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.

Elevated High-Sensitivity Troponin I in the Stabilized Phase after an Acute Coronary Syndrome Predicts All-Cause and Cardiovascular Mortality in a Highly Admixed Population: A 7-Year Cohort / A Troponina I de Alta Sensibilidade Elevada na Fase Estabilizada após Síndrome Coronariana Aguda Prevê Mortalidade por Todas as Causas e Mortalidade Cardiovascular em uma População Altamente Miscigenada: Uma Coorte de 7 Anos

Abstract Background: High-sensitivity cardiac troponin I (hs-cTnI) has played an important role in the risk stratification of patients during the in-hospital phase of acute coronary syndrome (ACS), but few studies have determined its role as a long-term prognostic marker in the outpatient setting. Objective: To investigate the association between levels of hs-cTnI measured in the subacute phase after an ACS event and long-term prognosis in a highly admixed population. Methods: We measured levels of hs-cTnI in 525 patients 25 to 90 days after admission for an ACS event; these patients were then divided into tertiles according to hs-cTnI levels and followed for up to 7 years. We compared all-cause and cardiovascular mortality using Cox proportional hazards models and adopting a significance level of 5%. Results: After a median follow-up of 51 months, patients in the highest tertile had a greater hazard ratio (HR) for all-cause mortality after adjustment for age, sex, known cardiovascular risk factors, medication use, and demographic factors (HR: 3.84, 95% CI: 1.92-8.12). These findings persisted after further adjustment for estimated glomerular filtration rate < 60 ml/min/1.73 m2 and left ventricular ejection fraction < 0.40 (HR: 6.53, 95% CI: 2.12-20.14). Cardiovascular mortality was significantly higher in the highest tertile after adjustment for age and sex (HR: 5.65, 95% CI: 1.94-16.47) and both in the first (HR: 4.90, 95% CI: 1.35-17.82) and second models of multivariate adjustment (HR: 5.89, 95% CI: 1.08-32.27). Conclusions: Elevated hs-cTnI levels measured in the stabilized phase after an ACS event are independent predictors of all-cause and cardiovascular mortality in a highly admixed population.

Resumo Fundamento: A troponina cardíaca de alta sensibilidade I (TnI-as) tem desempenhado um papel importante na estratificação de risco dos pacientes durante a fase intra-hospitalar da síndrome coronariana aguda (SCA), mas poucos estudos determinaram seu papel como marcador prognóstico de longo prazo no ambiente ambulatorial. Objetivo: Investigar a associação entre os níveis de TnI-as medidos na fase subaguda após um evento de SCA e o prognóstico a longo prazo, em uma população altamente miscigenada. Métodos: Medimos os níveis de TnI-as em 525 pacientes em um período de 25 a 90 dias após a entrada em hospital por um evento de SCA; esses pacientes foram então divididos em tercis conforme os níveis de TnI-as, e acompanhados por até 7 anos. Comparamos as mortalidades por todas as causas e cardiovascular através de modelos de riscos proporcionais de Cox e adotando um nível de significância de 5%. Resultados: Após um acompanhamento médio de 51 meses, os pacientes no tercil mais alto apresentaram uma taxa de risco (HR) maior para mortalidade por todas as causas, após ajustes para idade, sexo, fatores de risco cardiovascular conhecidos, uso de medicação e fatores demográficos (HR: 3,84 IC 95%: 1,92-8,12). Esses achados persistiram após um ajuste adicional para uma taxa de filtração glomerular (TFG) estimada < 60 ml/min/1,73 m2 e uma fração de ejeção do ventrículo esquerdo < 0,40 (HR: 6,53; IC95%: 2,12-20,14). A mortalidade cardiovascular foi significativamente maior no tercil mais alto, após ajustes para idade e sexo (RR: 5,65; IC95%: 1,94-16,47) e tanto no primeiro modelo de ajuste multivariado (HR: 4,90; IC 95%: 1,35-17,82) quanto no segundo (HR: 5,89; IC95%: 1,08-32,27). Conclusões: Níveis elevados de TnI-as, medidos na fase estabilizada após um evento de SCA, são preditores independentes de mortalidade por todas as causas e de mortalidade cardiovascular em uma população altamente miscigenada.

Injuria miocárdica postcirugía no cardiaca (MINS) en pacientes sometidos a cirugía vascular: artículo de revisión / Myocardial injury after noncardiac surgery (MINS) in major vascular surgery, a review

