[Troponin-T and n-terminal pro-brain type natriuretic peptide plasma levels and its relationship with mortality in COVID-19]. / Niveles plasmáticos de troponina T y de la fracción aminoterminal del propéptido natriurético cerebral y su relación con mortalidad en COVID-19.

INTRODUCTION: Cardiovascular compromise in coronavirus disease 2019 (COVID-19) does not necessarily present with the classic symptoms described in myocarditis. There is growing evidence demonstrating subclinical cardiovascular compromise in the context of the intense inflammation unleashed, the cytokine storm involved, the baseline prothrombotic state, and the consequent endothelial dysfunction. We set out to analyse whether Troponin-T (TT) and the amino-terminal fraction of pro-brain natriuretic peptide (NT-proBNP) determined at hospital admission, are related to mortality during the hospitalization of these patients. MATERIAL AND METHODS: Analytical, observational, retrospective cohort and cross-sectional study. It included subjects with COVID-19 hospitalized for moderate-severe illness, from 20/03/20 to 15/11/20. The TT and NT-proBNP obtained in the first 24 hours from admission were analysed. Altered TT was considered if ≥.014 ng/dl and altered NT-proBNP if ≥300 pg/ml. RESULTS: One hundred and eight subjects were included, 63.2% men, age 51.5 years (59-43), 28% were admitted to the Critical Unit and 25% died. The group with elevated TT presented higher mortality (OR = 3.1; 95%CI = 1.10-8.85; p = .02). The group with elevated NT-proBNP also show higher mortality (OR = 3.47; 95%CI = 1.21-9.97; p = .01). On multivariate analysis, only NT-proBNP ≥300 pg/ml remained an independent risk factor. CONCLUSIONS: NT-proBNP levels ≥300 pg/ml at admission in patients with moderate-severe COVID-19 were associated with higher mortality.

Desempenho Diagnóstico da Angiotomografia Computadorizada e da Avaliação Seriada de Troponina Cardíaca Sensível em Pacientes com Dor Torácica e Risco Intermediário para Eventos Cardiovasculares / Diagnostic Performance of Coronary Tomography Angiography and Serial Measurements of Sensitive Cardiac Troponin in Patients With Chest Pain and Intermediate Risk for Cardiovascular Events

Resumo Fundamento A angiotomografia coronária (ATC) tem sido usada para avaliação de dor torácica principalmente em pacientes de baixo risco, e poucos dados existem com pacientes em risco intermediário. Objetivo Avaliar o desempenho de medidas seriadas de troponinas sensíveis e de ATC em pacientes de risco intermediário. Métodos Um total de 100 pacientes com dor torácica, TIMI score 3 ou 4 e troponina negativa foram prospectivamente incluídos. Todos os pacientes foram submetidos à ATC, e aqueles com obstruções ≥ 50% foram encaminhados à cineangiocoronariografia. Pacientes com lesões < 50% recebiam alta hospitalar, receberam alta e foram contatados 30 dias depois por telefonema para avaliação dos desfechos clínicos. Os desfechos foram hospitalização, morte, e infarto agudo do miocárdio em 30 dias. A comparação entre os métodos foi realizada pelo teste de concordância kappa. O desempenho das medidas de troponina e da ATC na detecção de lesões coronárias significativas e desfechos clínicos foi calculado. Os resultados foram considerados estatisticamente significativos quando p <0,05. Resultados Estenose coronária ≥ 50% na ATC foi encontrada em 38% dos pacientes e lesões coronárias significativas na angiografia coronária foram encontradas em 31 pacientes. Dois eventos clínicos foram observados. A análise de concordância Kappa mostrou baixa concordância entre as medidas de troponina e ATC na detecção de lesões coronárias significativas (kappa = 0,022, p = 0,78). O desempenho da ATC para detectar lesões coronárias significativas na angiografia coronária ou para prever eventos clínicos em 30 dias foi melhor que as medidas de troponina sensível (acurácia de 91% versus 60%). Conclusão ATC teve melhor desempenho que as medidas seriadas de troponina na detecção de doença coronariana significativa em pacientes com dor torácica e risco intermediário para eventos cardiovasculares.

Abstract Background Coronary tomography angiography (CTA) has been mainly used for chest pain evaluation in low-risk patients, and few data exist regarding patients at intermediate risk. Objective To evaluate the performance of serial measures of sensitive troponin and CTA in intermediate-risk patients. Methods A total of 100 patients with chest pain, TIMI risk scores of 3 or 4, and negative troponin were prospectively included. All patients underwent CTA and those with coronary stenosis ≥ 50% were referred to invasive coronary angiography. Patients with coronary lesions <50% were discharged and contacted 30 days later by a telephone call to assess clinical outcomes. Outcomes were hospitalization, death, and myocardial infarction at 30 days. The comparison between methods was performed by Kappa agreement test. The performance of troponin measures and CTA for detecting significant coronary lesions and clinical outcomes was calculated. Results were considered statistically significant when p < 0.05. Results Coronary stenosis ≥ 50% on CTA was found in 38% of patients and significant coronary lesions on coronary angiography were found in 31 patients. Two clinical events were observed. Kappa agreement analysis showed low agreement between troponin measures and CTA in the detection of significant coronary lesions (kappa = 0.022, p = 0.78). The performance of CTA for detecting significant coronary lesions on coronary angiography or for predicting clinical events at 30 days was better than sensitive troponin measures (accuracy of 91% versus 60%). Conclusion CTA performed better than sensitive troponin measures in the detection of significant coronary disease in patients with chest pain and intermediate risk for cardiovascular events.

Markers of myocardial injury in the prediction of short-term COVID-19 prognosis.

