En el Infarto agudo al miocardio los niveles plasmáticos de microvesículas extracelulares se elevan más precozmente que el aumento de la Troponina-I / Plasma levels of extracellular macrovesicles are elevated earlier than troponin-I in patients with myocardial infarction

Introducción: La Troponina I (TnI) plasmática es el biomarcador "Gold" estándar utilizado en diagnóstico de Infarto Agudo al Miocardio (IAM), indicando necrosis cardíaca. Las microvesículas extracelulares (MVEC), participan en comunicación celular, por lo que estudiar su distribución entregaría información respecto del evento isquémico, antesala del infarto. Objetivo: Estudiar las MVECs plasmáticas en pacientes con Síndrome Coronario Agudo (SCA) y compararlas con los niveles de TnI. Métodos: Plasma de 22 pacientes controles se recolectó 0-2hrs post-ingreso a urgencia. Plasma de 45 pacientes SCA se recolectó 0-2, 6-8 y 10-14hrs post ingreso, junto con la toma de muestra para estudio de TnI. Las MVECs plasmáticas fueron enriquecidas mediante kit comercial. La determinación de la concentración y tamaño MVECs se realizó por NTA (Nanoparticles Tracking Assay) usando el equipo Nanosight. Resultados: La concentración promedio de MVECs 0-2 hrs post ingreso fue 7,2 veces superior en plasma de pacientes con SCA vs controles y la moda del tamaño disminuyó en pacientes con SCA. La TnI no mostró diferencias significativas en 0-2 hrs post ingreso en el grupo estudiado. La concentración de las MVEC disminuyó significativamente después de 10-14 hrs post ingreso, mientras que la concentración promedio TnI se mantuvo invariable demostrando el aumento de MVECs previo al incremento de TnI. Conclusión. El aumento de MVECs previo al incremento de la TnI en pacientes infartados, sugiere que las MVECs aumentan en la fase previa del IAM, como respuesta al daño tisular. Actualmente, estudiamos el contenido molecular de las MVECs, para establecer un método diagnóstico del Síndrome Coronario Agudo basado en MVECs.

Background: Troponin I (TnI) is the gold standard used to establish the diagnosis of myocardial infarction (AMI), indicating the presence of myocardial necrosis. Extracellular micro vesicles are involved in cellular communication. Their distribution may provide information relating to the development of AMI in patients with acute coronary syndromes (ACS) Aim: to study plasma levels of ECMV compared to those of TnI in patients with ACS. Methods: The plasma levels of TnI and ECMV from 22 control patients coming to the emergency units was compared to plasma from 45 patients with ACS. Levels of both parameters were determined 0-2, 6-8 and 10-14 hours post admission. ECMVs were enriched by means of a commercial kit. Concentration and size of ECMV was determined by NTA (Nanoparticles tracking assay) using the Nanosight equipment. Results: Plasma concentration of ECMV was 7.2 times higher than that of TnI 0-2 hrs post admission. The mode of ECMV size was lower in patients with ACS. Concentration of ECMV had decreased significantly 10-14 hrs post admission, whereas the TnI levees remained stable. Conclusion: The increase in ECMV earlier than TnI in AMI suggests that ECMV are elevated in the pre-AMI phase, as a response to early tissue damage. A study of cellular content of ECMV, being carried out, may lead to develop a method for the early diagnosis of AMI in patients with ACS.

