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1.
Clin Chim Acta ; 487: 216-221, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30296440

RESUMO

BACKGROUND: International recommendations on high-sensitivity cardiac troponin (hs-cTn) testing recommend that laboratories select only one sample type for testing. We evaluated the Siemens ADVIA Centaur hs-cTnI assay in serum and thereby provide information on imprecision, long-term storage stability, freeze-thaw stability, method comparison to other hs-cTnI assays, and clinical performance. METHODS: Patients with chest pain onset <6 h who already had Roche hs-cTnT, Beckman hs-cTnI and Abbott hs-cTnI results recorded and had non-thawed and frozen serum aliquots formed the study population (n = 134 patients with 305 serum aliquots obtained at either 0, 3 or 6 h stored below -70 °C since 2003) for measurement with the Siemens hs-cTnI assay in 2018. Receiver-operating characteristic curve analyses for myocardial infarction (MI) using the highest obtained hs-cTn concentration was performed. Additional comparison testing on serum samples stored frozen (at -70 °C for <1 month in 2018) for the Siemens and Abbott hs-cTnI assays were performed, as well as precision testing in serum pools and freeze-thaw stability testing. RESULTS: The Siemens hs-cTnI assay had an area under the curve (AUC) of 0.978 (95%CI: 0.937-0.996) for MI in the study cohort (Roche hs-cTnT AUC = 0.965 and Abbott AUC = 0.973). The Siemens hs-cTnI assay yielded higher cTnI concentrations than the other hs-cTn assays, with the same proportional bias (slope = 1.4) between the Siemens and Abbott hs-cTnI assays obtained from serum samples collected in 2003 and 2018. Over 3 months, a low serum pool of 3.5 ng/l achieved a CV of 20% (SD = 0.7, n = 42) and a high serum pool of 820 ng/l achieved a CV of 2.3% (SD = 20, n = 42). Three different serum pools recovered within 10% from baseline concentration after 5 freeze-thaw cycles for the Siemens hs-cTnI assay. CONCLUSIONS: In serum, the Siemens ADVIA Centaur hs-cTnI assay had excellent clinical performance for MI in an early chest pain onset population, acceptable precision at normal and highly elevated cTnI concentrations, long-term storage stability (15 y storage below -70 °C) and acceptable freeze-thaw stability, all of which supports serum as an acceptable sample type to use in clinical studies and in clinical practice.


Assuntos
Análise Química do Sangue , Troponina I/sangue , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC
2.
Chem Asian J ; 13(23): 3611-3622, 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30216690

RESUMO

Sequence-control in synthetic polymers is an important contemporary research area because it provides the opportunity to create completely novel materials for structure-function studies. This is especially relevant for biomimetic polymers, bioactive and information security materials. The level of control is strongly dependent and inherent upon the polymerization technique utilized. Today, the most established method yielding monodispersity and monomer sequence-definition is solid-phase synthesis. This Focus Review highlights recent advances in solid-phase strategies to access synthetic, sequence-defined macromolecules. Alternatives strategies towards sequence-defined macromolecules are also briefly summarized.

