Effect of smoking habit on cardiopulmonary function in patients with myocardial infarction -A study based on cardiopulmonary exercise testing- / 体力科学

The purpose of this study was to examine the relationship between smoking and cardiopulmonary function, and the effect of smoking habit on exercise tolerance after discharge from the hospital, focusing on CPX test data of patients hospitalized for acute myocardial infarction, and on CPX test data at 6 months after discharge. A total of 123 male patients hospitalized for acute myocardial infarction between April 2014 and December 2020 were included. Laboratory and CPX data were compared between smokers and non-smokers. CPX data of smokers, ex-smokers and non-smokers were also compared in 24 patients who underwent CPX examination 6 months after discharge. HDL-C was significantly decreased (p < 0.05) and τON was significantly prolonged (p < 0.05) during hospitalization in smokers. τON was significantly shorter only in ex-smokers (p < 0.05) 6 months after discharge compared to during hospitalization. These results suggest that τON, which reflects the oxygen uptake kinetics of peripheral tissues, is shortened by smoking cessation.

Evaluation of myocardial microcirculation abnormalities in patients with hypertrophic cardiomyopathy by myocardial contrast echocardiography combined with exercise stress test / 中华超声影像学杂志

Objective:To detect the abnormal changes of myocardial blood perfusion in patients with hypertrophic cardiomyopathy (HCM) by myocardial contrast echocardiography(MCE) combined with exercise stress test.Methods:Twenty-seven patients with clinically diagnozed of asymmetric HCM in Fuwai Central China Cardiovascular Hospital from May 2020 to April 2021 were selected as the HCM group, and 29 healthy subjects during the same period were selected as the control group. All patients underwent routine echocardiography, resting and exercise stress MCE. The myocardial perfusion parameters of each segment of interventricular septum in the 2 groups were quantitatively analyzed: the peak plateau intensity (A value), ascending slope of the curve(β value) and value of A×β. According to the end-diastolic myocardial thickness, the interventricular septum of the HCM group was divided into hypertrophic and non-hypertrophic segments, and the myocardial contrast parameters of the interventricular septum of the study group were compared with those of the control group. The myocardial blood flow reserve value of the two groups were calculated, and the correlation of myocardial blood flow reserve value with left ventricular mass index (LVMI) and left ventricular remodeling index (LVRI) were analyzed.Results:No matter at rest or under stress, the A value, β value and A×β value of ventricular septal hypertrophic and non-hypertrophic segments in the hypertrophic cardiomyopathy group were lower than those in the control group, and the differences were statistically significant (all P<0.05). Under stress, the A value, β value and A×β value of interventricular septal hypertrophic segments were lower than those in non-hypertrophic segments in the HCM group, and the differences were statistically significant (all P<0.05). The myocardial blood flow reserve in the HCM group was negatively correlated with LVMI and LVRI( r=-0.899, -0.676; all P<0.001). Conclusions:In patients with HCM under resting and exercise stress, microcirculation disorders were found in both hypertrophic and non-hypertrophic segments of the ventricular wall, and the myocardial blood flow reserve was negatively correlated with LVMI and LVRI.

Study on the application of exercise stress echocardiography combined with layer-sepcific strain in patients with essential hypertension / 中华超声影像学杂志

Objective:To evaluate the diagnostic value of exercise stress echocardiography combined with left ventricular two-dimensional speckle tracking layer-specific strain technique in evaluating subclinical myocardial damage and reserve function in patients with hypertension.Methods:A total of 51 healthy subjects(control group) and 55 hypertensive patients (hypertension group) were enrolled in the treadmill exercise stress test in Sichuan Provincial People′s Hospital from October 2018 to January 2020. According to the European Guidelines for the Prevention and Treatment of Hypertension, the inclusion criteria for patients with hypertension were: blood pressure≥140/90 mmHg or who explicitly took antihypertensive drugs, and related cardiovascular diseases were excluded. The conventional parameters of resting and peak exercise, including left ventricular mass index, left ventricular end-diastolic volume index and left ventricular ejection fraction et al, were analyzed by speckle tracking software in two groups. According to the standard images in the resting and peak exercise, the endocardium /mid-myocardium /epicardium of left ventricular (three-, two-, four-chamber and global) longitudinal strain and circumferential strain (papillary muscle level) were compared respectively in two groups. The characteristics of strain differences and the systolic function reserve between the resting and peak exercise were evaluated.Results:There were significant differences in conventional ultrasound parameters between resting and peak exercise period in hypertension group, except E/A and e/a ratio (all P<0.05), and E/e value increased significantly(12.1±0.38) during peak exercise, indicating impaired diastolic reserve function. The longitudinal and circumferential layer-specific strain values from endocardial to epicardial were gradually decreased in both two groups. Compared with the control group, the resting longitudinal and circumferential endocardial strain values in hypertensive group were decreased, and the differences were more obvious at peak status, for instance global longitudinal endocardium strain at rest[control group (24.4±1.5)%, hypertension group (20.4±2.3)%], peak status[control group (30.8±2.8)%, hypertension group (22.8±2.9)%]( P<0.05). There were no significant differences of the partial layer-specific strain values between the peak exercise and resting status in hypertension group, while peak layer-specific strain of the control group were all significantly increased, suggesting that the left ventricular systolic reserve function of hypertension patients was lower than that of the control group. Conclusions:Left ventricular layer-specific strain can effectively evaluate the myocardial function in patients with hypertension, especially the endocardial strain can be used as an indicator parameter, and the peak exercise stress state is more sensitive. The systolic and diastolic reserve function of the left ventricle in patients with hypertension at the peak period are reduced to different degrees. Exercise stress echocardiography combined with left ventricular layer-specific strain technique can be used as a new method for detection of myocardial function impairment in patients with hypertension.