Metabolic interactions between hyperhomocysteinemia and endothelin-1 among Tunisian patients with acute coronary diseases

BACKGROUND: Acute coronary syndromes (ACS) are complex and polygenic diseases which are a real problem of public health. These syndromes require multidisciplinary studies to understand the pathogenesis mechanisms and metabolic interactions between different risk factors.This study aimed to explore the variation of two coronary risk parameters not mentioned by Framingham cohorts, hyperhomocysteinemia and endothelin-1 (ET-1) in Tunisian coronary and the study of the variation of these parameters based on various cardiac risk factors and metabolic relationship between them.To 157 coronary and 142 healthy subjects, the concentration of homocysteine was quantified by fluorescence polarization immunoassay; the concentration of ET-1 was measured by an analytical technique, the High Performance Liquid Chromatography (HPLC) coupled with mass spectrometry. RESULTS: Our study showed that homocysteine and ET-1 were significantly higher in patients compared to healthy subjects (24.40 ± 12.5 µmol/L vs 7.44 ± 2.5 µmol/L p <0.00001) for homocysteine and (15.2 ± 5.3 nmol/L vs 7.1 ± 2.7 nmol/L, p <0.00001) for ET-1. On the other hand, homocysteine varies according to tobacco and diabetes while ET-1 depends on the sex, hypertension, smoking, obesity and dyslipidemia and a statistically negative correlation was shown between homocysteine and ET-1 in coronary patients (r = -0.66 p <0.00001. CONCLUSION: The study of the variation of these two parameters in coronary patients and metabolic exploration of the relationship between homocysteine and ET-1 according to various risk factors and the interactions between themselves facilitates the decision of therapeutic treatment.

Association between Angiotensin-Converting Enzyme Inhibitors and Troponin in Acute Coronary Syndrome / Relação entre Inibidores da Enzima de Conversão da Angiotensina e Troponina na Síndrome Coronariana Aguda

Background: Cardiovascular disease is the leading cause of mortality in the western world and its treatment should be optimized to decrease severe adverse events. Objective: To determine the effect of previous use of angiotensin-converting enzyme inhibitors on cardiac troponin I measurement in patients with acute coronary syndrome without ST-segment elevation and evaluate clinical outcomes at 180 days. Methods: Prospective, observational study, carried out in a tertiary center, in patients with acute coronary syndrome without ST-segment elevation. Clinical, electrocardiographic and laboratory variables were analyzed, with emphasis on previous use of angiotensin-converting enzyme inhibitors and cardiac troponin I. The Pearson chi-square tests (Pereira) or Fisher's exact test (Armitage) were used, as well as the non-parametric Mann-Whitney's test. Variables with significance levels of <10% were submitted to multiple logistic regression model. Results: A total of 457 patients with a mean age of 62.1 years, of whom 63.7% were males, were included. Risk factors such as hypertension (85.3%) and dyslipidemia (75.9%) were the most prevalent, with 35% of diabetics. In the evaluation of events at 180 days, there were 28 deaths (6.2%). The statistical analysis showed that the variables that interfered with troponin elevation (> 0.5 ng / mL) were high blood glucose at admission (p = 0.0034) and ST-segment depression ≥ 0.5 mm in one or more leads (p = 0.0016). The use of angiotensin-converting inhibitors prior to hospitalization was associated with troponin ≤ 0.5 ng / mL (p = 0.0482). The C-statistics for this model was 0.77. Conclusion: This study showed a correlation between prior use of angiotensin-converting enzyme inhibitors and reduction in the myocardial necrosis marker troponin I in patients admitted for acute coronary syndrome without ST-segment elevation. However, there are no data available yet to state that this ...

