Echocardiographic prognostication of new onset heart failure in a cohort of ischemic heart disease patients / Pronóstico Ecocardiográfico de un nuevo evento de insuficiencia cardíaca en una cohorte de pacientes con Cardiopatía Isquémica

Background: Echocardiographic predictors for new onset heart failure in patients with ischemic heart disease with reduced left ventricular ejection fraction (HFrEF) or with preserved left ventricular ejection fraction (HFpEF) in Ethiopian and Sub-Saharan African is not well-known.Methods: Two hundred twenty-eight patients with ischemic heart disease were retrospectively recruited and followed. Analysis on baseline clinical and echocardiographic characteristics of patients, and risk factors for new onset HFpEF and new onset HFrEF were done. The exclusion criteria were known heart failure at baseline and those who did not have echocardiography data.Results: During the follow up period, heart failure developed in 62.2% (61/98) of ischemic heart disease patients with preserved left ventricular ejection fraction and in 70.1% (92/130) of ischemic heart disease patients with reduced left ventricular ejection fraction. We did not find significant difference between HFrEF and HFpEF in time to new onset heart failure. Systolic blood pressure, diastolic blood pressure, diabetes, left atrium and diastolic left ventricular dimension had significant association with new onset HFrEF on univariate regression analysis. Whereas new onset HFpEF was significantly associated with age, sex, presence of hypertension, Systolic blood pressure and diastolic left ventricular dimension. On cox regression analysis diastolic left ventricular dimension was associated with both new onset HFpEF and HFrEF. Age, diabetes, and dimension of left atrium were also associated with HFrEF.Conclusion: This cohort study in ischemic heart disease patients suggests a key role for the diastolic left ventricular dimension, left atrium size, diabetes, sex and age as predictors of new onset HFrEF and HFpEF. Strategies directed to prevention and early treatment of diabetes, dilatation of left ventricle and left atrium may prevent a considerable proportion of HFrEF or HFpEF.

Antecedentes: Los predictores ecocardiográficos de nuevos eventos de insuficiencia cardiaca en pacientes con cardiopatía isquémica con fracción de eyección ventricular preservada (HFpEF) o con fracción de eyección ventricular reducida (HFrEF) no son bien conocidos en la Africa etíope y subsahariana.Métodos: Doscientos veintiocho pacientes con cardiopatía isquémica fueron reclutados y seguidos retrospectivamente. Se realizaron análisis sobre las características clínicas y ecocardiográficas basales de los pacientes, así como los factores de riesgo para un nuevo evento de HFpEF y un nuevo evento de HFrEF. Los criterios de exclusión fueron insuficiencia cardíaca conocida al inicio del estudio y aquellos que no tenían datos de ecocardiografía.Resultados: Durante el período de seguimiento, la insuficiencia cardíaca se desarrolló en el 62,2% (61/98) de pacientes con cardiopatía isquémica con fracción de eyección ventricular izquierda preservada y en el 70,1% (92/130) de pacientes con cardiopatía isquémica con fracción de eyección ventricular izquierda reducida. No encontramos diferencias significativas entre HFrEF y HFpEF en el tiempo hasta la nueva aparición de insuficiencia cardíaca. La presión arterial sistólica, la presión arterial diastólica, la diabetes y las dimensiones de la aurícula iquierda y del ventrículo izquierdo en diástole tuvieron una asociación significativa con nuevos eventos de HFrEF en el análisis de regresión univariada. Mientras que un nuevo evento de HFpEF se asoció significativamente con la edad, el sexo, la presencia de hipertensión, la presión arterial sistólica y la dimensión ventricular izquierda diastólica. En el análisis de regresión de cox, la dimensión ventricular izquierda diastólica se asoció con HFpEF de nuevo inicio y HFrEF. La edad, la diabetes y la dimensión de la aurícula izquierda también se asociaron con HFrEF. Conclusión: Este estudio de cohorte en pacientes con cardiopatía isquémica sugiere un papel clave para la dimensión ventricular izquierda diastólica, el tamaño de la aurícula izquierda, la diabetes, el sexo y la edad como predictores de un nuevo evento de HFrEF y HFpEF. Las estrategias dirigidas a la prevención y el tratamiento temprano de la diabetes, la dilatación del ventrículo izquierdo y la aurícula izquierda pueden prevenir una proporción considerable de HFrEF o HFpEF.

