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For many decades, Europe has been a leader in neutron and muon science, establishing one of the most productive and well-developed research communities in the world. Much of the strength of the Eur...

Aims Randomised trials have demonstrated improvement in clinical outcomes with intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) compared with angiography-guided PCI. The ILUMIEN III trial demonstrated non-inferiority of an optical coherence tomography (OCT)- versus IVUS-guided PCI strategy in achieving similar post-PCI lumen dimensions. ILUMIEN IV is a large-scale, multicentre, randomised trial designed to demonstrate the superiority of OCT- versus angiography-guided stent implantation in patients with high-risk clinical characteristics (diabetes) and/or complex angiographic lesions in achieving larger post-PCI lumen dimensions and improving clinical outcomes. Methods and results ILUMIEN IV is a prospective, single-blind clinical investigation that will randomise between 2,490 and 3,656 patients using an adaptive design to OCT-guided versus angiography-guided coronary stent implantation in a 1:1 ratio. The primary endpoints are: (1) post-PCI minimal stent area assessed by OCT in each randomised arm, and (2) target vessel failure, the composite of cardiac death, target vessel myocardial infarction, or ischaemia-driven target vessel revascularisation. Clinical follow-up will continue for up to two years. The trial is currently enrolling, and the principal results are expected in 2022. Conclusions The large-scale ILUMIEN IV randomised controlled trial will evaluate the effectiveness of OCT-guided versus angiography-guided PCI in improving post-PCI lumen dimensions and clinical outcomes in patients with diabetes and/or with complex coronary lesions. Trial registration NCT03507777.

Background Limited study has detailed the late-term safety and efficacy of chronic total coronary occlusion (CTO) revascularization among multiple centers applying modern techniques and with newer-generation drug-eluting stents. Methods Among 20 centers, 222 patients enrolled in the XIENCE coronary stent, performance, and technique (EXPERT) CTO trial underwent CTO percutaneous coronary intervention (PCI) with everolimus-eluting stents (EES). Through planned 4-year follow-up, the primary composite endpoint of major adverse cardiac events (MACE; death, myocardial infarction [MI] and target lesion revascularization) and rates of individual component endpoints and stent thrombosis were determined. Results Demographic, lesion, and procedural characteristics included prior bypass surgery, 9.9%; diabetes, 40.1%; lesion length, 36.1 ± 18.5 mm; and stent length, 51.7 ± 27.2 mm. By 4 years, MACE rates were 31.6 and 22.4% by the pre-specified ARC and per-protocol definitions, respectively. Clinically-indicated target lesion revascularization at 4 years was 11.3%. In landmark analyses of events beyond the first year of revascularization, the annualized rates of target vessel-related MI and clinically-indicated target lesion revascularization were 0.53 and 1.3%, respectively. Through 4 years, the cumulative definite/probable stent thrombosis rate was 1.7% with no events occurring beyond the initial year of index revascularization. Conclusions In a multicenter registration trial representing contemporary technique and EES, these results demonstrate sustained long-term safety and effectiveness of EES in CTO percutaneous revascularization and can be used to inform shared decision making with patients being considered for CTO PCI relative to late safety and vessel patency.

Background The Absorb everolimus-eluting poly-L-lactic acid–based bioresorbable vascular scaffold (BVS) provides early drug delivery and mechanical support functions similar to metallic drug-eluting stents (DES), followed by complete bioresorption in approximately 3 years with recovery of vascular structure and function. The ABSORB III trial demonstrated noninferior rates of target lesion failure (cardiac death, target vessel myocardial infarction [TVMI], or ischemia-driven target lesion revascularization) at 1 year in 2,008 patients with coronary artery disease randomized to BVS versus cobalt-chromium everolimus-eluting stents (EES). Objectives This study sought to assess clinical outcomes through 3 years following BVS implantation. Methods Clinical outcomes from the ABSORB III trial were analyzed by randomized treatment assignment cumulative through 3 years, and between 1 and 3 years. Results The primary composite endpoint of target lesion failure through 3 years occurred in 13.4% of BVS patients and 10.4% of EES patients (p = 0.06), and between 1 and 3 years in 7.0% versus 6.0% of patients, respectively (p = 0.39). TVMI through 3 years was increased with BVS (8.6% vs. 5.9%; p = 0.03), as was device thrombosis (2.3% vs. 0.7%; p = 0.01). In BVS-assigned patients, treatment of very small vessels (those with quantitatively determined reference vessel diameter Conclusions In the ABSORB III trial, 3-year adverse event rates were higher with BVS than EES, particularly TVMI and device thrombosis. Longer-term clinical follow-up is required to determine whether bioresorption of the polymeric scaffold will influence patient prognosis. (ABSORB III Randomized Controlled Trial [RCT] [ABSORB-III]; NCT01751906)

