RESUMEN

The presence of cardiac shunts in ectothermic tetrapods is thought to be consistent with active vascular modulations for proper hemodynamic support. Local control of blood flow modulates tissue perfusion and thus systemic conductance (Gsys) is assumed to increase with body temperature (Tb) to accommodate higher aerobic demand. However, the general increase of Gsys presses for a higher right-to-left (R-L) shunt, which reduces arterial oxygen concentration. In contrast, Tb reduction leads to a Gsys decrease and a left-to-right shunt, which purportedly increases pulmonary perfusion and plasma filtration in the respiratory area. This investigation addressed the role of compensatory vascular adjustments in the face of the metabolic alterations caused by Tb change in the South American rattlesnake (Crotalus durissus). Cardiovascular recordings were performed in decerebrated rattlesnake preparations at 10, 20 and 30°C. The rise in Tb increased metabolic demand, and correlated with an augmentation in heart rate. Although cardiac output increased, systemic stroke volume reduced while pulmonary stroke volume remained stable. Although that resulted in a proportionally higher increase in pulmonary blood flow, the R-L shunt was maintained. While the systemic compliance of large arteries was the most relevant factor in regulating arterial systemic blood pressure, peripheral conductance of pulmonary circulation was the major factor influencing the final cardiac shunt. Such dynamic adjustment of systemic compliance and pulmonary resistance for shunt modulation has not been demonstrated before and contrasts with previous knowledge on shunt control.

Asunto(s)

RESUMEN

Purinergic signaling is a crucial determinant in the regulation of pulmonary vascular physiology and presents a promising avenue for addressing lung diseases. This intricate signaling system encompasses two primary receptor classes: P1 and P2 receptors. P1 receptors selectively bind adenosine, while P2 receptors exhibit an affinity for ATP, ADP, UTP, and UDP. Functionally, P1 receptors are associated with vasodilation, while P2 receptors mediate vasoconstriction, particularly in basally relaxed vessels, through modulation of intracellular Ca2+ levels. The P2X subtype receptors facilitate extracellular Ca2+ influx, while the P2Y subtype receptors are linked to endoplasmic reticulum Ca2+ release. Notably, the primary receptor responsible for ATP-induced vasoconstriction is P2X1, with α,ß-meATP and UDP being identified as potent vasoconstrictor agonists. Interestingly, ATP has been shown to induce endothelium-dependent vasodilation in pre-constricted vessels, associated with nitric oxide (NO) release. In the context of P1 receptors, adenosine stimulation of pulmonary vessels has been unequivocally demonstrated to induce vasodilation, with a clear dependency on the A2B receptor, as evidenced in studies involving guinea pigs and rats. Importantly, evidence strongly suggests that this vasodilation occurs independently of endothelium-mediated mechanisms. Furthermore, studies have revealed variations in the expression of purinergic receptors across different vessel sizes, with reports indicating notably higher expression of P2Y1, P2Y2, and P2Y4 receptors in small pulmonary arteries. While the existing evidence in this area is still emerging, it underscores the urgent need for a comprehensive examination of the specific characteristics of purinergic signaling in the regulation of pulmonary vascular tone, particularly focusing on the disparities observed across different intrapulmonary vessel sizes. Consequently, this review aims to meticulously explore the current evidence regarding the role of purinergic signaling in pulmonary vascular tone regulation, with a specific emphasis on the variations observed in intrapulmonary vessel sizes. This endeavor is critical, as purinergic signaling holds substantial promise in the modulation of vascular tone and in the proactive prevention and treatment of pulmonary vascular diseases.

RESUMEN

Since the discovery of right ventricular infarction, interest in the characteristics of the right ventricle has been increasing. Right ventricular function is now known to be a predictor of mortality in different settings. The right ventricle is a low-pressure, high-compliance, high-volume chamber. To carry out its normal function, it is coupled to the pulmonary circulation and the left ventricle. In the face of acute changes in pressure, volume overload and ischemia, it dilates to adapt to its new load. Its manifestation may be ventricular dysfunction and/or failure that will progress to cardiogenic shock due to right ventricular involvement. Various entities may be the cause of acute dysfunction: right ventricular infarction (alterations in contractility due to ischemia) and high-risk pulmonary thromboembolism (increased afterload). Both share a similar ventricular pathophysiology and high mortality without treatment. Understanding anatomy and physiology, dysfunction and acute ventricular failure are important to define a convenient diagnosis and treatment oriented towards pathophysiology. In this first part, the anatomy and physiology, acute right ventricular dysfunction/failure and cardiogenic shock are taken into consideration, from the perspective of these two entities. In another paper, treatment aimed at cardiogenic shock due to right ventricular involvement will be reviewed.

Desde el conocimiento del infarto del ventrículo derecho, el interés por las características del ventrículo derecho ha sido cada vez mayor. Ahora se sabe que la función ventricular derecha es un predictor de mortalidad en diferentes contextos. El ventrículo derecho es una cavidad de baja presión, alta compliancia y alto volumen. Para llevar a cabo su función normal se encuentra acoplado a la circulación pulmonar y al ventrículo izquierdo. Ante alteraciones agudas de sobrecarga de presión, volumen e isquemia, se dilata para adaptarse a su nueva carga. Su manifestación puede ser disfunción o falla ventricular que progresará a choque cardiogénico por involucro del ventrículo derecho. Diversas entidades pueden ser la causa de la disfunción aguda: el infarto del ventrículo derecho (alteraciones de la contractilidad por isquemia) y la tromboembolia pulmonar de alto riesgo (aumento de la poscarga). Ambas comparten una fisiopatología ventricular similar y alta mortalidad sin tratamiento. Entender la anatomía fisiológica, la disfunción y la falla ventricular aguda es importante para definir un diagnóstico oportuno y un tratamiento orientado a la fisiopatología. En esta primera parte se toma en consideración la anatomía fisiológica y la disfunción/falla aguda ventricular derecha y su desenlace en el choque cardiogénico, desde la perspectiva de estas dos entidades. En otro trabajo se revisará el tratamiento orientado al choque cardiogénico por involucro ventricular derecho.

