, 1.39–3.65; P =0.001) and permanent pacemaker implantation (HR, 1.86 [95% CI, 1.11–3.09]; P =0.016) without any impact on gradients or the risk of moderate or severe paravalvular regurgitation at discharge (HR, 0.78 [95% CI, 0.41–1.45]; P =0.427). The risk of periprocedural complications such as aortic rupture and tamponade was low (<1%) and similar between groups. Conclusions: In patient with BAM, selecting a larger SAPIEN 3/Ultra THV increased the risk of conduction disturbances without any benefit on valve hemodynamics and clinical outcomes. [ABSTRACT FROM AUTHOR]