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1.
Circulation ; 147(24): 1798-1808, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37114498

RESUMO

BACKGROUND: Cardiac troponin concentrations are lower in women than men. We examined whether age- and risk factor-related changes in cardiac troponin over the life course differ by sex and if the trajectory of cardiac troponin was informative in respect of cardiovascular outcomes in women and men in the general population. METHODS: In the Whitehall II cohort, high-sensitivity cardiac troponin I concentrations were measured on 3 occasions over a 15-year period. Using linear mixed-effects models, the sex-specific trajectories of cardiac troponin were evaluated, and the relationship with conventional cardiovascular risk factors determined. Using multistate joint models, the association between sex-specific trajectories of cardiac troponin and a composite outcome of nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death was evaluated. RESULTS: In 2142 women and 5151 men (mean, 58±7 and 57±7 years of age, respectively), there were 177 (8.3%) and 520 (10.1%) outcome events, respectively, during a median follow-up of 20.9 (25th to 75th percentile, 15.8-21.3) years. Cardiac troponin concentrations were persistently lower in women than in men (median baseline concentration: 2.4 [25th to 75th percentile, 1.7-3.6] ng/L versus 3.7 [25th to 75th percentile, 2.6-5.8] ng/L, respectively, P<0.001), with women exhibiting a relatively larger increase with advancing age as compared with men (Pinteraction<0.001). Apart from age, a significant and divergent interaction with sex was found for the association between cardiac troponin and body mass index (BMI) (Pinteraction=0.008) and diabetes (Pinteraction=0.003). During follow-up, cardiac troponin concentrations were associated to the outcome in both women and men (adjusted hazard ratio per 2-fold difference [95% CI, 1.34 (1.17-1.52) and 1.30 (1.21-1.40), respectively], Pinteraction=0.752). The slope of cardiac troponin was significantly associated with the outcome in women, but not in men (adjusted hazard ratio [95% CI, 2.70 (1.01-7.33) and 1.31 (0.62-2.75), respectively], Pinteraction=0.250). CONCLUSIONS: Trajectories of cardiac troponin differ between women and men in the general population, with differing associations to conventional risk factors and cardiovascular outcomes. Our findings highlight the importance of a sex-specific approach when serial cardiac troponin testing is applied for cardiovascular risk prediction.


Assuntos
Acontecimentos que Mudam a Vida , Infarto do Miocárdio , Humanos , Masculino , Feminino , Biomarcadores , Caracteres Sexuais , Troponina I , Troponina T
2.
Am Heart J ; 271: 182-187, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38658076

RESUMO

In the Emergency Department, patients with suspected myocardial infarction can be risk stratified using the HEART pathway, which has recently been amended for prehospital use and modified for the incorporation of a high-sensitivity cardiac troponin test. In a prospective analysis, the performance of both HEART pathways in the prehospital setting, with a high-sensitivity cardiac troponin test using 3 different thresholds, was evaluated for major adverse cardiac events at 30 days. We found that both low-risk HEART pathways, when using the most conservative cardiac troponin thresholds, approached but did not reach accepted rule-out performance in the Emergency Department.


Assuntos
Serviços Médicos de Emergência , Infarto do Miocárdio , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/sangue , Serviços Médicos de Emergência/métodos , Estudos Prospectivos , Medição de Risco/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Biomarcadores/sangue , Serviço Hospitalar de Emergência , Pessoal Técnico de Saúde , Troponina/sangue , Auxiliares de Emergência , Paramédico
3.
Circulation ; 145(16): 1188-1200, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35341327

