RESUMEN
Impaired aerobic function is a potential mechanism of exercise intolerance in patients with combined cardiorespiratory disease. We investigated the pathophysiological and sensory consequences of a low change in oxygen uptake (ΔV'O2 )/change in work rate (ΔWR) relationship during incremental exercise in patients with coexisting chronic obstructive pulmonary disease (COPD) and systolic heart failure (HF).After clinical stabilisation, 51 COPD-HF patients performed an incremental cardiopulmonary exercise test to symptom limitation. Cardiac output was non-invasively measured (impedance cardiography) in a subset of patients (n=18).27 patients presented with ΔV'O2 /ΔWR below the lower limit of normal. Despite similar forced expiratory volume in 1â s and ejection fraction, the low ΔV'O2 /ΔWR group showed higher end-diastolic volume, lower inspiratory capacity and lower transfer factor compared to their counterparts (p<0.05). Peak WR and peak V'O2 were â¼15% and â¼30% lower, respectively, in the former group: those findings were associated with greater symptom burden in daily life and at a given exercise intensity (leg discomfort and dyspnoea). The low ΔV'O2 /ΔWR group presented with other evidences of impaired aerobic function (sluggish V'O2 kinetics, earlier anaerobic threshold) and cardiocirculatory performance (lower oxygen pulse, lower stroke volume and cardiac output) (p<0.05). Despite similar exertional hypoxaemia, they showed worse ventilatory inefficiency and higher operating lung volumes, which led to greater mechanical inspiratory constraints (p<0.05).Impaired aerobic function due to negative cardiopulmonary-muscular interactions is an important determinant of exercise intolerance in patients with COPD-HF. Treatment strategies to improve oxygen delivery to and/or utilisation by the peripheral muscles might prove particularly beneficial to these patients.
Asunto(s)
Tolerancia al Ejercicio , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno , Estudios ProspectivosRESUMEN
BACKGROUND: Exercise oscillatory ventilation (EOV) is associated with poor ventilatory efficiency and higher operating lung volumes in heart failure. These abnormalities may be particularly deleterious to dyspnea and exercise tolerance in mechanically-limited patients, e.g. those with coexistent COPD. METHODS: Ventilatory, gas exchange and sensory responses to incremental exercise were contrasted in 68 heart failure-COPD patients (12 EOV+). EOV was established by standard criteria. RESULTS: Compared to EOV-, EOV+ had lower exercise capacity, worse ventilatory inefficiency and higher peak dyspnea scores (p<0.05). Peak capillary PCO2 (PcCO2) was higher and end-tidal CO2 (PETCO2) was lower in EOV+. Thus, greater (i.e., more positive) P(c-ET)CO2 and dead space/tidal volume values were found in these patients compared to EOV- (p<0.05). Ventilatory inefficiency was related to increased dead space/tidal volume in EOV+ (r=0.74; p<0.01). Owing to higher operating lung volumes, inspiratory reserve volume (IRV) decreased to a greater extent in EOV+. Tidal volume oscillations consistently ceased when a "critical" IRV was reached (~0.3-0.5L); thereafter, PcCO2 stabilized or increased and dyspnea scores rose sharply. Exercise capacity was closely related to IRV decrements and peak dyspnea in EOV+ (r=-0.78 and 0.84, respectively; p<0.01). CONCLUSIONS: Dyspnea and exercise tolerance are negatively influenced by EOV in heart failure patients presenting with COPD as co-morbidity. Pharmacological and non-pharmacological interventions known to decrease EOV might prove particularly valuable to mitigate symptom burden and exercise intolerance in this specific heart failure group.
Asunto(s)
Disnea/etiología , Tolerancia al Ejercicio/fisiología , Ejercicio Físico/fisiología , Insuficiencia Cardíaca , Enfermedad Pulmonar Obstructiva Crónica , Anciano , Prueba de Esfuerzo/métodos , Femenino , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno/fisiología , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Ventilación Pulmonar/fisiología , Pruebas de Función Respiratoria/métodos , Estadística como AsuntoRESUMEN
Ventilatory inefficiency during exercise is a key pathophysiological feature of chronic obstructive pulmonary disease. Currently, it is unknown how this physiological marker relates to clinically relevant outcomes as resting ventilatory impairment progresses across disease stages. Slope and intercept of the linear region of the ventilation-carbon dioxide output relationship and the ratio between these variables, at the lowest point (nadir), were contrasted in 316 patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages 1-4 (forced expiratory volume in 1 s, ranging from 148% pred to 12% pred) and 69 aged- and gender-matched controls, Compared to controls, slope and intercept were higher in GOLD stages 1 and 2, leading to higher nadirs (p<0.05). Despite even larger intercepts in GOLD stages 3 and 4, slopes diminished as disease evolved (from mean±sd 35±6 in GOLD stage 1 to 24±5 in GOLD stage 3, p<0.05). As a result, there were no significant differences in nadirs among patient groups. Higher intercepts, across all stages (p<0.01), and to a lesser extent lower slopes in GOLD stages 2-4 (p<0.05), were related to greater mechanical constraints, worsening pulmonary gas exchange, higher dyspnoea scores, and poorer exercise capacity. Increases in the ventilation intercept best indicate the progression of exercise ventilatory inefficiency across the whole spectrum of chronic obstructive pulmonary disease severity.