INTRODUCTION AND OBJECTIVES: COVID-19 is currently causing high mortality and morbidity worldwide. Information on cardiac injury is scarce. We aimed to evaluate cardiovascular damage in patients with COVID-19 and determine the correlation of high-sensitivity cardiac-specific troponin T (hs-cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) with the severity of COVID-19. METHODS: We included 872 consecutive patients with confirmed COVID-19 from February to April 2020. We tested 651 patients for high-sensitivity troponin T (hs-TnT) and 506 for NT-proBNP on admission. Cardiac injury was defined as hs-TnT> 14ng/L, the upper 99th percentile. Levels of NT-proBNP> 300 pg/mL were considered related to some extent of cardiac injury. The primary composite endpoint was 30-day mortality or mechanical ventilation (MV). RESULTS: Cardiac injury by hs-TnT was observed in 34.6% of our COVID-19 patients. Mortality or MV were higher in cardiac injury than noncardiac injury patients (39.1% vs 9.1%). Hs-TnT and NT-proBNP levels were independent predictors of death or MV (HR, 2.18; 95%CI, 1.23-3.83 and 1.87 (95%CI, 1.05-3.36), respectively) and of mortality alone (HR, 2.91; 95%CI, 1.211-7.04 and 5.47; 95%CI, 2.10-14.26, respectively). NT-ProBNP significantly improved the troponin model discrimination of mortality or MV (C-index 0.83 to 0.84), and of mortality alone (C-index 0.85 to 0.87). CONCLUSIONS: Myocardial injury measured at admission was a common finding in patients with COVID-19. It reliably predicted the occurrence of mortality and need of MV, the most severe complications of the disease. NT-proBNP improved the prognostic accuracy of hs-TnT.

Valor Prognóstico da Troponina T e do Peptídeo Natriurético Tipo B em Pacientes Internados por COVID-19 / Prognostic Value of Troponin-T and B-Type Natriuretic Peptide in Patients Hospitalized for COVID-19

Resumo Fundamento: A COVID-19 causa grave acometimento pulmonar, porém o sistema cardiovascular também pode ser afetado por miocardite, insuficiência cardíaca e choque. A elevação de biomarcadores cardíacos tem sido associada a um pior prognóstico. Objetivos: Avaliar o valor prognóstico da Troponina T (TnT) e do peptídeo natriurético tipo B (BNP) em pacientes internados por Covid-19. Métodos: Amostra de conveniência de pacientes hospitalizados por COVID-19. Foram coletados dados dos prontuários com o objetivo de avaliar a relação da TnT e o BNP medidos nas primeiras 24h de admissão com o desfecho combinado (DC) óbito ou necessidade de ventilação mecânica. Análise univariada comparou os grupos com e sem DC. Modelo multivariado de Cox foi utilizada para determinar preditores independentes do DC. Resultados: Avaliamos 183 pacientes (idade=66,8±17 anos, sendo 65,6% do sexo masculino). Tempo de acompanhamento foi de 7 dias (1 a 39 dias). O DC ocorreu em 24% dos pacientes. As medianas de TnT e BNP foram 0,011 e 0,041 ng/dl (p<0,001); 64 e 198 pg/dl (p<0,001) respectivamente para os grupos sem e com DC. Na análise univariada, além de TnT e BNP, idade, presença de doença coronariana, saturação de oxigênio, linfócitos, dímero-D, proteína C reativa titulada (PCR-t) e creatinina, foram diferentes entre os grupos com e sem desfechos. Na análise multivariada boostraped apenas TnT (1,12[IC95%1,03-1,47]) e PCR-t (1,04[IC95%1,00-1,10]) foram preditores independentes do DC. Conclusão: Nas primeiras 24h de admissão, TnT, mas não o BNP, foi marcador independente de mortalidade ou necessidade de ventilação mecânica invasiva. Este dado reforça ainda mais a importância clínica do acometimento cardíaco da COVID-19. (AArq Bras Cardiol. 2020; 115(4):660-666)

Abstract Background: COVID-19 causes severe pulmonary involvement, but the cardiovascular system can also be affected by myocarditis, heart failure and shock. The increase in cardiac biomarkers has been associated with a worse prognosis. Objectives: To evaluate the prognostic value of Troponin-T (TNT) and natriuretic peptide (BNP) in patients hospitalized for Covid-19. Methods: This was a convenience sample of patients hospitalized for COVID-19. Data were collected from medical records to assess the association of TnT and BNP measured in the first 24 hours of hospital admission with the combined outcome (CO) of death or need for mechanical ventilation. Univariate analysis was used to compare the groups with and without the CO. Cox's multivariate model was used to determine independent predictors of the CO. Results: We evaluated 183 patients (age = 66.8±17 years, 65.6% of which were males). The time of follow-up was 7 days (range 1 to 39 days). The CO occurred in 24% of the patients. The median troponin-T and BNP levels were 0.011 and 0.041ng/dL (p <0.001); 64 and 198 pg/dL (p <0.001), respectively, for the groups without and with the CO. In the univariate analysis, in addition to TnT and BNP, age, presence of coronary disease, oxygen saturation, lymphocytes, D-dimer, t-CRP and creatinine, were different between groups with and without outcomes. In the bootstrap multivariate analysis, only TnT (1.12 [95% CI 1.03-1.47]) and t-CRP (1.04 [95% CI 1.00-1.10]) were independent predictors of the CO. Conclusion: In the first 24h of admission, TnT, but not BNP, was an independent marker of mortality or need for invasive mechanical ventilation. This finding further reinforces the clinical importance of cardiac involvement in COVID-19. (Arq Bras Cardiol. 2020; 115(4):660-666)

Função Diastólica e Biomarcadores de Participantes de Caminhada de Longa Distância / Diastolic Function and Biomarkers of Long-Distance Walking Participants