Vascular surgery is considered high risk, due to the characteristics of patients and surgical procedures. Recently, the diagnosis of myocardial injury after non-cardiac surgery (MINS) was introduced to focus attention on the prognostic relevance of elevated ischemic troponin after non-cardiac surgery. In the study Vascular Events In Noncardiac Surgery Patients Cohort Evaluation (VISION), that included more than 15,000 patients who underwent non-cardiac surgery, MINS was independently associated with mortality 3 to 4 times greater than 30 days after surgery. Biccard et al published a study derived from the study VISION in which 502 patients underwent vascular surgery, resulting in significantly higher mortality (12.5% vs 1.5%, p < 0.001) in patients who developed MINS compared to those who did not develop MINS (OR 9.48, 95% CI, 3.46-25.96). The 2014 guidelines for preoperative cardiovascular evaluation of the American College of Cardiology/American Heart Association (ACC/AHA) do not recommend the postoperative surveillance of troponin in patients without symptoms or signs of myocardial ischemia, nor in patients at high risk of coronary disease (as patients undergoing vascular surgery). On the other hand, the 2017 guidelines of the Canadian Cardiovascular Society on Perioperative Cardiac Risk, evaluation and treatment for non-cardiac surgery patients, recommend obtaining daily measurements of troponin for 48 to 72 hours after of non-cardiac surgery, in patients with a baseline risk of more than 5% of cardiovascular death or acute non-fatal myocardial infarction at 30 days after surgery. MINS is a potentially useful marker of adverse postoperative outcomes and its detection could provide opportunities to improve clinical outcomes in affected patients.

La cirugía vascular es considerada de alto riesgo, debido a características propias de los pacientes y de los procedimientos quirúrgicos. Recientemente, se introdujo el diagnóstico de injuria miocárdica postcirugía no cardiaca (MINS) para centrar la atención en la relevancia pronóstica de la elevación de la troponina isquémica después de una cirugía no cardíaca. Dos grandes estudios han demostrado que la mortalidad es significativamente mayor en pacientes que desarrollaron MINS. Las guías 2014 de evaluación cardiovascular preoperatoria de American College of Cardiology/American Heart Association (ACC/AHA), no recomiendan la vigilancia postoperatoria de troponina en pacientes sin síntomas ni signos de isquemia miocárdica ni tampoco en pacientes con alto riesgo de infarto al miocardio (como pacientes sometidos a cirugía vascular). Sin embargo, las guías de sociedad cardiovascular canadiense (publicadas en 2017) sobre riesgo cardíaco perioperatorio, evaluación y tratamiento para pacientes de cirugía no cardíaca] recomiendan obtener mediciones diarias de troponina durante 48 a 72 horas después de cirugía no cardíaca, en pacientes con un riesgo basal superior al 5% de muerte cardiovascular o infarto agudo al miocardio no fatal a 30 días después de una cirugía. MINS se debe considerar como un marcador potencialmente útil de resultados postoperatorios adversos y su detección podría brindar oportunidades para mejorar los resultados clínicos en los pacientes afectados.

Alprostadil attenuates myocardial ischemia/reperfusion injury by promoting antioxidant activity and eNOS activation in rats

Abstract Purpose: To investigate the effect of alprostadil on myocardial ischemia/reperfusion (I/R) in rats. Methods: Rats were subjected to myocardial ischemia for 30 min followed by 24h reperfusion. Alprostadil (4 or 8 μg/kg) was intravenously administered at the time of reperfusion and myocardial infarct size, levels of troponin T, and the activity of creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) in the serum were measured. Antioxidative parameters, nitric oxide (NO) content and phosphorylated endothelial nitric oxide synthase 3 (p-eNOS) expression in the left ventricles were also measured. Histopathological examinations of the left ventricles were also performed. Results: Alprostadil treatment significantly reduced myocardial infarct size, serum troponin T levels, and CK-MB and LDH activity (P<0.05). Furthermore, treatment with alprostadil significantly decreased malondialdehyde (MDA) content (P<0.05) and markedly reduced myonecrosis, edema and infiltration of inflammatory cells. Superoxide dismutase and catalase activities (P<0.05), NO level (P<0.01) and p-eNOS (P<0.05) were significantly increased in rats treated with alprostadil compared with control rats. Conclusion: These results indicate that alprostadil protects against myocardial I/R injury and that these protective effects are achieved, at least in part, via the promotion of antioxidant activity and activation of eNOS.

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.

Plasma Levels of Soluble CD146 Reflect the Severity of Pulmonary Congestion Better Than Brain Natriuretic Peptide in Acute Coronary Syndrome

BACKGROUND: Acute heart failure negatively affects short-term outcomes of patients with acute coronary syndrome (ACS). Therefore, reliable and non-invasive assessment of pulmonary congestion is needed to select patients requiring more intensive monitoring and therapy. Since plasma levels of natriuretic peptides are influenced by myocardial ischemia, they might not reliably reflect congestion in the context of ACS. The novel endothelial biomarker, soluble CD146 (sCD146), presents discriminative power for detecting the cardiac origin of acute dyspnea similar to that of natriuretic peptides and is associated with systemic congestion. We evaluated the performance of sCD146 for the assessment of pulmonary congestion in the early phase of ACS. METHODS: One thousand twenty-one consecutive patients with ACS were prospectively enrolled. Plasma levels of sCD146, brain natriuretic peptide (BNP), and high-sensitive troponin T were measured within 24 hr after the onset of chest pain. Pulmonary congestion on chest radiography was determined and classified in three groups according to the degree of congestion. RESULTS: Nine hundred twenty-seven patients with ACS were analyzed. Ninety-two (10%) patients showed signs of pulmonary edema on chest radiography. Plasma levels of sCD146 reflected the radiological severity of pulmonary congestion. Higher plasma levels of sCD146 were associated with the worse degree of pulmonary congestion. In contrast to BNP, sCD146 levels were not affected by the level of troponin T. CONCLUSIONS: The novel endothelial biomarker, sCD146, correlates with radiological severity of pulmonary congestion in the early phase of ACS and, in contrast to BNP, is not affected by the amount of myocardial cell necrosis.