Asunto(s)
Ejercicio Físico , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Respiración , Anciano , Dióxido de Carbono , Estudios de Casos y Controles , Progresión de la Enfermedad , Disnea/fisiopatología , Prueba de Esfuerzo , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Persona de Mediana Edad , Intercambio Gaseoso Pulmonar , Pruebas de Función Respiratoria , Descanso , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del TratamientoRESUMEN
The advent of microprocessed "metabolic carts" and rapidly incremental protocols greatly expanded the clinical applications of cardiopulmonary exercise testing (CPET). The response normalcy to CPET is more commonly appreciated at discrete time points, for example, at the estimated lactate threshold and at peak exercise. Analysis of the response profiles of cardiopulmonary responses at submaximal exercise and recovery, however, might show abnormal physiologic functioning which would not be otherwise unraveled. Although this approach has long been advocated as a key element of the investigational strategy, it remains largely neglected in practice. The purpose of this paper, therefore, is to highlight the usefulness of selected submaximal metabolic, ventilatory, and cardiovascular variables in different clinical scenarios and patient populations. Special care is taken to physiologically justify their use to answer pertinent clinical questions and to the technical aspects that should be observed to improve responses' reproducibility and reliability. The most recent evidence in favor of (and against) these variables for diagnosis, impairment evaluation, and prognosis in systemic diseases is also critically discussed.
RESUMEN
FUNDAMENTO: A síndrome coronariana aguda (SCA) sem supradesnivelamento do segmento ST (SCASEST) está associada ao supradesnivelamento do peptídeo natriurético tipo B (BNP) e aos marcadores de necrose miocárdica, embora se desconheça a correlação dessa síndrome ao escore de trombólise no infarto do miocárdio (TIMI) e à função ventricular esquerda. OBJETIVO: Avaliar a correlação entre os níveis do fragmento N-terminal do peptídeo natriurético tipo B (NT-proBNP) e os marcadores de necrose miocárdica (creatinofosfoquinase fração músculo-cérebro CK-MB e troponina I), bem como entre o escore de risco TIMI e a fração de ejeção do ventrículo esquerdo (FEVE) nos pacientes com síndrome coronariana aguda sem supradesnivelamento do segmento ST. MÉTODOS: Oitenta e sete pacientes com síndrome coronariana aguda sem supradesnivelamento do segmento ST foram divididos em dois grupos: 37 (42,5 por cento) com angina instável e 50 (57,5 por cento) com infarto agudo do miocárdio sem supradesnivelamento do segmento ST (IAMSSST). RESULTADOS: A fração de ejeção do ventrículo esquerdo superior a 40 por cento foi encontrada em 86,2 por cento do total da amostra. Os níveis séricos de NT-proBNP foram maiores em pacientes com infarto do miocárdio sem supradesnivelamento do segmento ST, em comparação àqueles com angina instável (p<0,001). O aumento dos níveis de NT-proBNP foi associado ao aumento de troponina I (rs=0,425, p<0,001), pico de CK-MB (rs=0,458, p<0,001) e FEVE (rs=-0,345, p=0,002), não havendo correlação com o escore de risco TIMI (rs=0,082, p=0,44). Na análise multivariada, a fração de ejeção do ventrículo esquerdo e a troponina I correlacionaram-se de forma independente aos níveis de NT-proBNP (p=0,017 e p=0,002, respectivamente). CONCLUSÃO: O aumento dos níveis de NT-proBNP em pacientes com síndrome coronariana aguda sem supradesnivelamento do segmento ST não está relacionado exclusivamente à redução da fração de ejeção do ventrículo esquerdo, mas também pode ser provocado pela presença de isquemia miocárdica e necrose.