Resumo Fundamento: Os efeitos da caminhada de longa distância sobre o sistema cardiovascular são pouco estudados. Objetivos: O objetivo geral deste estudo foi verificar esses efeitos sobre o comportamento da função diastólica e dos biomarcadores cardíacos CK-MB (massa), troponina T e NT-proBNP em atletas amadores. Método: Este estudo longitudinal realizado em 2015 avaliou os participantes nas 5 etapas seguintes: A0 (basal) antes de iniciar o percurso, e as demais, A1, A2, A3 e A4 ao final de cada dia, totalizando 244,7 km. Em todas as etapas foram dosados os biomarcadores NT-proBNP, CK-MB (massa) e troponina T. Realizou-se ecocardiograma para análise das ondas E, A e E'. Adotado p < 0,05 como significativo. Resultados: Foram avaliados 25 participantes com média de idade de 46 ± 10,5 anos e índice de massa corporal de 20,2 ± 2,3 kg/m2. Encontrou-se aumentos dos valores de NT-proBNP de A0 para A1, A2, A3 e A4 (p < 0,001), CK-MB (massa) de A0 para A2 (p < 0,001) e da onda E' de A0 para A1, A2, A3 e A4 (p < 0,001). Foram identificadas correlações entre os seguintes: CK-MB (massa) e troponina T (A1: r = 0,524, p = 0,010; A4: r = 0,413, p = 0,044); CK-MB (massa) e NT-proBNP (A4: r = 0,539, p = 0,006); e E/A e E' (A0: r = 0,603, p < 0,001; A1: r = 0,639, p < 0,001; A4: r = 0,593, p = 0,002); e correlação negativa entre CK-MB (massa) com E/A (A1: r = −0,428, p = 0,041). Conclusão: Os efeitos da atividade física intensa, prolongada e intercalada foram verificados a partir das variações significativas no comportamento da CK-MB (massa), NT-proBNP e E'. Apesar das alterações encontradas, não houve critérios sugestivos de dano ao miocárdio.

Abstract Background: The effects of long-distance walking on the cardiovascular system have been little studied. Objectives: The general objective of this study was to verify these effects on the behavior of diastolic function and the cardiac biomarkers CK-MB (mass), troponin T, and NT-proBNP, in amateur athletes. Method: This longitudinal study, conducted in 2015, evaluated participants during the following 5 stages: E0 (baseline) before starting the trajectory and the others, E1, E2, E3, and E4, at the end of each day, totaling 244.7 km. At all stages, the biomarkers NT-proBNP, CK-MB (mass), and troponin T were measured. Echocardiogram was performed to analyze the E, A and E' waves. P < 0.05 was adopted as significant. Results: The study evaluated 25 participants, with an average age of 46 ± 10.5 years and body mass index of 20.2 ± 2.3 kg/m2. Increased values were found for NT-proBNP from E0 to E1, E2, E3, and E4 (p < 0.001), CK-MB (mass) from E0 to E2 (p < 0.001), and E' wave from E0 to E1, E2, E3, and E4 (p < 0.001). Positive correlations were identified between the following: CK-MB (mass) and troponin T (E1: r = 0.524, p = 0.010; E4: r = 0.413, p = 0.044); CK-MB (mass) and NT-proBNP (E4: r = 0.539, p = 0.006); and E/A and E' (E0: r = 0.603, p < 0.001; E1: r = 0.639, p < 0.001; E4: r = 0.593, p = 0.002). A negative correlation was found between CK-MB (mass) and E/A (E1: r = −0.428, p = 0.041). Conclusion: The effects of intense, prolonged, and interspersed physical activity were verified based on significant variations in the behavior of CK-MB (mass), NT-proBNP, and the E' wave. Notwithstanding the alterations found, there were no criteria suggestive of myocardial damage

Lo mejor del Congreso Uruguayo de Cardiología 2018 / The best of the 2018 Uruguayan Congress of Cardiology / O melhor do Congresso Uruguaio de Cardiologia 2018

Resumen: El 34° Congreso Uruguayo de Cardiología, celebrado en Montevideo del 2 al 4 de diciembre del pasado año, nuevamente destacó por las excelentes presentaciones de los temas más relevantes del ámbito cardiológico, así como también por sus invitados de renombre, nacionales e internacionales. Acompañando el gran nivel del Congreso se expusieron 32 temas libres que abarcaron diferentes áreas de la cardiología de los cuales comentaremos cuatro trabajos premiados: - Riesgo de trombosis en bioprótesis aórtica y eventos clínicos según uso de anticoagulación. Metaanálisis de la evidencia actual. - Uso de NT-ProBNP como predictor de evolución en el posoperatorio de cirugía cardíaca. - Prevalencia de septal pouch en una cohorte derivada para ecocardiograma transesofágico. - Incidencia de troponina T ultrasensible en rango anormal y su correlación con la anatomía coronaria en pacientes en valoración por enfermedad coronaria estable.

Summary: The 34th Uruguayan Congress of Cardiology, celebrated last year in Montevideo from December 2nd to 4th, again stood out for the excellent presentations of the most relevant topics in the field of cardiology, as well as for its renowned national and international guests. Accompanying the great level of the Congress, 32 articles that covered different topics in the cardiological area were presented, of which we will comment four awarded: - Risk of thrombosis in aortic bioprosthesis and clinical events according to the use of anticoagulation. Meta-analysis of current evidence. - Use of NT-ProBNP as a predictor of evolution in the postoperative period of cardiac surgery. - Prevalence of septal pouch in a cohort derived for transesophageal echocardiography. - Incidence of ultrasensitive troponin T in abnormal range and its correlation with coronary anatomy in patients in assessment for stable coronary disease.

Resumo: O 34º Congresso Uruguaio de Cardiologia, realizado em Montevidéu entre os dias 2 e 4 de dezembro no ano passado, voltou a destacar-se pelas excelentes apresentações dos temas mais relevantes no campo da cardiologia, bem como por seus renomados convidados, nacionais e internacionais. Acompanhando o grande nível do Congresso, tinham 32 temas livres que cobriam diferentes áreas da cardiologia, dos quais comentaremos quatro artigos premiados: - Risco de trombose na bioprótese aórtica e eventos clínicos de acordo com o uso de anticoagulação. Meta-análise da evidência atual. - Uso de NT-ProBNP como preditor de evolução no pós-operatório de cirurgia cardíaca. - Prevalência de bolsa septal em uma coorte derivada para ecocardiografia transesofágica. - Incidência de troponina T ultrassensível em faixa anormal e sua correlação com a anatomia coronariana em pacientes em avaliação para doença coronariana estável.