Coronary Microembolization with Normal Epicardial Coronary Arteries and No Visible Infarcts on Nitrobluetetrazolium Chloride-Stained Specimens: Evaluation with Cardiac Magnetic Resonance Imaging in a Swine Model

OBJECTIVE: To assess magnetic resonance imaging (MRI) features of coronary microembolization in a swine model induced by small-sized microemboli, which may cause microinfarcts invisible to the naked eye. MATERIALS AND METHODS: Eleven pigs underwent intracoronary injection of small-sized microspheres (42 microm) and catheter coronary angiography was obtained before and after microembolization. Cardiac MRI and measurement of cardiac troponin T (cTnT) were performed at baseline, 6 hours, and 1 week after microembolization. Postmortem evaluation was performed after completion of the imaging studies. RESULTS: Coronary angiography pre- and post-microembolization revealed normal epicardial coronary arteries. Systolic wall thickening of the microembolized regions decreased significantly from 42.6 +/- 2.0% at baseline to 20.3 +/- 2.3% at 6 hours and 31.5 +/- 2.1% at 1 week after coronary microembolization (p < 0.001 for both). First-pass perfusion defect was visualized at 6 hours but the extent was largely decreased at 1 week. Delayed contrast enhancement MRI (DE-MRI) demonstrated hyperenhancement within the target area at 6 hours but not at 1 week. The microinfarcts on gross specimen stained with nitrobluetetrazolium chloride were invisible to the naked eye and only detectable microscopically. Increased cTnT was observed at 6 hours and 1 week after microembolization. CONCLUSION: Coronary microembolization induced by a certain load of small-sized microemboli may result in microinfarcts invisible to the naked eye with normal epicardial coronary arteries. MRI features of myocardial impairment secondary to such microembolization include the decline in left ventricular function and myocardial perfusion at cine and first-pass perfusion imaging, and transient hyperenhancement at DE-MRI.

Colesterol HDL y troponina T ultrasensible como biomarcadores predictivos de fibrilación auricular postoperatoria / HDL cholesterol and high-sensitive troponin T as predictives biomarkers of atrial fibrillation after heart surgery

Introducción: La fibrilación auricular (FA), con una incidencia aproximada del 30%, es la arritmia más frecuente tras cirugía cardiaca. Se han asociado a la FA factores como la inflamación, la presencia de fibrosis cardiaca, el estrés y la apoptosis de cardiomiocitos. Objetivos: Consideramos que el remodelado auricular es un proceso preexistente en los pacientes con FA posquirúrgica. Analizamos los factores relacionados con la incidencia de FA en el postoperatorio de cirugía cardiaca. Métodos: Incluimos a pacientes consecutivos, estables hemodinámicamente y en ritmo sinusal, sometidos a cirugía cardiaca programada con circulación extracorpórea. Se valora la caída en FA posquirúrgica. Resultados: Se incluyeron un total de 100 pacientes sometidos a cirugía de revascularización coronaria (59) o sustitución valvular aórtica (41) por estenosis aórtica grave. La FA postoperatoria se produjo en 29 pacientes con predominio de la cirugía valvular respecto a la cirugía coronaria. Los factores predictivos de la aparición de FA postoperatoria en el análisis multivariable fueron el sexo masculino, la ausencia de terapia crónica con betabloqueadores, la perfusión de fibrinógeno intraoperatorio, valores bajos de colesterol HDL y valores elevados de troponina T ultrasensible en el preoperatorio. Conclusiones: El colesterol HDL y la troponina T ultrasensible pueden ser biomarcadores útiles para predecir la aparición de FA postoperatoria. La identificación precoz de estos pacientes nos permite adoptar medidas preventivas para minimizar sus efectos negativos.

Introduction: Atrial fibrillation (AF) has an incidence rate of approximately 30% and is the most frequent arrhythmia following heart surgery. Factors such as inflammation, the presence of heart fibrosis, stress and cardiomyocyte apoptosis, have all been associated with AF. Objectives: We believe that atrial remodelling is a pre-existent process in patients with post-surgical AF. We have analyzed the factors related to the incidence of atrial fibrillation in the period after heart surgery. Methods: We included consecutive, hemodynamically stable patients with a sinusal rhythm who were subjected to programmed heart surgery with extracorporeal circulation. An assessment was made of the fall in atrial fibrillation after surgery using prolonged electrocardiographic monitoring. Results: A total of 100 patients were included in the study and were subjected to either coronary revascularisation surgery (59) or aortic valve substitution due to severe aortic stenosis (41). Postoperative AF occurred in 29 patients who received predominantly more valve surgery than coronary surgery. The following factors were predictive of postoperative AF in the multivariate analysis: Male sex; beta-blocker therapy for chronic disease; the use of intraoperative; fibrinogen perfusion; low HDL cholesterol values; and high sensitive troponin T values, in the preoperative period. Conclusions: HDL cholesterol and high sensitive troponin T can be useful biomarkers to predict the occurrence of AF after surgery. The early identification of these patients who develop of FA allows us to take preventive measures to minimize the negative effects.