Fundamento: A doença cardiovascular é a maior causa de mortalidade no mundo ocidental, devendo seu tratamento ser otimizado, para a redução de eventos adversos graves. Objetivo: Determinar o efeito do uso prévio de inibidores da enzima de conversão da angiotensina na mensuração da troponina I cardíaca em pacientes com síndrome coronariana aguda sem supradesnivelamento do segmento ST (SCASST), e avaliar os desfechos clínicos em até 180 dias. Métodos: Estudo prospectivo, observacional, em um centro terciário, em pacientes com síndrome coronariana aguda sem supradesnivelamento do segmento ST (SCASST). Foram analisadas variáveis clínicas, eletrocardiográficas e laboratoriais, com ênfase no uso prévio de inibidores da enzima de conversão da angiotensina e dosagem de troponina I cardíaca. Foram usados os testes qui quadrado de Pearson ou exato de Fischer , além do teste não paramétrico de Mann-Whitney. Variáveis com níveis de significância < 10% foram submetidas a modelo de regressão logística múltipla. Resultados: Incluídos 457 pacientes, com idade média de 62,1 anos, dos quais 63,7% eram do sexo masculino. Fatores de risco como hipertensão arterial sistêmica (85,3%) e dislipidemia (75,9%) foram os mais prevalentes, com 35% de diabéticos. Na avaliação de eventos em 180 dias, observaram-se 28 óbitos (6,2%). Na análise estatística, as variáveis que interferiram no aumento de troponina (> 0,5 ng/mL) foram a glicemia de admissão elevada (p = 0,0034) e o infradesnivelamento do segmento ST ≥ 0,5 mm, em uma ou mais derivações (p = 0,0016). Relacionada com troponina ≤ 0,5 ng/mL, esteve o uso de inibidores da enzima de conversão da angiotensina prévio à internação (p = 0,0482). ...

Interpretation and Use of Natriuretic Peptides in Non-Congestive Heart Failure Settings

Natriuretic peptides (NPs) have been found to be useful markers in differentiating acute dyspneic patients presenting to the emergency department (ED) and emerged as potent prognostic markers for patients with congestive heart failure (CHF). The best-established and widely used clinical application of BNP and NT-proBNP testing is for the emergent diagnosis of CHF in patients presenting with acute dyspnea. Nevertheless, elevated NPs levels can be found in many circumstances involving left ventricular (LV) dysfunction or hypertrophy; right ventricular (RV) dysfunction secondary to pulmonary diseases; cardiac inflammatory or infectious diseases; endocrinology diseases and high output status without decreased LV ejection fraction. Even in the absence of significant clinical evidence of volume overload or LV dysfunction, markedly elevated NP levels can be found in patients with multiple comorbidities with a certain degree of prognostic value. Potential clinical applications of NPs are expanded accompanied by emerging reports regarding screening the presence of secondary cardiac dysfunction; monitoring the therapeutic responses, risk stratifications and providing prognostic values in many settings. Clinicians need to have expanded knowledge regarding the interpretation of elevated NPs levels and potential clinical applications of NPs. Clinicians should recognize that currently the only reasonable application for routine practice is limited to differentiation of acute dyspnea, rule-out-diagnostic-tests, monitoring of therapeutic responses and prognosis of acute or decompensated CHF. The rationales as well the potential applications of NPs in these settings are discussed in this review article.

Perfil do atendimento ao paciente internado com síndrome isquêmica aguda sem supradesnível do segmento ST no Hospital Geral Nossa Senhora da Conceição, Tubarão – SC, 2006-2007 / Clinical Profile of Patients Interned with Acute Coronary syndrome Without ST Segment Elevation in a Hospital in South Brazil – 2006-2007