Desafios na interpretação dos ensaios de troponina ultrassensível em terapia intensiva / Challenges in high-sensitive troponin assay interpretation for intensive therapy

RESUMO As troponinas cardíacas T e I são marcadores considerados altamente sensíveis e específicos para o diagnóstico de infarto agudo do miocárdio. Atualmente, com o advento dos ensaios ultrassensíveis, uma série de anormalidades não primariamente cardíacas pode se manifestar por meio da elevação destes ensaios. A redução de seu limiar de detecção promoveu maior precocidade no diagnóstico e na utilização de medidas terapêuticas baseadas em evidência, no entanto, esta característica aumentou o espectro de doenças cardíacas não coronarianas detectáveis, trazendo desafios para a caracterização das síndromes coronarianas agudas e um novo papel para estes testes nas desordens conhecidas no ambiente das unidades de tratamento intensivo, em especial na sepse. A abordagem de pacientes por meio de um maior entendimento do comportamento destes marcadores deve ser redimensionada para sua correta interpretação.

ABSTRACT Cardiac troponins T and I are considered highly sensitive and specific markers for the diagnosis of acute myocardial infarction. Currently, a series of nonprimary cardiac abnormalities may manifest as an elevation in high-sensitive assays. The reduction in their detection limits has allowed earlier diagnosis and the use of evidence-based therapeutic measures; however, this characteristic has increased the spectrum of detectable noncoronary heart diseases, which poses challenges for characterizing acute coronary syndromes and creates a new role for these tests in known disorders in intensive care units, especially sepsis. Management of patients through a greater understanding of how these markers behave should be re-evaluated to ensure their correct interpretation.

Utilidad del score HEART con troponina T de alta sensibilidad para la evaluación de pacientes con dolor torácico / Usefulness of the HEART Score with High-Sensitivity Troponin T for the Evaluation of Patients withChest Pain

RESUMEN Introducción: El score HEART consiste en una prueba sencilla que fue diseñada para estratificar a los pacientes que consultan al servicio de emergencias por dolor torácico, según su riesgo de presentar un síndrome coronario agudo a corto plazo. Fue creado inicialmente con troponina de cuarta generación, pero el advenimiento de la troponina de alta sensibilidad impuso su incorporación al score y la reevaluación de su comportamiento. Objetivo: Nos propusimos evaluar el comportamiento del score HEART con troponina de alta sensibilidad. Material y métodos: Se realizó un estudio prospectivo que incluyó 1464 pacientes (p) que consultaron al servicio de emergencia por dolor torácico y que tenían electrocardiograma sin elevación del segmento ST. Se evaluó la incidencia de MACE (combinado de infarto agudo de miocardio, muerte y revascularización) a 30 días. Resultados: El índice clasificó 739 pacientes (50,5 %) como de bajo riesgo, 515 pacientes (35,2%) de riesgo intermedio y 210 pacientes (14,3%) de alto riesgo. La incidencia de la combinación de infarto agudo de miocardio, muerte y revascularización fue del 1,35% en el primer grupo; del 20%, en el segundo; y del 71%, en el tercero (long rank test p < 0,001). El área bajo la curva global para la combinación de infarto agudo de miocardio, muerte y revascularización fue de 0,91 (0,89-0,93). Conclusiones: El score HEART que utiliza troponina de alta sensibilidad tiene una gran capacidad para clasificar pacientes con dolor torácico de acuerdo con su riesgo de presentar eventos cardiovasculares en el corto plazo.

Caracterización de los pacientes con diagnóstico presuntivo de síndrome coronario agudo sin elevación del segmento ST que asisten a un servicio de urgencias / Profile of patients with non-ST elevation acute coronary syndrome that attend an Emergency Department

Resumen El dolor torácico es uno de los principales motivos de consulta al sistema de urgencias, y este es secundario a condiciones como el síndrome coronario agudo entre otras. Para su diagnóstico se requiere no sólo el resultado de la troponina, sino una evaluación clínica completa en la que se tengan en cuenta factores de riesgo cardiovascular, características del dolor y hallazgos electrocardiográficos. La interpretación inadecuada de las troponinas ultrasensibles lleva a que se someta al paciente a riesgos innecesarios a causa de estudios como el cateterismo cardiaco. Se llevó a cabo un estudio de corte trasversal en un hospital de Bogotá, en el que la causa principal de consulta en el servicio de urgencias fue el dolor torácico, y la primera causa de hospitalización en Cardiología el síndrome coronario agudo. Se recolectaron datos de 411 pacientes a quienes se les realizó arteriografía coronaria, la mayoría hombres con factores de riesgo como hipertensión arterial, tabaquismo y un evento coronario previo. Dentro de los estudios paraclínicos, la fracción de eyección promedio estuvo cercana al 50% y sólo en 201 pacientes se encontraron lesiones epicárdicas significativas.De la muestra analizada, el 13% tenía creatinina mayor de 1,5 mg/dl como causa alterna de elevación del biomarcador y 28% tenía disfunción ventricular izquierda de algún grado. La mayoría de los pacientes en quienes no se documentaron lesiones angiográficamente significativas en el cateterismo cardiaco, la troponina no cumplía criterios de positividad con base en el aumento del 20% respecto al valor inicial si este era positivo o de 50% en caso de que el primer valor fuese negativo. Adicionalmente, del grupo de pacientes con enfermedad coronaria angiográficamente significativa fue más frecuente la combinación de tres o más factores de riesgo cardiovascular en presencia de biomarcador positivo.