Asunto(s)

RESUMEN

Resumen Introducción: La confiabilidad de la presión sistólica arterial pulmonar por ecocardiografía transtorácica se encuentra limitada por su variabilidad para definir la hipertensión pulmonar. Objetivo: Conocer la variabilidad en la presión sistólica arterial pulmonar estimada por ecocardiografía en la hipertensión pulmonar. Métodos: En el periodo 2016-2020 se captaron sujetos con hipertensión pulmonar que tuvieron estimada la presión sistólica de la arteria pulmonar por ecocardiografía transtorácica y por cateterismo cardiaco derecho. Se obtuvieron sus variables demográficas. Los datos se analizaron con el estadístico descriptivo de Bland-Altman y el coeficiente de correlación intraclase (intervalo de confianza al 95%). Resultados: Se estudiaron 152 sujetos, edad 60 ± 12 años. Índice de masa corporal 27.64 ± 4.69 kg/m2. La presión sistólica de la arteria pulmonar por ecocardiografía transtorácica 58.99 ± 18.62 vs. cateterismo cardiaco 55.43 ± 16.79. Diferencia media (sesgo) -3.6 (29.1, -36.2) y coeficiente de correlación intraclase 0.717 (0.610, 0.794). Conclusiones: La variabilidad es amplia y el acuerdo es sustancial con la presión sistólica de la arteria pulmonar. Se aconseja estimarla solo como tamizaje de la hipertensión pulmonar.

Abstract Introduction: The reliability of pulmonary arterial systolic pressure by transthoracic echocardiography is limited by its variability to define pulmonary hypertension. Objective: To know the variability of pulmonary arterial systolic pressure estimated by echocardiography in pulmonary hypertension. Their demographic variables were obtained. Methods: From 2016-2020 subjects with pulmonary hypertension were recruited, with pulmonary artery systolic pressure estimated by transthoracic echocardiography and by right heart catheterization. Data were analyzed using the Bland-Altman descriptive statistic and the intraclass correlation coefficient (95% confidence interval). Results: 152 subjects, age 60 ± 12 years, were studied. Body mass index 27.64 ± 4.69 kg/m2. The pulmonary artery systolic pressure estimated by transthoracic echocardiography 58.99 ± 18.62 vs. cardiac catheterization 55.43 ± 16.79 mmHg. Mean difference (bias) -3.6 (29.1, -36.2) and intraclass correlation coefficient 0.717 (0.610, 0.794). Conclusions: Variability is wide, and agreement is substantial for pulmonary artery systolic pressure. It is recommended to estimate only as screening for pulmonary hypertension.

RESUMEN

Resumen Introducción: La obesidad mórbida se asocia a alteraciones de la capacidad de caminar, sin embargo se desconoce cómo es el comportamiento de la prueba de caminata de 6 minutos en sujetos con incrementos del índice de masa corporal (IMC). Objetivo: Describir el comportamiento de la prueba de caminata de 6 minutos en sujetos con IMC normal hasta la obesidad mórbida. Métodos: Mediante un diseño transversal analítico se estudiaron sujetos de ambos sexos de 18 a 60 años con IMC: normal (18.5-24.9 kg/m2), sobrepeso (25-29.9 kg/m2), obesidad (30-39.9 kg/m2), obesidad mórbida (> 40 kg/m2). Se les realizó prueba de caminata de 6 minutos, se acotaron variables demográficas y antecedentes personales patológicos. Se analizaron las categorías de IMC con ANOVA de una vía y ajuste de Bonferroni y los sexos con prueba t, ambos para grupos independientes y correlaciones de Pearson para las diversas variables. Una p < 0.05 fue considerada estadísticamente significativa. Resultados: Se estudiaron 480 sujetos de ambos sexos en cuatro grupos. Edad: hombres 43 ± 11 y mujeres 45 ± 10 años. Porcentaje diabetes mellitus (6.7%), hipertensión arterial (18.3%). Metros caminados hombres vs. mujeres por IMC (normal: 483 ± 56 vs. 449 ± 61; sobrepeso: 471 ± 55 vs. 441 ± 44; obesidad: 455 ± 70 vs. 421 ± 47; obesidad mórbida: 443 ± 49 vs. 403 ± 54; p < 0.05). Correlación IMC-metros caminados r: -0.446 (p < 0.0001). Conclusiones: Los metros caminados en la prueba de caminata de 6 minutos disminuyeron conforme incrementó el IMC. El sexo masculino caminó más metros en todas las categorías.

Abstract Introduction: Morbid obesity is associated with alterations in the ability to walk, however, the behavior of the 6-minute walk test in subjects with increases in body mass index is unknown. Objective: To describe the behavior of the 6-minute walk test in subjects with normal body mass index to morbid obesity. Methods: Through an analytical cross-sectional design, subjects of both genders from 18 to 60 years old with body mass index were studied: Normal (BMI: 18.5-24.9); overweight (BMI: 25-29.9); obesity (BMI: 30-39.9); morbid obesity (BMI: > 40) kg/m2. A 6-minute walk test was performed, demographic variables and pathological personal history were delimited. BMI categories were analyzed with one-way ANOVA and Bonferroni adjustment, and gender with t-test, both for independent groups, and Pearson's correlations for the various variables. Results: 480 subjects of both genders were studied in four groups. Age: men 43 ± 11 and women 45 ± 10 years old. Percentage diabetes mellitus (6.7%), arterial hypertension (18.3%). Meters walked men vs. women by body mass index (normal: 483 ± 56 vs. 449 ± 61; overweight: 471 ± 55 vs. 441 ± 44; obesity: 455 ± 70 vs. 421 ± 47; morbid obesity: 443 ± 49 vs. 403 ± 54, p < 0.05). Correlation body mass index-meters walked: r: -0.446 (p < 0.0001). Conclusions: Meters walked in the 6-minute walk test decreased as body mass index increased. The male gender walked more meters in all categories.

RESUMEN

INTRODUCTION: The reliability of pulmonary arterial systolic pressure by transthoracic echocardiography is limited by its variability to define pulmonary hypertension. OBJECTIVE: To know the variability of pulmonary arterial systolic pressure estimated by echocardiography in pulmonary hypertension. Their demographic variables were obtained. METHODS: From 2016-2020 subjects with pulmonary hypertension were recruited, with pulmonary artery systolic pressure estimated by transthoracic echocardiography and by right heart catheterization. Data were analyzed using the Bland-Altman descriptive statistic and the intraclass correlation coefficient (95% confidence interval). RESULTS: 152 subjects, age 60 ± 12 years, were studied. Body mass index 27.64 ± 4.69 kg/m2. The pulmonary artery systolic pressure estimated by transthoracic echocardiography 58.99 ± 18.62 vs. cardiac catheterization 55.43 ± 16.79 mmHg. Mean difference (bias) -3.6 (29.1, -36.2) and intraclass correlation coefficient 0.717 (0.610, 0.794). CONCLUSIONS: Variability is wide, and agreement is substantial for pulmonary artery systolic pressure. It is recommended to estimate only as screening for pulmonary hypertension.