4.
CMAJ ; 190(33): E974-E984, 2018 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-30127037

RESUMO

BACKGROUND: Testing for high-sensitivity cardiac troponin (hs-cTn) may assist triage and clinical decision-making in patients presenting to the emergency department with symptoms of acute coronary syndrome; however, this could result in the misclassification of risk because of analytical variation or laboratory error. We sought to evaluate a new laboratory-based risk-stratification tool that incorporates tests for hs-cTn, glucose level and estimated glomerular filtration rate to identify patients at risk of myocardial infarction or death when presenting to the emergency department. METHODS: We constructed the clinical chemistry score (CCS) (range 0-5 points) and validated it as a predictor of 30-day myocardial infarction (MI) or death using data from 4 cohort studies involving patients who presented to the emergency department with symptoms suggestive of acute coronary syndrome. We calculated diagnostic parameters for the CCS score separately using high-sensitivity cardiac troponin I (hs-cTnI) and high-sensitivity cardiac troponin T (hs-cTnT). RESULTS: For the combined cohorts (n = 4245), 17.1% of participants had an MI or died within 30 days. A CCS score of 0 points best identified low-risk participants: the hs-cTnI CCS had a sensitivity of 100% (95% confidence interval [CI] 99.5%-100%), with 8.9% (95% CI 8.1%-9.8%) of the population classified as being at low risk of MI or death within 30 days; the hs-cTnT CCS had a sensitivity of 99.9% (95% CI 99.2%-100%), with 10.5% (95% CI 9.6%-11.4%) of the population classified as being at low risk. The CCS had better sensitivity than hs-cTn alone (hs-cTnI < 5 ng/L: 96.6%, 95% CI 95.0%-97.8%; hs-cTnT < 6 ng/L: 98.2%, 95% CI 97.0%-99.0%). A CCS score of 5 points best identified patients at high risk (hs-cTnI CCS: specificity 96.6%, 95% CI 96.0%-97.2%; 11.2% [95% CI 10.3%-12.2%] of the population classified as being at high risk; hs-cTnT CCS: specificity 94.0%, 95% CI 93.1%-94.7%; 13.1% [95% CI 12.1%-14.1%] of the population classified as being at high risk) compared with using the overall 99th percentiles for the hs-cTn assays (specificity of hs-cTnI 93.2%, 95% CI 92.3-94.0; specificity of hs-cTnT 73.8%, 95% CI 72.3-75.2). INTERPRETATION: The CCS score at the chosen cut-offs was more sensitive and specific than hs-cTn alone for risk stratification of patients presenting to the emergency department with suspected acute coronary syndrome. Study registration: ClinicalTrials.gov, nos. NCT01994577; NCT02355457.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Técnicas de Laboratório Clínico , Miocárdio/química , Troponina I/análise , Troponina T/análise , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia/análise , Morte , Serviço Hospitalar de Emergência , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Tempo
5.
Sci Rep ; 8(1): 12234, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-30111806

RESUMO

We report a one-pot, three-minute synthesis of carboxylic acid-decorated fluorescent carbon dots (COOH-FCDs) with tuneable core morphology dependent on the surface passivating agent. Mechanism investigations highlighted the presence of key pyrazine and polyhydroxyl aromatic motifs, which are formed from the degradation of glucosamine in the presence of a bifunctional linker bearing acid and amine groups. The novel COOH-FCDs are selective Fe3+ and hemin sensors. Furthermore, the FCDs are shown to be non-toxic, fluorescent bioimaging agents for cancer cells.

6.
Nanoscale ; 10(29): 13908-13912, 2018 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-29999508

RESUMO

Biomolecule functionalisation of carbon nano-dots (CDs) greatly enhances their biocompatibility and applicability, however, little is known about their molecular structure. Using an arsenal of spectroscopic and analytical techniques, we provide new insights into the physical and electronic structure of uncoated and glycan-functionalised CDs. Our studies reveal that surface functionalisation does not always result in a homogenous corona surrounding the core, and the choice of carbohydrate significantly affects the electronic structure of the surface CD states. Further, the average surface coverage of an ensemble of CDs can be probed via transient absorption spectroscopy. These findings have implications for CDs targeted at interactions with biological systems or local sensors.