BACKGROUND: Non-ST-segment elevation acute coronary syndrome is associated with elevation of brain natriuretic peptide and markers of myocardial necrosis, although its relationship with the TIMI score and left ventricular function are largely unknown. OBJECTIVE: To evaluate the correlation between plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) and markers of myocardial necrosis [creatine phosphokinase muscle-brain fraction (CK-MB) and troponin I], TIMI risk score and left ventricular ejection fraction in patients with non-ST-segment elevation acute coronary syndrome. METHODS: Eighty-seven patients with non-ST-segment elevation acute coronary syndrome were divided into two groups: 37 (42.5 percent) with unstable angina and 50 (57.5 percent) with non-ST-segment elevation myocardial infarction. RESULTS: Left ventricular ejection fraction more than 40 percent was found in 86.2 percent of the total sample. Serum levels of NT-proBNP was higher in patients with non-ST elevation myocardial infarction than in those with unstable angina (p<0.001). Increased levels of NT-proBNP were associated with increases in troponin I (rs=0.425, p<0.001), peak CK-MB (rs=0.458, p<0.001) and low left ventricular ejection fraction (rs=-0.345, p=0.002); no correlation was found with the TIMI risk score (rs=0.082, p=0.44). Multivariate analysis revealed that left ventricular ejection fraction and troponin I levels were independently correlated with NT-proBNP levels (p=0.017 and p=0.002, respectively). CONCLUSION: Increased levels of NT-proBNP in patients with non-ST-segment elevation acute coronary syndrome are not related exclusively to low left ventricular ejection fraction, but can also be caused by the presence of myocardial ischemia and necrosis.
Asunto(s)
Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome Coronario Agudo/sangre , Forma MB de la Creatina-Quinasa/sangre , Miocardio/patología , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Troponina I/sangre , Síndrome Coronario Agudo/fisiopatología , Biomarcadores/sangre , Métodos Epidemiológicos , Necrosis , Medición de Riesgo , Volumen Sistólico/fisiologíaRESUMEN
BACKGROUND: Non-ST-segment elevation acute coronary syndrome is associated with elevation of brain natriuretic peptide and markers of myocardial necrosis, although its relationship with the TIMI score and left ventricular function are largely unknown. OBJECTIVE: To evaluate the correlation between plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) and markers of myocardial necrosis [creatine phosphokinase muscle-brain fraction (CK-MB) and troponin I], TIMI risk score and left ventricular ejection fraction in patients with non-ST-segment elevation acute coronary syndrome. METHODS: Eighty-seven patients with non-ST-segment elevation acute coronary syndrome were divided into two groups: 37 (42.5%) with unstable angina and 50 (57.5%) with non-ST-segment elevation myocardial infarction. RESULTS: Left ventricular ejection fraction more than 40% was found in 86.2% of the total sample. Serum levels of NT-proBNP was higher in patients with non-ST elevation myocardial infarction than in those with unstable angina (p<0.001). Increased levels of NT-proBNP were associated with increases in troponin I (rs=0.425, p<0.001), peak CK-MB (rs=0.458, p<0.001) and low left ventricular ejection fraction (rs=-0.345, p=0.002); no correlation was found with the TIMI risk score (rs=0.082, p=0.44). Multivariate analysis revealed that left ventricular ejection fraction and troponin I levels were independently correlated with NT-proBNP levels (p=0.017 and p=0.002, respectively). CONCLUSION: Increased levels of NT-proBNP in patients with non-ST-segment elevation acute coronary syndrome are not related exclusively to low left ventricular ejection fraction, but can also be caused by the presence of myocardial ischemia and necrosis.
Asunto(s)
Síndrome Coronario Agudo/sangre , Forma MB de la Creatina-Quinasa/sangre , Miocardio/patología , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Troponina I/sangre , Síndrome Coronario Agudo/fisiopatología , Biomarcadores/sangre , Métodos Epidemiológicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Necrosis , Medición de Riesgo , Volumen Sistólico/fisiologíaRESUMEN
AIMS: The effects of exercise training in chronic heart failure are well established, however, they have not been evaluated in Chagas cardiomyopathy (ChC). We sought to determine the effects of exercise training on functional capacity, health-related quality of life (HQoL), and brain natriuretic peptide (BNP) levels in patients with ChC. METHODS AND RESULTS: This randomized, controlled, single-blind trial included 40 patients with ChC (age 49.5 +/- 7.8 years, 57.5% male) who did not practice regular exercise. All patients were assessed, at baseline and at the end of the study, by exercise test (VO(2) and exercise time), six-minute walk test (6MWT), Goldman Specific Activity Scale (SAS), HQoL, and BNP levels. Patients were randomized to inactive control group (ICG = 19) or exercise training group (ETG = 21). Exercise training group patients underwent 12 weeks of exercise training: walking for up to 30 min (intensity 50-70% HR reserve + HR at rest) and warm-up and cooling-down exercising, three times a week. The data were analysed for delta values (Delta= end - baseline). After intervention, compared with the ICG, the ETG had significant increases in functional parameters including, DeltaVO(2) (6.5 vs. 2.8 mL/kg/min, P = 0.001), Delta exercise time (2.9 vs.1.1 min, P < 0.001), Delta6MWT distance (83.5 vs. 2.0 m, P = 0.001) improved DeltaSAS (8 vs. 1 patient, P = 0.008), and HQoL: Delta domains vitality (7.5 vs. 0 points, P = 0.013), Delta emotional aspects (16.7 vs. 0 points, P = 0.012), and Delta mental health (16.1 vs. 0 points, P = 0.031). There was no difference in BNP levels. CONCLUSION: In patients with ChC, exercise training was associated with a major improvement in functional capacity and HQoL without any adverse effects.