Abstract Chest pain is one of the main reasons for consulting the Emergency Department, and it is secondary to conditions, such as acute coronary syndrome. For its diagnosis, it not only requires a Troponin result, but also a full clinical evaluation, in which factors like cardiovascular risk have to be taken into account, as well as characteristics of the pain and the findings on the electrocardiogram. The poor interpretation of the ultrasensitive Troponins leads to the patient being subjected to unnecessary risks due to studies such as cardiac catheterisation. A cross-sectional study was conducted in a hospital in Bogota, in which chest pain was the main reason for consulting the Emergency Department, and acute coronary syndrome the first cause of admission to Cardiology. The study included a total of 411 patients on whom a coronary angiography was performed. The majority were males with risk factors such as arterial hypertension, smokers, and with a previous coronary event. Among the para-clinical studies, the mean ejection fraction was around 50%, and significant epicardial lesions were found in only 201 patients.Of the sample analysed, 13% had a creatinine greater than 1.5 mg/dl as an alternative cause of the elevation of the biomarker, and 28% had some degree of left ventricular function. the majority of patients that did not have significant angiographic lesions in the cardiac catheterisation documented, the Troponin did not meet the criteria for being positive, based on an increase of 20% as regards the initial value if this was positive or 50% in the case where the first value was negative. Furthermore, of the patient group with significant angiographic coronary disease, the combination of three or more cardiovascular risk factors was the most frequent in the presence of a positive biomarker.

A bioquímica clínica no diagnóstico e prognóstico de pacientes acometidos pelo Infarto Agudo do Miocárdio evidenciando a importância da Troponina T / The clinical biochemistry in the diagnosis and prognosis of patients affected by acute myocardial infarction evidencing the importance of Troponina T

Introdução: o Infarto Agudo do Miocárdio (IAM) é a mais importante e frequente cardiopatia isquêmica ocasionada por necrose do músculo cardíaco (miocárdio) em consequência de isquemia prolongada, sendo mais frequente em adultos e idosos. O diagnóstico é baseado no quadro clínico, alterações eletrocardiográficas e resultados de exames de sangue com elevação dos marcadores bioquímicos de necrose miocárdica: Troponina T, CKMB (creatina-quinase-fraçãoMB) e CK (creatina-quinase-total) que são liberadas pelas células assim que o suprimento de sangue fica bloqueado, sendo a Troponina o principal marcador por estar presente na estrutura do músculo cardíaco. A bioquímica clínica desempenha papel fundamental no diagnóstico laboratorial do IAM, pois as dosagens devem ser analisadas rapidamente para melhor prognóstico, eficácia do tratamento e sobrevida do paciente. Embasados na alta prevalência das doenças cardiovasculares, no envelhecimento populacional e na importância do diagnóstico laboratorial. O objetivo desta revisão bibliográfica foi descrever a importância dos principais marcadores bioquímicos quanto à sensibilidade e especificidade com ênfase para a Troponina T. Trata-se de um estudo transversal descritivo por revisão da literatura de artigos científicos completos, capítulos de livros, dissertações e teses nos idiomas português e inglês, nas bases de dados SCIELO, LILACS, BIREME, BIBLIOTECA VIRTUAL DE SAÚDE. Após a revisão, evidencia-se a importância da emergência médica com o diagnóstico laboratorial preciso e confiável da Troponina T que é liberada em 3 horas após o IAM e que pode ser dosada por imunocromatografia ou quantitativamente, e deve estar inserida na rotina dos laboratórios privados e hospitalares para melhor qualidade de vida do paciente.

Introduction: acute Myocardial Infarction (AMI) is the most important and frequent ischemic heart disease caused by cardiac (myocardial) muscle necrosis as a consequence of prolonged ischemia, being more frequent in adults and the elderly. The diagnosis is based on the clinical picture, electrocardiographic changes and results of blood tests with elevation of biochemical markers of myocardial necrosis: Troponin T, CKMB (creatine kinase-MB fraction) and CK (creatine kinase-total) that are released by the cells as soon as the blood supply is blocked, Troponin being the main marker because it is present in the structure of the heart muscle. Clinical biochemistry plays a fundamental role in the laboratory diagnosis of AMI, since the dosages should be analyzed quickly for better prognosis, treatment efficacy and patient survival. Based on the high prevalence of cardiovascular diseases, population aging and the importance of laboratory diagnosis, the objective of this literature review was to describe the importance of the main biochemical markers for sensitivity and specificity with emphasis on Troponin T. This is a cross-sectional study descriptive literature review of complete scientific articles, book chapters, dissertations and theses in the Portuguese and English languages, in the databases SCIELO, LILACS, BIREME, VIRTUAL HEALTH LIBRARY. After the review, the importance of the medical emergency with the accurate and reliable laboratory diagnosis of Troponin T, which is released within 3 hours after AMI and can be quantified by immunochromatography or quantitatively, should be included in the routine of the private and the quality of life of the patient.

Right ventricular dysfunction in acute pulmonary embolism: NT-proBNP vs. troponin T. / Disfunción del ventrículo derecho en la embolia pulmonar aguda: NT-proBNP frente a troponina T.

BACKGROUND AND OBJECTIVE: Dysfunction of the right ventricle (RV) is a parameter of severity in acute pulmonary embolism (PE). Echocardiographic assessment is not always possible in accident and emergency, hence the need to predict the presence of RV dysfunction using easily measurable parameters. To analyse the value of NT-proBNP and troponin T as markers of RV dysfunction in patients with acute PE. Secondarily, to assess the relationship between RV failure and clinical parameters related to PE. MATERIAL AND METHOD: Analytical, observational, cross-sectional and retrospective study comparing the values NT-proBNP, troponin T and presenting symptoms of PE among patients with and without RV dysfunction. RESULTS: One hundred seventy-two patients (52 with RV failure,120 without) were included. All symptoms occurred with similar frequency between the 2groups except dyspnea and syncope (more common in the group with RV failure). Both NT-proBNP and troponin T had significantly higher values in the group of patients with RV dysfunction. However, in the multivariate analysis, NT-proBNP had a higher explanatory value for RV failure than troponin T. CONCLUSION: NT-proBNP is a diagnostic parameter of RV dysfunction with higher sensitivity in the context of acute PE.

High-sensitivity Troponin T Assay in Asymptomatic High Cardiovascular Risk Patients. The TUSARC Registry.

