Analysis of Heart Rate Variability to Assess the Changes in Sympathovagal Balance after Acute Ischemic Stroke

• Main Authors: Chien- Fu Chen, 陳建甫
• Other Authors: Chiou-Lian Lai
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/29147522817657073393

碩士 === 高雄醫學大學 === 醫學系神經學科碩士班 === 97 === Cardiac autonomic dysfunction is a common complication after acute ischemic stroke (IS). Frequency-domain analysis of heart rate variability (HRV) has gained its popularity with broad applications as a functional indicator of autonomic nervous system. The aim of this study was to investigate the changes in sympathovagal balance and a possible localization dependent difference after acute IS. We studied 75 consecutive acute IS patients with measurements of HRV and associated cardiac autonomic parameters compared to 81 control subjects. Of the 75 patients, 28 had right-sided hemispheric (RH) infarction, 29 had left-sided hemi -spheric (LH) infarction, and 18 had brainstem (BS) infarction. 81 age-matched normal controls (37 men and 44 women; mean age 56.83±8.35 years) were recruited from the hospital and general community. Measurements of HRV and associated parameters including supine and head-up tilt blood pressure and heart rate and the questionares of cardiovascular symptoms were performed in all subjects. Low frequency (LF), high frequency (HF) and HF% in stroke patients were lower than those of the control subjects. The value of LF%, LF/HF were significantly higher than those of the controls. The results revealed that acute IS cause the decrease of HRV and exaggerated sympathetic activation and reduced vagal activity. Comparison of HRV in different localization of stroke patients with controls showed significant differences in LF, HF, LF%, HF%, and LF/HF among stroke groups. Post-hoc comparison identified significant differences between BS versus controls in LF, HF, HF%, LF/HF and between LH versus controls in LF%, HF% and LF/HF. Acute IS causes damage to the cardiac autonomic system manifested on the HRV. Acute BS correlated with greatest reduced parasympathetic and increased sympathetic inpact. In addition, LH had more sympathovagal modulation compared to RH.