Ji Bingyang, Liu Mingzheng, Liu Jinping, Wang Guyan, Feng Wei, Lu Feng, Shengshou Hu
Department of Cardiopulmonary Bypass, Cardiovascular Institute & Fuwai Hospital, PUMC & CAMS, Beijing, China.
J Card Surg. 2007 Sep-Oct;22(5):394-400. doi: 10.1111/j.1540-8191.2007.00433.x.
Ischemic preconditioning (IPC) is commonly regarded as having a powerful internal protective effect on the organs. The mechanism of IPC is not clear yet, and the controversy over the benefits and protocol of IPC still continues. In this study, we used the sensitive and specific biochemical marker: cardiac troponin-I (CTnI) to evaluate whether IPC as an adjunct to intermittent cold blood cardioplegia (CBC) could reduce myocardial injury, as opposed to simple CBC during coronary artery bypass grafting (CABG).
From May 2003 to December 2003, 40 patients with three vessel coronary artery disease (CAD) and stable angina, receiving first-time elective CABG, were randomly divided into two equal groups: IPC plus CBC (IPC + CBC group, n = 20); and CBC (CBC group, n = 20). The patients in IPC + CBC group received two cycles of ischemia (two min) and reperfusion (three min) before myocardial arrest induced by CBC. The patients in CBC group received 10-minute normothermic cardiopulmonary bypass (CPB) before CBC arrest. Clinical outcomes were observed during and after the operation. Serial venous blood samples were obtained before induction, after CPB, and postoperatively 6, 12, 24, and 72 hours. Hemodynamic indexes were obtained before and after the bypass by the radial catheter and Swan-Ganz catheter.
In both groups, there were no differences regarding operative parameters. Compared to the baseline, the level of CTnI increased after CPB, peaked 6-12 hours (p < 0.01). Compared to IPC + CBC group, plasma concentrations of CTnI in CBC group were significantly higher at 6 and 12 hours (p < 0.05). CI recovery in IPC + CBC group was more significant than CBC group at 12 and 24 hours (p < 0.05). IPC + CBC also shortened the time of postoperative mechanical ventilation (p < 0.05) after surgery.
Compared to the simple CBC in lower-risk CABG patients, IPC as an adjunct to CBC reduced CTnI release, improved heart function after surgery, and shortened the time of recovery in CAD patients.
缺血预处理（IPC）通常被认为对器官具有强大的内在保护作用。IPC的机制尚不清楚，关于IPC的益处和方案的争议仍在继续。在本研究中，我们使用敏感且特异的生化标志物：心肌肌钙蛋白I（CTnI）来评估IPC作为间歇性冷血心脏停搏液（CBC）的辅助手段是否能减少心肌损伤，这与冠状动脉旁路移植术（CABG）期间单纯使用CBC形成对比。
从2003年5月至2003年12月，40例患有三支血管冠状动脉疾病（CAD）且稳定型心绞痛、接受首次择期CABG的患者被随机分为两组，每组20例：IPC加CBC组（IPC + CBC组）；以及CBC组（CBC组）。IPC + CBC组的患者在CBC诱导的心肌停搏前接受两个周期的缺血（两分钟）和再灌注（三分钟）。CBC组的患者在CBC停搏前接受10分钟的常温体外循环（CPB）。在手术期间和术后观察临床结果。在诱导前、CPB后以及术后6、12、24和72小时采集系列静脉血样。通过桡动脉导管和Swan - Ganz导管在体外循环前后获取血流动力学指标。
两组在手术参数方面无差异。与基线相比，CPB后CTnI水平升高，在6 - 12小时达到峰值（p < 0.01）。与IPC + CBC组相比，CBC组在6小时和12小时时CTnI的血浆浓度显著更高（p < 0.05）。IPC + CBC组在12小时和24小时时CI恢复比CBC组更显著（p < 0.05）。IPC + CBC还缩短了术后机械通气时间（p < 0.05）。
与低风险CABG患者单纯使用CBC相比，IPC作为CBC的辅助手段可减少CTnI释放，改善术后心脏功能，并缩短CAD患者的恢复时间。