Perfil clínico de los pacientes con cardiopatía isquémica y artritis reumatoide. Centro Cardiovascular Regional Centrooccidental / Clinical profile of patients with ischemic heart disease and rheumatoid arthritis. Central Western Regional Cardiovascular Center

La cardiopatía isquémica es la causa más frecuente de morbimortalidad a nivel mundial. La artritis reumatoide (AR) se asocia con el desarrollo prematuro de enfermedades cardiovasculares y la esperanza de vida se reduce principalmente debido a un incremento en la muerte cardiovascular. Se realizó un estudio retrospectivo de revisión de historias médicas con el objetivo de describir el perfil clínico de los pacientes con cardiopatía isquémica y AR que acudieron a la Unidad de Prevención Secundaria y Rehabilitación Cardiovascular del Centro Cardiovascular Regional Centro Occidental desde enero 2013 hasta diciembre 2018. Se incluyeron 37 pacientes con diagnóstico de AR que presentaron algún evento coronario. Ell 62% de los pacientes eran del sexo femenino con una edad media de 59 ± 11 años; el 65% tenían menos de 10 años de diagnóstico de AR. El sedentarismo representó el factor más frecuente (92%), seguido de HTA (76%), tabaquismo (73%), DM (43%), antecedentes familiares de cardiopatía isquémica (24%), obesidad (22%), dislipidemia (16%) y ERC (11%); el tipo de evento coronario más frecuente fue el IMsEST (43%). El análisis multivariado no mostró relación estadísticamente significativa entre número de factores de riesgo y tiempo de duración de la AR con la presencia de lesiones coronarias. El sedentarismo fue el factor de riesgo más frecuente en esta población especial sin embargo el comportamiento de los factores de riesgo tradicionales para cardiopatía isquémica en los pacientes con AR no difiere del de la población general...(AU)

Ischemic heart disease is the most frequent cause of morbidity and mortality worldwide. Rheumatoid arthritis (RA) is associated with premature development of cardiovascular disease and life expectancy is mainly reduced due to an increase in cardiovascular death. A descriptive and retrospective review of medical charts was conducted with the objective of describing the clinical profile of patients with ischemic heart disease and RA who attended the Unidad de Prevención Secundaria y Rehabilitación Cardiovascular del Centro Cardiovascular Regional Centro Occidental from January 2013 to December 2018. 37 patients with RA diagnosis who presented a coronary event were included. The results show that 62% of patients were female with a mean age of 59 ± 11 years; 65% had less than 10 years of diagnosis of RA. Sedentary lifestyle represented the most frequent factor (92%), followed by HTA (76%), smoking (73%), DM (43%), family history of ischemic heart disease (24%), obesity (22%), dyslipidemia (16%) and finally CKD (11%); the most frequent type of coronary event was the IMsEST (43%). The multivariate analysis showed no statistically significant relationship between the number of risk factors and the duration of RA with the presence of coronary lesions. Sedentary lifestyle was the most frequent risk factor in this population however the behavior of traditional risk factors for ischemic heart disease in patients with RA does not differ from the general population...(AU)

Isquemia miocárdica sin lesiones coronarias obstructivas: MINOCA-INOCA: Revisión para la toma de decisiones GREECO (Grupo de Estudio de Enfermedades Coronarias) / Myocardial ischemia without coronary obstructions: MINOCA-INOCA. Review for decision making

Una de cada 4 coronariografías realizadas por isquemia miocárdica presenta lesiones menores al 50% Este dato desencadenó un creciente interés en la comunidad médica. La Sociedad Americana de Cardiología publicó recientemente un artículo que describe la posición consensuada de un grupo de expertos sobre la fisiopatología, el diagnóstico y el tratamiento de esta entidad. Nuestro trabajo refleja una revisión narrativa y la posición de un grupo de expertos pertenecientes a diferentes instituciones con servicios de Cardiología jerarquizados. Aborda aspectos fisiopatológicos y diagnósticos para comprender el enfoque actual del tratamiento, tanto en pacientes que ingresan con diagnóstico de MINOCA (infa rto de miocardio con lesiones angiográficas no graves) o de INOCA (angina e isquemia demostradas, pero sin lesiones coronarias que justifiquen este síndrome).

One in every four coronarographies performed to study myocardial ischemia shows coronary angiographic stenosis less than 50%. This data triggered an increasing interest in the medical community. The American Society of Cardiology recently published a position paper about the pathophysiology, diagnosis and treatment of this entity. Our group performed a narrative review reflecting the opinion of cardiology experts from different centers in Argentina. It aims physiopatologic and diagnostic aspect to understand the current approach in patients with MINOCA (myocardial infarction with non-obstructive coronary arteries) e INOCA (demonstrated angina and ischemia but without coronary lesions that justify this syndrome).

Human pilot study of bare-metal stent: INC-01

ABSTRACT Background: The cost of performing a percutaneous coronary intervention is considerably high for the patient as well as for health systems, which have promoted the development of local technology to help meet the need for these devices. Methods: The INC-01 bare-metal stent was developed at the National Institute of Cardiology in Mexico City and was first implanted on porcine models with technical success in 100% of the evaluated parameters. Presentation of Cases: We present the first three cases of patients with ischemic heart disease, to whom the INC-01 bare-metal stent was implanted. Intracoronary ultrasonography was performed post-stent implantation, showing all the characteristics of implant success during evaluation and clinical follow-up. Conclusions: Angiography and intracoronary ultrasound were carried out demonstrating that the INC-01 bare-metal stent has physical, biological, and histological characteristics similar to those found in commercial metallic stents.

