Heim C, Geel A, Münzer T, Angehrn W, Roelli H, Niederhauser H
Institut für Anästhesiologie, Kantonsspital St. Gallen.
Anaesthesist. 1996 Mar;45(3):220-4. doi: 10.1007/s001010050255.
Perioperative, mostly silent ischaemia in patients with coronary heart disease is difficult to detect by clinical examinations.
During the clinical evaluation (part I of this study) we monitored patients with prior myocardial infarction (MI) by continuous electrocardiographic (ECG) recording from the evening before until the first 24 h after operation. Excluded from Holter ECG studies were patients with a bundle branch block, pacemaker, valvular heart disease, cardiomyopathy, severe hypokalaemia, and digitalis treatment. Data were recorded with a Holter 8500 recorder (Marquette Electronics) using modified V2, V4, and V5 leads (Fig. 1). Holter tapes were analysed twice with a Holter computing system (Software 5.8, Marquette Electronics), first by a blinded technician and then by the authors themselves. We defined the following criteria as pathological ST segment changes and as ischaemic episodes [7]: horizontal or down-sloping ST depression of at least 1 mm or elevation of 2 mm of at least 1 min duration measured at the J-point plus 60 ms. To quantify individual levels of ischaemia we used the definition "ischaemic load" [3]: ischaemic min/h monitored per patient. The statistic evaluation did not differ from that used in part I.
Out of 160 patients, 100 could be examined by Holter monitoring. Because of technical problems we could not record a Holter ECG in 2 of 6 patients with reinfarction. We found one or more perioperative episodes of ST-segment depression in 25 patients (25%). Ischaemic episodes were detected in 15 patients preoperatively, in 12 intraoperatively, and in 10 postoperatively. Three patients had ischaemic episodes during all periods. Patients with pathological ST segments suffered significantly more reinfarctions (3 of 25 vs. 1 of 75 patients) and were older (mean age difference 7 years, P < 0.05). Patients with ischaemic episodes and a clinical diagnosis of reinfarction (n = 3) demonstrated a dramatic postoperative increase in ischaemic load. Preoperative use of beta-blocking agents did not influence the incidence of ischaemic events. The sensitivity of postoperative Holter ECG monitoring in the diagnosis of reinfarction was 50%, the specificity 92%.
Perioperative Holter ECG monitoring is time-consuming, expensive, not very sensitive, and therefore not generally applicable for all patients with prior MI.
冠心病患者围手术期大多为无症状性缺血，临床检查难以检测到。
在临床评估（本研究的第一部分）期间，我们对既往有心肌梗死（MI）的患者从术前晚开始直至术后首个24小时进行连续心电图（ECG）记录监测。排除有束支传导阻滞、起搏器、心脏瓣膜病、心肌病、严重低钾血症以及正在接受洋地黄治疗的患者进行动态心电图研究。使用改良的V2、V4和V5导联，通过动态心电图8500记录仪（马奎特电子公司）记录数据（图1）。动态心电图磁带由一名动态心电图计算系统（软件5.8，马奎特电子公司）分析两次，首先由一名不知情的技术人员分析，然后由作者本人分析。我们将以下标准定义为病理性ST段改变和缺血发作[7]：在J点加60毫秒处测量，水平或下斜型ST段压低至少1毫米或抬高2毫米，持续至少1分钟。为了量化个体缺血水平，我们使用“缺血负荷”的定义[3]：每位患者每小时监测到的缺血分钟数。统计学评估与第一部分使用的方法相同。
160例患者中，100例可通过动态心电图监测进行检查。由于技术问题，6例再梗死患者中有2例未能记录动态心电图。我们在25例患者（25%）中发现了一个或多个围手术期ST段压低发作。术前15例患者、术中12例患者和术后10例患者检测到缺血发作。3例患者在所有时期均有缺血发作。病理性ST段患者再梗死发生率显著更高（25例中有3例，而75例患者中有1例），且年龄更大（平均年龄差7岁，P<0.05）。有缺血发作且临床诊断为再梗死的患者（n = 3）术后缺血负荷显著增加。术前使用β受体阻滞剂不影响缺血事件的发生率。术后动态心电图监测诊断再梗死的敏感性为50%，特异性为92%。
围手术期动态心电图监测耗时且昂贵，敏感性不高，因此并非普遍适用于所有既往有心肌梗死的患者。