Prevalence of myocarditis in pediatric intensive care unit cases presenting with other system involvement / Prevalência de miocardite em casos pediátricos na unidade de terapia intensiva, com envolvimento de outros sistemas

OBJECTIVE: To assess children with myocarditis, the frequency of various presenting symptoms, and the accuracy of different investigations in the diagnosis. METHODS: This was an observational study of 63 patients admitted to PICU with non-cardiac diagnosis. Cardiac enzymes, chest-X ray, echocardiography, and electrocardiogram were performed to diagnose myocarditis among those patients. RESULTS: There were 16 cases of definite myocarditis. The age distribution was non-normal, with median of 5.5 months (3.25-21). Of the 16 patients who were diagnosed with myocarditis, 62.5% were originally diagnosed as having respiratory problems, and there were more females than males. Among the present cases, the accuracy of cardiac enzymes (cardiac troponin T [cTn] and creatine phosphokinase MB [CKMB]) in the diagnosis of myocarditis was only 63.5%, while the accuracy of low fractional shortening and of chest-X ray cardiomegaly was 85.7 and 80.9%; respectively. Cardiac troponin folds 2.02 had positive predictive value of 100%, negative predictive value of 88.7%, specificity of 100%, sensitivity of 62.5%, and accuracy of 90.5%. CONCLUSIONS: Children with myocarditis present with symptoms that can be mistaken for other types of illnesses. When clinical suspicion of myocarditis exists, chest-X ray and echocardiography are sufficient as screening tests. Cardiac troponins confirm the diagnosis in screened cases, with specificity of 100%. .

OBJETIVO: Determinar as crianças com miocardite, a frequência de sintomas apresentados e a precisão de investigações no diagnóstico. MÉTODOS: Estudo observacional de 63 pacientes internados na UTIP com diagnóstico de problemas não cardíacos. Os exames de enzimas cardíacas, raios-X do tórax, ecocardiograma e eletrocardiograma (ECG) foram feitos para diagnosticar miocardite entre os pacientes. RESULTADOS: Houve 16 casos de miocardite definida. A distribuição etária não foi normal, com média de 5,5 meses (3,25-21). Dos 16 pacientes, 62,5% foram originalmente diagnosticados com problemas respiratórios e a mulheres estavam em maior número do que os homens. Dentre nossos casos, a precisão das enzimas cardíacas (cTn e CKMB) no diagnóstico da miocardite foi de apenas 63,5%, apesar de a precisão da baixa fração de encurtamento (FS) e dos raios-X de tórax que revelaram cardiomegalia ter sido 85,7% e 80,9%; respectivamente. A troponina cardíaca em 2,02 vezes apresentou valor preditivo positivo = 100%, valor preditivo negativo = 88,7%, especificidade = 100%, sensibilidade = 62,5% e precisão = 90,5%. CONCLUSÕES: As crianças com miocardite apresentam sintomas que podem ser confundidos com outros tipos de doenças. Quando há suspeita clínica de miocardite, raios-X de tórax e ecocardiografia são testes de rastreamento suficientes. As troponinas cardíacas confirmam o diagnóstico em casos examinados, com especificidade de 100%. .

Comparing the diagnostic values of circulating microRNAs and cardiac troponin T in patients with acute myocardial infarction

OBJECTIVE: Recent studies have shown that circulating microRNAs might be useful, novel biomarkers for the diagnosis of acute myocardial infarction. The aims of this study were to evaluate the expression of cardiac-specific miRNAs (miR-1, -133a, -208b, and -499) in patients with acute myocardial infarction and to compare the diagnostic values of these miRNAs with that of cardiac troponin T. METHODS: Sixty-seven plasma samples obtained from patients with acute myocardial infarction and 32 plasma specimens collected from healthy volunteers were analyzed in this study. The levels of cardiac-specific miRNAs (miR-1, -133a, -208b, and -499) were measured by quantitative reverse transcription-polymerase chain reaction, and the concentrations of plasma cardiac troponin T were measured using electrochemiluminescence-based methods and an Elecsys 2010 Immunoassay Analyzer. RESULTS: The levels of plasma miR-1, -133a, -208b, and -499 were significantly higher in acute myocardial infarction patients (all p<0.001) than in healthy volunteers. The expression of the cardiac-specific miRNAs in acute myocardial infarction patients decreased to close to the baseline levels at the time of hospital discharge (all p>0.05). There were no correlations between the levels of the four circulating miRNAs and the clinical characteristics of the study population (all p>0.05). Furthermore, receiver operating characteristic curve analyses showed that the four plasma miRNAs were not superior to cardiac troponin T for the diagnosis of acute myocardial infarction (all p>0.05). CONCLUSION: Our results demonstrate that circulating miR-1, -133a, -208b, and -499 may be useful biomarkers in acute myocardial infarction patients but that these miRNAs are not superior to cardiac troponin T for the diagnosis of acute myocardial infarction.