Evaluation of Myocardial Ischemia with iFR (Instantaneous Wave-Free Ratio in the Catheterization Laboratory: A Pilot Study / Avaliação de Isquemia Miocárdica na Sala de Hemodinâmica com iFR Instantaneous Wave-Free Ratio: Estudo Piloto

Abstract Background: The Instantaneous Wave-Free Ratio (iFR) is an invasive functional evaluation method that does not require vasoactive drugs to induce maximum hyperemia Objective: To evaluate the contribution of the iFR to the therapeutic decision-making of coronary lesions in the absence of non-invasive diagnostic methods for ischemia, or in case of discordance between these methods and coronary angiography. Method: We studied patients older than 18 years, of both sexes, consecutively referred for percutaneous treatment between May 2014 and March 2018. Coronary stenotic lesions were classified by visual estimation of the stenosis diameter into moderate (41-70% stenosis) or severe (71%-90%). An iFR ≤ 0.89 was considered positive for ischemia. Logistic regression was performed using the elastic net, with placement of stents as outcome variable, and age, sex, arterial hypertension, diabetes, dyslipidemia, smoking, family history, obesity and acute myocardial infarction (AMI) as independent variables. Classification trees, ROC curves, and Box Plot graphs were constructed using the R software. A p-value < 0.05 was considered statistically significant. Results: Fifty-two patients with 96 stenotic lesions (56 moderate, 40 severe) were evaluated. The iFR cut-off point of 0.87 showed a sensitivity of 0.57 and 1-specificity of 0.88, demonstrating high accuracy in reclassifying the lesions. Diabetes mellitus, dyslipidemia, and presence of moderate lesions with an iFR < 0.87 were predictors of stent implantation. Stents were used in 32% of lesions in patients with stable coronary artery disease and AMI with or without ST elevation (non-culprit lesions). Conclusion: The iFR has an additional value to the therapeutic decision making in moderate and severe coronary stenotic lesions, by contributing to the reclassification of lesions and decreasing the need for stenting.

Resumo Fundamento: Instantaneous Wave-Free Ratio (iFR) é um método de avaliação funcional invasiva sem necessidade de droga vasoativa para indução de hiperemia máxima. Objetivo: Analisar a contribuição do iFR na terapêutica das lesões coronarianas com ausência ou discrepância entre os métodos diagnósticos não invasivos para isquemia e a angiografia coronária. Método: Foram estudados pacientes consecutivos com 18 anos ou mais, ambos os sexos, no período de maio de 2014 a março de 2018, com lesões coronarianas classificadas, por medição da porcentagem de diâmetro da estenose através de estimativa visual, em estenoses moderadas (41-70%) ou graves (71%-90%). O iFR ≤ 0,89 foi considerado positivo para isquemia. Empregou-se regressão logística com elastic net, tendo como variável desfecho o emprego de stent, e variáveis independentes: idade, sexo, hipertensão arterial, diabetes, dislipidemia, tabagismo, história familiar, obesidade e infarto agudo do miocárdio (IAM) prévio. Foram construídas Árvores de Classificação, Curva Roc, e gráficos Box Plot com o software R. O valor de p < 0,05 foi considerado significativo. Resultados: Foram avaliados 52 pacientes com 96 lesões obstrutivas (56 moderadas, 40 graves). O ponto de corte do iFR de 0,87 apresentou sensibilidade de 0,57 e 1-especificidade de 0,88, demonstrando boa acurácia para a reclassificação das lesões. Diabetes mellitus, dislipidemia, e presença de lesão moderada, com iFR < 0,87 foram preditores do implante de stents. Foram empregados stents em 32% das lesões de portadores de doença arterial coronariana estável e IAM com e sem supra de ST (lesões não culpadas). Conclusão: O iFR contribui para a reclassificação das lesões e diminuição do emprego de stents, auxiliando na abordagem das lesões moderadas e severas.