Respuestas cardiovasculares de pacientes con obesidad en la prueba de esfuerzo / Cardiovascular responses of obese patients to exercise stress test

RESUMEN Introducción: La obesidad es una enfermedad multisistémica que constituye un factor de riesgo coronario y se asocia frecuentemente a otros, como la hipertensión arterial, la diabetes y la dislipidemia, todo lo cual aumenta el riesgo de enfermedad cardiovascular. Objetivo: Determinar la respuesta cardiovascular de los pacientes con obesidad durante una prueba de esfuerzo. Método: Estudio observacional, descriptivo y transversal con 67 participantes obesos (45 mujeres y 22 hombres), con promedio de edad de 35±12,6 años. Para el desarrollo de esta investigación se obtuvieron variables antropométricas, signos vitales, escala de Borg, cuestionario para factores de riesgo cardiovascular, y se realizó una prueba de esfuerzo en tapiz rodante con protocolo de Bruce. Resultados: Los principales factores de riesgo cardiovascular encontrados fueron el sedentarismo (100%) y los antecedentes patológicos familiares (76%). Se obtuvo una frecuencia cardíaca máxima promedio de 172,82±18,81 latidos por minuto, que fue superior en las mujeres (173,9±17,5 vs. 168,9±22,1) y al asociarla con los factores de riesgo cardiovascular se encontró que fue mayor en los pacientes con menos de 4 factores de este tipo (179,4±17,7 vs. 167,1±18,6). Conclusiones: Se encontró una disminución de la respuesta cardiovascular en relación con el esfuerzo esperado para la prueba de esfuerzo. A mayor número de factores de riesgo cardiovascular presentes, menor fue la frecuencia cardíaca máxima alcanzada.

ABSTRACT Introduction: Obesity is a multisystemic disease and a coronary risk factor that is frequently associated with others, such as high blood pressure, diabetes and dyslipidemia. These all increase the risk of heart disease. Objective: We aimed to determine the cardiovascular response of obese patients during a stress test. Methods: An observational, descriptive and cross-sectional study was conducted with 67 obese participants (45 women and 22 men) aged 35±12.6 years on average. To develop our research, we analyzed anthropometric variables and vital signs. The Borg scale, a cardiovascular risk factor interview and a Bruce treadmill stress test protocol were also applied. Results: The main cardiovascular risk factors found were sedentary lifestyle (100%) and family history of disease (76%). An average maximum heart rate of 172.82±18.81 beats per minute was obtained, which was higher in women (173.9±17.5 vs. 168.9±22.1). It was found to be higher in patients with less than four cardiovascular risk factors (179.4±17.7 vs. 167.1±18.6) when associated with cardiovascular risk factors. Conclusions: A decrease in cardiovascular response was found in relation to the expected test effort. The greater the number of cardiovascular risk factors, the lower the maximum heart rate achieved.

Quantification of left ventricular performance in different phenotypes of hypertrophic cardiomyopathy / 中华超声影像学杂志

Objective To evaluate the characteristics of left ventricular structure ,function ,myocardial mechanics ,hemodynamics and synchrony in different phenotypes of hypertrophic cardiomyopathy ( HCM ) using state‐of‐the‐art echocardiography . Methods A consecutive series of 85 adult HCM patients w ho were admitted to the Xi Jing HCM center from January 2016 to November 2017 were collected . According to the peak left ventricular outflow tract pressure gradient in exercise stress echocardiography ,the patients were divided into three groups :patients with non‐obstructive HCM ( n ＝28) ,those with labile‐obstructive HCM ( n ＝27) ,and those with obstructive HCM ( n ＝ 30 ) . In addition ,16 normal family members of HCM patients were included as control group . T wo‐dimensional speckle tracking imaging ,tissue Doppler imaging and exercise stress echocardiography were used to evaluate the left ventricular function in resting and exercise states . Results ① As compared with the control group ,left ventricular end‐diastolic diameter decreased and left ventricular ejection fraction increased in all three HCM groups ( all P ＜ 0 .05 ) . Left ventricular maximum wall thickness and left ventricular mass index were the highest in obstructive HCM , followed by labile‐obstructive and non‐obstructive HCM ,and the lowest in the control group ( all P ＜0 .05) . ②A t rest ,the left ventricular global longitudinal ,circumferential and radial strain ( GLS ,GCS and GRS) ,as well as the twist of obstructive HCM were significantly lower than the other three groups ( all P ＜0 .05) . As compared with the control group ,the GLS and twist decreased in the labile‐obstructive and non‐obstructive HCM ( all P ＜0 .05 ) ,but there were no significant changes of GCS and GRS ( all P ＞ 0 .05 ) . T he obstructive HCM had the lowest mitral annular plane systolic excursion ( M APSE ) and s′,and the longest systolic peaking time standard deviation( T s‐SD) and early diastolic peaking time standard deviation ( Te‐SD) ( all P ＜0 .05) . T he left ventricular diastolic function of obstructive HCM ( e′,the E/e′ratio and the left atrial volume index ) was the worst ,labile‐obstruction and non‐obstructive HCM were better ,and the control group was the best ( all P ＜ 0 .001 ) . ③ During exercise ,the GLS ,GCS ,GRS ,twist of the left ventricle and the M APSE were the lowest in the obstructive HCM ,which increased in the labile‐obstructive and non‐obstructive HCM ,and were best in the control group . T he T s‐SD and Te‐SD were the shortest in the control group ,were prolonged in non‐obstructive and labile‐obstruction HCM ,and were longest in obstructive HCM ( all P ＜ 0 .05 ) . Additionally ,the exercise time of the control group was the longest , followed by non‐obstructive and labile‐obstruction HCM ,and the shortest in the obstructive HCM ( all P ＜0 .05) . T he M ET s of obstructive HCM were significantly lower than the other three groups ( all P ＜0 .05) . Conclusions In obstructive HCM ,the left ventricular systolic strain and synchronization ,as well as the M APSE ,are significantly impaired in patients both at rest and during exercise . T he patients with labile‐obstructive and non‐obstructive HCM have reduced left ventricular GLS , twist ,and e′,but normal left ventricular GCS ,GRS ,synchrony ,and M APSE at rest ,which are all impaired during exercise .

Quantification of left ventricular performance in different phenotypes of hypertrophic cardiomyopathy / 中华超声影像学杂志