Association of BMI with elevated values of CK-MB and cTnT in acute myocardial infarction

To determine the association of BMI with serum levels of cTnT and CK-MB isoenzyme in patients presented to hospital emergency with suspected myocardial infarction and in healthy individuals. Comparative cross sectional study. This study was conducted at Post graduate medical institute, Lahore in collaboration with Punjab Institute of Cardiology Lahore from July 2010 to Dec 2010. Serum concentration of CK-MB and Cardiac Troponin T were estimated in 80 patients of AMI [40-60 years of age both sexes] by Immunological UV assay and electrochemiluminescence immunoassay [ECLIA] respectively. 40 healthy controls were matched for age and sex. Low BMI was observed in patients with both sexes. The values of both CK-MB and cTnT were markedly raised in patients with acute myocardial infarction. In the present study higher prevalence of risk factors and MI were seen in patients even with BMI < 23 kg/m 2.Therefore recognition and adoption of BMI cutoffs represent a major step forward in redefining the risk stratification among Pakistanis

Serum Troponin-I as a prognostic marker in acute exacerbated chronic obstructive pulmonary disease patients

Background: Chronic Obstructive Pulmonary Disease [COPD] is a major cause of chronic morbidity and mortality worldwide. It is the fifth leading cause of death worldwide. The spectrum of cardiovascular complications associated with COPD is clearly broad, right ventricular [RV] dysfunction and pulmonary vascular disease are common in COPD and progress with time. In RV failure, cardiac Troponins [cTn] are suspected to be elevated secondary to RV ischemia or micro infarction

Objective: To evaluate the prognostic value of cardiac Troponin I level in acute exacerbated chronic obstructive pulmonary diseases [AECOPD] and its impact on the hospital outcome in those patients

Patients and methods: This study was performed on 60 patients with AECOPD, admitted at Chest Department and respiratory ICU; Zagazig University hospital. All patients were subjected to: thorough history taking, clinical examination, electrocardiography and echocardiography, arterial blood gas [ABG] analysis, measure forced vital capacity [FVC] and forced expiratory volume in first second [FEV1], serum assay of cTnI level which is considered -ve if <0.01 ng/ml and +ve if >/=0.01 ng/ml

Results: cTnI was positive in 42 AECOPD patients. cTnI positivity was more prominent among patients with very severe exacerbation of COPD and in those with past history of LTOT, MV, ICU admission. Also, cTnI positivity was more in patients admitted to ICU rather than those managed in the ward and among patients who needed MV rather than who did not need it and in patients who failed weaned rather that who succeeded weaned. P-pulmonate, Rt. ventricular strain, high pulmonary artery pressure, hypoxemia and hypercapnia showed a great effect upon cTnI positivity. The duration of hospitalization was longer among cTnI +ve patients than cTnI ?ve ones, Tropinin cutoff value for the prediction of death was >0.055 ng/ml with Sensitivity = 75%, Specificity = 68%

Conclusion: Positive cTnI in AECOPD patients may suggest exacerbation severity and the occurrence of pulmonary hypertension and right ventricular dysfunction. Positive cTnI is considered as good prognostic marker for the possibility of a need for MV and a longer duration of hospitalization. MV may further elevate cTnI in AECOPD patients and with possible weaning failure. Negative cTnI and cTnI

Valor prognóstico da troponina I de alta sensibilidade versus troponina T nas síndromes coronarianas agudas / Prognostic value of high-sensitivity troponin I versus troponin T in acute coronary syndromes

FUNDAMENTO: Apesar da superior precisão diagnóstica das troponinas cardíacas de alta sensibilidade, seu valor prognóstico ainda não foi validado contra troponinas cardíacas convencionais. OBJETIVO: Testar o valor prognóstico da troponina I de alta sensibilidade (TnI-as) em comparação com a troponina T convencional (TnT-c) no cenário de síndromes coronarianas agudas sem supradesnivelamento do segmento ST (SCA). MÉTODOS: No momento da admissão, uma amostra de plasma foi coletada de 103 pacientes consecutivos com angina instável ou infarto agudo do miocárdio sem supradesnivelamento do segmento ST. Nessa amostra, a troponina foi medida tanto pelo método TnI-as quanto pelo método TnT-c. O valor prognóstico das duas troponinas foi comparado em relação à ocorrência de evento cardiovascular maior, definido como o composto de morte, infarto agudo do miocárdio não fatal ou angina instável refratária durante a internação. RESULTADOS: Durante uma hospitalização mediana de 8 dias (intervalo interquartil = 5-11), a incidência de eventos cardiovasculares foi 10% (5 mortes, 3 infartos não fatais e 2 anginas refratárias não fatais). Troponina I de alta sensibilidade predisse significativamente eventos cardiovasculares, com C-estatísticas de 0,73 (95% CI = 0,59-0,87), à semelhança da TnT-c (0,70; 95% CI = 0,55-0,84) - P = 0,75. A definição de troponina positiva que proporcionou melhor acurácia prognóstica foi TnI-as > 0,055 mg / L e TnT-c > 0,010 mg / L, com sensibilidade de 90% e especificidade de 52% para ambos os ensaios. CONCLUSÃO: Troponina I de alta sensibilidade prediz eventos cardiovasculares de forma semelhante à troponina T convencional no cenário de SCA. (Arq Bras Cardiol. 2012; [online].ahead print, PP.0-0).