7.
Clin Chim Acta ; 479: 166-170, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29366835

RESUMO

BACKGROUND: Clinicians regularly observe increased high-sensitivity cardiac troponin (hs-cTn) concentrations in patients with low estimated glomerular filtration rate (eGFR). The challenge is to differentiate acute coronary syndrome (ACS) from increased hs-cTn results across a range of eGFR. The objective of this study was to determined the optimal hs-cTn concentrations for acute myocardial infarction (MI) and a composite cardiovascular outcome across different eGFR ranges and to assess the utility of a low hs-cTn cutoff to rule-out events. METHODS: We undertook an observational study in the emergency department of patients (n = 1212) with symptoms suggestive of ACS who had an eGFR and at least one Roche hs-cTnT and one Abbott hs-cTnI result. The 7-day outcomes were MI or a composite of MI, unstable angina, congestive heart failure, serious ventricular cardiac arrhythmia, or death. The maximum hs-cTn concentration was assessed across different eGFR ranges (<30,30-59,60-89,≥90 ml/min/1.73m2) by spearman correlation, ROC-curve analyses, and sensitivity and negative predictive value (NPV) for the proposed rule-out hs-cTn cutoffs (hs-cTnI<5 ng/l and hs-cTnT<6 ng/l) for the outcomes. RESULTS: Both hs-cTnI and hs-cTnT concentrations were negatively correlated with eGFR. The lower the eGFR, the lower the AUC and the higher the optimal hs-cTn cutoffs for both MI and the composite outcome. The highest combined sensitivity (100%), NPV (100%) and proportion of low-risk for MI (45% of group) was observed for patients with hs-cTnT<6 ng/l with an eGFR≥90. CONCLUSION: The test performance for hs-cTn for diagnosing or ruling-out an acute cardiac event varies per the eGFR. Accurate risk stratification requires knowledge of the eGFR.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Serviço Hospitalar de Emergência , Taxa de Filtração Glomerular , Infarto do Miocárdio/sangue , Troponina I/sangue , Troponina T/sangue , Estudos de Coortes , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/cirurgia
8.
Ann Clin Biochem ; 55(5): 604-607, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29169258

RESUMO

Background There is interest in utilizing different cut-offs per sex for high-sensitivity cardiac troponin I (hs-cTnI) but less so for high-sensitivity cardiac troponin T (hs-cTnT) for patient management in the acute setting. Our objective was to assess if differences in hs-cTn concentrations exist between males and females for an acute cardiac outcome following the presentation measurement in the emergency department. Methods An observational emergency department population with hs-cTn measurements (Roche Diagnostics and Abbott Diagnostics) at presentation with seven-day outcomes for a composite acute cardiac outcome (i.e. myocardial infarction, unstable angina, ventricular arrhythmia, heart failure or cardiovascular death) (ClinicalTrials.gov: NCT01994577). Receiver operating characteristic curve analyses were performed for each sex with both hs-cTn assays. Results In those patients who had a composite acute cardiac outcome ( n = 128 females; n = 145 males), there was no difference in hs-cTn concentrations between the sexes (median [IQR] female hs-cTnT = 35 ng/L [21-69] vs. male hs-cTnT = 38 ng/L [19-77], P = 0.95; and median [IQR] female hs-cTnI = 27 ng/L [12-75] vs. male hs-cTnI = 26 ng/L [12-85], P = 0.97]. There was also no difference in the area under the curve between the hs-cTn assays and between the sexes ( P > 0.10). Comparing hs-cTn concentrations in those patients with the composite outcome between the sexes <60 years and ≥60 years of age also did not yield significant differences ( P > 0.70). Conclusions The concentrations and area under the curves of hs-cTnT and hs-cTnI at patient presentation in the emergency department for an acute composite cardiac outcome were similar between the sexes in this exploratory study.


Assuntos
Cardiopatias/diagnóstico , Troponina I/sangue , Troponina T/sangue , Idoso , Idoso de 80 Anos ou mais , Serviço Hospitalar de Emergência , Feminino , Humanos , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Curva ROC , Fatores Sexuais
9.
Clin Chim Acta ; 475: 51-55, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29017768