Objetivo: Descrever as características pessoais, clínicas, de tratamento, evolução para óbito e correlacionar escore TIMI ao número de internaçõesem UTI e transferência para cineangicoronariografia. Métodos: estudo prospectivo transversal empacientes internados no Hospital Nossa Senhora da Conceição em Tubarão-SC, nos períodos de novembro de 2006 a abril de 2007. Resultados: A média foi de idade de 62 anos, com predominância do sexo masculino (61,9%). Da amostrade 42 pacientes, 54,8% apresentou angina instável e 45,2%; infarto agudo do miocárdio sem supra de ST. Osfatores de risco prevalentes foram em ordem decrescente de freqüência: hipertensão arterial (78,6%),hereditariedade (57,1%), tabagismo (52,4%), dislipidemia (50%) e diabetes (38,1%). A angina prévia estava presente em 42,8% dos pacientes, o IAM em 33,3% e arevascularização miocárdica prévia em 7,1%. A maioria dos pacientes apresentou o ECG normal (35,7%) e umescore TIMI de alto, moderado e baixo risco respectivamente em 4,7%, 57,1% e 38%. Os medicamentos usados na emergência em ordem decrescente de freqüência foram: Nitrato (89,7%), AAS(87,2%), oxigênio (48,7%) e morfina (37,8%). E durante a internação os resultados foram: AAS (97,6%),clopidogrel (92,8%), nitrato (87,8%), HBPM (85,7%), IECA (78,5%), betabloqueador (54,7%), estatina (52,8%), bloqueador de cálcio (11,9%) e HNF (9,5%). O escore de TIMI foi referido no prontuário de 1 paciente apenas. Conclusão: O escore TIMI foi pouco registrado nos prontuários. A taxa de mortalidade foi inferior àapresentada pela literatura. Os IECA, estatina, o clopidogrel, a heparina e o AAS durante a internação foram bem utilizados enquanto que o AAS na admissão, o betabloqueador e a estatina podem estar sendo subutilizados. Os pacientes de alto risco pelo escoreTIMI receberam atendimento intensivo na UTI mesmo não havendo significância estatística.

Objective: to describe the personal characteristic, clinical treatment, grown to death and correlate TIMI score to ICU internment or transference to the cardiaccatheterization. Methods: Was made transversal study in intern patients of the Nossa Senhora da Conceição Hospital, between November 2006 to April 2007. Results: The mean rate of age was 62 years old, with predominance of male (61,9%). From the sample 42 patients, 54,8% showed UA and 45,2% NSTEMI. The prevalence of risk factor in decrease attendance order were: arterial hypertension (78,6%), heredity (57,1%), abusive smoking ou tabagysm (52,4%),hyperlipidemia (50%), diabetes (38,1%) The previous angine was present in 42,8% of the patients, the IAM in 33,3% and the previous miocardic revascularization in 7,1%. High, moderate and low TIMI score, respectively in 4,7%, 57,1% and 38%. The medicaments used in emergence in decrease attendance order were: Nitrate(89,7%), SAA (87,2%), Oxygen (48,7%), and Morphine (37,8%), During the internment the results were: SAA (97,6%), clopidogrel (92,8%), nitrate (87,8%), LMWH (85,7%), ACEI (78,5%), â blocker (54,7%), statin(52,8%), calcium blocker (11,9%) and HNF (9,5%). Only one patient had reference to TIMI. Conclusion: The TIMI score was little register in the medical record. The mortality rate was lower than showed in the literature. The use of de ACEI, statin, o clopidogrel, heparin and the SAA during the internmentwere used, however SAA in entrance/admission, the â blocker and a statin can be poor available. The patientswith high risk by means of TIMI score received intensive attendance in the UTI service in spite of no statistic significance.

Perfil glicometabólico inicial em pacientes com síndrome coronariana aguda e síndrome metabólica / Perfil glucometabólico inicial en pacientes con síndrome coronario agudo y síndrome metabólico / Early glucometabolic profile in patients with acute coronary syndromes and metabolic syndrome

FUNDAMENTO: Pacientes com síndrome metabólica (SM) têm alto risco coronariano e a disfunção da célula beta ou resistência à insulina pode prever um risco adicional de eventos cardiovasculares precoces. OBJETIVO: Avaliar as alterações glicometabólicas precoces em pacientes com SM, mas sem diagnóstico de diabete tipo 2, após síndrome coronariana aguda. MÉTODOS: Um total de 114 pacientes foi submetido ao teste oral de tolerância à glicose (TOTG), 1-3 dias da alta hospitalar, após infarto agudo do miocárdio ou angina instável. Baseado no TOTG, definimos três grupos de pacientes: tolerância normal à glicose (TNG; n=26), tolerância alterada à glicose (TAG; n=39) ou diabetes mellitus (DM; n=49). O Modelo de Avaliação da Homeostase (HOMA-IR) foi usado para estimar a resistência à insulina; a responsividade da célula beta foi avaliada através do índice insulinogênico de 30 minutos (ΔI30/ΔG30). RESULTADOS: Baseado no HOMA-IR, os pacientes com DM eram mais insulino-resistentes do que aqueles com TNG ou TAG (p<0,001). De acordo com o índice insulinogênico, a responsividade da célula beta também estava alterada em indivíduos com DM (p<0,001 vs TNG ou TAG). CONCLUSÃO: Altas taxas de alterações glicometabólicas foram encontradas após síndrome coronariana aguda em pacientes com SM. Como essas anormalidades acentuadamente aumentam o risco de desfechos adversos, o TOTG precoce pode ser utilizado em pacientes com SM para identificar aqueles que apresentam maior risco coronariano.