Objective@#To evaluate the characteristics of left ventricular structure, function, myocardial mechanics, hemodynamics and synchrony in different phenotypes of hypertrophic cardiomyopathy (HCM) using state-of-the-art echocardiography.@*Methods@#A consecutive series of 85 adult HCM patients who were admitted to the Xi Jing HCM center from January 2016 to November 2017 were collected. According to the peak left ventricular outflow tract pressure gradient in exercise stress echocardiography, the patients were divided into three groups: patients with non-obstructive HCM (n=28), those with labile-obstructive HCM (n=27), and those with obstructive HCM (n=30). In addition, 16 normal family members of HCM patients were included as control group. Two-dimensional speckle tracking imaging, tissue Doppler imaging and exercise stress echocardiography were used to evaluate the left ventricular function in resting and exercise states.@*Results@#①As compared with the control group, left ventricular end-diastolic diameter decreased and left ventricular ejection fraction increased in all three HCM groups(all P<0.05). Left ventricular maximum wall thickness and left ventricular mass index were the highest in obstructive HCM, followed by labile-obstructive and non-obstructive HCM, and the lowest in the control group (all P<0.05). ②At rest, the left ventricular global longitudinal, circumferential and radial strain (GLS, GCS and GRS), as well as the twist of obstructive HCM were significantly lower than the other three groups (all P<0.05). As compared with the control group, the GLS and twist decreased in the labile-obstructive and non-obstructive HCM(all P<0.05), but there were no significant changes of GCS and GRS (all P>0.05). The obstructive HCM had the lowest mitral annular plane systolic excursion (MAPSE) and s′, and the longest systolic peaking time standard deviation(Ts-SD) and early diastolic peaking time standard deviation(Te-SD) (all P<0.05). The left ventricular diastolic function of obstructive HCM (e′, the E/e′ ratio and the left atrial volume index) was the worst, labile-obstruction and non-obstructive HCM were better, and the control group was the best (all P<0.001). ③During exercise, the GLS, GCS, GRS, twist of the left ventricle and the MAPSE were the lowest in the obstructive HCM, which increased in the labile-obstructive and non-obstructive HCM, and were best in the control group. The Ts-SD and Te-SD were the shortest in the control group, were prolonged in non-obstructive and labile-obstruction HCM, and were longest in obstructive HCM (all P<0.05). Additionally, the exercise time of the control group was the longest, followed by non-obstructive and labile-obstruction HCM, and the shortest in the obstructive HCM (all P<0.05). The METs of obstructive HCM were significantly lower than the other three groups (all P<0.05).@*Conclusions@#In obstructive HCM, the left ventricular systolic strain and synchronization, as well as the MAPSE, are significantly impaired in patients both at rest and during exercise. The patients with labile-obstructive and non-obstructive HCM have reduced left ventricular GLS, twist, and e′, but normal left ventricular GCS, GRS, synchrony, and MAPSE at rest, which are all impaired during exercise.

The change of left ventricular function and mechanical dispersion in patients with hypertrophic cardiomyopathy :a study with exercise stress echocardiography / 中华超声影像学杂志

To investigate the association between the change of left ventricular ( LV ) function and mechanical dispersion ( MD ) and exercise capacity in patients with hypertrophic cardiomyopathy ( HCM ) by exercise stress echocardiography . Methods Sixty‐five HCM patients [ 40 cases of hypertrophic non‐obstructive cardiomyopathy ( HNCM ) , 25 cases of hypertrophic obstructive cardiomyopathy ( HOCM ) ] and 25 control subjects were recruited .LV function ,MD and exercise capacity were evaluated by two‐dimensional speckle‐tracking imaging and echocardiography at rest and during exercise ,and the following parameters of LV function were recorded : LV global longitudinal strain ( LVGLS) ,MD ,early diastolic strain rate ( Sre) ,the ratio of peak early diastolic mitral inflow and annulus velocity ( E/e′) ,LV outflow tract gradient ( LVO TG) ; LV functional reserve was assessed by ΔLVGLS and ΔSRe ; exercise capacity was evaluated by metabolic equivalents ( M ET s ) . T he association between the change of LV function and MD and exercise capacity was investigated . Results ①Compared with normal controls ,LVO TG ,E/e′ and MD increased ,and LVGLS ,Sre , ΔLVGLS , ΔSRe and M ET s decreased in HNCM patients at rest and during exercise ( all P ＜ 0 .05 ) . ② LVO TG , E/e′ and MD were further increased ,LVLGS ,Sre ,ΔSRe and M Ets were further reduced in HOCM patients compared with HNCM patients ( all P ＜ 0 .05 ) . ③LVGLS and MD measured at peak exercise were associated with M ET s ( r ＝－0 .68 , P ＜ 0 .001 ; r ＝ －0 .43 , P ＜ 0 .001 ) . ④ ROC curve analysis showed LVGLS had a better predictive value for exercise intolerance in HCM patients ,followed by E/e′ and MD . Conclusions LV function and mechanic reserve are reduced but MD is increased in HCM patients ,especially in HOCM patients . Exercise capacity is associated with LV function and MD ,w hich can predict the reduced exercise capacity in HCM patients .

Changes of serum cortisol and IL-6 levels before and after exercise stress test and their relationship with white coat hypertension / 国际检验医学杂志

Objective To investigate the changes of serum cortisol and IL-6 levels before and after exercise stress test and their relationship with white coat hypertension .Methods A total of 48 patients with white coat hypertension in Liwan Hospital of Tra-ditional Chinese Medicine from January 2014 to August 2016 were selected as the study group ,30 cases of patients with common hypertension in the same period were selected as common group ,30 cases of healthy volunteers in the same period were selected as control group .All the objects in the three groups completed exercise stress test on an empty stomach ,sat on the power bicycle and pedaling 2 min with 200 W ,and after intermittent 5 min repeated exercise until extreme fatigue .Serum cortisol and IL-6 levels ,mean arterial pressure(MAP) of 3 groups before exercise ,immediately after exercise and 3 h after exercise were detected and compared . Value of serum cortisol and IL-6 on diagnosing white coat hypertension and its relationship with MAP were analyzed .Results Compared with the control group ,serum cortisol ,IL-6 levels and MAP of the study group and common group before and after exer-cise were increased .Compared with the common group ,serum cortisol and IL-6 levels and MAP of the study group were significant-ly increased immediately after exercise and 3 h after exercise (P<0 .05) .Compared with before exercise ,serum cortisol and IL-6 levels and MAP of the study group immediately after exercise and 3 h after exercise were increased(P<0 .05) .ROC curve analysis showed that it′s value to detecting serum cortisol and IL-6 levels before and after exercise stress test for diagnosing white coat hy-pertension ,in which the value of combined detection of serum cortisol and IL-6 immediately after exercise for diagnosing white coat hypertension was the best .Pearson linear correlation analysis showed that serum cortisol and IL-6 levels before and after exercise stress test were positively correlated with MAP of patients with white coat hypertension (r=0 .844 ,0 .802 ,P<0 .05) .Conclusion It′s value to detecting serum cortisol and IL-6 levels before and after exercise stress test for diagnosing white coat hypertension , which are related with blood pressure ,and could be used as reference indexes for the diagnosis and illness severity evaluation of white coat hypertension .