RESUMO

BACKGROUND: Type 2 myocardial infarction is caused by myocardial oxygen supply-demand imbalance, and its diagnosis is increasingly common with the advent of high-sensitivity cardiac troponin assays. Although this diagnosis is associated with poor outcomes, widespread uncertainty and confusion remain among clinicians as to how to investigate and manage this heterogeneous group of patients with type 2 myocardial infarction. METHODS: In a prospective cohort study, 8064 consecutive patients with increased cardiac troponin concentrations were screened to identify patients with type 2 myocardial infarction. We excluded patients with frailty or renal or hepatic failure. All study participants underwent coronary (invasive or computed tomography angiography) and cardiac (magnetic resonance or echocardiography) imaging, and the underlying causes of infarction were independently adjudicated. The primary outcome was the prevalence of coronary artery disease. RESULTS: In 100 patients with a provisional diagnosis of type 2 myocardial infarction (median age, 65 years [interquartile range, 55-74 years]; 43% women), coronary and cardiac imaging reclassified the diagnosis in 7 patients: type 1 or 4b myocardial infarction in 5 and acute myocardial injury in 2 patients. In those with type 2 myocardial infarction, median cardiac troponin I concentrations were 195 ng/L (interquartile range, 62-760 ng/L) at presentation and 1165 ng/L (interquartile range, 277-3782 ng/L) on repeat testing. The prevalence of coronary artery disease was 68% (63 of 93), which was obstructive in 30% (28 of 93). Infarct-pattern late gadolinium enhancement or regional wall motion abnormalities were observed in 42% (39 of 93), and left ventricular systolic dysfunction was seen in 34% (32 of 93). Only 10 patients had both normal coronary and normal cardiac imaging. Coronary artery disease and left ventricular systolic dysfunction were previously unrecognized in 60% (38 of 63) and 84% (27 of 32), respectively, with only 33% (21 of 63) and 19% (6 of 32) on evidence-based treatments. CONCLUSIONS: Systematic coronary and cardiac imaging of patients with type 2 myocardial infarction identified coronary artery disease in two-thirds and left ventricular systolic dysfunction in one-third of patients. Unrecognized and untreated coronary or cardiac disease is seen in most patients with type 2 myocardial infarction, presenting opportunities for initiation of evidence-based treatments with major potential to improve clinical outcomes. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03338504.


Assuntos
Infarto Miocárdico de Parede Anterior , Doença da Artéria Coronariana , Infarto do Miocárdio , Disfunção Ventricular Esquerda , Idoso , Meios de Contraste , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/epidemiologia , Feminino , Gadolínio , Humanos , Masculino , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Estudos Prospectivos , Troponina I , Disfunção Ventricular Esquerda/complicações
4.
BMC Med ; 21(1): 216, 2023 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-37337233

RESUMO

BACKGROUND: High-sensitivity cardiac troponin testing is a promising tool for cardiovascular risk prediction, but whether serial testing can dynamically predict risk is uncertain. We evaluated the trajectory of cardiac troponin I in the years prior to a cardiovascular event in the general population, and determine whether serial measurements could track risk within individuals. METHODS: In the Whitehall II cohort, high-sensitivity cardiac troponin I concentrations were measured on three occasions over a 15-year period. Time trajectories of troponin were constructed in those who died from cardiovascular disease compared to those who survived or died from other causes during follow up and these were externally validated in the HUNT Study. A joint model that adjusts for cardiovascular risk factors was used to estimate risk of cardiovascular death using serial troponin measurements. RESULTS: In 7,293 individuals (mean 58 ± 7 years, 29.4% women) cardiovascular and non-cardiovascular death occurred in 281 (3.9%) and 914 (12.5%) individuals (median follow-up 21.4 years), respectively. Troponin concentrations increased in those dying from cardiovascular disease with a steeper trajectory compared to those surviving or dying from other causes in Whitehall and HUNT (Pinteraction < 0.05 for both). The joint model demonstrated an independent association between temporal evolution of troponin and risk of cardiovascular death (HR per doubling, 1.45, 95% CI,1.33-1.75). CONCLUSIONS: Cardiac troponin I concentrations increased in those dying from cardiovascular disease compared to those surviving or dying from other causes over the preceding decades. Serial cardiac troponin testing in the general population has potential to track future cardiovascular risk.