Limited study has detailed the late-term safety and efficacy of chronic total coronary occlusion (CTO) revascularization among multiple centers applying modern techniques and with newer-generation drug-eluting stents.Among 20 centers, 222 patients enrolled in the XIENCE coronary stent, performance, and technique (EXPERT) CTO trial underwent CTO percutaneous coronary intervention (PCI) with everolimus-eluting stents (EES). Through planned 4-year follow-up, the primary composite endpoint of major adverse cardiac events (MACE; death, myocardial infarction [MI] and target lesion revascularization) and rates of individual component endpoints and stent thrombosis were determined.Demographic, lesion, and procedural characteristics included prior bypass surgery, 9.9%; diabetes, 40.1%; lesion length, 36.1 ± 18.5 mm; and stent length, 51.7 ± 27.2 mm. By 4 years, MACE rates were 31.6 and 22.4% by the pre-specified ARC and per-protocol definitions, respectively. Clinically-indicated target lesion revascularization at 4 years was 11.3%. In landmark analyses of events beyond the first year of revascularization, the annualized rates of target vessel-related MI and clinically-indicated target lesion revascularization were 0.53 and 1.3%, respectively. Through 4 years, the cumulative definite/probable stent thrombosis rate was 1.7% with no events occurring beyond the initial year of index revascularization.In a multicenter registration trial representing contemporary technique and EES, these results demonstrate sustained long-term safety and effectiveness of EES in CTO percutaneous revascularization and can be used to inform shared decision making with patients being considered for CTO PCI relative to late safety and vessel patency.

Objectives This is the first-in-human study of a drug-eluting bioresorbable vascular scaffold (BVS) for treatment of peripheral artery disease (PAD) involving the external iliac artery (EIA) and superficial femoral artery (SFA). Background Drug-eluting BVS has shown promise in coronary arteries. Methods The ESPRIT BVS system is a device-drug combination consisting of an everolimus-eluting poly-l-lactide scaffold. Safety and performance were evaluated in 35 subjects with symptomatic claudication. Results Lesions were located in the SFA (88.6%) and EIA (11.4%). Mean lesion length was 35.7 ± 16.0 mm. The study device was successfully deployed in 100% of cases, without recoil. Procedure-related minor complications were observed in 3 patients (groin hematoma, dissection). Within 2 years there was 1 unrelated death, but no patients in this cohort had an amputation. At 1 and 2 years, the binary restenosis rates were 12.1% and 16.1%, respectively, and target lesion revascularization was performed in 3 of 34 patients (8.8%) and 4 of 32 patients (11.8%), respectively. The ankle brachial index 0.75 ± 0.14 improved from pre-procedure to 0.96 ± 0.16 at 2 years’ follow-up. At 2 years, 71.0% of the patients were Rutherford-Becker 0, and 93.5% achieved a maximum walking distance of 1,500 feet. Conclusions The safety of the ESPRIT BVS was demonstrated with no procedure or device-related deaths or amputations within 2 years. The low occurrence of revascularizations was consistent with duplex-ultrasonography showing sustained patency at 2-years. (A Clinical Evaluation of the Abbott Vascular ESPRIT BVS [Bioresorbable Vascular Scaffold] System [ESPRIT I]; NCT01468974)

BACKGROUND In patients with coronary artery disease who receive metallic drug-eluting coronary stents, adverse events such as late target-lesion failure may be related in part to the persistent presence of the metallic stent frame in the coronary-vessel wall. Bioresorbable vascular scaffolds have been developed to attempt to improve longterm outcomes. METHODS In this large, multicenter, randomized trial, 2008 patients with stable or unstable angina were randomly assigned in a 2:1 ratio to receive an everolimus-eluting bioresorbable vascular (Absorb) scaffold (1322 patients) or an everolimus-eluting cobalt–chromium (Xience) stent (686 patients). The primary end point, which was tested for both noninferiority (margin, 4.5 percentage points for the risk difference) and superiority, was target-lesion failure (cardiac death, target-vessel myocardial infarction, or ischemia-driven target-lesion revascularization) at 1 year. RESULTS Target-lesion failure at 1 year occurred in 7.8% of patients in the Absorb group and in 6.1% of patients in the Xience group (difference, 1.7 percentage points; 95% confidence interval, −0.5 to 3.9; P = 0.007 for noninferiority and P = 0.16 for superiority). There was no significant difference between the Absorb group and the Xience group in rates of cardiac death (0.6% and 0.1%, respectively; P = 0.29), targetvessel myocardial infarction (6.0% and 4.6%, respectively; P = 0.18), or ischemiadriven target-lesion revascularization (3.0% and 2.5%, respectively; P = 0.50). Device thrombosis within 1 year occurred in 1.5% of patients in the Absorb group and in 0.7% of patients in the Xience group (P = 0.13). CONCLUSIONS In this large-scale, randomized trial, treatment of noncomplex obstructive coronary artery disease with an everolimus-eluting bioresorbable vascular scaffold, as compared with an everolimus-eluting cobalt–chromium stent, was within the prespecified margin for noninferiority with respect to target-lesion failure at 1 year. (Funded by Abbott Vascular; ABSORB III ClinicalTrials.gov number, NCT01751906.)