RESUMO

BACKGROUND: Concerns have been raised on the long-term analytical performance of high-sensitivity cardiac troponin (hs-cTn) assays with respect to different reagent formulations, lots and instrumentation. Our goal for the present study was to compare three different versions of an hs-cTnI assay in two different study populations to evaluate if assay re-formulation over 10years has also affected the analytical results. METHODS: Beckman Coulter's CE marked hs-cTnI assay (Access hsTnI, 2017) was tested in 100 lithium heparin plasma samples first tested in 2007 with their prototype hs-cTnI assay and in 100 serum samples tested with their enhanced hs-cTnI assay in 2011 with comparison performed by Passing-Bablok regression. The Beckman Coulter hs-cTnI results from 2017 and 2011 from the serum samples were also compared to the Abbott ARCHITECT i1000 hs-cTnI results (2013) with 3-fold differences used to identify possible outliers. Freeze/thaw stability testing (-20°C) was also performed on normal cTnI (Beckman=4.0ng/L; Abbott=5.3ng/L) and high cTnI concentration (Beckman=77.6ng/L; Abbott=126.1ng/L) lithium heparin plasma pools for both hs-cTnI assays. RESULTS: After 3 freeze-thaws the Beckman hs-cTnI assay yielded minor decreases in concentrations (normal pool -0.7ng/L and high pool -12.6ng/L lower). Regression analyses yielded the following relationship between the Beckman hs-cTnI versions: 2017 hs-cTnI=2.0*(2007 prototype hs-cTnI)-5.1ng/L and 2017 hs-cTnI=1.04∗(2011 enhanced hs-cTnI)-2.5ng/L. Compared to the Abbott 2013 hs-cTnI results, the 2011 Beckman enhanced version had 8 results 3-fold higher, with the 2017 Beckman version yielding 6 results 3-fold lower. CONCLUSIONS: The 2017 Beckman hs-cTnI version (Access hsTnI) is closely aligned with the previous enhanced hs-cTnI assay and appears to have reduced the frequency of aberrantly high results.


Assuntos
Automação Laboratorial/normas , Bioensaio/normas , Proteínas Sanguíneas/análise , Troponina I/sangue , Bioensaio/instrumentação , Congelamento , Humanos , Plasma/química , Análise de Regressão , Reprodutibilidade dos Testes , Fatores de Tempo
10.
Can J Cardiol ; 33(7): 898-903, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28668141

RESUMO

The optimal high-sensitivity cardiac troponin (hs-cTn) cutoffs for determining risk in patients who present with acute coronary syndrome symptoms are unknown. In 1137 emergency department patients we calculated adjusted relative risks for a composite outcome (myocardial infarction, unstable angina, heart failure, ventricular arrhythmia, or cardiovascular death) within 7 days for the presentation of hs-cTnT (Roche) and hs-cTnI (Abbott) assay concentrations on the basis of literature cutoffs. Patients with hs-cTn concentrations ≥ 14 ng/L had an adjusted relative risk of 4.9 for the composite outcome, with different hs-cTnT/hs-cTnI concentration ranges yielding higher risks. A common low-risk cutoff of 14 ng/L may be used for hs-cTn with higher cutoffs identifying high-risk patients.


Assuntos
Serviço Hospitalar de Emergência , Cardiopatias/diagnóstico , Troponina I/sangue , Doença Aguda , Biomarcadores/sangue , Causas de Morte/tendências , Seguimentos , Cardiopatias/sangue , Cardiopatias/epidemiologia , Humanos , Incidência , Ontário/epidemiologia , Prevalência , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Fatores de Risco , Taxa de Sobrevida/tendências
11.
Clin Chim Acta ; 469: 69-74, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28342713