Assuntos
Doenças Cardiovasculares , Humanos , Feminino , Masculino , Estudos Longitudinais , Doenças Cardiovasculares/diagnóstico , Troponina I , Biomarcadores , Estudos de Coortes , Fatores de Risco
5.
Opt Express ; 31(15): 23910-23922, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37475231

RESUMO

A silica-based LP11 mode rotator, which is one of the basic and indispensable optical components for space division multiplexing, with multiple tapered trenches is proposed. Compared with the conventional interference-based LP11 mode rotator with a simple L-shape waveguide, the proposed LP11 mode rotator has many advantages in a mode conversion efficiency, an insertion loss, and a fabrication tolerance because the operation principle is based on the adiabatic mode conversion. By using an approach of the shortcut to adiabaticity, the proposed device is effectively miniaturized rather than the standard tapered structures. Among the LP11 mode rotators in the silica-based mode multi/demultiplexers, the proposed type will be a considerably promising candidate.

6.
Opt Express ; 31(16): 26842-26853, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710534

RESUMO

Ultracompact mode multiplexers based on mosaic structure for various wavelength bands designed by Bayesian technique are investigated. C-, O-, and C + O band, TE0-TE1 2-mode multiplexers can be designed with the same footprint, by only changing the mosaic-pattern, showing the great flexibility of mosaic-based devices. Bayesian direct binary search method is used for the design, and it is demonstrated that the Bayesian technique is superior to conventional design method in terms of the best-structure search for the same number of iterations. The designed devices are fabricated for Si-waveguide platform, and the proof-of-concept results are obtained. These results indicate that the mosaic-based devices are promising candidates for future compact optical transceivers.

7.
Emerg Med J ; 40(7): 474-481, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37268413

RESUMO

INTRODUCTION: The History, Electrocardiogram (ECG), Age, Risk Factors and Troponin (HEART) score is commonly used to risk stratify patients with possible myocardial infarction as low risk or high risk in the Emergency Department (ED). Whether the HEART score can be used by paramedics to guide care were high-sensitivity cardiac troponin testing available in a prehospital setting is uncertain. METHODS: In a prespecified secondary analysis of a prospective cohort study where paramedics enrolled patients with suspected myocardial infarction, a paramedic Heart, ECG, Age, Risk Factors (HEAR) score was recorded contemporaneously, and a prehospital blood sample was obtained for subsequent cardiac troponin testing. HEART and modified HEART scores were derived using laboratory contemporary and high-sensitivity cardiac troponin I assays. HEART and modified HEART scores of ≤3 and ≥7 were applied to define low-risk and high-risk patients, and performance was evaluated for an outcome of major adverse cardiac events (MACEs) at 30 days. RESULTS: Between November 2014 and April 2018, 1054 patients were recruited, of whom 960 (mean 64 (SD 15) years, 42% women) were eligible for analysis and 255 (26%) experienced a MACE at 30 days. A HEART score of ≤3 identified 279 (29%) as low risk with a negative predictive value of 93.5% (95% CI 90.0% to 95.9%) for the contemporary assay and 91.4% (95% CI 87.5% to 94.2%) for the high-sensitivity assay. A modified HEART score of ≤3 using the limit of detection of the high-sensitivity assay identified 194 (20%) patients as low risk with a negative predictive value of 95.9% (95% CI 92.1% to 97.9%). A HEART score of ≥7 using either assay gave a lower positive predictive value than using the upper reference limit of either cardiac troponin assay alone. CONCLUSIONS: A HEART score derived by paramedics in the prehospital setting, even when modified to harness the precision of a high-sensitivity assay, does not allow safe rule-out of myocardial infarction or enhanced rule-in compared with cardiac troponin testing alone.


