Kalisnik Jurij M, Avbelj Viktor, Trobec Roman, Ivaskovic Daroslav, Vidmar Gaj, Troise Giovanni, Gersak Borut
Department of Cardiovascular Surgery, University Medical Center Ljubljana, Ljubljana, Slovenia.
Heart Surg Forum. 2007;10(4):E279-87. doi: 10.1532/HSF98.20071055.
Altered autonomic regulation after cardiac operations precipitates cardiac arrhythmias, affects repolarization, and increases the risk of sudden cardiac death. We sought to clarify how the 2 different techniques of coronary artery bypass grafting (CABG), namely conventional CABG using cardiopulmonary bypass (on-pump) and beating-heart CABG without cardiopulmonary bypass (off-pump), affect cardiac autonomic regulation and arrhythmic disturbances postoperatively.
We included 57 consecutive patients, 28 in the on-pump group and 29 in the off-pump group. The electro-cardiographic recordings were performed on the preoperative day and the fourth, seventh, and twenty-eighth day after operation. Fifteen-minute digital recordings were taken; one channel was used to record electrocardiogram and the other breathing. Detailed analyses of arrhythmia, heart rate, and heart rate variability indices were performed on respective days to assess sympathetic and parasympathetic modulation of the heart and relate it to detected arrhythmic disturbances.
Total power, low-frequency power, which indicates baroreceptor-mediated sympathetic modulation, and high-frequency power, indicating parasympathetic vagal modulation, declined significantly in both groups after CABG (P < .001); however, 7 days after CABG, total and high-frequency power were better preserved in the off-pump group. Mean RR interval was longer in the off-pump group at 7 (P= .006) and 28 days (P= .008) after surgery. The total incidence of arrhythmic events was higher in the on-pump group on the seventh day (P = .017, adjusted odds ratio = 8.6, 95% confidence interval 1.4-80.3).
The results show profound impairment of cardiac autonomic regulation after CABG, showing better preserved cardiac autonomic modulation 7 days after beating-heart revascularization. Evidence suggests that slower restoration of heart rate and increased incidence of arrhythmic events after CABG using cardiopulmonary bypass are the result not only of impaired cardiac autonomic regulation but also of the involvement of additional factors of nonautonomic origin.
心脏手术后自主神经调节改变会引发心律失常，影响复极化，并增加心源性猝死风险。我们试图阐明冠状动脉搭桥术（CABG）的两种不同技术，即使用体外循环的传统CABG（体外循环下）和不使用体外循环的心脏不停跳CABG（非体外循环下）如何影响术后心脏自主神经调节和心律失常。
我们纳入了57例连续患者，体外循环下组28例，非体外循环下组29例。在术前以及术后第4天、第7天和第28天进行心电图记录。进行15分钟的数字记录；一个通道用于记录心电图，另一个通道记录呼吸。在相应日期对心律失常、心率和心率变异性指标进行详细分析，以评估心脏的交感和副交感神经调节，并将其与检测到的心律失常相关联。
CABG后两组的总功率、指示压力感受器介导的交感神经调节的低频功率以及指示副交感迷走神经调节的高频功率均显著下降（P <.001）；然而，CABG后7天，非体外循环下组的总功率和高频功率得到了更好的保留。术后第7天（P =.006）和第28天（P =.008）非体外循环下组的平均RR间期更长。体外循环下组在第7天心律失常事件的总发生率更高（P = .017，调整后的优势比 = 8.6，95%置信区间1.4 - 80.3）。
结果表明CABG后心脏自主神经调节严重受损，心脏不停跳血运重建术后7天心脏自主神经调节得到更好的保留。有证据表明，体外循环下CABG后心率恢复较慢和心律失常事件发生率增加不仅是心脏自主神经调节受损的结果，也是非自主来源的其他因素参与的结果。