INTRODUCCIÓN: La confiabilidad de la presión sistólica arterial pulmonar por ecocardiografía transtorácica se encuentra limitada por su variabilidad para definir la hipertensión pulmonar. OBJETIVO: Conocer la variabilidad en la presión sistólica arterial pulmonar estimada por ecocardiografía en la hipertensión pulmonar. MÉTODOS: En el periodo 2016-2020 se captaron sujetos con hipertensión pulmonar que tuvieron estimada la presión sistólica de la arteria pulmonar por ecocardiografía transtorácica y por cateterismo cardiaco derecho. Se obtuvieron sus variables demográficas. Los datos se analizaron con el estadístico descriptivo de Bland-Altman y el coeficiente de correlación intraclase (intervalo de confianza al 95%). RESULTADOS: Se estudiaron 152 sujetos, edad 60 ± 12 años. Índice de masa corporal 27.64 ± 4.69 kg/m2. La presión sistólica de la arteria pulmonar por ecocardiografía transtorácica 58.99 ± 18.62 vs. cateterismo cardiaco 55.43 ± 16.79. Diferencia media (sesgo) ­3.6 (29.1, ­36.2) y coeficiente de correlación intraclase 0.717 (0.610, 0.794). CONCLUSIONES: La variabilidad es amplia y el acuerdo es sustancial con la presión sistólica de la arteria pulmonar. Se aconseja estimarla solo como tamizaje de la hipertensión pulmonar.

Asunto(s)

RESUMEN

Background: The 6-minute walk test is widely used and evaluates the functional capacity to perform sub-maximal exercise, its behavior in healthy young native hight-altitude resident is unknown. Objective: To describe the behavior of the 6-minute walk test in healthy young native hight-altitude resident. Material and methods: Analytical cross-sectional design. Consecutive subjects born and residents of the cities of La Paz and El Alto (Bolivia), both genders, without cardiopulmonary disease or physical limitation were studied. Their altitude, hematological, demographic and simple spirometry variables were informed. The differences were calculated with the t-test for independent or dependent groups according to the type of comparison. A p < 0.05 was considered significant. Results: 110 subjects were studied, at an altitude of 3673 ± 250 meters above sea level, age 24 ± 5 years old, 67 (60.90%) were women. The hemoglobin was 15.20 ± 2.46 g/dL. Prior to the test in 37 (33.63%) subjects the partial oxygen saturation was < 92% (90.92 ± 0.92%), its correlation whit meters walked, r = - 0.244, p < 0.010. Total meters walked: 581 ± 35 (627.3 ± 52.88 sea level); with the reference equations from Enright PL: 542 ± 75 and Osses AR: 459 ± 104, both obtained at < 1000 meters above sea level. Vital signs were whitin normal limits. Conclusion: Sub-maximal exercise capacity estimated with the six-minute walk test at high altitude is lower than that reported at sea level.Reference equations underestimated the meters walked at high altitude.

Introducción: la prueba de caminata de 6 minutos es de amplio uso y evalúa la capacidad funcional para realizar ejercicio submáximo, se desconoce su comportamiento en residentes jovenes sanos nativos de gran altitud. Objetivo: describir el comportamiento de la prueba de caminata de 6 minutos en residentes jovenes sanos nativos de gran altitud. Material y métodos: estudio de diseño transversal análitico. Se estudiaron sujetos consecutivos nacidos y residentes de las ciudades de La Paz y El Alto (Bolivia), de ambos géneros, sin enfermedad cardiopulmonar o limitación fisica. Se acotaron variables de altitud, hematológicas, demográficas y espirometria simple. Las diferencias fueron calculadas con la prueba t para grupos independientes o dependientes según la comparación. Una p < 0.05 fue considerada significativa. Resultados: se estudiaron 110 sujetos, altitud de 3673 ± 250 metros sobre el nivel del mar, edad 24 ± 5 años, 67 (60.90%) fueron mujeres. La hemoglobina 15.20 ± 2.46 g/dL, previo a la prueba, en 37 (33.63%) sujetos, la saturación parcial de oxigeno estuvo < 92% (90.92 ± 0.92%), su correlación con metros caminados r = - 0.244, p < 0.010. Metros caminados totales: 581 ± 35 (627.3 ± 52.88 nivel del mar); con las fórmulas de referencia de Enright PL: 542 ± 75, y de Osses AR: 459 ± 104, ambas obtenidas a < 1000 msnm. Los signos vitales estuvieron dentro de limites normales. Conclusión: la capacidad de realizar ejercicio submáximo estimada con la prueba de caminata de 6 minutos en la gran altitud es menor que la referida a nivel del mar. Las formulas de referencia infraestimaron los metros caminados en la gran altitud.

Asunto(s)

RESUMEN

We hypothesized that fetal exposure to the oxidative stress induced by the combined challenge of preeclampsia (PE) and high altitude would induce a significant impairment in the development of pulmonary circulation. We conducted a prospective study in La Paz (Bolivia, mean altitude 3625 m) in which newborns from singleton pregnancies with and without PE were compared (PE group n = 69, control n = 70). We conducted an echocardiographic study in these infants at the median age of two days. The percentage of cesarean deliveries and small for gestational age (SGA) infants was significantly higher in the PE group. Heart rate, respiratory rate, and oxygen saturation did not vary significantly between groups. Estimated pulmonary arterial pressure and pulmonary vascular resistance were 30% higher in newborns exposed to PE and high altitude compared with those exposed only to high altitude. We also detected signs of right ventricular hypertrophy in infants subjected to both exposures. In conclusion, this study provides evidence that the combination of PE and pregnancy at high altitude induces subclinical alterations in the pulmonary circulation of the newborn. Follow-up of this cohort may provide us with valuable information on the potential increased susceptibility to developing pulmonary hypertension or other pulmonary and cardiovascular disorders.