Assuntos
Síndrome Coronariana Aguda , Infarto do Miocárdio , Humanos , Feminino , Masculino , Estudos Prospectivos , Síndrome Coronariana Aguda/diagnóstico , Dor no Peito/etiologia , Medição de Risco , Troponina I , Serviço Hospitalar de Emergência , Eletrocardiografia , Biomarcadores
8.
Esophagus ; 20(3): 533-540, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36750480

RESUMO

BACKGROUND: Although definitive chemoradiotherapy (CRT) is the standard therapy for patients with unresectable locally advanced esophageal squamous cell carcinoma (ESCC), poor survival has been reported. Although the complete response (CR) rate is strongly correlated with good prognosis, the predictive factors for CR have not been elucidated. METHODS: This registry study aimed to identify predictors of CR to definitive CRT in patients with unresectable locally advanced ESCC. "Unresectable" was defined as the primary lesion invading unresectable adjacent structures such as the aorta, vertebral body, and trachea (T4b), or the regional and/or supraclavicular lymph nodes invading unresectable adjacent structures (LNT4b). RESULTS: Overall, 175 patients who started definitive CRT between January 2013 and March 2020 were included. The confirmed CR (cCR) rate was 24% (42/175). The 2-year progression-free survival (PFS) and overall survival (OS) rates of cCR cases vs. non-cCR cases were 59% vs. 2% (log-rank p < 0.001) and 90% vs. 31% (log-rank p < 0.001), with a median follow-up period of 18.5 and 40.5 months, respectively. Multivariate analysis of clinicopathological factors revealed that tumor length ≥ 6 cm [odds ratio (OR) 0.446; 95% CI 0.220-0.905; p = 0.025] was a predictor of cCR. CONCLUSIONS: Favorable PFS and OS rates were observed in patients with cCR. Tumor length was a predictive factor for cCR.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/terapia , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Carcinoma de Células Escamosas/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia
9.
Circulation ; 144(7): 528-538, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34167318

RESUMO

BACKGROUND: Although the 99th percentile is the recommended diagnostic threshold for myocardial infarction, some guidelines also advocate the use of higher troponin thresholds to rule in myocardial infarction at presentation. It is unclear whether the magnitude or change in troponin concentration can differentiate causes of myocardial injury and infarction in practice. METHODS: In a secondary analysis of a multicenter randomized controlled trial, we identified 46 092 consecutive patients presenting with suspected acute coronary syndrome without ST-segment-elevation myocardial infarction. High-sensitivity cardiac troponin I concentrations at presentation and on serial testing were compared between patients with myocardial injury and infarction. The positive predictive value and specificity were determined at the sex-specific 99th percentile upper reference limit and rule-in thresholds of 64 ng/L and 5-fold of the upper reference limit for a diagnosis of type 1 myocardial infarction. RESULTS: Troponin was above the 99th percentile in 8188 patients (18%). The diagnosis was type 1 or type 2 myocardial infarction in 50% and 14% and acute or chronic myocardial injury in 20% and 16%, respectively. Troponin concentrations were similar at presentation in type 1 (median [25th-75th percentile] 91 [30-493] ng/L) and type 2 (50 [22-147] ng/L) myocardial infarction and in acute (50 [26-134] ng/L) and chronic (51 [31-130] ng/L) myocardial injury. The 99th percentile and rule-in thresholds of 64 ng/L and 5-fold upper reference limit gave a positive predictive value of 57% (95% CI, 56%-58%), 59% (58%-61%), and 62% (60%-64%) and a specificity of 96% (96%-96%), 96% (96%-96%), and 98% (97%-98%), respectively. The absolute, relative, and rate of change in troponin concentration were highest in patients with type 1 myocardial infarction (P<0.001 for all). Discrimination improved when troponin concentration and change in troponin were combined compared with troponin concentration at presentation alone (area under the curve, 0.661 [0.642-0.680] versus 0.613 [0.594-0.633]). CONCLUSIONS: Although we observed important differences in the kinetics, cardiac troponin concentrations at presentation are insufficient to distinguish type 1 myocardial infarction from other causes of myocardial injury or infarction in practice and should not guide management decisions in isolation. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01852123.


