Association of Inflammation and Endothelial Dysfunction with Coronary Microvascular Resistance in Patients with Cardiac Syndrome X / Associação de Inflamação e Disfunção Endotelial com Resistência Microvascular Coronariana em Pacientes com Síndrome Cardíaca X

Abstract Background: Although a proportion of CSX patients have impaired brachial artery flow-mediated dilatation (FMD) in response to hyperemia, suggesting that endothelial dysfunction in these patients may be systemic and not just confined to the coronary circulation; the underlying mechanisms triggering endothelial dysfunction in these patients are still incompletely understood. Objectives: To assess the association of the index of Microcirculatory Resistance (IMR) with endothelial dysfunction and inflammation in patients with CSX. Methods: We studied 20 CSX patients and 20 age and gender-matched control subjects. Thermodilution-derived coronary flow reserve (CFR) and IMR were measured using a pressure-temperature sensor-tipped guidewire. Brachial artery FMD was measured using high-resolution, two-dimensional ultrasound images obtained with a Doppler ultrasound device (HDI-ATL 5000, USA) with a 5 MHz to 12 MHz linear-array transducer. Results: Compared with in control subjects, CFR was significantly lower (2.42 ± 0.78 vs. 3.59 ± 0.79, p < 0.001); IMR was higher (32.2 ± 8.0 vs. 19.5 ± 5.5, p < 0.001); the concentration of hs-CRP and FMD was higher (4.75 ± 1.62 vs. 2.75 ± 1.50; 5.24 ± 2.41 vs. 8.57 ± 2.46, p < 0.001) in CSX patients. The Duke treadmill score (DTS) was correlated positively to CFR and FMD (0.489 and 0.661, p < 0.001), it was negative to IMR and hsCRP (-0.761 and -0.087, p < 0.001) in CSX patients. Conclusions: The main finding in this study is that the DTS measured in patients with CSX was associated to hsCRP and FMD. Moreover, the independent effects of exercise tolerance can significantly impair FMD and hsCRP in CSX patients; especially it is particularly important to whom where FMD was associated negatively with IMR.

Resumo Fundamentos: Embora uma proporção de pacientes com SCX tenha dilatação mediada por fluxo da artéria braquial (DMF) prejudicada em resposta à hiperemia, sugerindo que a disfunção endotelial nestes pacientes pode ser sistémica e não limitar-se à circulação coronariana, os mecanismos subjacentes que desencadeiam a disfunção endotelial nestes pacientes ainda não são completamente compreendidos. Objetivos: Avaliar a associação do índice de resistência microcirculatória (IMR) com a disfunção endotelial e a inflamação em pacientes com SCX. Métodos: Estudaram-se 20 pacientes com SCX e 20 sujeitos de controle emparelhados em idade e género. A reserva de fluxo coronariano derivada da termodiluição (RFC) e a IMR forma medidas usando um fio guia com ponta de sensor de temperatura e pressão. A DMF da artéria braquial foi medida utilizando imagens ultrassónicas bidimensionais de alta resolução obtidas com um aparelho de ultrassom Doppler (HDI-ATL 5000, EE.UU.) com transdutor linear de 5 MHz a 12 MHz. Resultados: Em comparação com os sujeitos de controle, a RFC foi significativamente menor (2,42 ± 0,78 vs 3,59 ± 0,79, p < 0,001); o IMR foi maior (32,2 ± 8,0 frente a 19,5 ± 5,5, p < 0,001); a concentração de PCR-as e DMF foi maior (4,75 ± 1,62 frente a 2,75 ± 1,50, 5,24 ± 2,41 diante de 8,57 ± 2,46, p < 0,001) em pacientes com SCX. A escore de Duke (ED) se correlacionou positivamente com RFC e DMF (0,489 e 0,661, p < 0,001), foi negativa para IMR e PCR-as (-0,761 e -0,087, p < 0,001) em pacientes com SCX. Conclusões: O principal achado neste estudo é que o ED medido em pacientes com SCX esteve associado a PCR-as e DMF. Por outra parte, os efeitos independentes da tolerância ao exercício podem piorar significativamente a DMF e a PCR-as em pacientes com SCX especialmente, é particularmente importante que a DMF se associou negativamente com a RIM.

Disfunção coronariana microvascular / Coronary Microvascular Dysfunction

Nas duas últimas décadas, uma série de estudos relatou que as anormalidades na função e estrutura da microcirculação coronariana podem ocorrer em pacientes sem aterosclerose obstrutiva, em pacientes com fatores de risco, com doenças do miocárdio, bem como na aterosclerose obstrutiva. A disfunção microvascular coronariana pode ser iatrogênica e é importante marcador de risco, contribuindo para a patogênese de doenças cardiovasculares e do miocárdio. Devido a sua importância torna-se alvo terapêutico. Este artigo apresenta uma atualização sobre a relevância clínica da disfunção microvascular coronariana em diferentes situações clínicas.

In the last two decades, a number of studies reported that abnormalities in the coronary microcirculation function and structure may occur in patients without obstructive atherosclerosis, in patients with risk factors, with myocardial diseases, as well as inobstructive atherosclerosis. Coronary microvascular coronary dysfunction may be iatrogenic and is an important risk marker, contributing to the pathogenesis of cardiovascular and myocardial diseases. Due to its importance, it becomes a therapeutic target.This article presents an update on the clinical relevance of coronary microvascular dysfunction in different clinical situations.

