冠脉搭桥术后病人心率变异性的变化

Changes in heart rate variability in patients after coronary artery bypass graft

目的 了解冠脉搭桥术后病人心率变异性 (HRV)的变化及其意义。方法 36例冠脉搭桥术病人 ,采用HXD I型电脑多功能监测仪监测 ,术前 1d、麻醉前、手术结束时、以及术后 3d和 6d的HRV。结果 术前 1d的HRV总功率对数值为 3 0 7± 0 35 ,其中低频 (LF)为 2 38± 0 47,高频 (HF)为2 37± 0 5 4,LF/HF比值为 1 34± 0 93。与术前比较 ,麻醉前HRV各指标无明显变化 (P >0 0 5 ) ,手术结束时低、高频、总功率均有所下降 ,分别为 2 18± 0 45、2 2 2± 0 6 0和 2 90± 0 37(P <0 0 5 )。术后第 3d进一步下降 ,分别为 1 70± 0 6 5、1 86± 0 6 5和 2 6 3± 0 41(P <0 0 5 ) 术后第 6d与术后第 3d基本维持在同一水平 (P >0 0 5 )。结论 冠脉搭桥术后病人的HRV降低可持续 6d以上 ,表明术后早期植物神经对心脏的调节作用较弱。

Objective To investigate the significance of the changes in heart rate variability (HRV) in patients undergoing coronary artery bypass graft procedure Methods Thirty six patients scheduled for elective coronary artery bypass were studied HRV was monitored by HXD I monitoring system one day prior to surgery (as baseline values), before anesthesia, at the end of surgery and on the 3rd day and 6th day after surgery Results The baseline logical values for total power(TP), low frequency (LF), high frequency (HF), LF/HF ratio were 3 07±0 35, 2 38±0 47, 2 37±0 54 and 1 34±0 93 respectively There were no significant changes in all these parameters before anesthesia as compared to baseline values LF,HF and TP decreased significantly on the 3rd day after surgery as compared with baseline values, and were kept at the level on the 6th postoperative day Conclusions The decrease in HRV power can last over 6 days after coronary bypass graft surgery, signifying reduced autonomous regulation of heart in the early postoperative days