Changes of serum cortisol and IL-6 levels before and after exercise stress test and their relationship with white coat hypertension / 国际检验医学杂志

Objective To investigate the changes of serum cortisol and IL-6 levels before and after exercise stress test and their relationship with white coat hypertension .Methods A total of 48 patients with white coat hypertension in Liwan Hospital of Tra-ditional Chinese Medicine from January 2014 to August 2016 were selected as the study group ,30 cases of patients with common hypertension in the same period were selected as common group ,30 cases of healthy volunteers in the same period were selected as control group .All the objects in the three groups completed exercise stress test on an empty stomach ,sat on the power bicycle and pedaling 2 min with 200 W ,and after intermittent 5 min repeated exercise until extreme fatigue .Serum cortisol and IL-6 levels ,mean arterial pressure(MAP) of 3 groups before exercise ,immediately after exercise and 3 h after exercise were detected and compared . Value of serum cortisol and IL-6 on diagnosing white coat hypertension and its relationship with MAP were analyzed .Results Compared with the control group ,serum cortisol ,IL-6 levels and MAP of the study group and common group before and after exer-cise were increased .Compared with the common group ,serum cortisol and IL-6 levels and MAP of the study group were significant-ly increased immediately after exercise and 3 h after exercise (P<0 .05) .Compared with before exercise ,serum cortisol and IL-6 levels and MAP of the study group immediately after exercise and 3 h after exercise were increased(P<0 .05) .ROC curve analysis showed that it′s value to detecting serum cortisol and IL-6 levels before and after exercise stress test for diagnosing white coat hy-pertension ,in which the value of combined detection of serum cortisol and IL-6 immediately after exercise for diagnosing white coat hypertension was the best .Pearson linear correlation analysis showed that serum cortisol and IL-6 levels before and after exercise stress test were positively correlated with MAP of patients with white coat hypertension (r=0 .844 ,0 .802 ,P<0 .05) .Conclusion It′s value to detecting serum cortisol and IL-6 levels before and after exercise stress test for diagnosing white coat hypertension , which are related with blood pressure ,and could be used as reference indexes for the diagnosis and illness severity evaluation of white coat hypertension .

Ecuación más conveniente para predecir frecuencia cardíaca máxima esperada en esfuerzo / More convenient equation for predicting maximum heart rate expected in exercise testing / Equação mais conveniente para prever frequência cardíaca máxima esperada em teste de esforço

Objetivo. Comparar la frecuencia cardíaca máxima (FCmax) alcanzada con la esperada según la fórmula clásica (220 menos edad) y la propuesta por Tanaka [208,75 - (0,73 x edad)] en diferentes poblaciones para determinar cuál es la ecuación más exacta, en vista de que este parámetro es muy utilizado para la evaluación de la reserva cronotrópica y coronaria. Material y método. Estudio descriptivo, observacional y transversal con 910 pacientes que realizaron prueba ergométrica graduada en el Instituto Médico Río Cuarto (Córdoba, Argentina) durante 2012-2013. Se utilizó el protocolo de Astrand. Se evaluó la FCmax alcanzada y esperada de cada paciente mediante la fórmula clásica y la de Tanaka. Se compararon dichos resultados según el género, rango etario, índice de masa corporal (IMC), presencia de factores de riesgo (hipertensión arterial, diabetes mellitus, dislipidemia, enfermedad coronaria previa y/o tabaquismo) y consumo de beta bloqueantes. Para el análisis estadístico se utilizó Microsoft Excel y SPSS, y la probabilidad estadística mediante el índice de Pearson con un valor <0,01. Resultados. Se analizaron 910 pacientes, 554 (61%) de género masculino y 356 (39%) femenino, la edad promedio fue de 47±16 años, el IMC fue de 27±5. El 48% de la población presentó uno o más factores de riesgo y el 15% estaba bajo tratamiento con beta bloqueantes. Al analizar la FCmax alcanzada por el paciente y compararla con la esperada según ambas fórmulas, se halló una sobreestimación por parte de las mismas, resultando más precisa en los menores de 40 años, la de Tanaka, y en los mayores de 40 años, la fórmula clásica. En los pacientes con IMC >25 y en los tratados con beta bloqueantes, se evidenció una sobreestimación de la FCmax esperada con ambas fórmulas. Conclusiones. La fórmula de Tanaka fue más precisa en los pacientes menores de 40 años sin diferencias respecto al género, por lo que sugerimos utilizar esta ecuación para dicha población y reservar la clásica para los mayores de 40 años. Esta relación se mantuvo en las subpoblaciones según presencia o no de factores de riesgo e IMC. Estos hallazgos tendrían el efecto de subestimar el verdadero nivel de estrés físico impuesto durante la prueba de esfuerzo y la intensidad adecuada de los programas de ejercicios prescriptos. La población que utilizaba beta bloqueantes presentó una sobreestimación con ambas fórmulas, siendo más acentuada cuanto más joven era el paciente.

Objective. To compare the maximum heart rate (HRmax) reached with the expected according to the classical formula (220 minus age) and that proposed by Tanaka [208,75 - (0,73 x age)] in different populations to determine which is the most accurate equation, given that this parameter is used to evaluate the chronotropic and coronary reserve. Material and method. Descriptive, observational and cross-sectional study with 910 patients who underwent exercise stress test graduated at the Medical Institute Rio Cuarto (Cordoba, Argentine) during 2012-2013. Åstrand protocol was used. HRmax achieved and expected of each patient by the classic formula and Tanaka's formula were evaluated. These results were compared by gender, age range, body mass index (BMI), presence of risk factors (hypertension, diabetes mellitus, dyslipidemia, previous coronary disease and/or smoking) and use of beta blockers. Microsoft Excel for statistical analysis and SPSS was used, and the statistical probability by Pearson index with a value <0.01. Results. The 910 patients, 554 (61%) of male and 356 (39%) female, mean age was 47±16 years, BMI was 27±5 were analyzed. The 48% of the population had one or more risk factors and 15% were treated with beta blockers. When analyzing the HRmax reached by the patient and compared with the expected according to both formulas, an overestimation was found by them, resulting in more accurate Tanaka's formula in the under 40 years and the classic formula those over 40 years. In patients with BMI >25 and in those treated with beta blockers, an overestimation of HRmax expected with both formulas was evidenced. Conclusions. Tanaka's formula was more accurate in patients younger than 40 years without sex differences, so we suggest using this equation for this population and reserve the classic formula for over 40 years. This relationship remained in subpopulations according to presence or absence of risk factors and BMI. These findings would have the effect of underestimating the true level of physical stress imposed during the stress test and the right intensity of exercise prescribed programs. The population using beta blockers showed an overestimation with both formulas, being more pronounced the younger was the patient.