The Absorb everolimus-eluting poly-L-lactic acid-based bioresorbable vascular scaffold (BVS) provides early drug delivery and mechanical support functions similar to metallic drug-eluting stents (DES), followed by complete bioresorption in approximately 3 years with recovery of vascular structure and function. The ABSORB III trial demonstrated noninferior rates of target lesion failure (cardiac death, target vessel myocardial infarction [TVMI], or ischemia-driven target lesion revascularization) at 1 year in 2,008 patients with coronary artery disease randomized to BVS versus cobalt-chromium everolimus-eluting stents (EES).This study sought to assess clinical outcomes through 3 years following BVS implantation.Clinical outcomes from the ABSORB III trial were analyzed by randomized treatment assignment cumulative through 3 years, and between 1 and 3 years.The primary composite endpoint of target lesion failure through 3 years occurred in 13.4% of BVS patients and 10.4% of EES patients (p = 0.06), and between 1 and 3 years in 7.0% versus 6.0% of patients, respectively (p = 0.39). TVMI through 3 years was increased with BVS (8.6% vs. 5.9%; p = 0.03), as was device thrombosis (2.3% vs. 0.7%; p = 0.01). In BVS-assigned patients, treatment of very small vessels (those with quantitatively determined reference vessel diameter 2.25 mm) was an independent predictor of 3-year TLF and scaffold thrombosis.In the ABSORB III trial, 3-year adverse event rates were higher with BVS than EES, particularly TVMI and device thrombosis. Longer-term clinical follow-up is required to determine whether bioresorption of the polymeric scaffold will influence patient prognosis. (ABSORB III Randomized Controlled Trial [RCT] [ABSORB-III]; NCT01751906).

This is the first-in-human study of a drug-eluting bioresorbable vascular scaffold (BVS) for treatment of peripheral artery disease (PAD) involving the external iliac artery (EIA) and superficial femoral artery (SFA).Drug-eluting BVS has shown promise in coronary arteries.The ESPRIT BVS system is a device-drug combination consisting of an everolimus-eluting poly-l-lactide scaffold. Safety and performance were evaluated in 35 subjects with symptomatic claudication.Lesions were located in the SFA (88.6%) and EIA (11.4%). Mean lesion length was 35.7 ± 16.0 mm. The study device was successfully deployed in 100% of cases, without recoil. Procedure-related minor complications were observed in 3 patients (groin hematoma, dissection). Within 2 years there was 1 unrelated death, but no patients in this cohort had an amputation. At 1 and 2 years, the binary restenosis rates were 12.1% and 16.1%, respectively, and target lesion revascularization was performed in 3 of 34 patients (8.8%) and 4 of 32 patients (11.8%), respectively. The ankle brachial index 0.75 ± 0.14 improved from pre-procedure to 0.96 ± 0.16 at 2 years' follow-up. At 2 years, 71.0% of the patients were Rutherford-Becker 0, and 93.5% achieved a maximum walking distance of 1,500 feet.The safety of the ESPRIT BVS was demonstrated with no procedure or device-related deaths or amputations within 2 years. The low occurrence of revascularizations was consistent with duplex-ultrasonography showing sustained patency at 2-years. (A Clinical Evaluation of the Abbott Vascular ESPRIT BVS [Bioresorbable Vascular Scaffold] System [ESPRIT I]; NCT01468974).