Chest pain score: a novel and practical approach to angina pectoris. A diagnostic accuracy study

ABSTRACT BACKGROUND: The chest pain classifications that are currently in use are based on studies that are several decades old. Various studies have indicated that these classifications are not sufficient for determining the origin of chest pain without additional diagnostic tests or tools. We describe a new chest pain scoring system that examines the relationship between chest pain and ischemic heart disease (IHD). DESIGN AND SETTING: Cross-sectional study conducted in a tertiary-level university hospital and two public hospitals. METHODS: Chest pain scores were assigned to 484 patients. These patients then underwent a treadmill stress test, followed by myocardial perfusion scintigraphy if necessary. Coronary angiography was then carried out on the patients whose tests had been interpreted as positive for ischemia. Afterwards, the relationship between myocardial ischemia and the test score results was investigated. RESULTS: The median chest pain score was 2 (range: 0-7) among the patients without IHD and 6 (1-8) among those with IHD. The median score of patients with IHD was significantly higher than that of patients without IHD (P = 0.001). Receiver operating characteristic analysis showed that the score had sensitivity of 97% and specificity of 87.5% for detecting IHD. CONCLUSION: We developed a pre-test chest pain score that uses a digital scoring system to assess whether or not the pain was caused by IHD. This scoring system can be applied easily and swiftly by healthcare professionals and can prevent the confusion that is caused by other classification and scoring systems.

Study of Myocardial Perfusion in Obese Individuals without Known Ischemic Heart Disease / Estudo de Perfusão Miocárdica em Obesos sem Doença Cardíaca Isquêmica Conhecida

Abstract Background: Obesity is associated with an increased risk of type 2 diabetes mellitus (DM), ischemic heart disease (IHD) and cardiovascular mortality. Several studies have demonstrated the diagnostic and prognostic value of single photon computed tomography-myocardial perfusion scintigraphy (SPECT-MPI) in the evaluation of patients with suspected IHD, including in obese population. Data on clinical risk factors and their association with abnormal myocardial perfusion in obese patients are scarce in the Brazilian population. Objective: To determine the factors associated with abnormal myocardial perfusion in obese individuals without known IHD. Methods: We studied obese patients without known IHD who were referred for evaluation through SPECT-MPI between January 2011 and December 2016. Clinical variables and results of SPECT-MPI were obtained systematically. The distribution of continuous variables was assessed using the Shapiro-Wilk and Shapiro-Francia tests. We used the unpaired Student t test to compare the means of continuous variables with normal distribution and the Chi Square test for binomial variables analysis. A p value < 0.05 was considered statistically significant. The association of the clinical variables for the presence of factors associated with abnormal myocardial perfusion was determined by univariate and multivariate logistic regression analysis, and respective odds ratios (OR) and 95% confidence intervals (CI). Results: The study sample consisted of 5,526 obese patients. Mean body mass index (BMI) of our patients was 33.9 ± 3.7 kg/m2, 31% had DM, and myocardial perfusion abnormalities was observed in 23% of the total sample. The factors associated with abnormal myocardial perfusion on multivariate analysis were: age (OR: 1.02, 95% CI 1.01-1.03, p < 0.001), DM (OR: 1.57, 95% CI 1.31-1.88, p < 0.001), typical angina before the test (OR: 2.45, 95% CI: 1.82-3.31, p < 0.001), need for pharmacologic stress test (OR: 1.61, 95% CI: 1.26-2.07, p < 0.001), less physical effort evaluated in metabolic equivalents (METs) during the exercise treadmill test (OR: 0.89, 95% CI: 0.85-0.94, p < 0.001) and a lower post-stress left ventricular ejection fraction after stress (LVEF; OR: 0.989, 95% CI: 0.984-0.994, p < 0.001). Conclusion: The factors associated with abnormal myocardial perfusion in obese patients without known IHD were age, DM, presence of typical angina, ventricular dysfunction, and inability to undergo physical stress as clinical variables, in addition to functional capacity during physical stress.

Resumo Fundamento: A obesidade associa-se a um risco aumentado de diabetes mellitus do tipo 2 (DM), doença cardíaca isquêmica (DCI) e mortalidade cardiovascular. Vários estudos demonstraram o valor diagnóstico e prognóstico da cintilografia de perfusão miocárdica com tomografia computadorizada por fóton único (CPM-SPECT) na avaliação de pacientes com suspeita de DCI, inclusive na população de obesos. Dados sobre fatores de risco clínicos, e sua associação com perfusão miocárdica anormal em obesos, são escassos na população brasileira. Objetivo: Determinar quais são os fatores associados à anormalidade de perfusão miocárdica em obesos sem DCI conhecida. Métodos: Estudamos pacientes obesos sem DCI conhecida que foram encaminhados para avaliação por CPM-SPECT entre janeiro de 2011 até dezembro de 2016. Variáveis clínicas e resultados da CPM-SPECT foram obtidos de forma sistematizada. A distribuição das variáveis contínuas foi avaliada utilizando-se os testes de Shapiro-Wilk e Shapiro-Francia. Utilizou-se o teste t de Student não pareado para comparar as médias das variáveis contínuas com distribuição normal, e o teste do Chi quadrado para análise das variáveis binomiais. Considerou-se o valor de p < 0,05 como estatisticamente significativo. A associação das variáveis clínicas para a presença de anormalidade de perfusão miocárdica foi determinada por análise de regressão logística univariada e multivariada, calculando-se e apresentando-se os respectivos odds ratios (OR) e intervalos de confiança (IC) de 95. Resultados: A amostra do estudo foi de 5.526 pacientes obesos. O índice de massa corporal médio dos nossos pacientes foi de 33,9 ± 3,7 kg/m2, 31% eram portadores de DM, e anormalidades de perfusão foram observadas em 23% do total da amostra. Os fatores associados à anormalidade de perfusão miocárdica, após análise multivariada, foram: idade (OR: 1,02, IC 95%: 1,01-1,03, p < 0,001), DM (OR: 1,57, IC 95%: 1,31-1,88, p < 0,001), presença de angina típica antes do exame (OR: 2,45, IC 95%: 1,82-3,31, p < 0,001), necessidade de utilização de protocolo com estresse farmacológico (OR: 1,61, IC 95%: 1,26-2,07, p < 0,001), menor esforço físico avaliado em equivalentes metabólicos durante o teste ergométrico (OR: 0,89, IC 95%: 0,85-0,94, p < 0,001) e menor fração de ejeção do ventrículo esquerdo após estresse (OR: 0,989, IC 95%: 0,984-0,994, p < 0,001). Conclusão: Os fatores associados à anormalidade de perfusão miocárdica em pacientes obesos sem DCI conhecida foram idade, DM, presença de angina típica, disfunção ventricular e incapacidade para o estresse físico como variáveis clínicas, além da capacidade funcional durante o estresse físico.