Assuntos
Biomarcadores , Traumatismos Cardíacos/diagnóstico , Traumatismos Cardíacos/metabolismo , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Troponina/sangue , Idoso , Diagnóstico Diferencial , Feminino , Traumatismos Cardíacos/etiologia , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/etiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/metabolismo , Sensibilidade e Especificidade , Troponina I/sangue , Troponina I/metabolismo
10.
Circulation ; 143(25): 2418-2427, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-33913339

RESUMO

BACKGROUND: Valvular calcification is central to the pathogenesis and progression of aortic stenosis, with preclinical and observational studies suggesting that bone turnover and osteoblastic differentiation of valvular interstitial cells are important contributory mechanisms. We aimed to establish whether inhibition of these pathways with denosumab or alendronic acid could reduce disease progression in aortic stenosis. METHODS: In a single-center, parallel group, double-blind randomized controlled trial, patients >50 years of age with calcific aortic stenosis (peak aortic jet velocity >2.5 m/s) were randomized 2:1:2:1 to denosumab (60 mg every 6 months), placebo injection, alendronic acid (70 mg once weekly), or placebo capsule. Participants underwent serial assessments with Doppler echocardiography, computed tomography aortic valve calcium scoring, and 18F-sodium fluoride positron emission tomography and computed tomography. The primary end point was the calculated 24-month change in aortic valve calcium score. RESULTS: A total of 150 patients (mean age, 72±8 years; 21% women) with calcific aortic stenosis (peak aortic jet velocity, 3.36 m/s [2.93-3.82 m/s]; aortic valve calcium score, 1152 AU [655-2065 AU]) were randomized and received the allocated trial intervention: denosumab (n=49), alendronic acid (n=51), and placebo (injection n=25, capsule n=25; pooled for analysis). Serum C-terminal telopeptide, a measure of bone turnover, halved from baseline to 6 months with denosumab (0.23 [0.18-0.33 µg/L] to 0.11 µg/L [0.08-0.17 µg/L]) and alendronic acid (0.20 [0.14-0.28 µg/L] to 0.09 µg/L [0.08-0.13 µg/L]) but was unchanged with placebo (0.23 [0.17-0.30 µg/L] to 0.26 µg/L [0.16-0.31 µg/L]). There were no differences in 24-month change in aortic valve calcium score between denosumab and placebo (343 [198-804 AU] versus 354 AU [76-675 AU]; P=0.41) or alendronic acid and placebo (326 [138-813 AU] versus 354 AU [76-675 AU]; P=0.49). Similarly, there were no differences in change in peak aortic jet velocity or 18F-sodium fluoride aortic valve uptake. CONCLUSIONS: Neither denosumab nor alendronic acid affected progression of aortic valve calcification in patients with calcific aortic stenosis. Alternative pathways and mechanisms need to be explored to identify disease-modifying therapies for the growing population of patients with this potentially fatal condition. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02132026.


Assuntos
Alendronato/uso terapêutico , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/tratamento farmacológico , Conservadores da Densidade Óssea/uso terapêutico , Denosumab/uso terapêutico , Progressão da Doença , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/metabolismo , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Resultado do Tratamento , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/tratamento farmacológico , Calcificação Vascular/metabolismo
11.
Opt Express ; 30(14): 24565-24578, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-36237008

RESUMO

A helically twisted ring-core hole assisted fiber (HAF) is proposed for an arbitrary higher-order spatial state generation. In usual circular core fibers, HE and EH modes are degenerate and have vector field distributions. We will show the degeneracy of these modes having specific azimuthal mode order is lifted by periodically placing air-holes around the core with specific symmetry while preserving their vector field distributions. It is called spontaneously broken degeneracy (SBD) in this paper. Azimuthal order of the SBD modes can be changed with the arrangement of surrounding air-holes. By using this SBD modes, it is shown that arbitrary higher-order spatial state generation, including orbital angular momentum (OAM) state, is possible based on a geometric phase existing in twisted fibers. Furthermore, by using periodically inverted twisting, efficient OAM state generation is possible by accumulating the geometric phase. The topological charge can be changed by changing the arrangement of surrounding air-holes. Since the mechanism does not depend on a phase matching, such as a long-period grating, but on a topological effect, the wavelength dependence is very small, leading to novel and efficient mechanism for the manipulation of the spatial state of the light.