Objetivo. Comparar a frequência cardíaca máxima (FCmax) alcançada com a esperada de acordo com a fórmula clássica (220 menos a idade) e o proposto por Tanaka [208,75 - (0,73 x idade)] em populações diferentes para determinar qual é a equação mais precisa, uma vez que este parâmetro é utilizado para avaliar da reserva cronotrópica e coronária. Material e método. Estudo descritivo, observacional e transversal, com 910 pacientes que foram submetidos a teste progressivo de esforço no Instituto de Medicina do Rio Cuarto (Córdoba, Argentina) durante 2012-2013. Foi utilizado o protocolo de Åstrand. Foi avaliada a FCmax alcançada e esperada de cada paciente pela fórmula clássica e fórmula de Tanaka. Estes resultados foram comparados por sexo, faixa etária, índice de massa corporal (IMC), a presença de fatores de risco (hipertensão arterial, diabetes mellitus, dislipidemia, doença coronariana prévia e/ou tabagismo) e consumo de beta-bloqueadores. Para análise estatística foi utilizada Microsoft Excel e SPSS, e a probabilidade estatística pelo índice de Pearson, com um valor <0,01. Resultados. Foram analisados 910 pacientes, 554 (61%) do sexo masculino e 356 (39%) do sexo feminino, com idade média de 47±16 anos, o IMC foi de 27±5. O 48% da população apresentaram um ou mais fatores de risco e 15% foram tratados com betabloqueadores. Ao analisar a FCmax alcançada pelo paciente e comparada com a esperada de acordo com ambas as fórmulas, uma superestimação foi encontrada por eles, resultando mais precisa a fórmula Tanaka em menores de 40 anos e a fórmula clássica em pessoas com mais de 40 anos. Em pacientes com IMC >25 e naqueles tratados com betabloqueadores, foi demonstrada uma superestimação da FCmax esperada com ambas as fórmulas. Conclusões. A fórmula de Tanaka foi mais precisa em pacientes com menos de 40 anos sem diferenças entre os sexos, por isso sugerimos usar esta equação para essa população e fórmula clássica para os maiores de 40 anos. Esta relação manteve-se em subpopulações de acordo com a presença ou a ausência de fatores de risco e IMC. Estes achados teriam o efeito de subestimar o verdadeiro nível de estresse físico imposta durante o teste de esforço e a intensidade certa de programas de exercício prescrito. A população utilizando betabloqueadores demonstrou uma superestimação com as duas fórmulas, sendo mais pronunciada quanto mais jovem foi o paciente.

Head to Head Comparison of Stress Echocardiography with Exercise Electrocardiography for the Detection of Coronary Artery Stenosis in Women

BACKGROUND: Exercise-stress electrocardiography (ECG) is initially recommended for the diagnosis of coronary artery disease. But its value has been questioned in women because of suboptimal diagnostic accuracy. Stress echocardiography had been reported to have comparable test accuracy in women. But the data comparing the diagnostic accuracy of exercise-stress ECG and stress echocardiography directly are few. The aim of the study was to compare the diagnostic accuracy of exercise-stress ECG and dobutamine stress echocardiography (DSE) in Korean women. METHODS: 202 consecutive female patients who presented with chest pain in outpatient clinic, and who underwent treadmill exercise test (TET), DSE and coronary angiography were included for the study. The diagnostic accuracy TET and DSE were calculated by the definition of > 50% or > 75% coronary artery stenosis (CAS). RESULTS: The sensitivity and specificity were higher with DSE (70.4, 94.6%) than TET (53.7, 73.6%) for detection of > 50% CAS. The higher accuracy of DSE was maintained after exclusion of the patients who could not achieve over 85% age predicted heart rate before ischemia induction. DSE also showed greater diagnostic accuracy than TET by > 75% CAS criteria, and in subsets of patient with intermediate pretest probability. CONCLUSION: In the diagnosis of CAS, DSE showed higher accuracy than TET in female patients who presented with chest pain. As well as the test accuracy, adequate stress was more feasible with DSE than TET. These finding suggests DSE may be used as the first-line diagnostic tool in the detection of CAS in women with chest pain.

Analysis of the correlation between electrocardiogram exercise stress test and coronary artery stenosis degree / 中国医师进修杂志

Objective To analyze the correlation between electrocardiogram exercise stress test and coronary artery stenosis degree.Methods A total of 150 patients who performed electrocardiogram exercise stress test were selected,and then coronary angiography were performed within 2 weeks.The sensitivity,specificity,positive predictive value and accuracy of electrocardiogram exercise stress test for diagnosing coronary artery stenosis degree were analyzed.Results Compared with coronary angiography,the sensitivity,specificity,positive predictive value and accuracy of electrocardiogram exercise stress test for diagnosing coronary heart disease were 75％(48/64),74％ (64/86),69％(48/70) and 75％ (112/150),respectively,for diagnosing coronary artery disease were 31％ (19/62),42％ (37/88),27％ (19/70) and 37％ (56/150),respectively.Conclusions Electrocardiogram exercise stress test as a simple,feasible and noninvasive method,has a good concordance with coronary angiography and a high correlation with coronary heart disease,a low correlation with coronary artery disease.It can be used as a good way to screen patients with coronary heart disease.

A case of fitness to work in a worker with COPD using the exercise stress test

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease characterized by persistent airflow limitation. Therefore, both work ability and workday length may be affected in individuals with this disease. We studied a worker with suspected COPD and assessed fitness to work using post-bronchodilator spirometry, symptom assessment scales, and the exercise stress test. CASE REPORT: The patient was a 58-year-old man due to work as a field supervisor in the ship construction sector. He had a 40 pack-year smoking history and experienced occasional dyspnea when climbing stairs. He visited this hospital to receive cardiopulmonary function tests and to determine his ability to work. Post-bronchodilator spirometry revealed severe irreversible airway obstruction corresponding to a modified Medical Research Council grade of 2 on the dyspnea scale. His COPD Assessment Test score was 12, placing him in patient group D (high risk, more symptoms) based on the Global Initiative for Chronic Obstructive Lung Disease classification system. His maximum oxygen uptake (VO2max) was determined to be 19.16 ml/kg/min, as measured by the exercise stress test, and his acceptable workload for 8 h of physical work was calculated to be 6.51 ml/kg/min. His work tasks required an oxygen demand of 6.89 ml/kg/min, which exceeded the acceptable workload calculated. Accordingly, he was advised to adjust the work tasks that were deemed inappropriate for his exercise capacity. CONCLUSION: As COPD incidence is expected to rise, early COPD diagnosis and determination of fitness to work is becoming increasingly important. Performing the exercise stress test, to evaluate the functional capacity of workers with COPD, is considered an acceptable solution.