BACKGROUND: Despite superior diagnostic accuracy of high-sensitivity cardiac troponins, their prognostic value has not been validated against conventional cardiac troponins. OBJECTIVE: To test the prognostic value of high-sensitivity cardiac troponin I (hs-cTnI), compared with conventional cardiac troponin T (cTnT) in the setting of non-ST elevation acute coronary syndromes. METHODS: At hospital admission, a plasma sample was collected from 103 consecutive patients with unstable angina or non-ST elevation acute myocardial infarction. In this sample, troponin was measured both by hs-cTnI and cTnT methods. Their prognostic value was compared as to the occurrence of major cardiovascular events, defined as a combination of death, nonfatal acute myocardial infarction or refractory unstable angina during hospitalization. RESULTS: During median hospitalization of 8 days (interquartile range = 5 - 11), the incidence of cardiovascular events was 10% (5 deaths, 3 non-fatal myocardial infarctions and 2 non-fatal refractory anginas). High-sensitivity troponin I significantly predicted cardiovascular events, with a C-statistics of 0.73 (95% CI = 0.59 - 0.87), similarly to cTnT (0.70; 95% CI = 0.55 - 0.84) - P = 0.75. The definition of positive cardiac marker that provided the best prognostic accuracy was hs-cTnI > 0.055 µg/L and cTnT > 0.010 µg/L, with equal sensitivity of 90% and specificity of 52% for both assays. Positive hs-cTnI was associated with 17% incidence of events, compared with 2% in patients with negative hs-cTnI (P = 0.02). CONCLUSION: High-sensitivity troponin I predicts cardiovascular events similarly to conventional troponin T in the setting of non-ST-elevation ACS. (Arq Bras Cardiol. 2012; [online].ahead print, PP.0-0).

Predictive value of a 4-hour accelerated diagnostic protocol in patients with suspected ischemic chest pain presenting to an emergency department

Currently recommended risk stratification protocols for suspected ischemic chest pain in the emergency department [ED] includes point-of-care availability of exercise treadmill/nuclear tests or CT coronary angiograms. These tests are not widely available for most of the ED's. This study aims to prospectively validate the safety of a predefined 4-hour accelerated diagnostic protocol [ADP] using chest pain, ECG, and troponin T among suspected ischemic chest pain patients presenting to an ED of a tertiary care hospital in Oman. One hundred and thirty-two patients aged over 18 years with suspected ischemic chest pain presenting within 12 hours of onset along with normal or non-diagnostic first ECG and negative first troponin T [<0.010 microg/l] were recruited from September 2008 to February 2009. Low-probability acute coronary syndrome [ACS] patients at 4-hours defined as absent chest pain and negative ECG or troponin tests were discharged home and observed for 30-days for major adverse cardiac events [MACE] [Group I: negative ADP]. High-probability ACS patients at 4-hours were defined by recurrent or persistent chest pain, positive ECG or troponin tests and were admitted and observed for in-hospital MACE [Group II: positive ADP]. One hundred and thirty-two patients were recruited and 110 patients completed the study. The overall 30-day MACE in this cohort was 15% with a mortality of less than 1%. 30-days MACE occurred in 8/95 of group I patients [8.4%] and 9/15 of the in-hospital MACE patients in group II. The ADP had a sensitivity of 52% [95% CI: 0.28-0.76], specificity of 93% [0.85-0.97], a negative predictive value of 91% [0.83-0.96], a positive predictive value of 60% [0.32-0.82], negative likelihood ratio of 0.5 [0.30-0.83] and a positive likelihood ratio of 8.2 [3.3-20] in predicting MACE. A 4-hour ADP using chest pain, ECG, and troponin T had high specificity and negative predictive value in predicting 30-day MACE among low probability ACS patients discharged from ED. However, 30-day MACE in ADP negative patients was relatively high in contrast to guideline recommendations. Hence, there is a need to establish ED chest pain unit and adopt new protocols especially adding a point-of-care exercise treadmill test in the ED

comparative study of cardioprotective effect of three anesthetic agents by measuring serum level of troponin-T after coronary artery bypass grafting