RESUMO

BACKGROUND: We evaluated whether a low high-sensitivity cardiac troponin (hs-cTn) cutoff combined with glucose, red cell distribution width (RDW), and the estimated glomerular filtration rate (eGFR) can be used to rule-out a serious cardiac outcome or death in patients presenting with symptoms suggestive of acute coronary syndrome (ACS). METHODS: This was a prospective observational emergency department (ED) study enrolling consecutive patients presenting with symptoms suggestive of ACS (ClinicalTrials.gov: NCT01994577). The primary outcome was a 7-day composite of myocardial infarction, unstable angina, decompensated congestive heart failure, serious ventricular cardiac arrhythmia, or death. A laboratory score combining glucose, RDW, eGFR with hs-cTnT (Roche) or hs-cTnI (Abbott) was compared to hs-cTn alone using the limit of detection (LoD; hs-cTnT<5ng/l/hs-cTnI<2ng/l) as the cutoff. A benchmark of >99% sensitivity was used to assess the laboratory panel with hs-cTn versus the LoD alone to identify low-risk patients suitable for discharge. RESULTS: A total of 1095 patients (n=267 composite-outcomes) had measurements of glucose, RDW, eGFR, hs-cTnT, and hs-cTnI at presentation. Applying the hs-cTn LoD alone as the cutoff missed 5 composite-outcomes (sensitivity=98.1%), however the addition of the laboratory panel to the hs-cTn LoD increased the sensitivity to >99% with approximately 10% of the population identified as low-risk. The percentage of low-risk patients was increased to 15% (1 composite-outcome missed) when employing a low measurable hs-cTnI cutoff with the laboratory panel (laboratory score<2 points). CONCLUSION: A laboratory score with hs-cTn may identify low-risk patients suitable for ED discharge at presentation.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Técnicas de Laboratório Clínico , Miocárdio/metabolismo , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/metabolismo , Síndrome Coronariana Aguda/fisiopatologia , Adulto , Glicemia/metabolismo , Morte , Serviço Hospitalar de Emergência , Contagem de Eritrócitos , Taxa de Filtração Glomerular , Humanos , Prognóstico , Troponina/metabolismo
12.
Clin Chem ; 63(1): 403-414, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28062631

RESUMO

BACKGROUND: Early rule-in/rule-out of myocardial infarction (MI) in patients presenting to the emergency department (ED) is important for patient care and resource allocation. Given that dysglycemia is a strong risk factor for MI, we sought to explore and compare different combinations of cardiac troponin (cTn) cutoffs with glycemic markers for the early rule-in/rule-out of MI. METHODS: We included ED patients (n = 1137) with symptoms suggestive of acute coronary syndrome (ACS) who had cTnI, high-sensitivity cTnI (hs-cTnI), hs-cTnT, glucose, and hemoglobin A1c (Hb A1c) measurements. We derived rule-in/rule-out algorithms using different combinations of ROC-derived and literature cutoffs for rule-in and rule-out of MI within 7 days after presentation. These algorithms were then tested for MI/cardiovascular death and ACS/cardiovascular death at 7 days. ROC curves, sensitivity, specificity, likelihood ratios, positive and negative predictive values (PPV and NPV), and CIs were determined for various biomarker combinations. RESULTS: MI was diagnosed in 133 patients (11.7%; 95% CI, 9.8-13.8). The algorithms that included cTn and glucose produced the greatest number of patients ruled out/ruled in for MI and yielded sensitivity ≥99%, NPV ≥99.5%, specificity ≥99%, and PPV ≥80%. This diagnostic performance was maintained for MI/cardiovascular death but not for ACS/cardiovascular death. The addition of hemoglobin A1c (Hb A1c) (≥6.5%) to these algorithms did not change these estimates; however, 50 patients with previously unknown diabetes may have been identified if Hb A1c was measured. CONCLUSIONS: Algorithms incorporating glucose with cTn may lead to an earlier MI diagnosis and rule-out for MI/cardiovascular death. Addition of Hb A1c into these algorithms allows for identification of diabetes. Future studies extending these findings are needed for ACS/cardiovascular death. ClinicalTrials.gov identifier: NCT01994577.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Glicemia/análise , Infarto do Miocárdio/diagnóstico , Troponina I/sangue , Troponina T/sangue , Síndrome Coronariana Aguda/sangue , Idoso , Algoritmos , Biomarcadores/sangue , Estudos de Coortes , Feminino , Humanos , Masculino , Infarto do Miocárdio/sangue , Curva ROC
13.
Clin Chem ; 63(2): 593-602, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27811206