Diabetes mellitus tipo 2 y cardiopatía isquémica: fisiopatología, regulación génica y futuras opciones terapéuticas / Type II diabetes and ischemic heart disease: pathophysiology, gen regulation and future therapeutic options

Resumen: En los últimos años, la diabetes mellitus tipo 2 (DM2) ha evolucionado en forma epidémica, experimentando un rápido crecimiento y afectando a millones de individuos a nivel mundial. La cardiopatía isquémica es la principal causa de mortalidad en los pacientes diabéticos, quienes poseen un mayor riesgo cardiovascular respecto a los no diabéticos. La DM2 y la cardiopatía isquémica se caracterizan por ser prevenibles, sin embargo, existen diversos factores de riesgo comunes que contribuyen a su desarrollo. Los mecanismos que explican la ateroesclerosis acelerada y el incremento de riesgo de enfermedades cardiovasculares en los pacientes diabéticos tipo 2 incluyen a la hiperglicemia, dislipidemia y la inflamación del endotelio vascular. La diabetes es resultado de una interacción compleja entre la genética y el medio ambiente. Recientemente se han descrito varios genes implicados en el desarrollo de la diabetes y cardiopatía isquémica y que podrían significar nuevas opciones terapéuticas. En este artículo se revisa la relación entre ambas patologías, los mecanismos moleculares y el descubrimiento de factores de riesgo genéticos comunes y su implicancia en el desarrollo de nuevos blancos terapéuticos.

Abstracts: In recent years, type 2 diabetes mellitus has evolved as a rapidly increasing epidemic and affects millions of people worldwide. Ischemic heart disease (IHD) is the main cause of death among diabetic patients, who have a higher cardiovascular risk than non-diabetics. Both, DM2 and IHD are characterized by being preventable, however there are several common risk factors that contribute to their development. The mechanisms that explain accelerated atherosclerosis and increased risk of cardiovascular diseases in patients with type 2 diabetes mellitus include damage by hyperglycemia, dyslipidemia and inflammation on vascular endothelium. Diabetes is the result of a complex interaction between genetics and the environment, recently, several genes have been identified that appear to be involved in diabetes and ischemic heart disease that could explain its relationship and serve as new therapeutic possibilities. In this article, we review the relationship between diabetes and ischemic heart disease, the molecular mechanisms and the discovery of genetic risk factors common to both diseases and their implication in the development of new therapeutic targets.

A possible relationship between gluconeogenesis and glycogen metabolism in rabbits during myocardial ischemia

ABSTRACT Ischemia is responsible for many metabolic abnormalities in the heart, causing changes in organ function. One of modifications occurring in the ischemic cell is changing from aerobic to anaerobic metabolism. This change causes the predominance of the use of carbohydrates as an energy substrate instead of lipids. In this case, the glycogen is essential to the maintenance of heart energy intake, being an important reserve to resist the stress caused by hypoxia, using glycolysis and lactic acid fermentation. In order to study the glucose anaerobic pathways utilization and understand the metabolic adaptations, New Zealand white rabbits were subjected to ischemia caused by Inflow occlusion technique. The animals were monitored during surgery by pH and lactate levels. Transcription analysis of the pyruvate kinase, lactate dehydrogenase and phosphoenolpyruvate carboxykinase enzymes were performed by qRT-PCR, and glycogen quantification was determined enzymatically. Pyruvate kinase transcription increased during ischemia, followed by glycogen consumption content. The gluconeogenesis increased in control and ischemia moments, suggesting a relationship between gluconeogenesis and glycogen metabolism. This result shows the significant contribution of these substrates in the organ energy supply and demonstrates the capacity of the heart to adapt the metabolism after this injury, sustaining the homeostasis during short-term myocardial ischemia.