Asunto(s)
Cardiomiopatía Chagásica/terapia , Terapia por Ejercicio , Tolerancia al Ejercicio , Adulto , Cardiomiopatía Chagásica/psicología , Prueba de Esfuerzo , Femenino , Indicadores de Salud , Humanos , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico/sangre , Consumo de Oxígeno , Cooperación del Paciente , Calidad de Vida/psicología , Método Simple Ciego , Encuestas y CuestionariosRESUMEN
UNLABELLED: Parameters of diastolic function have been shown to correlate with exercise capacity (EC) in individuals with impaired left ventricular (LV) systolic function. However, the role of LV diastolic function in predicting EC in Chagas cardiomyopathy has not been reported. OBJECTIVES: This study aimed to determine the relationship between LV diastolic parameters assessed by echocardiography and EC in patients with Chagas cardiomyopathy. METHODS: We studied 40 patients (23 men; 49 + or - 8 years), with diagnosis of Chagas disease and dilated cardiomyopathy. Medical therapy was individually adjusted according to standardized guidelines. Methods of acquiring two-dimensional Doppler, tissue Doppler imaging (TDI), and their measurements were described. Exercise testing was performed by a Bruce protocol. Brain natriuretic peptide (BNP) levels were also determined. RESULTS: Most patients (63%) were in NYHA functional class I. Mean peak oxygen consumption estimated (peakVO(2)) was 31.7 + or - 10.2 mL/kg per minute, and mean left ventricular ejection fraction (LVEF) was 36.3 + or - 7.8%. Univariate analysis showed that various echocardiographic parameters of diastolic function were correlated with peakVO(2). There was no correlation between BNP levels or LVEF and EC. Multivariate analysis, after adjustment for age and gender, revealed that E/E' ratio and left atrial volume (LAV), emerged as independent predictors of EC, as demonstrated in the model: peakVO(2)= 60.825 + (0.439 x LAV) - (1.620 x E/E' ratio) - (0.483 x age) - (4.821 x female gender). The R(2) of this model was 0.52. CONCLUSIONS: Functional capacity assessed by peakVO(2) was related to increase LV filling pressures, independently on systolic function in patients with Chagas cardiomyopathy. (Echocardiography 2010;27:519-524).
Asunto(s)
Cardiomiopatía Chagásica/diagnóstico por imagen , Cardiomiopatía Chagásica/fisiopatología , Ecocardiografía/métodos , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/fisiopatología , Diástole , Ensayo de Inmunoadsorción Enzimática , Prueba de Esfuerzo , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico/sangre , Consumo de Oxígeno/fisiología , Estadísticas no Paramétricas , SístoleRESUMEN
UNLABELLED: Acute coronary syndromes in the absence of ST-segment elevation (NSTE-ACS) are a heterogeneous entity in which early risk stratification is essential. Diastolic dysfunction is precocious and associated with poor prognosis. BNP has been recognized as a biochemical marker of ventricular dysfunction and ischemia. OBJECTIVE: To investigate if there is correlation of NT pro-BNP levels with diastolic dysfunction in patients with NSTE-ACS. METHODS: Fifty-two patients with NSTE-ACS admitted to the coronary unit were included. NT-pro brain natriuretic hormone (BNP) levels and a Doppler echocardiogram were obtained in all and systolic and diastolic functions were analyzed. Their Doppler indexes were compared with those of 53 age- and sex-matched controls, without heart failure symptoms and with normal ejection fraction (EF) and normal NT-pro BNP levels. RESULTS: Twenty-four patients (46%) with unstable angina and 28 patients (54%) with acute myocardial infarction (AMI) were included. Mean EF was 55.9 +/- 10.7% and mean NT-pro BNP level was 835 +/- 989 pg/ml. No mitral or pulmonary venous flow parameters of diastolic function correlated with NT-pro BNP levels. E'/A' correlated with NT-pro BNP level in univariate analysis but, in a multivariate analysis, only the EF and the E' showed negative correlation with the peptide level (r =-0.33, P = 0.024 and r =-0.29, P = 0.045, respectively). Thirteen patients presented with stage II diastolic dysfunction but the NT-pro BNP level in these patients did not differ from the level in stage I patients. CONCLUSION: NT-pro BNP levels are elevated in acute coronary syndromes, even in the absence of significant necrosis. Of all echocardiographic parameters investigated, only E' and the EF correlated with the levels of NT-pro BNP in this group of patients.