12.
Opt Express ; 29(20): 31689-31705, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615257

RESUMO

Using orbital angular momentum (OAM) as a spatial information channel attracts a lot of attention due to its infinite multiplexing capability. The research on OAM carrying fibers is intensively studied and ring-core fibers are promising candidates for them. At the same time, generating OAM modes in those fibers are also important topic. Here, the evolutions of polarization states including OAM of light in helically twisted ring-core photonic crystal fibers (PCFs) are investigated for generating OAM states. The degeneracy of some of the mode sets is spontaneously broken, and the birefringence cause a geometric phase (GP) in the twisted PCFs while preserving the vectorial nature of the modes. It is demonstrated that an arbitrary polarization and OAM state can be generated by using the GP in uniformly twisted and twisted PCFs with periodical inversion. In the ring-core PCF presented in this paper, the degeneracy of HE31 and EH31 mode sets are broken, and OAM light with the topological charge of 2 and 4 can be generated. The wavelength dependence is very small compared with that of OAM generators based on long-period gratings (LPGs). Furthermore, by properly setting the period of the inversion, OAM light with different topological charges can be simultaneously generated with the same fiber structure. These results indicate that the proposed approach is effective for the generation of OAM modes with the conventional fiber modes.

13.
Opt Express ; 29(17): 27322-27331, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34615150

RESUMO

We propose a broadband silicon four-mode multi/demultiplexer which consists of three asymmetric directional couplers, and the asymmetric directional couplers were designed by a wavefront matching method to operate as mode multi/demultiplexers for TE1, TE2, and TE3 modes, respectively. Simulated results show that the -0.5-dB bandwidths of normalized transmission of the couplers designed by a wavefront matching method are 112, 114, and 134 nm, respectively. Those for the conventional couplers are 80, 72, 65 nm, respectively. The superiority of asymmetric directional couplers designed by a wavefront matching method are experimentally demonstrated. In the additional investigation, ultrabroadband tapered asymmetric directional couplers are theoretically demonstrated.

14.
Ann Emerg Med ; 77(6): 575-588, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33926756

RESUMO

STUDY OBJECTIVE: To determine whether risk stratification in the out-of-hospital setting could identify patients with chest pain who are at low and high risk to avoid admission or aid direct transfer to cardiac centers. METHODS: Paramedics prospectively enrolled patients with suspected acute coronary syndrome without diagnostic ST-segment elevation on the ECG. The History, ECG, Age and Risk Factors (HEAR) score was recorded contemporaneously, and out-of-hospital samples were obtained to measure cardiac Troponin I (cTnI) level on a point-of-care device, to allow calculation of the History, ECG, Age, Risk Factors, and Troponin (HEART) score. HEAR and HEART scores less than or equal to 3 and greater than or equal to 7 were defined as low and high risk for major adverse cardiac events at 30 days. RESULTS: Of 1,054 patients (64 years [SD 15 years]; 42% women), 284 (27%) experienced a major adverse cardiac event at 30 days. The HEAR score was calculated in all patients, with point-of-care cTnI testing available in 357 (34%). A HEAR score less than or equal to 3 identified 32% of patients (334/1,054) as low risk, with a sensitivity of 84.9% (95% confidence interval [CI] 80.7% to 89%), whereas a score greater than or equal to 7 identified just 3% of patients (30/1,054) as high risk, with a specificity of 98.7% (95% CI 97.9% to 99.5%). A point-of-care HEART score less than or equal to 3 identified a similar proportion as low risk (30%), with a sensitivity of 87.0% (95% CI 80.7% to 93.4%), whereas a score greater than or equal to 7 identified 14% as high risk, with a specificity of 94.8% (95% CI 92.0% to 97.5%). CONCLUSION: Paramedics can use the HEAR score to discriminate risk, but even when used in combination with out-of-hospital point-of-care cTnI testing, the HEART score does not safely rule out major adverse cardiac events, and only a small proportion of patients are identified as high risk.