RESUMEN

Introduction: Morbid obesity is associated with alterations in the ability to walk, however, the behavior of the 6-minute walk test in subjects with increases in body mass index is unknown. Objective: To describe the behavior of the 6-minute walk test in subjects with normal body mass index to morbid obesity. Methods: Through an analytical cross-sectional design, subjects of both genders from 18 to 60 years old with body mass index were studied: Normal (BMI:18.5-24.9); overweight (BMI:25-29.9); obesity (BMI:30-39.9); morbid obesity (BMI:>40) kg/m2. A 6-minute walk test was performed, demographic variables and pathological personal history were delimited. BMI categories were analyzed with one-way ANOVA and Bonferroni adjustment, and gender with t-test, both for independent groups, and Pearson's correlations for the various variables. Results: 480 subjects of both genders were studied in four groups. Age: men 43 ± 11 and women 45 ± 10 years old. Percentage diabetes mellitus (6.7%), arterial hypertension (18.3%). Meters walked men vs. women by body mass index (normal: 483 ± 56 vs. 449 ± 61; overweight: 471 ± 55 vs. 441 ± 44; obesity: 455 ± 70 vs. 421 ± 47; morbid obesity: 443 ± 49 vs. 403 ± 54, p < 0.05). Correlation body mass index-meters walked: r: -0.446 (p < 0.0001). Conclusions: Meters walked in the 6-minute walk test decreased as body mass index increased. The male gender walked more meters in all categories.

Introducción: La obesidad mórbida se asocia a alteraciones de la capacidad de caminar, sin embargo se desconoce cómo es el comportamiento de la prueba de caminata de 6 minutos en sujetos con incrementos del índice de masa corporal (IMC). Objetivo: Describir el comportamiento de la prueba de caminata de 6 minutos en sujetos con IMC normal hasta la obesidad mórbida. Métodos: Mediante un diseño transversal analítico se estudiaron sujetos de ambos sexos de 18 a 60 años con IMC: normal (18.5-24.9 kg/m2), sobrepeso (25-29.9 kg/m2), obesidad (30-39.9 kg/m2), obesidad mórbida (> 40 kg/m2). Se les realizó prueba de caminata de 6 minutos, se acotaron variables demográficas y antecedentes personales patológicos. Se analizaron las categorías de IMC con ANOVA de una vía y ajuste de Bonferroni y los sexos con prueba t, ambos para grupos independientes y correlaciones de Pearson para las diversas variables. Una p < 0.05 fue considerada estadísticamente significativa. Resultados: Se estudiaron 480 sujetos de ambos sexos en cuatro grupos. Edad: hombres 43 ± 11 y mujeres 45 ± 10 años. Porcentaje diabetes mellitus (6.7%), hipertensión arterial (18.3%). Metros caminados hombres vs. mujeres por IMC (normal: 483 ± 56 vs. 449 ± 61; sobrepeso: 471 ± 55 vs. 441 ± 44; obesidad: 455 ± 70 vs. 421 ± 47; obesidad mórbida: 443 ± 49 vs. 403 ± 54; p < 0.05). Correlación IMC-metros caminados r: ­0.446 (p < 0.0001). Conclusiones: Los metros caminados en la prueba de caminata de 6 minutos disminuyeron conforme incrementó el IMC. El sexo masculino caminó más metros en todas las categorías.

Asunto(s)

RESUMEN

Background: Usually hemoglobin and hematocrit are obtained from peripheral venous blood samples processed in equipment for hematic biometry. These parameters can also be determined from arterial samples processed on blood gas equipment. Its variability when using arterial samples and this equipment is unknown, in addition, if the lack of knowledge of this variability affects clinical decisions. Objective: To know the variability of hemoglobin and hematocrit from arterial blood samples processed in blood gas equipment. Material and methods: Analytic cross design. Consecutive subjects with stable cardiopulmonary disease were blindly studied. The samples were obtained at the same time for analysis in both equipments. Variability was analyzed with Bland-Altman descriptive statistic and its magnitude with the intraclass correlation coefficient. Results: Two hundred of blood samples from 50 patients were studied, 31 (62%) women, age 62 ± 14 years old, body mass index 30.11 ± 5.69 Kg/m2. The main comparison was peripheral venous blood sample processed in laboratory equipment (SYSMEX) vs. arterial sample on blood gas equipment (GEM). The mean difference (bias) and intraclass correlation coefficient for hemoglobin were: 0.12 (-1.45, 1.23) and 0.95 (0.91, 0.97); for the hematocrit -4.4 (-0.4, 8.54), and 0.72 (0.51, 0.84). Conclusions: The mean difference and bias for hemoglobin was close to 0; the hematocrit was higher. Hemoglobin from arterial samples processed in blood gas equipment can be used to make clinical decisions.

Introducción: usualmente, la hemoglobina y el hematocrito se obtienen de sangre venosa periférica procesada en equipo convencional para biometría hemática, también pueden ser determinados de muestras arteriales procesadas en equipos para gases sanguíneos. Se desconoce su variabilidad al utilizar muestras arteriales y equipos para gases sanguíneos, además, si esta variabilidad pudiera afectar las decisiones clínicas. Objetivo: conocer la variabilidad de la hemoglobina y hematocrito de muestras sanguíneas arteriales procesadas en equipo de gases sanguíneos. Material y métodos: diseño transversal analítico. Se estudiaron de forma ciega sujetos consecutivos con enfermedad cardiopulmonar estable. Las muestras sanguíneas se adquirieron al mismo tiempo para su análisis en ambos equipos. La variabilidad se analizó con el estadístico descriptivo de Bland-Altman y su magnitud con el coeficiente de correlación intraclase. Resultados: se analizaron 200 muestras sanguíneas de 50 pacientes, 31 (62%) mujeres, edad grupal 62 ± 14 años, índice de masa corporal 30.11 ± 5.69 Kg/m2. La principal comparación: muestra sanguínea venosa periférica procesada en equipo del laboratorio (SYSMEX) frente a muestra arterial en equipo de gases sanguíneos (GEM). La diferencia media (sesgo) y el coeficiente de correlación intraclase de la hemoglobina fueron: 0.12 (-1.45, 1.23) y 0.95 (0.91, 0.97); hematocrito -4.4 (-0.4, 8.54) y 0.72 (0.51, 0.84). Conclusiones: la diferencia media y sesgo de la hemoglobina fue cercana a 0; la del hematocrito fue mayor. La hemoglobina de muestras arteriales procesadas en equipos de gases sanguíneos son útiles para tomar decisiones clínicas.