Asunto(s)
Velocidad del Flujo Sanguíneo/fisiología , Enfermedad Coronaria/sangre , Electrocardiografía , Válvula Mitral/fisiopatología , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Función Ventricular Izquierda/fisiología , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/fisiopatología , Estudios Transversales , Diástole , Ecocardiografía Doppler en Color/métodos , Femenino , Humanos , Inmunoensayo , Masculino , Persona de Mediana Edad , Válvula Mitral/diagnóstico por imagen , Pronóstico , Estudios Prospectivos , Precursores de Proteínas , Índice de Severidad de la Enfermedad , SíndromeRESUMEN
OBJECTIVE: To investigate the correlation between the endothelial function and the carotid intimal-medial thickening (IMT) in a population of patients with coronary artery disease, as well as that between the endothelial function and carotid IMT with the severity of the coronary lesions. METHODS: Forty-three patients aged 60.5+/-9.2 years, (67.4% males) with coronary artery disease at the coronariography were studied. Endothelial function was assessed using the brachial artery reactivity test (BART), which measured the percentage of flow-mediated dilatation (%FMD). The carotid IMT was evaluated through vascular ultrasound. RESULTS: The mean %FDM was 4.7 +/- 3.6 and the mean carotid IMT was 1.08 +/- 0.23 mm. The carotid MIT and %FMD measurements showed a statistically significant correlation, with Spearmans coefficient of 0.315, p= 0.042, demonstrating that lower %FMD values corresponded to an increased carotid IMT (r = -0.315, p = 0.042). There was no correlation between %FMD or IMT and the severity of coronary lesions. CONCLUSIONS: The presence of a correlation between carotid IMT and %FMD demonstrates a concomitance of anatomical and functional vascular alterations in coronary artery disease, regardless of the severity of the atherosclerotic lesions.
Asunto(s)
Arteria Braquial/fisiología , Enfermedad de la Arteria Coronaria/fisiopatología , Endotelio Vascular/fisiología , Aterosclerosis/etiología , Arteria Braquial/diagnóstico por imagen , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/patología , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/patología , Femenino , Humanos , Hiperemia/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Factores de Riesgo , Túnica Media/diagnóstico por imagen , Túnica Media/patología , Túnica Media/fisiopatologíaRESUMEN
OBJETIVO: Investigar uma correlação entre o teste de reatividade da artéria braquial (BART) e o espessamento médio-intimal (EMI) da carótida em uma população de pacientes com doença arterial coronariana, assim como avaliar uma correlação do BART e do EMI da carótida com a gravidade da doença arterial coronariana demonstrada através da coronariografia. MÉTODOS: Quarenta e dois pacientes (idade: 60,7 ± 9,2 anos, 66,7 por cento do sexo masculino) com doença arterial coronariana por coronariografia foram estudados. A função endotelial foi avaliada de modo não-invasivo através do BART, quando foi medido o porcentual de dilatação mediada pelo fluxo ( por centoDMF). O EMI de carótida foi avaliado por meio de ultra-som vascular. RESULTADOS: A média de por centoDMF foi de 4,7 ± 3,6 e a média de EMI de carótida foi de 1,08 ± 0,23 mm. As medidas do EMI de carótida e do por centoDMF apresentaram correlação estatisticamente significativa, com coeficiente de Spearman de -0,315, valor p = 0,042, demonstrando que valores menores de por centoDMF se correlacionaram a um maior EMI de carótida. Não houve correlação entre por centoDMF, EMI e a gravidade das lesões; CONCLUSÃO: A presença de uma correlação entre o por centoDMF e o EMI da carótida demonstra a concomitância de alterações vasculares funcionais e anatômicas na doença arterial coronariana, independentemente da gravidade das lesões ateroscleróticas.