Münzer T, Stimming G, Brücker B, Geel A, Heim C, Kreienbühl G
Institut für Anästhesiologie, Kantonsspital St. Gallen.
Anaesthesist. 1996 Mar;45(3):213-20. doi: 10.1007/s001010050254.
Patients with a prior myocardial infarction (MI) have a high risk of perioperative reinfarction compared with the normal population (5%-8% vs. 0.1%-0.7%) [10]. According to Rao [13], a reduction of this risk is possible when patients are monitored invasively and all haemodynamic parameters are kept within the physiological range. In most institutions it is not feasible to treat patients as Rao recommended: this would overstrain both hospital structure and financial resources. We studied the incidence of perioperative MI and other cardiac events in patients with prior MI. During the study period the anaesthesia and intensive care methods of our institution were neither changed nor influenced. In addition to this clinical evaluation, we performed perioperative Holter electrocardiographic monitoring and measured serum levels of the recently introduced marker troponin T (parts II and III).
Institutional informed consent was obtained. The study was planned prospectively. All patients with prior MI (156) and/or coronary artery bypass grafting (CABG) (4) who were scheduled for elective noncardiac surgery between April 1992 and March 1993 were included. The following information was acquired and tabulated: age, sex, body weight, preoperative risk factors, ASA classification, preoperative blood pressure, pulse rate, and ECG (interpreted by an independent cardiologist), serum electrolytes, haemoglobin, creatine kinase (CK), CKMB faction, creatinine. Preoperative regular medications, type of anaesthesia, type, site, and duration of surgery, and intraoperative haemodynamic changes were documented. The patients were divided into four groups depending on the time interval between MI and surgery (group I: 0-3 months, group II: 3-6 months, group III: > 6 months, group IV silent MI and prior CABG without infarction). We then studied the number of patients who developed a perioperative MI or died of cardiac causes within 7 postoperative days (n = 160). Because of early discharge of 21 patients, we could study the occurrence of cardiac events within 7 postoperative days in 139 patients only. Definitions of perioperative MI included [3]: changes of ST pattern (horizontal ST depression > 0.1 mV or elevation > 0.2 mV) during 30 s and longer; new T-negativation or Q-wave; pathological CKMB fraction (> or = 6% of total CK); and angina pectoris; two of these criteria were required to be positive (WHO). Definitions of cardiac events included: ischaemia: any reversible horizontal depression of the ST segment of more than 0.1 mV or any ST segment rise of more than 0.2 mV. Patients with bundle branch block (BBB) were excluded; angina pectoris: any chest pain that disappered after application of nitroglycerine; arrhythmia: any change from preoperative rhythm or appearence of ventricular premature beats; and left ventricular failure: clinical and radiological signs of ventricular failure. Statistical evaluation of the demographic data was performed by the Kruskall-Wallis test; categoric variables were examined using the chi 2 test and Fisher's exact test. P values of less than 0.05 were considered significant.
Six of the 160 patients with prior MI developed a perioperative MI (3.8%); 2 of them (33%) died of cardiac causes (3rd and 6th postoperative day). All of these patients were in groups III or IV (interval > 6 months). Forty-two patients had one or more other cardiac events; arrhythmias (22) and ischaemia (14) were most common. Intraoperative hypotension was associated with postoperative MI (5 of 58 vs. 1 of 102). Preoperative congestive heart failure (4 of 18 vs. 3 of 121) and major surgery (7 of 68 vs. 0 of 71) led more often to postoperative left ventricular failure. Patients who received beta-blocking agents preoperatively had significantly fewer ischaemic cardiac events (0 of 28 vs. 14 of 90, 21 patients excluded with BBB) but differed in mean age (67 vs. 71 years). The use of beta-blocking agents was not associated with a reducti
与正常人群相比，既往有心肌梗死（MI）的患者围手术期再梗死风险较高（5%-8%对0.1%-0.7%）[10]。根据饶[13]的研究，当对患者进行有创监测且所有血流动力学参数保持在生理范围内时，这种风险有可能降低。在大多数机构中，按照饶的建议治疗患者是不可行的：这将使医院结构和财政资源不堪重负。我们研究了既往有心肌梗死患者围手术期心肌梗死及其他心脏事件的发生率。在研究期间，我们机构的麻醉和重症监护方法既未改变也未受影响。除了这种临床评估外，我们还进行了围手术期动态心电图监测，并检测了最近引入的标志物肌钙蛋白T（第二和第三部分）的血清水平。
获得机构知情同意。该研究为前瞻性规划。纳入1992年4月至1993年3月期间计划进行择期非心脏手术的所有既往有心肌梗死（156例）和/或冠状动脉搭桥术（CABG）（4例）的患者。收集并列表以下信息：年龄、性别、体重、术前危险因素、ASA分级、术前血压、脉搏率和心电图（由独立心脏病专家解读）、血清电解质、血红蛋白、肌酸激酶（CK）、CKMB组分、肌酐。记录术前常规用药、麻醉类型、手术类型、部位和持续时间以及术中血流动力学变化。根据心肌梗死与手术之间的时间间隔将患者分为四组（第一组：0-3个月，第二组：3-6个月，第三组：>6个月，第四组：无症状心肌梗死和既往CABG无梗死）。然后我们研究了术后7天内发生围手术期心肌梗死或死于心脏原因的患者数量（n = 160）。由于21例患者提前出院，我们仅能研究139例患者术后7天内心脏事件的发生情况。围手术期心肌梗死的定义包括[3]：30秒及更长时间内ST段形态改变（水平ST段压低>0.1 mV或抬高>0.2 mV）；新的T波倒置或Q波；病理性CKMB组分（>或=总CK的6%）；以及心绞痛；这些标准中需两项为阳性（世界卫生组织）。心脏事件的定义包括：缺血：ST段任何可逆性水平压低超过0.1 mV或任何ST段抬高超过0.2 mV。有束支传导阻滞（BBB）的患者被排除；心绞痛：应用硝酸甘油后消失的任何胸痛；心律失常：术前节律的任何改变或室性早搏的出现；以及左心室衰竭：心室衰竭的临床和放射学体征。对人口统计学数据进行Kruskal-Wallis检验；分类变量使用卡方检验和Fisher精确检验进行检查。P值小于0.05被认为具有统计学意义。
160例既往有心肌梗死的患者中有6例发生围手术期心肌梗死（3.8%）；其中2例（33%）死于心脏原因（术后第3天和第6天）。所有这些患者均在第三组或第四组（间隔>6个月）。42例患者发生了一项或多项其他心脏事件；心律失常（22例）和缺血（14例）最为常见。术中低血压与术后心肌梗死相关（58例中的5例对102例中的1例）。术前充血性心力衰竭（18例中的4例对121例中的3例）和大手术（68例中的7例对71例中的0例）更常导致术后左心室衰竭。术前接受β受体阻滞剂治疗的患者缺血性心脏事件明显较少（28例中的0例对90例中的14例，21例有BBB的患者被排除），但平均年龄不同（67岁对71岁）。β受体阻滞剂的使用与降低……无关