Abnormal diastolic function underlies the different beneficial effects of cardiac resynchronization therapy on ischemic and non-ischemic cardiomyopathy

OBJECTIVES: To investigate the association between diastolic function and the different beneficial effects of cardiac resynchronization therapy in patients with heart failure due to different causes. METHODS: The 104 enrolled patients were divided into an ischemic cardiomyopathy group (n=27) and a non-ischemic cardiomyopathy group (n=77) according to the cause of heart failure. Before implantation, left ventricular diastolic function was evaluated in all patients using echocardiography. After six months of follow-up, the beneficial effects of cardiac resynchronization therapy were evaluated using a combination of clinical symptoms and echocardiography parameters. RESULTS: The ischemic cardiomyopathy group included significantly more patients with restrictive filling than the non-ischemic cardiomyopathy group. The response rate after the implantation procedure was significantly higher in the non-ischemic cardiomyopathy group than in the ischemic cardiomyopathy group. Degrees of improvement in echocardiography parameters were significantly greater in the non-ischemic cardiomyopathy group than in the ischemic cardiomyopathy group. Multivariate regression analysis showed that a restrictive filling pattern was an independent factor that influenced responses to cardiac resynchronization therapy. CONCLUSIONS: This study again confirmed that the etiology of heart failure affects the beneficial effects of cardiac resynchronization therapy and a lower degree of improvement in ventricular systolic function and remodelling was observed in ischemic cardiomyopathy patients than in non-ischemic cardiomyopathy patients. In addition, systolic heart failure patients with severe diastolic dysfunction had poor responses to cardiac resynchronization therapy. Ischemic cardiomyopathy patients exhibited more severe diastolic dysfunction than non-ischemic cardiomyopathy patients, which may be a reason for the reduced beneficial effect of cardiac resynchronization therapy.

Tortuosidade Coronariana e seu Papel na Isquemia Miocárdica em Pacientes sem Obstruções Coronarianas / Coronary tortuosity and its role in myocardial ischemia in patients with no coronary obstructions

Este trabalho faz uma revisão sobre o tema de tortuosidade coronariana abordando várias situações na prática clínica aonde a tortuosidade coronariana pode desempenhar um papel relevante e procura avaliar se há correlação entre tortuosidade coronariana e a presença de isquemia miocárdica em pacientes sem obstruções coronarianas fazendo uma busca na literatura das evidências científicas. Livro-texto de Fisiologia em Cardiologia com estudo da circulação coronariana, artigos teóricos com estudos de Hemodinâmica, Dinâmica de Fluidos e de Mecânica e artigos experimentais com simulação em computadores serviram de sustentação para a formulação da hipótese a ser verificada

Effects of Nitrate Intake on Myocardial Ischemia-Reperfusion Injury in Diabetic Rats / Efeitos do Consumo de Nitrato na Lesão de Isquemia-Reperfusão Miocárdica em Ratos Diabéticos

Abstract Background: Coronary artery disease is 2-3 times more common in diabetic individuals. Dietary nitrate/nitrite has beneficial effects in both diabetes and cardiovascular disease. It also has protective effects against myocardial ischemia-reperfusion (IR) injury in healthy animals. However, the effects of nitrate on myocardial IR injury in diabetic rats have not yet been investigated. Objective: We examined the effects of dietary nitrate on myocardial IR injury in streptozotocin-nicotinamide-induced diabetic rats. Method: Rats were divided into four groups (n=7 in each group): control, control+nitrate, diabetes, and diabetes+nitrate. Type 2 diabetes was induced by injection of streptozotocin and nicotinamide. Nitrate (sodium nitrate) was added to drinking water (100 mg/L) for 2 months. The hearts were perfused in a Langendorff apparatus at 2 months and assessed before (baseline) and after myocardial IR for the following parameters: left ventricular developed pressure (LVDP), minimum and maximum rates of pressure change in the left ventricle (±dP/dt), endothelial nitric oxide (NO) synthase (eNOS) and inducible NO synthase (iNOS) mRNA expression, and levels of malondialdehyde (MDA) and NO metabolites (NOx). Results: Recovery of LVDP and ±dP/dt was lower in diabetic rats versus controls, but almost normalized after nitrate intake. Diabetic rats had lower eNOS and higher iNOS expression both at baseline and after IR, and dietary nitrate restored these parameters to normal values after IR. Compared with controls, heart NOx level was lower in diabetic rats at baseline but was higher after IR. Diabetic rats had higher MDA levels both at baseline and after IR, which along with heart NOx levels decreased following nitrate intake. Conclusion: Dietary nitrate in diabetic rats provides cardioprotection against IR injury by regulating eNOS and iNOS expression and inhibiting lipid peroxidation in the heart.