El análisis del intervalo QT corregido incrementa la capacidad de la ergometría para diagnosticar enfermedad arterial coronaria significativa / The Analysis of the Corrected QT-Interval Increases Exercise Stress Test Capability to Detect Significant Coronary Artery Disease

Introducción: La utilidad clínica de la capacidad de la ergometría para indicar la presencia y gravedad funcional de las obstrucciones coronarias se ve limitada por las relativamente bajas sensibilidad y especificidad del infradesnivel del segmento ST (infra-ST), lo cual hace necesaria la investigación de las modificaciones de otras variables electrocardiográficas durante el esfuerzo que puedan aportar información adicional y complementaria a la del infra-ST. Se ha demostrado que el evento más temprano en la primera fase de la lesión transmural es la prolongación del intervalo QT corregido (QTc). Objetivos: Investigar si las modificaciones del intervalo QTc inducidas por el esfuerzo máximo (QTc máx) sumadas al infra-ST ≥ 1 mm permiten incrementar la capacidad de la ergometría para diagnosticar la presencia de enfermedad arterial coronaria significativa y si otros signos pueden aportar también información útil para identificar a estos pacientes. Material y métodos: Ciento sesenta y seis pacientes con infra-ST ≥ 1 mm durante la fase de ejercicio y/o recuperación de una ergometría a los que posteriormente se les realizó una coronariografía se distribuyeron en dos grupos: Grupo I (GI): 118 pacientes que mostraron prolongación del intervalo QTc máx y Grupo II (GII): 48 pacientes que acortaron normalmente el QTc máx. Se analizaron parámetros clínicos, ergométricos y electrocardiográficos y la angiografía coronaria para comprobar la presencia de enfermedad arterial coronaria significativa. Resultados: En 102 de los 166 pacientes incluidos (61,4%) se diagnosticó enfermedad arterial coronaria significativa, todos ellos pertenecientes al GI. El GI mostró alta prevalencia de pacientes con enfermedad arterial coronaria significativa (86,4% vs. 0%; p < 0,001), bajo umbral isquémico, recuperación tardía del infra-ST, mayor ensanchamiento del complejo QRSmáx, incompetencia cronotrópica y baja tolerancia al ejercicio. Durante la prueba ergométrica graduada los pacientes del GII presentaron mayor prevalencia de hipertensión arterial grave y el infra-ST < 1 mm en el segundo minuto del posesfuerzo. El incremento del intervalo QTc máx resultó un predictor independiente de enfermedad coronaria (p < 0,001). Conclusiones: La prolongación del intervalo QTc máx sumado al infra-ST ≥ 1 mm incrementó notoriamente la capacidad de la prueba ergométrica graduada para diagnosticar la presencia de enfermedad arterial coronaria significativa, patología que estuvo ausente en todos los pacientes con infra-ST que acortaron normalmente el QTc máx.

Background: The clinical usefulness of exercise stress testing to indicate the presence and functional severity of coronary artery stenoses is limited by the relatively low sensitivity and specificity of ST-segment depression. Therefore, the modifications of other electrocardiographic variables during exercise, which may provide additional and complementary information to ST-segment depression, should be investigated. It has been demonstrated that the corrected QT interval (QTc) prolongation is the earliest event during the first stage of transmural ischemia. Objectives: The aim of this study was to investigate whether modifications of the QTc interval induced by maximal exercise (QTcmax) together with ST-segment depression ≥ 1 mm can increase the capability of the stress test to detect significant coronary artery disease and if other signs may also provide useful information to identify these patients. Methods: One hundred and sixty six patients with ST-segment depression ≥ 1 mm during exercise or during the recovery stage of a stress test underwent coronary angiography. They were divided into two groups: Goup I (GI): 118 patients with QTcmax interval prolongation and Group II (GII): 48 patients with normal QTcmax shortening. Clinical, stress test-related and electrocardiographic parameters and coronary angiography were analyzed to identify the presence of significant coronary artery disease. Results: Significant coronary artery disease was detected in 102 of the 166 patients included in the study (61.4%), all from GI. Group I showed high prevalence of patients with significant coronary artery disease (86.4% vs. 0%; p < 0.001), low ischemic threshold, late recovery of ST-segment depression, wider QRSmax complex, chronotropic incompetence and low exercise capacity. During graded exercise stress testing, GII patients presented greater prevalence of severe hypertension and ST-segment depression < 1 mm two minutes after exercise. Increased QTcmax interval resulted as an independent predictor of coronary artery disease (p < 0.001). Conclusions: QTcmax interval prolongation plus ST-segment depression ≥ 1 mm produced a considerable increase in the capability of exercise stress testing to detect significant coronary artery disease, which was absent in all the patients with ST-segment depression and normal QTcmax shortening.

El infradesnivel del segmento ST que se presenta o se profundiza durante la fase de recuperación: su aporte a la utilidad clínica de la ergometría / Clinical Usefulness of Exercise-Induced ST-Segment Depression Occurring or Increasing during the Recovery Phase / Clinical Usefulness of Exercise-Induced ST-Segment Depression Occurring or Increasing during the Recovery Phase

Introducción No obstante la disponibilidad actual de estudios por imágenes que brindan una muy buena capacidad diagnóstica y de evaluación, la prueba ergométrica graduada (PEG) está reconocida como un estudio importante y continúa siendo el procedimiento más utilizado para la evaluación, el diagnóstico y la estratificación de riesgo de los pacientes con enfermedad arterial coronaria (EAC). Objetivos 1) Investigar el valor clínico de la presencia durante una ergometría del infradesnivel del segmento ST (infra-ST) significativo que aparece sólo durante la fase de recuperación o del que es dudoso durante la fase de ejercicio pero que se profundiza tornándose positivo durante la fase de recuperación de la PEG y compararlos con el infra-ST significativo que se presenta durante la fase activa de ejercicio. 2) Evaluar los datos clínicos, ergométricos y de la angiografía coronaria de los pacientes. Material y métodos Se analizaron los datos clínicos y ergométricos de 147 pacientes con PEG positiva por infra-ST significativo, que en 94 pacientes (GI) se presentó durante la fase de ejercicio, en 29 (GII) sólo en la fase de recuperación y en 24 (GIII) fue dudoso durante el ejercicio, pero se profundizó tornándose significativo en la fase de recuperación. En cada grupo se realizó una correlación entre los resultados de la PEG y los hallazgos de la coronariografía. Resultados Se diagnosticó EAC significativa en 78 pacientes del GI (82,9%), 22 del GII (75,8%) y 21 del GIII (87,5%) (p = 0,52). El GIII reunió los pacientes de edad más avanzada y con alta prevalencia de dislipidemia, antecedente de infarto previo y lesión de tres vasos y/o del tronco de la coronaria izquierda. El GII presentó el mayor número de pacientes asintomáticos, con lesión de un vaso y alta prevalencia de historia familiar de EAC. Conclusiones No se observaron diferencias estadísticas en el porcentaje de pacientes con EAC significativa entre los grupos. Los pacientes del GIII mostraron alta prevalencia de enfermedad coronaria extensa y grave. La evaluación correcta del infra-ST que aparece o se profundiza durante la fase de recuperación aumentó la información clínica que aporta una ergometría.