INTRODUCTION AND OBJECTIVES: High-sensitivity troponin T assays (Hs-TnT) have been carried out in selected populations in clinical trials and in registries of the general population with low cardiovascular risk (CVR). The aim of this study was to determine the proportion of individuals with detectable Hs-TnT and the proportion of individuals with elevated Hs-TnT in a Spanish population of asymptomatic individuals with very high CVR, as well as the parameters associated with Hs-TnT elevation. METHODS: The study included 690 patients. Hs-TnT detection and Hs-TnT elevation (≥99th percentile value), as well the association of elevated Hs-TnT and clinical, analytical, and treatment data were analyzed. RESULTS: Hs-TnT was analyzed in 646 patients and was detected in 645. Elevated TnT was detected in 212 patients (32.9%). On multivariate analysis, elevated TnT was independently associated with male sex (OR, 2.81; 95%CI, 1.67-4.73; P < .001), older age (OR, 1.06; 95%CI, 1.04-1.09; P < .001), a higher body mass index (OR, 1.07; 95%CI, 1.02-1.12; P < .002), insulin therapy (OR, 1.99; 95%CI, 1.15-3.46; P = .01), history of heart failure (OR, 3.92; 95%CI, 1.24-12.39; P = .02), and estimated glomerular filtration rate calculated by CKD-EPI (OR, 0.96; 95%CI, 0.95-0.97; P < .001). CONCLUSIONS: In a Spanish population of asymptomatic individuals at very high CVR, Hs-TnT was associated with older age, male sex, higher body mass index, insulin therapy, history of heart failure, and lower glomerular filtration rate.

Serial High-Sensitivity Troponin T in Post-Primary Angioplasty Exercise Test / Troponina T de Alta Sensibilidade Seriada em Teste de Estresse Realizado Após Angioplastia Primária

Abstract Background: The kinetics of high-sensitivity troponin T (hscTnT) release should be studied in different situations, including functional tests with transient ischemic abnormalities. Objective: To evaluate the release of hscTnT by serial measurements after exercise testing (ET), and to correlate hscTnT elevations with abnormalities suggestive of ischemia. Methods: Patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing primary angioplasty were referred for ET 3 months after infarction. Blood samples were collected to measure basal hscTnT immediately before (TnT0h), 2 (TnT2h), 5 (TnT5h), and 8 hours (TnT8h) after ET. The outcomes were peak hscTnT, TnT5h/TnT0h ratio, and the area under the blood concentration-time curve (AUC) for hscTnT levels. Log-transformation was performed on hscTnT values, and comparisons were assessed with the geometric mean ratio, along with their 95% confidence intervals. Statistical significance was assessed by analysis of covariance with no adjustment, and then, adjusted for TnT0h, age and sex, followed by additional variables (metabolic equivalents, maximum heart rate achieved, anterior wall STEMI, and creatinine clearance). Results: This study included 95 patients. The highest geometric means were observed at 5 hours (TnT5h). After adjustments, peak hscTnT, TnT5h/TnT0h and AUC were 59% (p = 0.002), 59% (p = 0.003) and 45% (p = 0.003) higher, respectively, in patients with an abnormal ET as compared to those with normal tests. Conclusion: Higher elevations of hscTnT may occur after an abnormal ET as compared to a normal ET in patients with STEMI.

Resumo Fundamento: O comportamento da troponina T de alta sensibilidade (hscTnT) deve ser estudado em diversas situações, incluindo testes funcionais com alterações sugestivas de isquemia transitória. Objetivo: Analisar o comportamento da hscTnT seriada após teste ergométrico (TE) e correlacionar aumentos desse marcador com anormalidades sugestivas de isquemia. Métodos: Participantes com infarto agudo do miocárdio com supradesnível do segmento ST (IAMCSST) submetidos à angioplastia primária e encaminhados para TE realizado após terceiro mês do infarto. A hscTnT foi coletada imediatamente antes do exame (TnT0h) e 2 (TnT2h), 5 (TnT5h) e 8 horas (TnT8h) após (TnT0h, TnT2h, TnT5h e TnT8h, respectivamente). Os desfechos considerados foram: pico de hscTnT (TnT pico), razão TnT5h/TnT0h e área sob a curva. Utilizada transformação logarítmica e apresentação dos valores como médias geométricas. As comparações foram sumarizadas pela razão das médias com seus respectivos intervalos de confiança. A significância estatística foi verificada em modelo de ANCOVA sem ajustes e, em seguida, ajustando-se para a TnT0h, sexo, idade e variáveis adicionais (METS, porcentagem da frequência cardíaca máxima atingida, IAMCSST de parede anterior e depuração da creatinina). Resultados: Foram incluídos 95 participantes. Ocorreram maiores valores nas médias geométricas de hscTnT no momento de TnT5h. Após ajustes, o TnT pico, TnT5h/TnT0h e área sob a curva foram 59% (p = 0,002), 59% (p = 0,003) e 45% (p = 0,003) maiores, respectivamente, em pacientes apresentando TE alterado em comparação a TE normal. Conclusão: Maiores elevações de hscTnT podem ocorrer após TE alterado em comparação a testes normais em pacientes com histórico de IAMCSST.

[High-sensitivity troponin T testing and coronary computed tomography angiography for rapid diagnosis of chest pain in the emergency department]. / Troponina T de alta sensibilidad y angiotomografía computarizada coronaria para el diagnóstico rápido del dolor torácico en el servicio de urgencias.