RESUMO

BACKGROUND: We have previously demonstrated the utility of a rule-in/rule-out strategy for myocardial infarction (MI) using glycemic biomarkers in combination with cardiac troponin in the emergency department (ED). Given that the cost of assessing patients with possible MI in the ED is increasing, we sought to compare the health services cost of our previously identified early rule-in/rule-out approaches for MI among patients who present to the ED with symptoms suggestive of acute coronary syndrome (ACS). METHODS: We compared the cost differences between different rule-in/rule-out strategies for MI using presentation cardiac troponin I (cTnI), high-sensitivity cTnI (hs-cTnI), high-sensitivity cardiac troponin T (hs-cTnT), glucose, and/or hemoglobin A1c (Hb A1c) in 1137 ED patients (7-day MI n = 133) as per our previously defined algorithms and compared them with the European Society of Cardiology (ESC) 0-h algorithm-cutoffs. Costs associated with each decision model were obtained from site-specific sources (length of stay) and provincial sources (Ontario Case Costing Initiative). RESULTS: Algorithms incorporating cardiac troponin and glucose for early rule-in/rule-out were the most cost effective and clinically safest methods (i.e., ≤1 MI missed) for early decision making, with hs-cTnI and glucose yielding lower costs compared to cTnI and glucose, despite the higher price for the hs-cTnI test. The addition of Hb A1c to the algorithms increased the cost of these algorithms but did not miss any additional patients with MI. Applying the ESC 0-h algorithm-cutoffs for hs-cTnI and hs-cTnT were the most costly. CONCLUSIONS: Rule-in/rule-out algorithms incorporating presentation glucose with high-sensitivity cardiac troponin are the safest and most cost-effective options as compared to the ESC 0-h algorithm-cutoffs.


Assuntos
Algoritmos , Glicemia/análise , Serviço Hospitalar de Emergência/economia , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/economia , Troponina I/sangue , Troponina T/sangue , Biomarcadores/análise , Estudos de Coortes , Humanos , Infarto do Miocárdio/sangue , Troponina I/economia , Troponina T/economia
14.
Nanoscale ; 8(44): 18630-18634, 2016 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-27801469

RESUMO

A one-pot, three-minute, gram-scale synthesis of novel sp3-nanocrystalline, water-soluble, and fluorescent carbon dots (FCDs), from simple and cheap sugar starting materials is described. Mechanism studies showed that NH2-FCD formation proceeds via a crucial imine intermediate derived from reaction between a sugar hemiacetal and an amine. Moreover, we successfully demonstrate the utility of lactose functionalized FCDots (Lac-FCDots) as non-toxic fluorescent intracellular delivery vehicles.


Assuntos
Carboidratos/química , Carbono , Portadores de Fármacos/química , Pontos Quânticos , Aminas , Fluorescência
16.
CJEM ; 17(1): 62-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25781385

RESUMO

INTRODUCTION: Not all patients with suspected acute coronary syndrome (ACS) receiving cardiac troponin (cTn) testing present to the emergency department (ED) with cardiac chest pain. Since elderly patients (age ≥70) have increased morbidity and mortality associated with ACS, complaints other than cardiac chest pain may justify cTn testing. Our primary objective was to characterize the population of ED patients who receive cTn testing. The secondary objective was to determine if elderly patients underwent cTn testing for different presenting complaints than their younger counterparts. METHODS: We created an electronic database including Canadian Emergency Department Information Systems (CEDIS) presenting complaints, age, sex, disposition, and Canadian Triage Acuity Scale (CTAS) score, for patients who received cTn testing in three Canadian EDs during 2011. We analyzed the data for patient characteristics and sorted by age (<70 and ≥70) for further analysis. RESULTS: In the 15,824 included patients, the average age was 66 (51%<70; 51% female). The most common presenting complaints were cardiac chest pain (n=3,267) and shortness of breath (n=2,266). The elderly underwent cTn testing for significantly (p<0.0001) different complaints than their younger counterparts. They more commonly presented with generalized weakness (n=898), whereas younger patients more frequently had abdominal pain (n=576). CONCLUSIONS: Cardiac chest pain and shortness of breath are presenting complaints in one-third of patients undergoing ED cTn testing. The majority of patients undergoing cTn testing did not have typical ACS symptoms. Half of all cTn testing in the ED is on the elderly, who present with different complaints than their younger counterparts.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Dor no Peito/diagnóstico , Serviço Hospitalar de Emergência , Triagem , Troponina/sangue , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/complicações , Idoso , Canadá , Dor no Peito/sangue , Dor no Peito/etiologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Clin Biochem ; 48(4-5): 282-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25448027