Background Despite the current availability of diagnostic image tests with excellent diagnostic and prognostic accuracy, exercise stress testing (EST) remains as the procedure most commonly used for the evaluation, diagnosis and risk stratification of patients with coronary artery disease (CAD). Objectives 1) To investigate the clinical usefulness of significant exercise-induced ST-segment depression (ST-d) occurring or increasing during the recovery phase of exercise stress test and to compare it with significant ST-segment depression presenting during the active phase of exercise; 2) to evaluate the clinical data and the information provided by EST and coronary angiography. Material and Methods Clinical and EST data from 147 patients with positive stress test were analyzed. All patients had significant ST-segment depression and were divided into three groups: GI, 94 patients with ST-d during exercise; GII, 29 patients with ST-d only during the recovery phase; and GIII, 24 patients with borderline ST-d during exercise which became significant during the recovery phase. The results of the EST were correlated with the coronary angiography findings in each group. Results A diagnosis of significant CAD was made in 78 patients in GI (82.9%), in 22 in GII (75.8%) and in 21 in GIII (87.5%),(p = 0.52). Patients in GIII were older, with high prevalence of dyslipemia, history of previous infarction and three-vessel and/or left main coronary artery disease. GII presented the higher number of asymptomatic patients with one-vessel disease and high prevalence of CAD. Conclusions There were no statistical differences in the percentage of patients with significant CAD among the groups. Patients in GIII had high prevalence of significant and severe CAD. A proper evaluation of ST-d occurring or becoming significant during the recovery phase provided additional clinical information to the results of the EST.

Efeitos de um programa de exercícios sobre a capacidade funcional de pacientes com cardiopatia chagásica crônica / Efects of an exercise program on functional capacity of patients with chronic Chagas' heart disease

Introdução: Mesmo com todos os esforços para interrupção de sua transmissão, a doença de Chagas permanece como grave problema de saúde pública na América Latina, onde atinge entre 8 e 12 milhões de indivíduos. A cardiopatia chagásica crônica, principal responsável pela elevada morbimortalidade da doença, chega a acometer mais de meio milhão de brasileiros. Sua evolução pode atingir estágios graves de insuficiência cardíaca associada à perda de capacidade funcional e qualidade de vida, com grande impacto social e médico-trabalhista. Muitos estudos demonstram o resultado benéfico da prática regular de exercícios em cardiopatas, porém, há escassez de investigações em cardiopatia chagásica. Métodos: O presente estudo avaliou efeitos de um programa de exercícios sobre a capacidade funcional de 18 pacientes (13 mulheres) com cardiopatia chagásica crônica, com idade entre 30 e 72 anos, atendidos nos ambulatórios do Instituto de Pesquisa Clínica Evandro Chagas e do Instituto Nacional de Cardiologia, na cidade do Rio de JaneiroOs exercícios foram executados 3 vezes por semana, durante 1 hora (30 minutos de atividade aeróbica e 30 minutos de exercícios contra-resistência e alongamentos), ao longo de 6 meses, no ano de 2010. A avaliação da capacidade funcional foi realizada pela comparação da medida direta do VO2 obtido pelo Teste de Exercício Cardiopulmonar, antes e depois do programa. Para análise estatística foi utilizado o teste T de Student pareado e de Wilcoxon. Resultados: Os resultados mostram aumento médio do VO2pico acima de 10 porcento (p=0,01949). Conclusões: Os resultados sugerem melhora estatisticamente significativa da capacidade funcional com a prática regular de exercícios na população amostral...

Background: Despite all efforts to interrupt transmission, Chagas disease remains asevere public health problem in Latin America, affecting between 8 and 12 millionindividuals. The main cause for the high mortality of the disease is chronic Chagas'heart disease, which comes to affect more than half a million Brazilians. Its evolutionmay reach severe stages of heart failure associated with loss of functional capacity andquality of life, with enormous social and labor impact. Several studies have shown thebeneficial effect of regular exercise in cardiac patients, but few of them study Chagas'heart disease. Methods: This study evaluated the effects of an exercise program onfunctional capacity of 18 patients (13 women) with chronic Chagas' heart disease, agedbetween 30 and 72 years, treated in outpatient clinics of the Evandro Chagas Institute ofClinical Research and the National Institute of Cardiology in the city of Rio de Janeiro.The exercises were performed three times a week for one hour (30 minutes of aerobicactivity and 30 minutes of resistance exercise and stretching) over 6 months in the year2010. The functional capacity evaluation was performed by comparing directmeasurement of VO2 obtained by Cardiopulmonary Exercise Test before and after theprogram. The t Student and Wilcoxon tests were used to statistical analysis. Results:The results show an average increase in VO2 peak above 10 percent (p = 0.01949).Conclusions: The results suggest statistical significant improvement in functionalcapacity with regular exercise of the sample population...

Treadmill exercise testing of asymptomatic men and women without evidence of heart disease

The aim of this study was to test the hypothesis of differences in performance including differences in ST-T wave changes between healthy men and women submitted to an exercise stress test. Two hundred (45.4 percent) men and 241 (54.6 percent) women (mean age: 38.7 ¡À 11.0 years) were submitted to an exercise stress test. Physiologic and electrocardiographic variables were compared by the Student t-test and the chi-square test. To test the hypothesis of differences in ST-segment changes, data were ranked with functional models based on weighted least squares. To evaluate the influence of gender and age on the diagnosis of ST-segment abnormality, a logistic model was adjusted; P < 0.05 was considered to be significant. Rate-pressure product, duration of exercise and estimated functional capacity were higher in men (P < 0.05). Sixteen (6.7 percent) women and 9 (4.5 percent) men demonstrated ST-segment upslope ¡Ý0.15 mV or downslope ¡Ý0.10 mV; the difference was not statistically significant. Age increase of one year added 4 percent to the chance of upsloping of segment ST ¡Ý0.15 mV or downsloping of segment ST ¡Ý0.1 mV (P = 0.03; risk ratio = 1.040, 95 percent confidence interval (CI) = 1.002-1.080). Heart rate recovery was higher in women (P < 0.05). The chance of women showing an increase of systolic blood pressure ¡Ü30 mmHg was 85 percent higher (P = 0.01; risk ratio = 1.85, 95 percentCI = 1.1-3.05). No significant difference in the frequency of ST-T wave changes was observed between men and women. Other differences may be related to different physical conditioning.