Asunto(s)

RESUMEN

Background: The 6-minute walk test assesses the ability to perform exercise and it is widely used, of low cost, and of diverse variability. Objective: To define the usefulness of a second 6-minute walk test performed 30 minutes from the first. Material and methods. Material and methods: An observational, longitudinal and analytical study was carried out in subjects born and inhabitants from Mexico City, both genders, without cardiopulmonary disease. Their demographic variables were recorded. Differences were calculated with the t test for independent groups and variability with the Bland-Altman statistic; its magnitude, with the intraclass correlation coefficient and 95% confidence intervals (95% CI). A p < 0.05 was considered significant. Results: 200 tests from 100 subjects were studied. Average age was 36 ± 11 years. Body mass index average was 24.71 ± 3.24 kg/m2. 43 subjects were male (43%). The most frequent activity was arts and crafts in 38 (38%). Only 55 subjects (55%) increased by 24 the number of meters walked in the second test. Total of meters walked on walk 1 vs. 2 were: 437.65 ± 48.84 vs. 441.62 ± 11.49. Mean difference (bias) was of -4 (57.9, -65.9) and intraclass correlation coefficient of 0.800 (95% CI, 0.717-0.861). Conclusions: The 6-minute walk test is reproducible with wide variability. These results suggest to do only one 6-minute walk test.

Introducción: la prueba de caminata de seis minutos evalúa la capacidad para hacer ejercicio y es de amplio uso, bajo costo y variabilidad diversa. Objetivo: definir la utilidad de una segunda prueba de caminata de seis minutos realizada a 30 minutos de la primera. Material y métodos: se llevó a cabo un estudio observacional, longitudinal y analítico de sujetos nacidos y habitantes de la Ciudad de México, de ambos géneros, sin enfermedad cardiopulmonar. Se registraron sus variables demográficas. Las diferencias se calcularon con la prueba t para grupos independientes y la variabilidad con el estadístico de Bland-Altman; su magnitud, con el coeficiente de correlación intraclase e intervalos de confianza del 95% (IC 95%). Una p < 0.05 se consideró significativa. Resultados: se estudiaron 200 pruebas de 100 sujetos. La edad promedio fue de 36 ± 11 años. La media del índice de masa corporal fue 24.71 ± 3.24 kg/m2. Fueron 43 hombres (43%). La actividad más frecuente fueron las artes y los oficios en 38 (38%). Solo en 55 (55%) incrementaron en 24 los metros caminados en la segunda prueba. Los metros caminados totales de la caminata 1 frente a la 2 fueron 437.65 ± 48.84 frente a 441.62 ± 11.49. La diferencia media (sesgo) fue de −4 (57.9, −65.9) y el coeficiente de correlación intraclase de 0.800 (IC 95% 0.717-0.861). Conclusiones: la prueba de caminata de seis minutos es reproducible con variabilidad amplia. Estos resultados sugieren realizar solo una prueba de caminata de seis minutos.

Asunto(s)

RESUMEN

Introducción: la prueba de caminata de seis minutos evalúa la capacidad para hacer ejercicio y es de amplio uso, bajo costo y variabilidad diversa. Objetivo: definir la utilidad de una segunda prueba de caminata de seis minutos realizada a 30 minutos de la primera. Material y métodos: se llevó a cabo un estudio observacional, longitudinal y analítico de sujetos nacidos y habitantes de la Ciudad de México, de ambos géneros, sin enfermedad cardiopulmonar. Se registraron sus variables demográficas. Las diferencias se calcularon con la prueba t para grupos independientes y la variabilidad con el estadístico de BlandAltman; su magnitud, con el coeficiente de correlación intraclase e intervalos de confianza del 95% (IC 95%). Una p < 0.05 se consideró significativa. Resultados: se estudiaron 200 pruebas de 100 sujetos. La edad promedio fue de 36 ± 11 años. La media del índice de masa corporal fue 24.71 ± 3.24 kg/m2. Fueron 43 hombres (43%). La actividad más frecuente fueron las artes y los oficios en 38 (38%). Solo en 55 (55%) incrementaron en 24 los metros caminados en la segunda prueba. Los metros caminados totales de la caminata 1 frente a la 2 fueron 437.65 ± 48.84 frente a 441.62 ± 11.49. La diferencia media (sesgo) fue de −4 (57.9, −65.9) y el coeficiente de correlación intraclase de 0.800 (IC 95% 0.717-0.861). Conclusiones: la prueba de caminata de seis minutos es reproducible con variabilidad amplia. Estos resultados sugieren realizar solo una prueba de caminata de seis minutos

Background: The 6-minute walk test assesses the ability to perform exercise and it is widely used, of low cost, and of diverse variability. Objective: To define the usefulness of a second 6-minute walk test performed 30 minutes from the first. Material and methods: An observational, longitudinal and analytical study was carried out in subjects born and inhabitants from Mexico City, both genders, without cardiopulmonary disease. Their demographic variables were recorded. Differences were calculated with the t test for independent groups and variability with the Bland-Altman statistic; its magnitude, with the intraclass correlation coefficient and 95% confidence intervals (95% CI). A p < 0.05 was considered significant. Results: 200 tests from 100 subjects were studied. Average age was 36 ± 11 years. Body mass index average was 24.71 ± 3.24 kg/m2. 43 subjects were male (43%). The most frequent activity was arts and crafts in 38 (38%). Only 55 subjects (55%) increased by 24 the number of meters walked in the second test. Total of meters walked on walk 1 vs. 2 were: 437.65 ± 48.84 vs. 441.62 ± 11.49. Mean difference (bias) was of −4 (57.9, −65.9) and intraclass correlation coefficient of 0.800 (95% CI, 0.717-0.861). Conclusions: The 6-minute walk test is reproducible with wide variability. These results suggest to do only one 6-minute walk test

Asunto(s)

RESUMEN

Background: At high altitude the gas exchange is impaired, in the moderate altitude of Mexico City they are not yet defined. Objective: To characterize the gas exchange in the moderate altitude of Mexico City. Material and methods: Through an analytical cross-sectional study, subjects born and inhabitants of Mexico City, both genders, aged 20 to 59 years without cardiopulmonary disease, were studied. Their demographic variables, simple spirometry and arterial blood gas were recorded. Differences in variables were calculated with one-way ANOVA for independent groups and Bonferroni adjustment. p < 0.05 was accepted as significant. Results: 335 subjects were studied, 168 (50.15%) men. Group age 45 ± 11 years old, body mass index 22.97 ± 1.54 Kg/m2. Forced expiratory volume ratio in the first second / Forced vital capacity (FEV1/FVC) 91.58 ± 12.86%. The arterial oxygen pressure was: 66 ± 5.02 mmHg, carbon dioxide: 32.07 ± 2.66 mmHg, arterial oxygen saturation: 93.0 3 ± 1.80%, and hemoglobin: 14.07 ± 1.52 gr/dL. Conclusions: The arterial oxygen pressure and carbon dioxide are lowered at the Mexico City altitude.

