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Diagnostic performance of stress myocardial perfusion imaging for coronary artery disease: a systematic review and meta-analysis
Objectives: To determine and compare the diagnostic performance of stress myocardial perfusion imaging (MPI) for the diagnosis of obstructive coronary artery disease (CAD), using conventional coronary angiography (CCA) as the reference standard. Methods: We searched Medline and Embase for literature that evaluated stress MPI for the diagnosis of obstructive CAD using magnetic resonance imaging (MRI), contrast-enhanced echocardiography (ECHO), single-photon emission computed tomography (SPECT) and positron emission tomography (PET). Results: All pooled analyses were based on random effects models. Articles on MRI yielded a total of 2,970 patients from 28 studies, articles on ECHO yielded a sample size of 795 from 10 studies, articles on SPECT yielded 1,323 from 13 studies. For CAD defined as either at least 50 %, at least 70 % or at least 75 % lumen diameter reduction on CCA, the natural logarithms of the diagnostic odds ratio (lnDOR) for MRI (3.63; 95 % CI 3.26–4.00) was significantly higher compared to that of SPECT (2.76; 95 % CI 2.28–3.25; P = 0.006) and that of ECHO (2.83; 95 % CI 2.29–3.37; P = 0.02). There was no significant difference between the lnDOR of SPECT and ECHO (P = 0.52). Conclusion: Our results suggest that MRI is superior for the diagnosis of obstructive CAD compared with ECHO and SPECT. ECHO and SPECT demonstrated similar diagnostic performance
Pre-hospital management, procedural performance and outcomes for primary percutaneous coronary intervention in st-elevation myocardial infarction in the netherlands: Insights from the dutch cohort of the apposition-III trial
Aim The aim of this study was to achieve useful insights into pre-hospital management and procedural performance for ST-elevation myocardial infarction (STEMI) in the Netherlands by extrapolating patient characteristics, and procedural and clinical outcomes of the Dutch patient cohort from the APPOSITION-III trial. Methods This is a retrospective analysis from the APPOSITION-III trial with respect to the geographical borders of STEMI management. The APPOSITION-III trial was a European registry for the use of the STENTYS self-expandable stent in STEMI patients undergoing primary percutaneous coronary intervention (PPCI). 965 Patients were enrolled mainly in the Netherlands (n = 420, 43.5 % of the overall study population), Germany (n = 165) and France (n = 131). The data from the Dutch cohort were compared with both the overall study population, and the French and German cohorts, respectively, as well as the European Society of Cardiology (ESC) STEMI guidelines. Results In this trial there was a wide inter-country variation on symptom-to-balloon time, 165 minutes (120–318) in the Netherlands, 270 minutes (180–650) in Germany and 360 minutes (120–480) in France, respectively. In general, a preload of dual antiplatelet therapy (DAPT) combined with heparin was more often performed in the Dutch and French cohort than in the German cohort. DAPT at discharge was high across the whole APPOSITION-III population. No important differences were seen between the different groups according to the endpoints major adverse cardiac event and stent thrombosis. Conclusion In the Dutch cohort of an European multicentre STEMI study (APPOSITION-III trial), the performance in terms of symptom-to-balloon time, and pre-, peri- and post-procedural medical treatment is in line with the recommendations of ESC STEMI guidelines
Understanding SDBD Actuators: An Experimental Study on Plasma Characteristics
The working mechanisms of surface dielectric barrier discharge (SDBD) plasma actuators foreseen as aerodynamic control devices is investigated experimentally on a common platform, referred to as the NATO-AVT-RTO-190 test case. A better understanding of the working principle and characteristics of SDBD paves the way for more efficient and safe use of plasma actuators in aerodynamic applications. In this study, a characterisation of the plasma is done by current measurements, fast-camera plasma imaging and force measurements. Furthermore, more advanced plasma characteristics such as reduced electric field and excited species population are found by Optical Emission Spectroscopy. The collective goal of this research is to contribute to a database which can also be used for numerical verification and validation by varying the key parameters such as frequency and voltage
OCT assessment of the long-term vascular healing response 5 years after everolimus-eluting bioresorbable vascular scaffold
AbstractBackgroundAlthough recent observations suggest a favorable initial healing process of the everolimus-eluting bioresorbable vascular scaffold (BVS), little is known regarding long-term healing response.ObjectivesThis study assessed the in vivo vascular healing response using optical coherence tomography (OCT) 5 years after elective first-in-man BVS implantation.MethodsOf the 14 living patients enrolled in the Thoraxcenter Rotterdam cohort of the ABSORB A study, 8 patients underwent invasive follow-up, including OCT, 5 years after implantation. Advanced OCT image analysis included luminal morphometry, assessment of the adluminal signal-rich layer separating the lumen from other plaque components, visual and quantitative tissue characterization, and assessment of side-branch ostia “jailed” at baseline.ResultsIn all patients, BVS struts were integrated in the vessel and were not discernible. Both