RESUMO

OBJECTIVES: The application of "undetectable" high-sensitivity cardiac troponin (hs-cTn) concentrations to "rule-out" myocardial infarction is appealing, but there are analytical concerns and a lack of consensus on what concentration should be used to define the lower reportable limit; i.e., limit of detection (LoD) or limit of blank. An alternative approach is to utilize a measurable hs-cTn concentration that identifies patients at low-risk for a future cardiovascular event combined with another prognostic test, such as glucose. We assessed both of these approaches in different emergency department (ED) cohorts to rule-out an event. DESIGN AND METHODS: We used cohort 1 (all-comer ED population, n=4773; derivation cohort) to determine the most appropriate approach at presentation (i.e., Dual Panel test: hs-cTn/glucose vs. LoD vs. LoD/glucose) for an early rule-out of hospital death using the Abbott ARCHITECT hs-cTnI assay. We used cohort 2 (n=144) and cohort 3 (n=127), both early chest pain onset ED populations as the verification datasets (outcome: composite cardiovascular event at 72h) with three hs-cTn assays assessed (Abbott Laboratories, Beckman Coulter, Roche Diagnostics). RESULTS: In cohort 1, the sensitivity was >99% for all three approaches; however the specificity (11%; 95% CI: 10-12%) was significantly higher for the Dual Panel as compared to the LoD approach (specificity=5%; 95% CI: 4-6%). Verification of the Dual Panel in cohort 2 and cohort 3 revealed 100% sensitivity and negative predictive values for all three hs-cTn assays. CONCLUSIONS: The combination of a "healthy" hs-cTn concentration with glucose might effectively rule-out patients for an acute cardiovascular event at ED presentation.


Assuntos
Bioensaio/normas , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/mortalidade , Serviço Hospitalar de Emergência/normas , Glucose/metabolismo , Troponina I/sangue , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/mortalidade , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Bioensaio/métodos , Biomarcadores/sangue , Doenças Cardiovasculares/diagnóstico , Dor no Peito/sangue , Dor no Peito/diagnóstico , Dor no Peito/mortalidade , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/mortalidade
18.
Heart Fail Rev ; 19(4): 521-40, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25120174

RESUMO

The aim of this study was to determine whether measurement of natriuretic peptides independently adds incremental predictive value for mortality and morbidity in patients with chronic stable heart failure (CSHF). We electronically searched Medline®, Embase™, AMED, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and CINAHL from 1989 to June 2012. We also searched reference lists of included articles, systematic reviews, and the gray literature. Studies were screened for eligibility criteria and assessed for methodological quality. Data were extracted on study design, population demographics, assay cutpoints, prognostic risk prediction model covariates, statistical methods, outcomes, and results. One hundred and eighty-three studies were identified as prognostic in the systematic review. From these, 15 studies (all NT-proBNP) considered incremental predictive value in CSHF subjects. Follow-up varied from 12 to 37 months. All studies presented at least one estimate of incremental predictive value of NT-proBNP relative to the base prognostic model. Using discrimination or likelihood statistics, these studies consistently showed that NT-proBNP increased model performance. Three studies used re-classification and model validation computations to establish incremental predictive value; these studies showed less consistency with respect to added value. Although there were differences in the base risk prediction models, assay cutpoints, and lengths of follow-up, there was consistency in NT-proBNP adding incremental predictive value for prognostic models in chronic stable CSHF patients. The limitations in the literature suggest that studies designed to evaluate prognostic models should be undertaken to evaluate the incremental value of natriuretic peptide as a predictor of mortality and morbidity in CSHF.


