Impaired baroreflex sensitivity and increased systolic blood pressure variability in chronic post-ischemic stroke

OBJECTIVES: Acute post-stroke patients present cardiovascular autonomic dysfunction, which manifests as lower heart rate variability and impaired baroreflex sensitivity. However, few studies performed to date have evaluated cardiovascular autonomic function in chronic post-stroke patients. The aim of this study was to evaluate cardiovascular autonomic modulation in chronic post-ischemic stroke patients. METHODS: The seventeen enrolled subjects were divided into a stroke group (SG, n=10, 5±1 years after stroke) and a control group (CG, n=7). Non-invasive curves for blood pressure were continuously recorded (Finometer®) for 15 minutes while the subject was in a supine position. Heart rate variability and blood pressure variability were analyzed in the time and frequency domains. RESULTS: No differences were observed in systolic and diastolic pressure and heart rate between post-stroke patients and healthy individuals. The SG group had lower indexes for heart rate variability in the time domain (standard deviation of normal to normal R-R intervals, SDNN; variance of normal to normal R-R intervals, VarNN; and root mean square differences of successive R-R intervals, RMSSD) and a lower high-frequency band for heart rate variability than was observed in the CG. Systolic blood pressure variability and the low-frequency band for systolic pressure were higher in post-stroke patients, while the alpha index was lower in the SG than in the CG. CONCLUSION: After ischemic stroke, affected patients present chronically reduced heart rate variability, impaired cardiac vagal modulation, increased systolic blood pressure variability and higher sympathetic vascular modulation along with impaired baroreflex sensitivity, which can increase the risk of cardiovascular events, despite adequate blood pressure control.

The effect of gait training and exercise programs on gait and balance in post-stroke patients / O efeito do treinamento de marcha e programas de exercícios na marcha e equilibrio postural em pacientes após acidente vascular encefálico crônico

The aim of this review is to evaluate studies about gait training and exercise interventions applied to patients following chronic stroke on gait and balance. The studies included in this review were random clinical trials, including only chronic post-stroke individuals that evaluated gait and balance outcomes and with a PEDro scale score ≥ 7.0. Eight studies were selected. The results suggest gait and balance will only be affected in chronic post-stroke patients if training sessions last at least 30 minutes, are repeated three times a week, and maintained for at least five weeks. Gait training affects how chronic post-stroke individuals walk. They will probably walk faster and with a lower risk of falling; however, it is unclear whether the consequences of these procedures affect the quality of life.

RESUMO O objetivo desta revisão é avaliar estudos sobre intervenções com treino de marcha e exercícios específicos sobre marcha e equilíbrio postural, aplicados a pacientes após acidente vascular encefálico em fase crônica. Os estudos incluídos nesta revisão foram ensaios clínicos randomizados, incluindo apenas indivíduos pós-acidente vascular encefálico em fase crônica que avaliaram marcha e equilíbrio postural, com uma pontuação em escala PEDro ≥ 7.0. Oito estudos foram selecionados. Os resultados sugerem que a marcha e o equilíbrio somente são afetados em pacientes crônicos pós-acidente vascular encefálico se as sessões de treinamento tiverem duração mínima de 30 minutos, forem repetidos três vezes por semana, e mantidos durante pelo menos cinco semanas. O treino de marcha e os exercícios afetam a forma como os indivíduos pós-acidente vascular encefálico em fase crônica andam. Eles provavelmente andarão mais rápido e com menor risco de quedas; no entanto, não está claro se as consequências destes procedimentos afetam a qualidade de vida.