Introducción: en las grandes altitudes, el intercambio gaseoso suele estar deteriorado; en la altitud moderada de la Ciudad de México esto no está aún plenamente definido. Objetivo: caracterizar el intercambio gaseoso en la altitud moderada de la Ciudad de México. Material y métodos: mediante un estudio transversal analítico se estudiaron sujetos nacidos y habitantes de la Ciudad de México, de ambos géneros, con edades de 20 a 59 años sin enfermedad cardiopulmonar. Se registraron sus variables demográficas, espirometría simple y de gasometría arterial. Las diferencias en las variables se calcularon con ANOVA de una vía para grupos independientes y ajuste de Bonferroni. Una p < 0.05 se aceptó como significativa. Resultados: se estudiaron 335 sujetos, de los cuales 168 (50.15%) fueron hombres, la edad grupal fue de 45 ± 11 años, con índice de masa corporal 22.97 ± 1.54 Kg/m2. La relación volumen espiratorio forzado en el primer segundo/ Capacidad vital forzada (VEF1/CVF) de 91.58 ± 12.86%. La presión arterial de oxígeno fue de 66 ± 5.02 mmHg, el bióxido de carbono: 32.07 ± 2.66 mmHg, la saturación arterial de oxígeno: 93.03 ± 1.80% y la hemoglobina: 14.07 ± 1.52 gr/dL. Conclusiones: la presión arterial de oxígeno y del bióxido de carbono están disminuidos a la altura de la Ciudad de México.

Asunto(s)

RESUMEN

Introducción: en las grandes altitudes, el intercambio gaseoso suele estar deteriorado; en la altitud moderada de la Ciudad de México esto no está aún plenamente definido. Objetivo: caracterizar el intercambio gaseoso en la altitud moderada de la Ciudad de México. Material y métodos: mediante un estudio transversal analítico se estudiaron sujetos nacidos y habitantes de la Ciudad de México, de ambos géneros, con edades de 20 a 59 años sin enfermedad cardiopulmonar. Se registraron sus variables demográficas, espirometría simple y de gasometría arterial. Las diferencias en las variables se calcularon con ANOVA de una vía para grupos independientes y ajuste de Bonferroni. Una p < 0.05 se aceptó como significativa. Resultados: se estudiaron 335 sujetos, de los cuales 168 (50.15%) fueron hombres, la edad grupal fue de 45 ± 11 años, con índice de masa corporal 22.97 ± 1.54 Kg/m2. La relación volumen espiratorio forzado en el primer segundo/Capacidad vital forzada (VEF1/CVF) de 91.58 ± 12.86%. La presión arterial de oxígeno fue de 66 ± 5.02 mmHg, el bióxido de carbono: 32.07 ± 2.66 mmHg, la saturación arterial de oxígeno: 93.03 ± 1.80% y la hemoglobina: 14.07 ± 1.52 gr/dL. Conclusiones: la presión arterial de oxígeno y del bióxido de carbono están disminuidos a la altura de la Ciudad de México.

Background: At high altitude the gas exchange is impaired, in the moderate altitude of Mexico City they are not yet defined. Objective: To characterize the gas exchange in the moderate altitude of Mexico City. Material and methods: Through an analytical cross-sectional study, subjects born and inhabitants of Mexico City, both genders, aged 20 to 59 years without cardiopulmonary disease, were studied. Their demographic variables, simple spirometry and arterial blood gas were recorded. Differences in variables were calculated with one-way ANOVA for independent groups and Bonferroni adjustment. p < 0.05 was accepted as significant. Results: 335 subjects were studied, 168 (50.15%) men. Group age 45 ± 11 years old, body mass index 22.97 ± 1.54 Kg/m2. Forced expiratory volume ratio in the first second / Forced vital capacity (FEV1/FVC) 91.58 ± 12.86%. The arterial oxygen pressure was: 66 ± 5.02 mmHg, carbon dioxide: 32.07 ± 2.66 mmHg, arterial oxygen saturation: 93.0 3 ± 1.80%, and hemoglobin: 14.07 ± 1.52 gr/dL. Conclusions: The arterial oxygen pressure and carbon dioxide are lowered at the Mexico City altitude.

Asunto(s)

RESUMEN

BACKGROUND: Inflammation may be an important factor contributing to the progression of Eisenmenger syndrome (ES). The purpose of the current study was to: characterize the inflammatory profile in ES patients and compare measures to reference values for congenital heart disease and pulmonary arterial hypertension (CHD-PAH); and investigate whether inflammatory markers are associated with other clinical markers in ES. METHODS: Twenty-seven ES patients were prospectively selected and screened for systemic inflammatory markers, including interleukin (IL)-1ß, tumor necrosis factor-alpha (TNF-α) and IL-10. Clinical data and echocardiographic parameters were obtained, with concomitant analysis of ventricular function. Functional capacity was assessed using the 6-min walk test (6MWT). Renal function and blood homeostasis were evaluated by the level of blood urea nitrogen (BUN), creatinine, and plasma electrolytes. RESULTS: Patients with ES expressed higher IL-10, IL-1ß and TNF-α compared to reference values of patients with CHD-PAH. IL-10 was negatively associated with BUN (r = -0.39,p = 0.07), creatinine (r = -0.35, p = 0.002), sodium (r = -0.45, p = 0.03), and potassium (r = -0.68, p = 0.003). IL-10 was positively associated with bicarbonate (r = 0.45, p = 0.02) and trended toward a positive association with right ventricular fractional area change (RVFAC) (r = 0.35, p = 0.059). IL-1ß was negatively associated with potassium (r = -0.5, p = 0.01). TNF-α demonstrated positive association with creatinine (r = 0.4,p = 0.006), BUN (r = 0.63,p = 0.003), sodium (r = 0.44, p = 0.04), potassium (r = 0.41, p = 0.04), and was negatively associated with RVFAC (r = -0.38,p = 0.03) and 6MWT distance (r = -0.54, p = 0.004). CONCLUSION: ES patients exhibit a more severe inflammatory profile compared to reference values for CHD-PAH. Furthermore, inflammatory markers are related to renal dysfunction, right ventricular impairment and poorer functional capacity.