Resumo Fundamentos: A doença arterial coronariana é duas a três vezes mais comum em indivíduos diabéticos. O nitrato/nitrito dietético tem efeitos benéficos tanto para o diabetes quanto para a doença cardiovascular, assim como efeitos protetores contra a lesão de isquemia-reperfusão (IR) miocárdica em animais saudáveis. Porém, os efeitos do nitrato na lesão de IR miocárdica em ratos diabéticos ainda não foram investigados. Objetivos: Foram examinados os efeitos sobre a lesão de IR miocárdica da adição de nitrato à dieta de ratos com diabetes mellitus tipo 2 induzido por estreptozotocina-nicotinamida. Métodos: Os ratos foram divididos em quatro grupos (n = 7 em cada grupo): controle, controle+nitrato, diabetes e diabetes+nitrato. O diabetes foi induzido nos animais por injeção de estreptozotocina e nicotinamida. Nitrato (nitrato de sódio) foi adicionado à água de beber (100 mg/L) por 2 meses. Os corações foram perfundidos em sistema de Langendorff aos 2 meses e avaliados antes (basal) e após IR miocárdica em relação aos seguintes parâmetros: pressão desenvolvida no ventrículo esquerdo (PDVE), taxas máximas de variação positiva e negativa da pressão ventricular esquerda (±dP/dt), expressão do RNAm da óxido nítrico (NO) sintase (NOS) endotelial (eNOS) e da NOS induzível (iNOS), além de níveis de malondialdeído (MDA) e metabólitos do óxido nítrico (NOx). Resultados: A recuperação da PDVE e ±dP/dt foi inferior nos ratos diabéticos versus controles, mas quase normalizou após ingestão de nitrato. Ratos diabéticos apresentaram expressão diminuída de eNOS e aumentada de iNOS tanto no estado basal quanto após IR, e o consumo dietético de nitrato restaurou estes valores para o estado normal após a IR. O nível de NOx cardíaco foi menor nos ratos diabéticos em comparação aos controles no momento basal, mas foi superior após a IR. Ratos diabéticos apresentaram níveis mais elevados de MDA tanto no estado basal quanto após IR que, juntamente com os níveis cardíacos de NOx, reduziram após consumo dietético do nitrato. Conclusões: O consumo dietético de nitrato por ratos diabéticos ofereceu cardioproteção contra a lesão de IR através da regulação da expressão de eNOS e iNOS e inibição da peroxidação lipídica no coração.

Cardiac Regeneration using Growth Factors: Advances and Challenges / Regeneração Cardíaca com Fatores de Crescimento: Avanços e Desafios

Abstract Myocardial infarction is the most significant manifestation of ischemic heart disease and is associated with high morbidity and mortality. Novel strategies targeting at regenerating the injured myocardium have been investigated, including gene therapy, cell therapy, and the use of growth factors. Growth factor therapy has aroused interest in cardiovascular medicine because of the regeneration mechanisms induced by these biomolecules, including angiogenesis, extracellular matrix remodeling, cardiomyocyte proliferation, stem-cell recruitment, and others. Together, these mechanisms promote myocardial repair and improvement of the cardiac function. This review aims to address the strategic role of growth factor therapy in cardiac regeneration, considering its innovative and multifactorial character in myocardial repair after ischemic injury. Different issues will be discussed, with emphasis on the regeneration mechanisms as a potential therapeutic resource mediated by growth factors, and the challenges to make these proteins therapeutically viable in the field of cardiology and regenerative medicine.

Resumo O infarto do miocárdio representa a manifestação mais significativa da cardiopatia isquêmica e está associado a elevada morbimortalidade. Novas estratégias vêm sendo investigadas com o intuito de regenerar o miocárdio lesionado, incluindo a terapia gênica, a terapia celular e a utilização de fatores de crescimento. A terapia com fatores de crescimento despertou interesse em medicina cardiovascular, devido aos mecanismos de regeneração induzidos por essas biomoléculas, incluindo angiogênese, remodelamento da matriz extracelular, proliferação de cardiomiócitos e recrutamento de células-tronco, dentre outros. Em conjunto, tais mecanismos promovem a reparação do miocárdio e a melhora da função cardíaca. Esta revisão pretende abordar o papel estratégico da terapia, com fatores de crescimento, para a regeneração cardíaca, considerando seu caráter inovador e multifatorial sobre o reparo do miocárdio após dano isquêmico. Diferentes questões serão discutidas, destacando-se os mecanismos de regeneração como recurso terapêutico potencial mediado por fatores de crescimento e os desafios para tornar essas proteínas terapeuticamente viáveis no âmbito da cardiologia e da medicina regenerativa.