Assuntos
Ambulâncias , Dor no Peito/diagnóstico , Admissão do Paciente/estatística & dados numéricos , Transferência de Pacientes/estatística & dados numéricos , Medição de Risco/métodos , Idoso , Biomarcadores/sangue , Institutos de Cardiologia/estatística & dados numéricos , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Escócia , Troponina T/sangue
15.
Cardiovasc Drugs Ther ; 35(6): 1281-1290, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33608862

RESUMO

PURPOSE: Endothelial dysfunction is central to the pathogenesis of acute coronary syndrome. The study of diseased endothelium is very challenging due to inherent difficulties in isolating endothelial cells from the coronary vascular bed. We sought to isolate and characterise coronary endothelial cells from patients undergoing thrombectomy for myocardial infarction to develop a patient-specific in vitro model of endothelial dysfunction. METHODS: In a prospective cohort study, 49 patients underwent percutaneous coronary intervention with thrombus aspiration. Specimens were cultured, and coronary endothelial outgrowth (CEO) cells were isolated. CEO cells, endothelial cells isolated from peripheral blood, explanted coronary arteries, and umbilical veins were phenotyped and assessed functionally in vitro and in vivo. RESULTS: CEO cells were obtained from 27/37 (73%) atherothrombotic specimens and gave rise to cells with cobblestone morphology expressing CD146 (94 ± 6%), CD31 (87 ± 14%), and von Willebrand factor (100 ± 1%). Proliferation of CEO cells was impaired compared to both coronary artery and umbilical vein endothelial cells (population doubling time, 2.5 ± 1.0 versus 1.6 ± 0.3 and 1.2 ± 0.3 days, respectively). Cell migration was also reduced compared to umbilical vein endothelial cells (29 ± 20% versus 85±19%). Importantly, unlike control endothelial cells, dysfunctional CEO cells did not incorporate into new vessels or promote angiogenesis in vivo. CONCLUSIONS: CEO cells can be reliably isolated and cultured from thrombectomy specimens in patients with acute coronary syndrome. Compared to controls, patient-derived coronary endothelial cells had impaired capacity to proliferate, migrate, and contribute to angiogenesis. CEO cells could be used to identify novel therapeutic targets to enhance endothelial function and prevent acute coronary syndromes.


Assuntos
Doença das Coronárias/patologia , Células Endoteliais/patologia , Trombose/patologia , Animais , Células Endoteliais da Veia Umbilical Humana , Humanos , Técnicas In Vitro , Camundongos , Trombectomia
16.
Opt Express ; 28(25): 38196-38205, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33379637

RESUMO

A broadband and compact TE0-TE1 mode converter for a mode division multiplexing system designed using a wavefront matching method is realized. We present the first experimental demonstration of a silicon waveguide device designed by a wavefront matching method. In order to achieve broadband operation of the silicon mode converter, seven wavelengths are considered in its optimization process. The designed silicon mode converter is fabricated via a standard complementary metal-oxide-semiconductor technology, which enables low-cost mass production. Measurements performed using the fabricated mode converter correlate strongly with the calculated results.