Asunto(s)

RESUMEN

Introducción: Las alteraciones del intercambio gaseoso se han reconocido en la obesidad mórbida; sin embargo, no se conoce su comportamiento conforme se incrementa el índice de masa corporal. Objetivo: Conocer el comportamiento del intercambio gaseoso a la altura de la Ciudad de México en el desarrollo de obesidad mórbida. Métodos: Mediante un diseño transversal analítico se estudió a sujetos pareados por género y edad de cuatro grupos diferentes de índice de masa corporal (kg/m2): normal (18.5-24.9), sobrepeso (25-29.9), obesidad (30-39.9) y obesidad mórbida (≥ 40). Se obtuvieron sus antecedentes patológicos y demográficos, variables de gasometría arterial y espirometría simple. Las variables se determinaron de acuerdo con las características de la muestra; las diferencias entre grupos se realizaron mediante Anova de una vía con ajuste de Bonferroni, así como la correlación de Pearson para las variables relacionadas. Una p < 0.05 se consideró con significación estadística. Resultados: Se estudió a 560 pacientes en cuatro grupos. La edad promedio fue de 49 ± 11 años. La mayor frecuencia de diabetes mellitus (34.29%), hipertensión arterial (50%) e hiperlipidemia (36.43%) se registró en el grupo de obesidad, y la de roncador (73.57%) en la obesidad mórbida. Se identificaron diferencias desde el grupo normal respecto de la obesidad mórbida: PaCO2 31.37 ± 2.08 vs. 38.14 ± 5.10 mmHg; PaO2 68.28 ± 6.06 vs. 59.86 ± 9.28 mmHg y SaO2 93.51 ± 1.93 vs. 89.71 ± 5.37%, todas con p = 0.0001. Correlación IMC-PaCO2: 0.497, e IMC-PaO2: -0.365, p = 0.0001, respectivamente. Conclusiones: A la altitud de la Ciudad de México y con índice de masa corporal > 30 kg/m2, las variables relacionadas con el intercambio gaseoso y espirometría simple comienzan a deteriorarse; son evidentes con IMC > 40 kg/m2. Introduction: Alterations of gas exchange have been recognized in morbid obesity, however, it is not known how their behavior would be as the body mass index increases. Objective: To know the behavior of gas exchange at the level of Mexico City in the development of morbid obesity. Methods: Through analytical design, subjects matched by gender and age were studied from four different groups of body mass index (kg/m2), normal (18.5-24.9), overweight (25-29.9), obesity (30-39.9) and morbid obesity (≥ 40). Their pathological and demographic antecedents, arterial blood gas and simple spirometry variables were obtained. The variables were shown according to their sample characteristic. The differences between groups were made using one way Anova with Bonferroni adjustment, as well as Pearson's correlation for the related variables. Statistical significance was considered with p < 0.05. Results: 560 subjects were studied in 4 groups. The average age 49 ± 11 years old. The highest frequency of diabetes mellitus (34.29%), arterial hypertension (50%) and hiperlipidemia (36.43%) was in the obesity group, and being snoring (73.57%) in morbid obesity. There were differences from the normal group versus. morbid obesity: PaCO2 31.37 ± 2.08 versus. 38.14 ± 5.10 mmHg; PaO2 68.28 ± 6.06 versus. 59.86 ± 9.28 mmHg and SaO2 93.51 ± 1.93 versus. 89.71 ± 5.37%, all with p = 0.0001. The IMC-PaCO2 correlation: 0.497, and IMC-PaO2: −0.365, p = 0.0001 respectively. Conclusions: At the altitude of Mexico City and body mass index > 30 kg/m2 the variables related to gas exchange and simple spirometry begin to deteriorate; are evident with BMI > 40 kg/m2.

Asunto(s)

RESUMEN

Chronic exposure to altitude has been associated with hypobaric hypoxia in its inhabitants. Two entities have been associated with it, high altitude pulmonary hypertension and chronic mountain sickness. Its physiological and pulmonary circulation characteristics are described, as well as its clinical profile and diagnosis.

La exposición crónica a la altitud se ha asociado a hipoxia hipobárica en quienes la experimentan. Dos entidades se han asociado a la hipoxia hipobárica: la hipertensión pulmonar de la alta altitud y el mal de montaña crónico. Se describen sus características fisiológicas y de la circulación pulmonar, así como su perfil clínico y el diagnóstico.

Asunto(s)

RESUMEN

Resumen Introducción: Las alteraciones del intercambio gaseoso se han reconocido en la obesidad mórbida; sin embargo, no se conoce su comportamiento conforme se incrementa el índice de masa corporal. Objetivo: Conocer el comportamiento del intercambio gaseoso a la altura de la Ciudad de México en el desarrollo de obesidad mórbida. Métodos: Mediante un diseño transversal analítico se estudió a sujetos pareados por género y edad de cuatro grupos diferentes de índice de masa corporal (kg/m2): normal (18.5-24.9), sobrepeso (25-29.9), obesidad (30-39.9) y obesidad mórbida (≥ 40). Se obtuvieron sus antecedentes patológicos y demográficos, variables de gasometría arterial y espirometría simple. Las variables se determinaron de acuerdo con las características de la muestra; las diferencias entre grupos se realizaron mediante Anova de una vía con ajuste de Bonferroni, así como la correlación de Pearson para las variables relacionadas. Una p < 0.05 se consideró con significación estadística. Resultados: Se estudió a 560 pacientes en cuatro grupos. La edad promedio fue de 49 ± 11 años. La mayor frecuencia de diabetes mellitus (34.29%), hipertensión arterial (50%) e hiperlipidemia (36.43%) se registró en el grupo de obesidad, y la de roncador (73.57%) en la obesidad mórbida. Se identificaron diferencias desde el grupo normal respecto de la obesidad mórbida: PaCO2 31.37 ± 2.08 vs. 38.14 ± 5.10 mmHg; PaO2 68.28 ± 6.06 vs. 59.86 ± 9.28 mmHg y SaO2 93.51 ± 1.93 vs. 89.71 ± 5.37%, todas con p = 0.0001. Correlación IMC-PaCO2: 0.497, e IMC-PaO2: -0.365, p = 0.0001, respectivamente. Conclusiones: A la altitud de la Ciudad de México y con índice de masa corporal > 30 kg/m2, las variables relacionadas con el intercambio gaseoso y espirometría simple comienzan a deteriorarse; son evidentes con IMC > 40 kg/m2.