OBJECTIVES: To determine the probability of finding significant coronary lesions, the time to diagnosis, and the safety of a new diagnostic approach based on high-sensitivity cardiac troponin T (hsTnT) testing followed by coronary computed tomography angiography (CCTA) in patients with chest pain of possible coronary origin. The method was compared with our hospital emergency department's standard practice. MATERIAL AND METHODS: Unblinded randomized controlled trial in a tertiary level university hospital between February 2011 and April 2013. We included emergency patients with chest pain and nondiagnostic electrocardiographic findings. Patients were assigned randomly to the new approach (hsTnT assay, followed by CCTA if the assay findings were negative) or the conventional approach (fourth generation TnT assay and, if negative, followed by an exercise stress test). Invasive coronary angiography was ordered in all patients if the results of either troponin assay, the CCTA, or the stress test were positive. We recorded the results of angiography, time until diagnosis, and all-cause mortality, new myocardial infarction, new unstable angina, or need for revascularization within the next 3 months. RESULTS: Of 102 patients randomized, 7 were excluded; 50 of the remaining 95 patients were assigned to the new strategy, and 45 to the conventional approach. Coronary angiography demonstrated significant lesions in 92.9% of the patients treated with the new strategy and 66.7% of those diagnosed conventionally. A higher percentage of patients were diagnosed within 6 hours with the new approach (20.0% vs 4.4% of conventional-approach patients, P = .023). During the 3 months following diagnosis, 1 death occurred in the intervention group and none in the conventional-approach group. CONCLUSION: The new strategy could accelerate diagnosis and increase the probability of finding significant coronary lesions, but we found no significant differences in adverse events in the 3 months following diagnosis. These findings should be confirmed in studies with larger numbers of patients.

OBJETIVO: Determinar la probabilidad de encontrar lesiones coronarias significativas, el tiempo diagnóstico y la seguridad de una nueva estrategia basada en la utilización de troponina T de alta sensibilidad (TnT-as) seguida de angiotomografía computarizada coronaria (ATCC) en pacientes con dolor torácico de posible origen coronario, en comparación con la atención clínica habitual en un servicio de urgencias (SU). METODO: Ensayo clínico diagnóstico aleatorizado y abierto realizado en un SU de un hospital terciario universitario entre febrero 2011 y abril 2013. Se incluyó a pacientes atendidos por dolor torácico con electrocardiograma no diagnóstico en urgencias. Se asignó de forma aleatorizada a la estrategia nueva (EN) (seriación de TnT-as seguida de ATCC cuando fue negativa) o la estrategia convencional (EC) (seriación de TnT de cuarta generación seguida de ergometría cuando fue negativa). Se indicó coronariografía invasiva si las troponinas, la ATCC o la ergometría fueron positivas. Se registró el resultado de la coronariografía invasiva, el tiempo diagnóstico y la aparición de un evento adverso (muerte por cualquier causa, nuevo infarto de miocardio, nueva angina inestable o necesidad de revascularización) durante los 3 meses de seguimiento. RESULTADOS: De los 102 pacientes aleatorizados se excluyeron 7. Se incluyeron 95 pacientes, 45 asignados a la EC y 50 a la EN. La coronariografía mostró lesiones significativas en un 92,9% de los casos de la EN y en un 66,7% de la EC. La proporción de pacientes diagnosticados en las primeras 6 horas fue mayor en la EN en comparación con la EC (20,0% vs 4,4%; p = 0,023). Durante el periodo de 3 meses de seguimiento, se registró una muerte en la EN y ningún evento en la EC. CONCLUSIONES: La EN podría aportar un diagnóstico más rápido, así como una mayor probabilidad de encontrar lesiones coronarias significativas, sin diferencias en la aparición de eventos adversos en los 3 primeros meses. Estos hallazgos necesitan ser confirmados en futuros estudios con mayor número de pacientes.

Alteração de biomarcadores de lesão miocárdica em atletas após a Maratona Internacional de São Paulo / Changes in biomarkers of myocardial lesion in runners after the São Paulo International Marathon / Alteración de biomarcadores de lesión miocárdica en atletas después de Maratón Internacional de San Pablo

INTRODUÇÃO: Apesar de a prática regular de exercício físico reduzir o risco de doença cardiovascular, estudos recentes têm documentado elevações em biomarcadores relacionados com danos cardíacos após exercícios prolongados em indivíduos aparentemente saudáveis. OBJETIVO: Investigar as alterações nos níveis de brain natriuretic peptide (BNP) e troponina T cardíaca (cTnT) em atletas amadores após uma maratona, assim como verificar as possíveis relações entre as alterações, antes e depois da prova, apresentada pelos dois biomarcadores e variáveis do teste cardiopulmonar. MÉTODOS: Estudamos 38 atletas do sexo masculino (40,9 ± 6,29 anos) antes e depois da Maratona Internacional de São Paulo, SP, Brasil. Foram realizadas coletas de sangue na veia antecubital para mensurar os biomarcadores cardíacos, cTnT e BNP 24h antes, imediatamente após e 24h após a maratona. Foi realizado teste cardiopulmonar máximo nas três semanas que antecederam a prova. RESULTADOS: Os valores de BNP e cTnT aumentaram imediatamente após a maratona (p<0,001) quando comparados com os valores basais. No terceiro momento (24h) os valores de troponina tiveram uma redução significativa caracterizando um retorno aos valores basais. Não encontramos correlação entre idade e variáveis referentes a intensidade da maratona, porém encontramos correlação dos biomarcadores com o tempo de conclusão da maratona. CONCLUSÃO: Diferentes causas de liberação podem ser assumidas para cTnT e BNP e, neste caso, parecem não refletir dano miocárdico devido ao comportamento da curva destes marcadores, além de não haver relação entre a liberação dos dois biomarcadores. .

INTRODUCTION: Although the practice of physical exercises reduces the cardiovascular risk, recent studies have documented elevations in cardiac injury biomarkers after prolonged exercises in apparently healthy individuals. OBJECTIVE: We aimed to investigate the changes in brain natriuretic peptide (BNP) and cardiac troponin T (cTnT) levels after a marathon, and the correlation of these biomarkers and the variables of cardiopulmonary test. METHODS: We studied 38 male athletes (40.9 ± 6.29 years old) participants at the São Paulo International Marathon, SP, Brasil. Blood collections were performed to measure cTnT and BNP 24h before, immediately after and 24h after the marathon. Cardiopulmonary test was performed in the three weeks preceding the marathon. RESULTS: BNP and cTnT values increased significantly after the marathon (p<0.001). In the third moment (24h) the troponin values returned to the baseline values. We found no correlation between age and variables of the marathon, however, we did find a correlation between the biomarkers and time to complete the marathon. CONCLUSION: Various causes of release may be presumed for cTnT and BNP, however, they do not seem to reflect into myocardial injury, and there is no relationship between the releases of the two biomarkers. .