17.
Opt Express ; 28(7): 9653-9665, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32225568

RESUMO

A general design rule of scrambling-type mode (de)multiplexers (mode scramblers) based on silica planar lightwave circuit (PLC) with small mode-dependent-loss (MDL) is presented for a mode-division multiplexing (MDM) system. First, we consider four- and eight-mode scramblers and demonstrate that if the number of modes is 2N, it is possible to construct small-MDL mode scramblers by using Y-branch waveguides and mode rotators. Next, a 6-mode scrambler, which can be used for four linearly polarized (LP) mode transmission in MDM system, is considered, and the MDL is large if Y-branch waveguides are cascaded simply, originating from the radiation loss of unwanted modes at the Y-branch. We propose a 2 + 4-type mode scrambler by combining 2- and 4-mode scramblers and demonstrate that it is possible to design a small MDL 6-mode scrambler.

18.
Respir Res ; 21(1): 162, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32590988

RESUMO

BACKGROUND: Ischemic heart disease is common in COPD and associated with worse prognosis. This study aimed to investigate the presence and prognostic impact of biomarkers of myocardial injury and ischemia among individuals with COPD and normal lung function, respectively. METHODS: In 2002-04, all individuals with airway obstruction (FEV1/VC < 0.70, n = 993) were identified from population-based cohorts, together with age and sex-matched non-obstructive referents. At re-examination in 2005, spirometry, Minnesota-coded ECG and analyses of high-sensitivity cardiac troponin I (hs-cTnI) were performed in individuals with COPD (n = 601) and those with normal lung function (n = 755). Deaths were recorded until December 31st, 2010. RESULTS: Hs-cTnI concentrations were above the risk stratification threshold of ≥5 ng/L in 31.1 and 24.9% of those with COPD and normal lung function, respectively. Ischemic ECG abnormalities were present in 14.8 and 13.4%, while 7.7 and 6.6% had both elevated hs-cTnI concentrations and ischemic ECG abnormalities. The 5-year cumulative mortality was higher in those with COPD than those with normal lung function (13.6% vs. 7.7%, p < 0.001). Among individuals with COPD, elevated hs-cTnI both independently and in combination with ischemic ECG abnormalities were associated with an increased risk for death (adjusted hazard ratio [HR]; 95% confidence interval [CI] 2.72; 1.46-5.07 and 4.54; 2.25-9.13, respectively). Similar associations were observed also among individuals with COPD without reported ischemic heart disease. CONCLUSIONS: In this study, elevated hs-cTnI concentrations in combination with myocardial ischemia on the electrocardiogram were associated with a more than four-fold increased risk for death in a population-based COPD-cohort, independent of disease severity.


Assuntos
Isquemia Miocárdica/sangue , Isquemia Miocárdica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Troponina I/sangue , Idoso , Biomarcadores/sangue , Estudos de Coortes , Eletrocardiografia/tendências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico , Prognóstico , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Suécia/epidemiologia
19.
Opt Express ; 27(11): 16281-16295, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31163808

RESUMO

We numerically investigate the group delay spread (GDS) characteristics in few-mode coupled multicore fibers (FM-CMCFs) in weak random-bending conditions by using a coupled-wave theory. We qualitatively show the modal coupling between modes in the intra- and the inter-mode group generated by bending. The results indicate that the modes of FM-CMCFs are less likely to couple with each other in weak random-bending conditions in contradiction to single-mode coupled multicore fibers. To resolve this problem, we demonstrate an optimum index profile and core pitch, where the GDS can be reduced even if the different mode groups do not couple strongly.

20.
Opt Express ; 27(25): 36286-36296, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31873411

RESUMO

A novel Si four-wavelength multiplexer (MUX) for 100/400GbE composed of (a)symmetric directional couplers and a rib-waveguide TE1-TM0 mode converter is proposed and experimentally demonstrated. Two-lane signals are multiplexed as TE0 modes via symmetric directional coupler (DC) and other two-lane signals are multiplexed as TE1 modes via asymmetric directional couplers (ADCs). Finally, TE1 modes are converted to TM0 modes and the device acts as a 4-lane MUX. The proposed device is fabrication-tolerant due to the removal of the 1600-GHz filter used in conventional two-stage Mach-Zehnder MUXs, and the insertion loss is smaller than those of previously reported Si-based MUXs.

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