Abstract Introduction: Alterations of gas exchange have been recognized in morbid obesity, however, it is not known how their behavior would be as the body mass index increases. Objective: To know the behavior of gas exchange at the level of Mexico City in the development of morbid obesity. Methods: Through analytical design, subjects matched by gender and age were studied from four different groups of body mass index (kg/m2), normal (18.5-24.9), overweight (25-29.9), obesity (30-39.9) and morbid obesity (≥ 40). Their pathological and demographic antecedents, arterial blood gas and simple spirometry variables were obtained. The variables were shown according to their sample characteristic. The differences between groups were made using one way Anova with Bonferroni adjustment, as well as Pearson’s correlation for the related variables. Statistical significance was considered with p < 0.05. Results: 560 subjects were studied in 4 groups. The average age 49 ± 11 years old. The highest frequency of diabetes mellitus (34.29%), arterial hypertension (50%) and hiperlipidemia (36.43%) was in the obesity group, and being snoring (73.57%) in morbid obesity. There were differences from the normal group versus. morbid obesity: PaCO2 31.37 ± 2.08 versus. 38.14 ± 5.10 mmHg; PaO2 68.28 ± 6.06 versus. 59.86 ± 9.28 mmHg and SaO2 93.51 ± 1.93 versus. 89.71 ± 5.37%, all with p = 0.0001. The IMC-PaCO2 correlation: 0.497, and IMC-PaO2: −0.365, p = 0.0001 respectively. Conclusions: At the altitude of Mexico City and body mass index > 30 kg/m2 the variables related to gas exchange and simple spirometry begin to deteriorate; are evident with BMI > 40 kg/m2.

Asunto(s)

RESUMEN

A departmental model for the comprehensive care of patients with pulmonary hypertension is presented. The current knowledge of pulmonary hypertension, its mortality, prognosis and the stratification of its severity that justify the proposal of the departmental structure and function are summarized.

Se presenta un modelo departamental para la atención integral de pacientes con hipertensión pulmonar. Se resume el conocimiento actual de la hipertensión pulmonar, su mortalidad, pronóstico y la estratificación de su severidad que justifican la propuesta de la estructura y la función departamental.

Asunto(s)

RESUMEN

Resumo Fundamento: A embolia pulmonar aguda (EPA) tem desfecho clínico variável. A angiotomografia computadorizada (angio-CT) é considerada o padrão-ouro para o diagnóstico. Objetivo: Avaliar se o volume vascular pulmonar (VVP) quantificado por software automatizado é um preditor de mortalidade após EPA. Métodos: Estudo de coorte retrospectivo no qual a imagem da angio-CT de 61 pacientes com EPA foi reanalisada. O VVP e o volume pulmonar (VP) foram estimados automaticamente pelo software Yacta. Calculamos o VVP ajustado pela razão: VVP(cm3)/VP(litros). Parâmetros prognósticos clássicos da angio-CT (carga embólica; razão do diâmetro do ventrículo direito/ventrículo esquerdo; razão do diâmetro da artéria pulmonar/aorta; desvio do septo interventricular; infarto pulmonar e refluxo de contraste na veia hepática) foram avaliados. A mortalidade em 1 mês foi o desfecho analisado. Consideramos um valor de p <0,05 como estatisticamente significativo. Resultados: Sete mortes (11%) ocorreram entre os 61 pacientes durante 1 mês de seguimento. O VVP ajustado <23cm3/L foi um preditor independente de mortalidade na análise univariada (odds ratio [OR]: 26; intervalo de confiança de 95% [IC95%]: 3-244; p=0,004) e na análise multivariada (OR ajustado: 19 [IC95%: 1,3-270]; p=0,03). Os parâmetros clássicos da angio-CT não foram associados à mortalidade em 1 mês nesta amostra. O VVP ajustado <23cm3/L apresentou sensibilidade de 86%, especificidade de 82%, valor preditivo negativo de 94% e valor preditivo positivo de 64% para identificação dos pacientes que morreram. Conclusão: VVP ajustado <23cm3/L foi um preditor independente de mortalidade após EPA. Esse parâmetro mostrou melhor desempenho prognóstico do que os outros achados clássicos da angio-CT. (Arq Bras Cardiol. 2020; 115(5):809-818)

Abstract Background: Acute pulmonary embolism (APE) has a variable clinical outcome. Computed tomography pulmonary angiography (CTPA) is the gold standard for this diagnosis. Objective: To evaluate if the pulmonary vascular volume (PVV) quantified by automated software is a mortality predictor after APE. Methods: Retrospective cohort study where the CTPA imaging of 61 patients with APE was reanalyzed. Pulmonary vascular volume (PVV) and pulmonary volume (PV) were automatically estimated using the Yacta software. We calculated the adjusted PVV by the ratio: PVV(cm3)/PV(liters). Classical prognostic CTPA parameters (clot load index, right ventricle/left ventricle diameter ratio, pulmonary artery/aorta diameter ratio, ventricular septal bowing, pulmonary infarction and reflux of contrast into the hepatic vein) were assessed. The outcome assessed was one-month mortality. We considered a p-value <0.05 as statistically significant. Results: Seven deaths (11%) occurred at one month among these 61 patients. PVV<23cm3/L was an independent predictor of one-month mortality in the univariate [odds ratio (OR): 26; 95% confidence interval (CI): 3-244; p=0.004] and multivariate analyses [adjusted OR: 19; 95%CI: 1.3-270; p=0.03]. The classical CTPA parameters were not associated with one-month mortality in this sample. The PVV<23cm3/L showed a sensitivity of 86%, a specificity of 82%, a negative predictive value of 94% and a positive predictive value of 64% to identify the patients who died. Conclusion: PVV<23cm3/L was an independent predictor of one-month mortality after APE. This parameter showed better prognostic performance than other classical CTPA findings. (Arq Bras Cardiol. 2020; 115(5):809-818)

Asunto(s)