INTRODUCCIÓN: A pesar de que la práctica regular de ejercicio reduce el riesgo de enfermedad cardiovascular, estudios recientes han documentado elevaciones en biomarcadores relacionados con daños cardiacos después de ejercicios prolongados en individuos aparentemente saludables. OBJETIVO: Investigar las alteraciones en los niveles de BNP y troponina T cardiaca (cTnT) en atletas amateur después de maratón, así como verificar las posibles relaciones entre las alteraciones, antes y después de la prueba, presentada por dos biomarcadores y variables del test cardiopulmonar. MÉTODOS: Estudiamos 38 atletas del sexo masculino (40,9±6,29 años) antes y después de la Maratón Internacional de São Paulo, SP, Brasil. Fueron realizadas colectas de sangre en la vena antecubital para medir los biomarcadores cardiacos, cTnT y BNP, 24 horas antes, inmediatamente y 24 horas después de la Maratón. Fue realizado test cardiopulmonar máximo en las tres semanas que antecedieron a la maratón. RESULTADOS: Los valores de BNP y cTnT aumentaron inmediatamente después de la maratón (p<0,001) cuando comparados con los valores basales. En el tercer momento (24h) los valores de troponina tuvieron una reducción significativa caracterizando un retorno a los valores basales. No encontramos correlación entre edad y variables referentes a intensidad de la maratón, sin embargo encontramos correlación de los biomarcadores con el tiempo de conclusión de la maratón. CONCLUSIÓN: Diferentes causas de liberación pueden ser asumidas para cTnT y BNP y, en este caso, parecen no reflejar daño miocárdico debido al comportamiento de la curva de estos marcadores, además de no haber relación entre la liberación de los dos biomarcadores. .

[Clinical interpretation of high sensitivity troponin T]. / Interpretación clínica de la determinación de troponina T de elevada sensibilidad.

Determination of cardiac troponin (cTn) is necessary for the diagnosis of acute myocardial infarction without ST segment elevation. However Tnc can be released in other clinical situations. The development of high-sensitive cTn T assays (hs-cTnT) improves the management of patients with suspected acute coronary syndrome. Here, we provide an overview of the diverse causes of hs-cTnT elevation and recommend strategies for the clinical interpretation of the test result.

Evaluación de un nuevo algoritmo diagnóstico para el síndrome coronario agudo con determinación de troponina T de alta sensibilidad / Evaluation of a New Diagnostic Algorithm for Acute Coronary Syndrome Using High-Sensitivity Troponin T Assay

Introducción El dolor precordial representa el 5% al 10% de las consultas anuales en los departamentos de emergencias; su diagnóstico suele ser dificultoso y a ello se le suma el problema que implican la externación de pacientes con patología coronaria aguda o las internaciones innecesarias. Esto ha llevado al desarrollo de diferentes sistemáticas para la evaluación de estos pacientes. Objetivo Validar en términos de seguridad y tiempos de estadía hospitalaria un nuevo algoritmo incorporado en nuestro centro que incluye la medición de troponina T de alta sensibilidad en pacientes con sospecha de síndrome coronario agudo. Material y métodos Se incluyeron 528 pacientes que consultaron en el servicio de emergencias con sospecha de síndrome coronario agudo y se les realizó el protocolo de unidad de dolor. Se analizaron variables clínicas, de laboratorio y el resultado de las pruebas funcionales efectuadas. En todos los pacientes se efectuó seguimiento a los 30 días. Resultados El 90,7% de los pacientes fueron externados luego de la observación y al seguimiento el 1,25% había presentado un evento cardíaco, representado por angioplastia coronaria e internación por síndrome coronario agudo; la especificidad del algoritmo global para el diagnóstico de síndrome coronario agudo fue del 97% y el valor predictivo negativo fue del 99%. El tiempo de estadía en el servicio de emergencias del total de los pacientes fue de 4,5 ± 2,5 horas. Conclusión El nuevo algoritmo incorporado en nuestro centro con determinación de troponina T de alta sensibilidad en pacientes con sospecha de síndrome coronario agudo demostró que es seguro al evitar la externación de pacientes que cursaban un síndrome coronario agudo y, a la vez, requiere una corta estadía hospitalaria en el servicio de emergencias.

Introduction Chest pain represents 5 to 10% of annual visits to emergency departments. Its diagnosis is sometimes difficult, with the added problem of inappropriate discharge of patients with acute coronary syndrome or unnecessary hospitalizations. This has led to the development of different algorithms for the evaluation of these patients. Objective The aim of this study was to validate, in terms of safety and length of hospital stay, a novel algorithm incorporated in our center, which includes measurement of high-sensitivity troponin T in patients with suspected acute coronary syndrome. Methods The study included 528 consecutive patients attending the emergency department with suspected acute coronary syndrome and evaluated according to the chest pain unit protocol. Clinical and laboratory variables and functional tests were analyzed. Follow-up at 30 days was performed in all the patients. Results After observation, 90.7% of the patients were discharged and 1.25% presented a cardiovascular event during follow-up, represented by percutaneous coronary intervention and hospitalization due to acute coronary syndrome. The specificity of the global algorithm for the diagnosis of acute coronary syndrome was 97% with a negative predictive value of 99%. Emergency department length of stay was 4.5 ± 2.5 hours for all the patients. Conclusion The novel algorithm incorporated in our center with measurement of high-sensitivity troponin T in patients with suspected acute coronary syndrome has proved to be safe, as it prevents the discharge of patients with acute coronary syndrome and at the same time reduces emergency department length of stay.