Udgivelsesdato: 2008-Mar-15 BACKGROUND: A fully bioabsorbable drug-eluting coronary stent that scaffolds the vessel wall when needed and then disappears once the acute recoil and constrictive remodelling processes have subsided has theoretical advantages. The bioasorbable everolimus-eluting stent (BVS) has a backbone of poly-L-lactic acid that provides the support and a coating of poly-D,L-lactic acid that contains and controls the release of the antiproliferative agent everolimus. We assessed the feasibility and safety of this BVS stent. METHODS: In this prospective, open-label study we enrolled 30 patients who had either stable, unstable, or silent ischaemia and a single de-novo lesion that was suitable for treatment with a single 3.0 x 12 mm or 3.0 x 18 mm stent. Patients were enrolled from four academic hospitals in Auckland, Rotterdam, Krakow, and Skejby. The composite endpoint was cardiac death, myocardial infarction, and ischaemia-driven target lesion revascularisation. Angiographic endpoints were available for 26 patients and intravascular-ultrasound endpoints for 24 patients. Clinical endpoints were assessed in all 30 patients at 6 and 12 months. In a subset of 13 patients, optical coherence tomography was undertaken at baseline and follow-up. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00300131. FINDINGS: Procedural success was 100% (30/30 patients), and device success 94% (29/31 attempts at implantation of the stent). At 1 year, the rate of major adverse cardiac events was 3.3%, with only one patient having a non-Q wave myocardial infarction and no target lesion revascularisations. No late stent thromboses were recorded. At 6-month follow-up, the angiographic in-stent late loss was 0.44 (0.35) mm and was mainly due to a mild reduction of the stent area (-11.8%) as measured by intravascular ultrasound. The neointimal area was small (0.30 [SD 0.44] mm2), with a minimal area obstruction of 5.5%. INTERPRETATION: This study shows the feasibility of implantation of the bioabsorbable everolimus-eluting stent, with an acceptable in-stent late loss, minimal intrastent neointimal hyperplasia, and a low stent area obstruction. FUNDING: Abbott Vascular.

The Absorb bioresorbable scaffold (BVS) provides comparable 12-month clinical outcomes to Xience everolimus-eluting stents in appropriately sized vessels. Differences in device structure (strut thickness and width) and resorption might impact outcomes in the setting of bailout (unplanned) device

Extended X-ray absorption fine structure (EXAFS) and neutron scattering data from monoclinic zirconia are analysed independently and simultaneously by reverse Monte Carlo (RMC) modelling. X-ray and neutron powder diffraction data are analysed by Rietveld refinement. The results are compared with respect to the local structure around the zirconium cations. Monoclinic zirconia was chosen as a model system for the comparison of structural information obtained by EXAFS spectroscopy and scattering methods because it is crystalline but also has some local disorder. In the case of zirconia, analysis of EXAFS spectra by RMC modelling results in reliable and accurate information on the local structure, consistent with neutron scattering and diffraction experiments.

For the last five years, collaboration between European neutron and muon facilities has been centred around the NMI3 project – the Integrated Infrastructure Initiative (I3) for Neutron Scattering and Muon Spectroscopy. This project has recently finished, so it is timely to look back at NMI3’s successes (many) and its failures (few).

The Studsvik Neutron Research Laboratory (Neutronforsknings-laboratoriet—NFL), which is administered by the University of Uppsala, is the center for reactor based research in physics, chemistry, biology and materials science for scientists at Swedish universities and other institutions. Within the past two years the facilities have also been made available to scientists from other countries. There are approximately 30 permanent staff members at NFL, and in addition, ten researchers and thesis students spend a significant amount of time there. Between 30 percent and 70 percent of the time on all the instruments is allocated by the Research Board which meets twice a year to consider proposals. The remainder of the time is allocated at the discretion of senior scientists. Research proposals can be submitted at any time, though the formal dates for proposals to be considered by the Research Board are April 15th and October 15th. Reports on the experiments that have been performed, and on other work a...

Neutron Imaging and Applications offers an introduction to the basics of neutron beam production and instrumentation in addition to the wide scope of techniques that provide unique imaging capabilities over a broad and diverse range of applications. An instructional overview of neutron sources, optics and detectors, allows readers to delve more deeply into the discussions of radiography, tomography, phase contrast imaging and prospective applications using advanced neutron holography techniques and polarized beams. A section devoted to overviews in a growing range of applications describes imaging of fuel cells and hydrogen storage devices for a robust hydrogen economy; new directions in material science and engineering; the investigation of precious artifacts of cultural heritage importance; determination of plant physiology and growth processes; imaging of biological tissues and macromolecules, and the practical elements of neutron imaging for homeland security and contraband detection. Written by key experts in the field, researchers and engineers involved with imaging technologies will find Neutron Imaging and Applications a valuable reference.

On three continents major new neutron scattering facilities are under construction that will provide unprecedented opportunities for scientific discovery. The Spallation Neutron Source (SNS) under construction at Oak Ridge National Laboratory (ORNL) will become operational in 2006, the Japanese Spallation Source is planned for completion in 2007, and the second target station at ISIS is due to come on-line in 2008. All three will be equipped with state-of-the-art instrumentation, large detector arrays and, with the associated increases in flux, will deliver orders of magnitude increases in data volume. Current data visualization and analysis software will be seriously challenged to keep pace with these changes.