Quintana M, Lindvall K, Brolund F, Eriksson S V, Rydén L
Karolinska Institute, Department of Cardiology, South Hospital, Stockholm, Sweden.
Coron Artery Dis. 1995 Nov;6(11):865-73.
The aim of this study was to evaluate the prognostic significance of myocardial ischemia detected by ambulatory ECG monitoring (AEM) and exercise stress testing (ExT) following acute myocardial infarction.
The prognostic value of AEM versus ExT was studied prospectively in 74 patients with a recent acute myocardial infarction. Myocardial ischemia was diagnosed by the presence of ST-segment depression occurring during AEM or ExT 4 +/- 2 and 7 +/- 4 days after hospital admission respectively. ST-segment depression during AEM was defined as a horizontal/downsloping depression of > or = 0.1 mV from the reference baseline, measured 80 ms after the J point, elapsing > or = 1 min. ST-segment depression at ExT was determined as > or = 1mm horizontal or downsloping ST-segment depression in at least two consecutive ECG leads.
Twenty-two patients (30%) showed ST-segment depression during AEM and 34 (49%) on ExT. During a mean follow-up period of 3 years (36 +/- 15 months), 10 patients (45%) with ST-segment depression on AEM died compared with eight (15%) without; 12 patients (35%) with ST-segment depression on ExT died versus three (8%) without. Death or reinfarction occurred in 13 patients (59%) with ST-segment depression on AEM versus nine (17%) without, and in 13 patients (38%) with ST-segment depression on ExT compared with six (17%) without. Revascularization procedures were similar in patients with or without ST-segment depression during AEM and ExT. Cardiac events defined as death, nonfatal reinfarction or revascularization, occurred in 18 patients (82%) with ST-segment depression on AEM versus 20 (38%) without, and in 23 patients (68%) with ST-segment depression on ExT versus 11 (31%) without. Survival analysis using Kaplan-Meier curves showed that patients showing no ST-segment depression with either technique had longer survival times than did patients showing ST-segment depression on either AEM or ExT, or showing ST-segment depression with both techniques. This was also true when analyzing the cumulative survival rate until the occurrence of any endpoint. With multivariate regression analysis, ST-segment depression on AEM was the variable most strongly predictive of mortality, followed by ST-segment depression on ExT, hypertension, and diabetes.
These findings illustrate the ability AEM and Ext independently to predict long-term cardiac mortality and morbidity rates in patients recovering from acute myocardial infarction. The combined use of these techniques is useful for detecting patients at high risk after acute myocardial infarction.
本研究旨在评估动态心电图监测（AEM）和运动负荷试验（ExT）检测到的心肌缺血对急性心肌梗死后的预后意义。
前瞻性研究了74例近期发生急性心肌梗死患者中AEM与ExT的预后价值。分别在入院后4±2天和7±4天通过AEM或ExT期间出现ST段压低来诊断心肌缺血。AEM期间的ST段压低定义为从参考基线水平/下斜型压低≥0.1mV，在J点后80ms测量，持续≥1分钟。ExT时的ST段压低定义为至少两个连续心电图导联中水平或下斜型ST段压低≥1mm。
22例患者（30%）在AEM期间出现ST段压低，34例（49%）在ExT时出现ST段压低。在平均3年（36±15个月）的随访期内，AEM时出现ST段压低的10例患者（45%）死亡，而未出现的为8例（15%）；ExT时出现ST段压低的12例患者（35%）死亡，未出现的为3例（8%）。AEM时出现ST段压低的13例患者（59%）发生死亡或再梗死，未出现的为9例（17%）；ExT时出现ST段压低的13例患者（38%）发生死亡或再梗死，未出现的为6例（17%）。AEM和ExT期间有或无ST段压低的患者的血运重建手术情况相似。定义为死亡、非致死性再梗死或血运重建的心脏事件，AEM时出现ST段压低的18例患者（82%）发生，未出现的为20例（38%）；ExT时出现ST段压低的23例患者（68%）发生，未出现的为11例（31%）。使用Kaplan-Meier曲线进行的生存分析显示，两种技术均未出现ST段压低的患者比AEM或ExT出现ST段压低或两种技术均出现ST段压低的患者生存时间更长。在分析直至任何终点发生时的累积生存率时也是如此。多因素回归分析显示，AEM时的ST段压低是最能预测死亡率的变量，其次是ExT时的ST段压低、高血压和糖尿病。
这些发现表明AEM和ExT能够独立预测急性心肌梗死恢复患者的长期心脏死亡率和发病率。联合使用这些技术有助于检测急性心肌梗死后的高危患者。
