10 research outputs found
Tissue injury characterization by pre-contrast T1 mapping post myocardial infarction
Shah M Azarisman, Andrew Li, Dennis T Wong, James D Richardson, Seng Keong Chua, Luay Samaraie, Samuel L Sidharta, Timothy Glenie, Kerry Williams, Ben Koschade, Karen Teo, Matthew Worthley, Stephen G Worthle
High-sensitivity troponin assays for the early rule-out or diagnosis of acute myocardial infarction in people with acute chest pain: a systematic review and cost-effectiveness analysis.
BACKGROUND: Early diagnosis of acute myocardial infarction (AMI) can ensure quick and effective treatment but only 20% of adults with emergency admissions for chest pain have an AMI. High-sensitivity cardiac troponin (hs-cTn) assays may allow rapid rule-out of AMI and avoidance of unnecessary hospital admissions and anxiety.
OBJECTIVE: To assess the clinical effectiveness and cost-effectiveness of hs-cTn assays for the early (within 4 hours of presentation) rule-out of AMI in adults with acute chest pain.
METHODS: Sixteen databases, including MEDLINE and EMBASE, research registers and conference proceedings, were searched to October 2013. Study quality was assessed using QUADAS-2. The bivariate model was used to estimate summary sensitivity and specificity for meta-analyses involving four or more studies, otherwise random-effects logistic regression was used. The health-economic analysis considered the long-term costs and quality-adjusted life-years (QALYs) associated with different troponin (Tn) testing methods. The de novo model consisted of a decision tree and Markov model. A lifetime time horizon (60 years) was used.
RESULTS: Eighteen studies were included in the clinical effectiveness review. The optimum strategy, based on the Roche assay, used a limit of blank (LoB) threshold in a presentation sample to rule out AMI [negative likelihood ratio (LR-) 0.10, 95% confidence interval (CI) 0.05 to 0.18]. Patients testing positive could then have a further test at 2 hours; a result above the 99th centile on either sample and a delta (Δ) of ≥ 20% has some potential for ruling in an AMI [positive likelihood ratio (LR+) 8.42, 95% CI 6.11 to 11.60], whereas a result below the 99th centile on both samples and a Δ of < 20% can be used to rule out an AMI (LR- 0.04, 95% CI 0.02 to 0.10). The optimum strategy, based on the Abbott assay, used a limit of detection (LoD) threshold in a presentation sample to rule out AMI (LR- 0.01, 95% CI 0.00 to 0.08). Patients testing positive could then have a further test at 3 hours; a result above the 99th centile on this sample has some potential for ruling in an AMI (LR+ 10.16, 95% CI 8.38 to 12.31), whereas a result below the 99th centile can be used to rule out an AMI (LR- 0.02, 95% CI 0.01 to 0.05). In the base-case analysis, standard Tn testing was both most effective and most costly. Strategies considered cost-effective depending upon incremental cost-effectiveness ratio thresholds were Abbott 99th centile (thresholds of < £6597), Beckman 99th centile (thresholds between £6597 and £30,042), Abbott optimal strategy (LoD threshold at presentation, followed by 99th centile threshold at 3 hours) (thresholds between £30,042 and £103,194) and the standard Tn test (thresholds over £103,194). The Roche 99th centile and the Roche optimal strategy [LoB threshold at presentation followed by 99th centile threshold and/or Δ20% (compared with presentation test) at 1-3 hours] were extendedly dominated in this analysis.
CONCLUSIONS: There is some evidence to suggest that hs-CTn testing may provide an effective and cost-effective approach to early rule-out of AMI. Further research is needed to clarify optimal diagnostic thresholds and testing strategies.
STUDY REGISTRATION: This study is registered as PROSPERO CRD42013005939. FUNDING: The National Institute for Health Research Health Technology Assessment programme
Deformation and fracture of concrete under short-term tensile loading
SIGLEAvailable from British Library Document Supply Centre- DSC:D88611 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Effect of aqueous extract from Marjoram against Salmonella and cholera bacteria
Five different bacterial isolates [ Vibrio cholera (Ogawa) , Vibrio cholera (Inaba) , Salmonella typhi , Salmonella paratyphi and ? Salmonella typhimurium ] were obtained from the Central Health Laboratory . Both sensitivity tests (MIC , MBC and wells method ) against these bacteria were performed by using the aqueous of leaves extract of Marjoram plant. The results cleared that the values of MIC for Vibrio cholera serotypes Ogawa and Inaba were 100 mg/ml , while the value of MBC was 200 mg/ml. The value of the Inhibition zone at 100 mg /ml concentration for both Ogawa and Inaba were 13 mm and 9 mm respectively. Our results showed that the three types of Salmonella didn’t show any inhibition zone at 200 mg/ml
The innocent bystander: papillary fibroelastoma
Andrew Li, Shah M. Azarisman, Karen S. L. Teo, Matthew I. Worthley, Samuel Sidharta, Timothy Glenie, Luay Samaraie, SK Chua, Timothy J. Bailie, Robert Stuklis, Stephen G. Worthle
Remote Myocardium Characterisation by Pre-contrast T1 and T2* Mapping Post Myocardial Infarction
Tissue injury characterization by pre-contrast T1 mapping post myocardial infraction
Background
Myocardial scar and edema can be assessed by late gadolinium enhancement (LGE) and T2W cardiac magnetic resonance (CMR) respectively, but each has important limitations. T1-mapping has emerged as an alternative method to characterize acute ischemic injury and contemporary mapping sequences make this clinically feasible. We assessed the T1 relaxation time in myocardial segments exhibiting varying degrees of ischemic injury in patients after acute MI.
Methods
T2W, T1-mapping (using Shortened Modified Look-Looker Inversion recovery sequence) and LGE imaging was performed 24-72 hours after MI on a 1.5T scanner. Assessment of acute segmental damage, in a 16-segment AHA model, was performed on matched short axis slices. Mean segmental T1 values were calculated for infarcted, adjacent/edema, microvascular obstruction (MVO) or remote segments as defined by LGE