Assuntos
Insuficiência Cardíaca , Peptídeos Natriuréticos/sangue , Vigilância da População , Biomarcadores/sangue , Saúde Global , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Humanos , Morbidade , Valor Preditivo dos Testes , Prognóstico , Taxa de Sobrevida
19.
Heart Fail Rev ; 19(4): 553-64, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25074674

RESUMO

BNP/NT-proBNP measurement has not gained widespread use for the management of patients with heart failure (HF) despite several randomized controlled trials. A systematic review addressing the question of whether patients with HF benefit from BNP-assisted therapy or intensified therapy compared with usual care was undertaken. Relevant randomized controlled trial (RCTs) were selected by searching Medline, Embase, AMED, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and CINAHL for English-language articles published from 1980 to 2012. Selected studies required patients to be treated for chronic HF with medical therapy based on BNP/NT-proBNP or usual care. There were no restrictions except that BNP/NT-proBNP measurement had to be done by an FDA approved method. Nine RCTs were identified with 2,104 patients with study duration that ranged from 3 to 18 months. Overall, there was a wide variation in study design and how parameters were reported including patient selection, baseline characteristics, therapy goals, BNP/NT-proBNP cutpoint, and outcome types. Meta-analysis was not appropriate given this study heterogeneity. The strength of evidence for the outcome of mortality, reported in seven studies, was found to be low due to inconsistency and imprecision. This systematic review showed that the evidence is of low quality and insufficient to support the use of BNP/NT-proBNP to guide HF therapy. Further trials with improved design are needed.


Assuntos
Gerenciamento Clínico , Insuficiência Cardíaca , Peptídeo Natriurético Encefálico/sangue , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Humanos , Resultado do Tratamento
20.
Heart Fail Rev ; 19(4): 507-19, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25052418

RESUMO

The aim of this systematic review was to determine whether B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) independently add incremental value for predicting mortality and morbidity in patients with acute decompensated heart failure (ADHF). Medline(®), Embase™, AMED, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and CINAHL were searched from 1989 to June 2012. We also searched reference lists of included articles, systematic reviews, and the gray literature. Studies were screened for eligibility criteria and assessed for risk of bias. Data were extracted on study design, population demographics, assay cutpoints, prognostic risk prediction model covariates, statistical methods, outcomes, and results. From 183 citations, only seven studies (5 BNP and 2 NT-proBNP) considered incremental value in ADHF subjects admitted to acute care centers. Admission assay levels and length of follow-up varied for BNP studies (31 days to 12 months) and for NT-proBNP studies (25-82 months). All studies presented at least one estimate of incremental value of BNP/NT-proBNP relative to the base prognostic model. Using discrimination or likelihood statistics, these studies consistently showed that BNP or NT-proBNP increased model performance. Three studies used reclassification and model validation computations to establish incremental value; these studies showed less consistency with respect to added value. In conclusion, the literature assessing incremental value of BNP/NT-proBNP in ADHF populations is limited to seven studies evaluating only mortality outcomes and at moderate risk of bias. Although there were differences in the base risk prediction models, assay cutpoints, and lengths of follow-up, there was consistency in BNP/NT-proBNP adding incremental value in prediction models in ADHF patients.


Assuntos
Insuficiência Cardíaca/sangue , Peptídeo Natriurético Encefálico/sangue , Doença Aguda , Biomarcadores/sangue , Saúde Global , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Humanos , Valor Preditivo dos Testes , Prognóstico , Taxa de Sobrevida
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