BACKGROUND: Patients with metabolic syndrome (MetS) are at high coronary risk and beta-cell dysfunction or insulin resistance might predict an additional risk for early cardiovascular events. OBJECTIVE: This study aimed to evaluate early glucometabolic alterations in patients with MetS, but without previously known type 2 diabetes, after acute coronary syndrome. METHODS: A total of 114 patients were submitted to an oral glucose tolerance test (OGTT) 1-3 days after hospital discharge due to myocardial infarction or unstable angina. Based on the OGTT, we defined three groups of patients: normal glucose tolerance (NGT; n=26), impaired glucose tolerance (IGT; n=39), or diabetes (DM; n=49). The homeostasis model assessment (HOMA-IR) was used to measure insulin resistance; beta-cell responsiveness was assessed by the insulinogenic index at 30 min (ΔI30/ΔG30). RESULTS: Based on the HOMA-IR, patients with DM were more insulin-resistant than those with NGT or IGT (p<0.001). According to the insulinogenic index, the beta-cell responsiveness was also impaired in subjects with DM (p<0.001 vs NGT or IGT). CONCLUSION: High rates of glucometabolic alterations were found after acute coronary syndrome in patients with MetS. As these abnormalities markedly increase the risk for adverse outcomes, early OGTT among MetS patients might be used to identify those at the highest coronary risk.

FUNDAMENTO: Pacientes con síndrome metabólico (SM) tienen alto riesgo coronario y la disfunción de la célula beta o la resistencia a la insulina puede prever un riesgo adicional de eventos cardiovasculares precoces. OBJETIVO: Evaluar las alteraciones glucometabólicas precoces en pacientes con SM, pero sin diagnóstico de diabetes tipo 2, tras el síndrome coronario agudo. MÉTODOS: Un total de 114 pacientes fue sometido a la prueba oral de tolerancia a la glucosa (POTG), de un a tres días tras el alta hospitalaria, y luego de infarto agudo de miocardio o angina inestable. Basado en el POTG, definimos tres grupos de pacientes: tolerancia normal a la glucosa (TNG; n=26), tolerancia alterada a la glucosa (TAG; n=39) o diabetes mellitus (DM; n=49). Se utilizó el Modelo de Evaluación de la Homeostasis (HOMA-IR) para estimarse la resistencia a la insulina; se evaluó la responsividad de la célula beta a través del índice insulinogénico de 30 minutos (ΔI30/ΔG30). RESULTADOS: Basado en el HOMA-IR, los pacientes con DM se mostraban más insulinoresistentes que los individuos con TNG o TAG (p<0,001). De acuerdo con el índice insulinogénico, la responsividad de la célula beta también estaba alterada en individuos con DM (p<0,001 vs. TNG o TAG). CONCLUSIONES: Se encontraron altas tasas de alteraciones glucometabólicas tras el síndrome coronario agudo en pacientes con SM. Como esas anormalidades incrementan acentuadamente el riesgo de desenlaces adversos, el POTG precoz se puede utilizar en pacientes con SM para identificar a los que presentan mayor riesgo coronario.