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1.
Hypertension ; 51(4): 1163-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18259019

RESUMO

Exercise intolerance and heart failure with preserved ejection fraction are common in females. Recently, arterial stiffness has been suggested to be a significant contributor in the development of heart failure. How gender difference affects arterial stiffening and its response to exercise is not well known. We hypothesized that arterial elastance index during exercise would be more abnormal in females with hypertension than males. Arterial elastance index was estimated as arterial end systolic pressure/stroke volume controlled for body surface area and was measured at rest and during graded supine bicycle exercise (25 watts, 3-minute increments) in 298 patients with hypertension (149 males; 149 females; mean age, 59). The subjects were divided into 2 groups by gender. Exercise duration was significantly shorter in females compared to males (692+/-222 versus 483+/-128 seconds, P<0.001). Although arterial elastance index at baseline was significantly higher in males, the magnitude of increase was steeper in females with the magnitude of change at 75 W of exercise being significantly higher in females compared to males (0.69+/-0.83 versus 0.43+/-0.69, P=0.018). Arterial elastance index at each stage of exercise up to 75 W was independently associated with decreased exercise duration. In conclusion, despite lower arterial elastance index at rest, the increase during exercise was steeper in women with hypertension, suggesting a gender-related difference in dynamic arterial stiffness. The arterial elastance index during exercise was significantly associated with exercise duration in patients with hypertension.


Assuntos
Artérias/fisiologia , Exercício Físico/fisiologia , Insuficiência Cardíaca/fisiopatologia , Hipertensão/fisiopatologia , Caracteres Sexuais , Idoso , Pressão Sanguínea/fisiologia , Ecocardiografia Doppler , Elasticidade , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Volume Sistólico/fisiologia
2.
Circ J ; 72(2): 186-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18219151

RESUMO

BACKGROUND: It has been recently demonstrated that the hemodynamic consequences of exercise-induced increase in left ventricular (LV) filling pressure can be demonstrated noninvasively with supine bicycle exercise Doppler echocardiography. One of the practical drawbacks of Doppler echocardiography for assessing LV filling during exercise is the technical difficulty obtaining adequate signals for meaningful analysis during the rapid heart rates achieved during exercise. The purpose of this study was to assess LV filling pressures during the recovery period, as well as at rest, in healthy subjects to establish reference values of Doppler LV filling indices during recovery after exercise. METHODS AND RESULTS: Seventy-three healthy subjects (age 38+/-14 years, 62 males) underwent supine bicycle exercise. Mitral inflow and annular velocities were recorded at baseline and during recovery at 2, 5, and 10 min after cessation of exercise. The ratio of the mitral inflow early diastolic filling velocity (E) to the mitral annular early diastolic velocity (E') was used as an estimation of mean left atrial pressure (E/E'). The mean E/E' ratio at rest was 7.6+/-1.8 and it was <15 in all patients. Mean exercise duration was 837+/-184 s (range, 390-1,260). The E/E' ratio during recovery 2, 5, and 10 min after cessation of exercise was 8.8+/-1.9, 8.2+/-2.0 and 7.8+/-1.8, respectively, and none of the patients had an E/E' >15 during the recovery phase. CONCLUSION: In healthy subjects, the E/E' is less than 15 at rest, as well as during the recovery period up to 10 min after cessation of exercise. Because the E/E' is not elevated in healthy subjects, an elevated E/E' during the recovery period may be helpful for detecting exercise-induced diastolic dysfunction in subjects with tachycardia, even with low levels of exercise.


Assuntos
Pressão Sanguínea/fisiologia , Exercício Físico/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Ecocardiografia Doppler , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia/diagnóstico , Taquicardia/fisiopatologia , Fatores de Tempo , Função Ventricular
3.
Circ J ; 72(9): 1443-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18724019

RESUMO

BACKGROUND: Because the ratio of mitral inflow and annular velocity to stroke volume has been reported as an index of diastolic elastance (Ed), the hypothesis tested in the present study was that Ed during exercise would be more abnormal in female than in male patients with type 2 diabetes. METHODS AND RESULTS: Ed was measured at rest and during graded supine bicycle exercise (25W, 3-min increments) in 53 patients (27 males, mean age 53+/-14 years) with type 2 diabetes and 53 age- and gender-matched controls. The patients with diabetes were divided into 2 groups by gender. Ed was not significantly different at rest between men and women, but was significantly higher during exercise in women than in men (25 W, 0.15+/-0.04 vs 0.20+/-0.07, p=0.009; 50 W, 0.16+/-0.05 vs 0.21+/-0.08, p=0.0175). CONCLUSION: Left ventricular (LV) diastolic elastance is abnormal during exercise, but not at rest, in patients with diabetes without overt heart disease. Female gender was associated with increased LV stiffness during exercise among patients with type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Exercício Físico , Ventrículos do Coração/fisiopatologia , Valva Mitral/fisiopatologia , Caracteres Sexuais , Volume Sistólico , Adulto , Idoso , Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais
4.
Heart ; 93(12): 1571-6, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17449503

RESUMO

BACKGROUND: Subclinical myocardial dysfunction occurs in a significant number of patients with type 2 diabetes. Assessment of ventricular long-axis function by measuring mitral annular velocities using tissue Doppler echocardiography (TDE) is thought to provide a more sensitive index of systolic and diastolic function. We hypothesised that augmentation of left ventricular (LV) longitudinal contraction and relaxation during exercise would be blunted in patients with type 2 diabetes. METHODS: Mitral annular systolic (S') and early diastolic (E') velocities were measured at rest and during supine bicycle exercise (25 W, 3 min increments) in 53 patients (27 male, mean age 53+/-14 years) with type 2 diabetes and 53 subjects with age and gender-matched control. None had echocardiographic evidence of resting or inducible myocardial ischaemia. RESULTS: There were no significant differences in mitral inflow velocities at rest between the two groups. E' and S' at rest were also similar between the groups. However, S' (7.1+/-1.3 vs 8.3+/-1.8 cm/s at 25 W, p = 0.0021; 8.1+/-1.5 vs 9.1+/-2.0 cm/s at 50 W, p = 0.026) and E' (8.5+/-2.3 vs 9.9+/-3.1 cm/s at 25 W, p = 0.054; 9.1+/-2.1 vs 10.9+/-2.5 cm/s at 50 W, p = 0.0093) during exercise were significantly lower in patients with diabetes compared with controls. Longitudinal systolic and diastolic function reserve indices were significantly lower in patients with diabetes compared with that of controls (systolic index, 0.6+/-0.70 vs 1.2+/-1.5 cm/s at 25 W, p = 0.029; 1.2+/-1.2 vs 2.1+/-1.6 cm/s at 50 W, p = 0.009; diastolic index, 1.9+/-1.2 vs 2.5+/-2.2 cm/s at 25 W, p = 0.07; 2.3+/-1.3 vs 3.2+/-2.2 cm/s at 50 W, p = 0.031). CONCLUSION: In conclusion, unlike resting mitral inflow and annular velocities, changes of systolic and diastolic velocities of the mitral annulus during exercise were significantly reduced in patients with type 2 diabetes compared with the control group. The assessment of LV longitudinal functional reserve with exercise using TDE appears to be helpful in identifying early myocardial dysfunction in patients with type 2 diabetes.


Assuntos
Cardiomiopatias/diagnóstico por imagem , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Angiopatias Diabéticas/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Velocidade do Fluxo Sanguíneo , Diástole/fisiologia , Ecocardiografia Doppler/métodos , Exercício Físico/fisiologia , Teste de Esforço , Feminino , Ventrículos do Coração , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/fisiologia , Sístole/fisiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem
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