The Selection of Exercise Stress Test in Hemiplegic Patients

OBJECTIVE: To suggest the standard tool for the selection of exercise stress tests (EST) by analysis of the initial evaluation factors affecting EST. METHOD: Twenty-two hemiplegic patients carried out treadmill, arm and bicycle ergometer ESTs. Treadmill EST using modified Harbor protocol was performed without taking off AFO. The velocity of the arm and bicycle ergometer was set in 50 rpm, and the resistance was increased up to 5 W at each stage. Each EST was completed at 80% of maximal heart rate. RESULTS: Brunnstrom stage of lower extrimity, Medical Research Council (MRC) scores [hip flexor, knee extensor, finger flexor] and standing balance of twelve patients completing treadmill EST were superior to those of failed group (p<0.05). Twelve patients completing bicycle ergometer EST showed significant differences in MRC scores [hip flexor, knee extensor] and sitting balance (p<0.05). Brunnstrom stage of lower extremity hip flexor and knee extensor power contributed mostly to the completion of treadmill EST (p<0.01). The completion of bicycle ergometer EST was mostly dependent on hip flexor and knee extensor power (p<0.01). CONCLUSION: For bicycle ergometer EST, hip flexor and knee extensor power should be higher than 3 and 4, respectively. Treadmill EST can be suggested when Brunnstrom stage of lower extremity, hip flexor and knee extensor power are above 4, 4 and 3, respectively. The completion rate of treadmill EST can be increased when standing balance ability and Brunnstrom hand score higher than 4 and 2, respectively.

Correlação entre o teste de caminhada de 6 minutos e as variáveis do teste ergométrico em pacientes com insuficiência cardíaca: estudo piloto / Correlation between six-minute walk test and exercise stress testing variables in patients with heart failure: a pilot study

Objetivo: Correlacionar a distância percorrida no teste de 6 minutos (TC6M) com as variáveis do testeergométrico (TE). Métodos: Foram estudados 21 pacientes, sendo 66%brancos, 62% homens, com média de idade de 60±11 anos, 38% diabéticos e com dislipidemia e 57% com hipertensãoarterial, com insuficiência cardíaca isquêmica (33%) e nãoisquêmica(67%), nas classes funcionais II (90%) e III (10%) da NYHA, com fração de ejeção = 0,35±0,058, utilizandoseo teste de caminhada de 6 minutos (TC6M) e o teste ergométrico (Bruce modificado). Foram excluídos ospacientes não otimizados com terapêutica medicamentosa,problemas ortopédicos, doença vascular periférica ou quaisquer limitações para esforço. Analisou-se no TC6Ma distância total percorrida, sendo o paciente submetido a 3 testes com intervalos de 20 minutos. Foi comparado o valor de distância média alcançada no TC6M com a distância percorrida no teste ergométrico; o consumo deoxigênio máximo (VO2) e o equivalente metabólico máximo (MET) do TE. Para a análise estatística foram utilizados: o teste do qui-quadrado, de Mann-Whitney e a correlação de Pearson. Resultados: Houve significativas correlações positivas entre a distância percorrida no TC6M e a distância percorrida no teste de esforço (p=0,0001; r=0,76); e entreo VO2 máximo (p=0,001; r=0,68) e o MET máximo (p=0,001; r=0,68) neste grupo de pacientes. Conclusão: O TC6M é um teste reprodutível, de fácil realização e de baixo custo que pode ser utilizado para a avaliação de pacientes com IC, podendo fornecer informações valiosas que normalmente são obtidassomente com o TE. O aumento da amostra poderá determinar o verdadeiro valor dessas informações.

Objective: To correlate the distance on Six-minute walk test (6-MWT) with parameters obtained during exercise stress testing (EST) with a Bruce-modified protocol. Methods: We studied 21 patients, of whom 66% were white, 62% male, age 60±11 years, 38% diabetic and with dyslipidemia and 57% with arterial hypertension, 33% with with ischemic and 67% with nonischemicHF, NYHA class II (90%) and III (10%), with ejection fraction= 0.35±0.058. We excluded patients with suboptimal therapy, orthopedic disability, peripheral vascular disease or unable to exercise. Patients weresubmitted to 6-MWT for three times, with a 20-minute interval, and mean distance value was considered forcomparisons with distance, maximal oxygen uptake (maxVO2) and maximal metabolic equivalent (MET) during EST. Chi-square, Mann-Whitney and Pearson’scorrelation tests were used. Results: We observed significant positive correlationsbetween mean distance on 6-MWT and EST distance (p=0.0001; r=0.76), EST maxVO2 (p=0.001; r=0.68) and EST MET (p=0.001; r=0.68). Conclusion: On heart failure patients, 6-MWT is a reproducible, low-cost and easily obtainable test that can provide valuable information, usually only available on EST. Future studies with larger samplesizes will validate the present study results.

Evaluation of Exercise Efficiency with Change in Oxygen Uptake and Work Rate in Stroke Patients

OBJECTIVE: To evaluate exercise capacity of subacute stroke patients with nonambulatory exercise stress test and to determine whether reduced exercise efficiency is associated with functional performance. METHOD: Experimental design was prospective and observational study. Eighteen patients with moderate to severe impairment after recent stroke performed exercise stress test by repeated knee flexion and extension exercise using isokinetic dynamometer. Work rate, oxygen consumption, heart rate were assessed during exercise stress test. The dynamic response, the ratio of change in oxygen uptake to change in work rate, was measured for correlation with FIM (Functional Independence Measure) scores. Occupational therapist recorded FIM scores on the day of transfer to inpatient rehabilitation unit and on discharge. Age-matched healthy group also performed exercise stress test in same settings. RESULTS: The patients group who had similar dynamic response with age-matched healthy group showed higher FIM scores than the patients group having higher dynamic response. CONCLUSION: Nonambulatory exercise stress test could be effectively used in subacute stroke patients and the ratio of change in oxygen uptake to change in work rate was a useful variable to reveal low exercise efficiency in subacute stroke patients who had a abnormal skeletal muscle metabolic capacity.