minimum and mean luminal area increased from 2 to 5 years, whereas lumen eccentricity decreased over time. In most patients, plaques were covered by a signal-rich, low-attenuating layer. Minimum cap thickness over necrotic core was 155 ± 90 μm. One patient showed plaque progression and discontinuity of this layer. Side-branch ostia were preserved with tissue bridge thinning that had developed in the place of side-branch struts, creating a neo-carina.ConclusionsAt long-term BVS follow-up, we observed a favorable tissue response, with late luminal enlargement, side-branch patency, and development of a signal-rich, low-attenuating tissue layer that covered thrombogenic plaque components. The small size of the study and the observation of a different tissue response in 1 patient warrant judicious interpretation of our results and confirmation in larger studies
A dual propagation contours technique for semi-automated assessment of systolic and diastolic cardiac function by CMR
<p>Abstract</p> <p>Background</p> <p>Although cardiovascular magnetic resonance (CMR) is frequently performed to measure accurate LV volumes and ejection fractions, LV volume-time curves (VTC) derived ejection and filling rates are not routinely calculated due to lack of robust LV segmentation techniques. VTC derived peak filling rates can be used to accurately assess LV diastolic function, an important clinical parameter. We developed a novel geometry-independent dual-contour propagation technique, making use of LV endocardial contours manually drawn at end systole and end diastole, to compute VTC and measured LV ejection and filling rates in hypertensive patients and normal volunteers.</p> <p>Methods</p> <p>39 normal volunteers and 49 hypertensive patients underwent CMR. LV contours were manually drawn on all time frames in 18 normal volunteers. The dual-contour propagation algorithm was used to propagate contours throughout the cardiac cycle. The results were compared to those obtained with single-contour propagation (using either end-diastolic or end-systolic contours) and commercially available software. We then used the dual-contour propagation technique to measure peak ejection rate (PER) and peak early diastolic and late diastolic filling rates (ePFR and aPFR) in all normal volunteers and hypertensive patients.</p> <p>Results</p> <p>Compared to single-contour propagation methods and the commercial method, VTC by dual-contour propagation showed significantly better agreement with manually-derived VTC. Ejection and filling rates by dual-contour propagation agreed with manual (dual-contour – manual PER: -0.12 ± 0.08; ePFR: -0.07 ± 0.07; aPFR: 0.06 ± 0.03 EDV/s, all P = NS). However, the time for the manual method was ~4 hours per study versus ~7 minutes for dual-contour propagation. LV systolic function measured by LVEF and PER did not differ between normal volunteers and hypertensive patients. However, ePFR was lower in hypertensive patients vs. normal volunteers, while aPFR was higher, indicative of altered diastolic filling rates in hypertensive patients.</p> <p>Conclusion</p> <p>Dual-propagated contours can accurately measure both systolic and diastolic volumetric indices that can be applied in a routine clinical CMR environment. With dual-contour propagation, the user interaction that is routinely performed to measure LVEF is leveraged to obtain additional clinically relevant parameters.</p
Rationale and design of a prospective substudy of clinical endpoint adjudication processes within an investigator-reported randomised controlled trial in patients with coronary artery disease: the GLOBAL LEADERS Adjudication Sub-StudY (GLASSY)
pragmatic and superiority randomised controlled trial
designed to challenge the current treatment paradigm of dual
antiplatelet therapy (DAPT) for 12 months followed by aspirin
monotherapy among patients undergoing percutaneous
coronary intervention. By design, all study endpoints are
investigator reported (IR) and not subject to formal adjudication
by an independent Clinical Event Committee (CEC), which may
introduce detection, reporting or ascertainment bias.
Methods and analysis We designed the GLOBAL LEADERS
Adjudication Sub-StudY (GLASSY) to prospectively implement,
in a large sample of patients enrolled within the GLOBAL
LEADERS trial (7585 of 15 991, 47.5%), an independent
adjudication process of reported and unreported potential
endpoints, using standardised CEC procedures, in order
to assess whether 23-month ticagrelor monotherapy
(90mg twice daily) after 1-month DAPT is non-inferior to a
standard regimen of DAPT for 12 months followed by aspirin
monotherapy for the primary efficacy endpoint of death, nonfatal myocardial infarction, non-fatal stroke or urgent target
vessel revascularisation and superior for the primary safety
endpoint of type 3 or 5 bleeding according to the Bleeding
Academic Research Consortium criteria. This study will
comprehensively assess the comparative safety and efficacy
of the two tested antithrombotic strategies on CEC-adjudicated
ischaemic and bleeding endpoints and will provide insights
into the role of a standardised CEC adjudication process on
the interpretation of study findings by quantifying the level
of concordance between IR-reported and CEC-adjudicated
events.
Ethics and dissemination GLASSY has been approved
by local ethics committee of all study sites and/or by the
central ethics committee for the country depending on
country-specific regulations. In all cases, they deemed that
it was not neces
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