Cardiac surgery is associated with some degree of myocardial injury. Preconditioning first described in 1986 was pharmacologic and non- pharmacologic. Among the long list of anesthetic drugs, isoflurane as an inhaling agent along with midazolam and propofol as injectable substances have been documented to confer some preconditioning effects on myocardium. In this study cardiac Troponin T [cTnT] ,as a reliable marker, was used for evaluating myocardial injury. This prospective double blind study was comprised of 60 patients scheduled for CABG and were randomly assigned into three groups who received infusion of propofol or midazolam or isoflorane. Surgical procedures and anesthetics were similar for 3 groups. cTnT measured preoperatively and at 12, 24 and 36hr after arrival in ICU. There were no statistically significant differences in mean cTnT levels between three groups in the preoperative period and 12-24 hours after arrival in ICU. However, mean cTnT in 3 groups at 36 hours after arrival in ICU were different [P< 0.013] and cTnT level was significantly higher in midazolam group [P<0.001] and lowest in isoflurane group [P=0.002]. There were significant differences on cTnT levels between anesthetic groups of isofluran, midazolam and propofol at 36 hr after surgery. Preconditioning effect of isoflurane was higher than the other two groups

Serum Thioredoxin 1 Level Has Close Relation with Myocardial Damage Amount in Acute Myocardial Infarction Patients

Thioredoxin-1 (Trx-1) is one of important anti-oxidative molecules to overcome the oxidative stress. The aim of the present study is to investigate the clinical relationship between serum concentration of Trx-1 on the pre-percutaneous coronary intervention (prePCI) and myocardial damage amount in the patients with acute myocardial infarction with the culprit lesion in only the left anterior descending artery on coronary angiography (n = 100). Initial value of creatine kinase (CK) was 368.3 +/- 531.4 U/L, and MB isoenzyme of CK (CK-MB) level was 22.92 +/- 33.8 ng/mL, and cardiac specific troponin T (cTnT) level was 0.61 +/- 1.6 ng/mL. Positive correlations were observed between prePCI Trx-1 level and initial CK (P = 0.005, r = 0.281), and cTnT (P < 0.001, r = 0.453), peak CK (P = 0.001, r = 0.316) in all patients, but the statistical relation was observed only in ST segment elevation myocardial infarction (STEMI) patients (P = 0.008, r = 0.329 for initial CK, P = 0.001, r = 0.498 for initial cTnT, P = 0.005, r = 0.349 for peak CK), not in Non-STEMI patients. Conclusively, we consider prePCI serum Trx-1 as a predictor for myocardial damage amount in patients with STEMI.

Trimetazidina na injúria de isquemia e reperfusão em cirurgia de revascularização do miocárdio / Trimetazidine on ischemic injury and reperfusion in coronary artery bypass grafting

FUNDAMENTO: A injúria de isquemia e reperfusão constitui um mecanismo fisiopatológico frequente e de difícil controle durante a Cirurgia de Revascularização do Miocárdio (CRVM) com circulação extracorpórea, sendo o momento crítico o término da cirurgia, quando ocorre o desclampeamento da aorta e a liberação dos radicais hiperóxidos causadores da injúria. OBJETIVO: Avaliar, em estudo prospectivo, duplo-cego randomizado, controlado com placebo, os efeitos da Trimetazidina (Tmz) sobre a injúria de isquemia e reperfusão miocárdica, identificando a variação dos marcadores plasmáticos de agressão miocárdica (troponina T e Cpk-Mb), e as alterações ecocardiográficas da função ventricular. MÉTODOS: Foram estudados 60 pacientes, divididos em dois grupos (Placebo e Tmz) com, no máximo, disfunção ventricular leve, estratificados por ecocardiografia e recebendo medicação/placebo na dose - no pré-operatório sem medicação, 12 a 15 dias de medicação/placebo colhida cinco minutos após o desclampeamento aórtico, e nas 12, 24 e 48 horas seguintes. RESULTADOS: Tanto a troponina T como a CpK-Mb atingiram valores altamente significativos (p = 0,0001) no grupo tratado em relação ao grupo controle nos quatro momentos analisados − 5 min, 12 h, 24 h e 48 h. As variáveis ecocardiográficas não evidenciaram mudanças evolutivas em cada grupo isoladamente e quando comparados em conjunto. CONCLUSÃO: A trimetazidina mostrou-se eficaz na redução da injúria de isquemia e reperfusão, não interferiu na função ventricular esquerda, e não foram observados efeitos colaterais.

BACKGROUND: The ischemia and reperfusion ischemia is a common physiopathological mechanisms, which has difficult control during Coronary Artery Bypass Grafting (CABG) with cardiopulmonary bypass, the critical moment of which happening by the end of surgery, when there is declamping of aorta and release of hyperoxic radicals causing the injury. OBJECTIVE: Evaluate, in a randomized double-blind prospective study, controlled with placebo, the effects of Trimetazidine (Tmz) on ischemic injury and myocardial reperfusion, identifying the change in plasma markers of a myocardial aggression (troponin T and CPK-MB), and echocardiographic changes of ventricular function. METHODS: We studied 60 patients divided in two groups (placebo and Tmz) with mild ventricular dysfunction at the most, stratified by echocardiography and receiving medication/placebo at a dose of 20 mg/3x/day, starting from 12 to 15 days after pre-operative period up to 5 to 8 days after post-operative period. Troponin T and Cpk-Mb were measured preoperatively without medication, 12 to 15 days of medication/placebo taken five minutes after aortic declamping, and at subsequent 12, 24 and 48 hours. RESULTS: Both Troponin T and Cpk-Mb reached highly significant values (p = 0.0001) in the treated group compared to the control group at the four moments analyzed - 5 min, 12h, 24h and 48h. The echocardiographic variables did not show evolutive changes in each group severally considered and when compared among themselves. CONCLUSION: Trimetazidine was effective in reducing ischemic injury and reperfusion, had no effect on left ventricular function, and no side effects were observed.