Sevoflurane preconditioning during myocardial ischemia-reperfusion reduces infarct size and preserves autonomic control of circulation in rats

ABSTRACT PURPOSE: To investigate the myocardial ischemia-reperfusion with sevoflurane anesthetic preconditioning (APC) would present beneficial effects on autonomic and cardiac function indexes after the acute phase of a myocardial ischemia-reperfusion. METHODS: Twenty Wistar rats were allocated in three groups: control (CON, n=10), myocardial infarction with sevoflurane (SEV, n=5) and infarcted without sevoflurane (INF, n=5). Myocardial ischemia (60 min) and reperfusion were performed by temporary coronary occlusion. Twenty-one days later, the systolic and diastolic function were evaluated by echocardiography; spectral analysis of the systolic arterial pressure (SAPV) and heart rate variability (HRV) were assessed. After the recording period, the infarct size (IS) was evaluated. RESULTS: The INF group presented greater cardiac dysfunction and increased sympathetic modulation of the SAPV, as well as decreased alpha index and worse vagal modulation of the HRV. The SEV group exhibited attenuation of the systolic and diastolic dysfunction and preserved vagal modulation (square root of the mean squared differences of successive R-R intervals and high frequency) of HRV, as well as a smaller IS. CONCLUSION: Sevoflurane preconditioning better preserved the cardiac function and autonomic modulation of the heart in post-acute myocardial infarction period.

Sensibilidade e Especificidade da Albumina Modificada pela Isquemia em Ratos Wistar / Sensitivity and Specificity of Ischemia Modified Albumin in Wistar Rats

O infarto agudo do miocárdio (IAM) é uma situação clínica determinada por processo isquêmicoagudo, que resulta em necrose miocárdica. Os marcadores cardíacos em caso de isquemia reversível, atualmente,apresentam sensibilidade limitada.Objetivo: Verificar a sensibilidade da albumina modificada isquêmica (AMI), como marcador cardíaco. Métodos: Estudo experimental, realizado no Laboratório de Experimentação Animal da Universidade Regional Integrada (URI), Erechim, RS, no período de 2011 a 2013. Após a indução isquêmica do miocárdio em ratos da linhagem Wistar-Tecpar, com idade aproximada entre 60-90 dias, através da administração de isoproterenol hidrocloridrato, o conteúdo da AMI foi avaliado em diferentes tempos. Resultados: Os valores da AMI mantiveram-se diminuídos durante as três horas iniciais, após a indução isquêmica pelo isoproterenol hidrocloridrato. Conclusão: Neste estudo, a albumina modificada pela isquemia foi considerada um marcador sensível,principalmente nas três horas iniciais da isquemia...

Background: Acute myocardial infarction (AMI) is a condition determined by an acute ischemic process resulting in myocardial necrosis. Cardiac markers in reversible ischemia currently have limited sensitivity. Objective: To check the sensitivity of ischemia modified albumin (IMA) as a cardiac marker.Methods: Experimental study held at the Animal Experimentation Laboratory of Universidade Regional Integrada (URI), Erechim, RS, from 2011 to 2013. After myocardial ischemic induction in Wistar-Tecpar rats aged about 60-90 days through administration of isoproterenol hydrochloride, the IMA content was evaluated at different times. Results: The IMA values remained reduced during the three first hours after ischemic induction by isoproterenol hydrochloride.Conclusion: In this study, ischemia modified albumin was considered a sensitive marker, particularly in the first three hours of ischemia...

Isquemia miocárdica extensa em mulher jovem com lúpus eritematoso sistêmico / Extensive myocardial ischemia among young woman with systemic lupus erythematosus

Paciente do sexo feminino, 24 anos, diagnosticada há seis anos com lúpus eritematoso sistêmico, apresentou dispneia aos médios esforços após quadro depré-eclampsia e edema agudo de pulmão. Foi realizada ecocardiografia que revelou trombo intracavitário no VEe discinesia, necessitando de internação para anticoagulação. A cintilografia tomográfica de perfusão miocárdica com 99mTc-sestamibi revelou defeitos de perfusão miocárdica compatíveis com área de isquemia estimada em 12 %. Discutem-se neste relato os aspectos clínicos das complicações cardiovasculares do lúpus eritematoso sistêmico.

Female patient, 24 years old, diagnosed six years ago with systemic lupus erythematosus, presented dyspnea on moderate exertion after preeclampsia and acute lung edema. Echocardiography disclosed an intracavitary thrombus in the LV with dyskinesia,requiring hospitalization for anticoagulation. Myocardial perfusion SPECT showed 99Tcm-sestamibi myocardial perfusion defects compatible with an area of ischemia estimated at 12%. This report discusses clinical aspects of cardiovascular complications resulting from systemic lúpus erythematous.