Alteración del sodio y potasio en pacientes hospitalizados por insuficiencia cardíaca / Alteration of sodium and potassium levels in patients hospitalized for heart failure

La insuficiencia cardíaca es un síndrome ocasionado por múltiples factores y va produciendo un proceso de remodelado ventricular. Es un verdadero problema de salud pública que incrementa el número de hospitalizaciones. Los diuréticos siguen siendo útiles en el tratamiento, aún así se producen alteraciones de los electrólitos que pueden ocasionar arritmias, empeoramiento de la insuficiencia cardíaca y disminución de la fracción de eyección. Este trabajo evalúa la alteración del sodio y potasio en pacientes hospitalizados por este síndrome. Se revisaron las historias de pacientes con insuficiencia cardíaca ingresados al servicio de Cardiología, registrando datos en base a un protocolo. Se revisaron 33 historias de las cuales 11 pacientes eran mujeres y 22 eran hombres, con un promedio de edad de 72,64 y 71,52 años respectivamente. Días de hospitalización promedio de 14,91 días. Todos los pacientes tenían dieta hiposódica excepto uno debido a diarrea. El 57,6% tenían una sola patología y el resto dos o tres. La hipertensión arterial es la patología más frecuente en un 81,8%, seguido de cardiopatía isquémica en un 30,3%. Recibieron tres diuréticos (furosemida, espirolactona, hidroclorotiazida) el 48,5% de los pacientes y dos diuréticos el 48,5%. El 51,5% de los pacientes tenían potasio bajo y el 57,6% sodio bajo. En un 50% de los pacientes se encuentra que el potasio y sodio están bajos que se relaciona con el uso de diuréticos y una dieta hiposódica. Habría que considerar el uso de suplemento de potasio en estos casos.

Heart failure a syndrome caused by multiple factors engenders a process of ventricular remodeling. It is an enormous public health problem, with an increasing number of hospitalizations. Diuretics, still useful for treatment, produce electrolyte abnormalities can cause arrhythmias, worsening heart failure and larger reduction in the ejection fraction. This study evaluated the alteration of sodium and potassium levels in patients hospitalized with this syndrome. We reviewed the charts of patients with heart failure admitted to the cardiology service, recording data with the use of a standardized form. We reviewed 33 records for 11 women and 22 men with a mean age of 72.64 and 71.52 years respectively. The average number of days of hospitalization was 14.91 days. All patients had a low sodium diet except one because of diarrhea. A single pathology was present in 57.6% with the rest having two or three. Hypertensión was the most frequent pathology in 81.8% , followed by ischemic heart disease in 30.3%. Three diuretics (furosemide, spironolactone, hydrochlorothiazide) were used in 48.5% of patients and two diuretics in 48.5%. In 51.5 of patients there was low potassium and in 57.6% low sodium. Potassium and sodium were low in 50% of patients, which was associated with the use of diuretics and a low salt diet. Potassium supplements should be considered in these cases.

Study of the pathophysiological mechanism in patients with typical chest pain and normal coronary arteries

Endothehelial dysfunction. thrombogenesis and inflammation were studied as possible mechanisms in pathogertesis of cardic syndrome-X through monitoring plasma endothelin-1 fibrinogen, vWF and CRP in patients with typical chest pain, positive stress ECG[clinical and ECG evidence of ischemia] and normal coronary angiography. The aim of this study is to evaluate plasma concentration of enclothelin-1 and other factors in patients with typical angina pectoris and angiographically normal coronary arteries. This study included 50 patients complained of typical chest pain [group A], Another group of 20 healthy subjects were studied as control group [group B]. Exercise test and coronary angiography were performed for all patients. Patients showing positive exercise ECG and having normal coronary arteries were selected. Blood samples were collected and examined for endothelin-1, fibrinogen, CRP and vWF. Endotheline-l fibrinogen, CRP and vWF were found to be significantly raised in that group of patients with syndrome-X in comparison with the control group, so they could predict and confirm diagnosis in patients with syndrome-X. CRP, vWF fibrinogen and ET-1 in that order were significantly high in patients with syndrome-X. Thus assessment of their levels in serum may be highly needed to fulfill the diagnosis of cardiac syndrome-X

Dolor Torácico con Arterias Coronarias Normales, Angina Microvascular o Síndrome X Cardiológico

La presencia de dolor torácico anginoso en pacientes con angiografía coronaria normal ha despertado gran interés en los últimos años. Las investigaciones sugieren que el dolor torácico es de origen multifactorial, puede ser secundario a alteraciones de la microcirculación coronaria, hiperinsulinemia, disfunción endotelial e isquemia cardíaca y/o a transtornos de la sensibilidad al dolor; éste puede ser inducido por múltiples estímulos (liberación de adenosina, manipulación de catéteres intracardíacos, distensión del esófago, estimulación eléctrica de la piel, etc). Además del compromiso vascular coronario, se ha demostrado compromiso del músculo liso vascular del antebrazo, músculo liso bronquial y músculo esofágico. Con frecuencia se observa una disminución de la de expulsión durante el ejercicio, usualmente en los pacientes con electrocardiogramas anormales durante la prueba de esfuerzo. El enfoque diagnóstico y diferentes opciones terapéuticas son revisadas