C-Reactive protein predicts acute myocardial infarction during high-risk noncardiac and vascular surgery

BACKGROUND: High-sensitivity C-reactive protein predicts cardiovascular events in a wide range of clinical contexts. However, the role of high-sensitivity C-reactive protein as a predictive marker for perioperative acute myocardial infarction during noncardiac surgery is not yet clear. The present study investigated high-sensitivity C-reactive protein levels as predictors of acute myocardial infarction risk in patients undergoing high-risk noncardiac surgery. METHODS: This concurrent cohort study included patients aged >50 years referred for high-risk noncardiac surgery according to American Heart Association/ACC 2002 criteria. Patients with infections were excluded. Electrocardiograms were performed, and biomarkers (Troponin I or T) and/or total creatine phosphokinase and the MB fraction (CPK-T/MB) were evaluated on the first and fourth days after surgery. Patients were followed until discharge. Baseline high-sensitivity C-reactive protein levels were compared between patients with and without acute myocardial infarction. RESULTS: A total of 101 patients undergoing noncardiac surgery, including 33 vascular procedures (17 aortic and 16 peripheral artery revascularizations), were studied. Sixty of the patients were men, and their mean age was 66 years. Baseline levels of high-sensitivity C-reactive protein were higher in the group with perioperative acute myocardial infarction than in the group with non-acute myocardial infarction patients (mean 48.02 vs. 4.50, p = 0.005). All five acute myocardial infarction cases occurred in vascular surgery patients with high CRP levels. CONCLUSIONS: Patients undergoing high-risk noncardiac surgery, especially vascular surgery, and presenting elevated baseline high-sensitivity C-reactive protein levels are at increased risk for perioperative acute myocardial infarction.

Cardiac enzymes activities and troponin-1 level in rabbit invested with intestinal and hepatic coccidiosis

This study was performed to elucidate the effect of both intestinal and hepatic coccidiosis on cardiac enzymes, GST, Catalase activities as well as troponine 1 level in rabbits. Furthermore, the study was extended to investigate the activities of the previous parameters after treatment of invested rabbits with coccidiosis. In this study, thirty six male rabbits were divided into 6 groups. Group 1 is a healthy control group. Groups 2, 3, 4, 5 and 6 were design as invested with intestinal type of coccidiosis, infected with hepatic type of coccidiosis, control treated with sulpha drug, infected with intestinal coccidiosis and treated with sulpha drug, infected with hepatic coccidiosis and treated with sulpha drug group, respectively. cardiac enzymes as AST, CPK, CPK-MB and LDH increased than the normal level during coccidial infection, either hepatic or intestinal type but it more pronounced in hepatic one after 7 and 14 days of infection. Also, troponine 1 level was increased significantly in the groups infected with intestinal and hepatic coccidiosis than the control group at 7 and 14 days from infection, whereas GST, Catalase activities decreased significantly in groups infected with either intestinal and hepatic coccidiosis than control one. Pretreatment with sulpha drugs improve the biochemical parameters changed by coccidial infections

A More Appropriate Cardiac Troponin T Level That Can Predict Outcomes in End-Stage Renal Disease Patients with Acute Coronary Syndrome

PURPOSE: Cardiac troponin T (cTnT), a useful marker for diagnosing acute myocardial infarction (AMI) in the general population, is significantly higher than the usual cut-off value in many end-stage renal disease (ESRD) patients without clinically apparent evidence of AMI. The aim of this study was to evaluate the clinical usefulness of cTnT in ESRD patients with acute coronary syndrome (ACS). MATERIALS AND METHODS: Two hundred eighty-four ESRD patients with ACS were enrolled between March 2002 and February 2008. These patients were followed until death or June 2009. Medical records were reviewed retrospectively. The cut-off value of cTnT for AMI was evaluated using a receiver operating characteristic (ROC) curve. We calculated Kaplan-Meier survival curves, and potential outcome predictors were determined by Cox proportional hazard analysis. RESULTS: AMIs were diagnosed in 40 patients (14.1%). The area under the curve was 0.98 in the ROC curve (p or =0.35 ng/mL compared to the other groups. Initial serum cTnT concentration was an independent predictor for mortality. CONCLUSION: Because ESRD patients with an initial cTnT concentration > or =0.35 ng/mL have a poor prognosis, it is suggested that urgent diagnosis and treatment be indicated in dialysis patients with ACS when the initial cTnT levels are > or =0.35 ng/mL.