Sutton J M, Topol E J
Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor 48109-0022.
Circulation. 1991 Apr;83(4):1278-86. doi: 10.1161/01.cir.83.4.1278.
After thrombolytic therapy for acute myocardial infarction, increasing emphasis is placed on early submaximal exercise testing, with further intervention advocated only for demonstrable ischemia. Although significant residual coronary artery lesions after successful thrombolysis are common, many patients paradoxically have no corresponding provokable ischemia.
The relation between significant postthrombolytic residual coronary artery disease and a negative early, submaximal exercise thallium-201 tomogram was studied among 101 consecutive patients with uncomplicated myocardial infarction and at least 70% residual stenosis of the infarct artery. A negative test occurred in 49 (48.5%) patients with a mean 88% residual infarct artery stenosis. Further characteristics of the group were as follows: mean time to treatment was 3.1 hours; mean age was 54 +/- 10 years; 80% were male; 47% had anterior infarction; 39% had multivessel disease; mean left ventricular ejection fraction was 53 +/- 14%; and mean peak creatine kinase level was 3,820 +/- 3,123 IU/ml. A similar group of 52 (51.5%) patients, treated within 3.3 hours from symptom onset, with a mean postthrombolysis stenosis of 90%, had a positive exercise test. Characteristics of this group were as follows: age was 58 +/- 10 years; 92% were male; 56% had anterior infarction; 40% had multivessel disease; and mean left ventricular ejection fraction was 54 +/- 15%. The peak creatine kinase level associated with the infarction, however, was lower: 2,605 +/- 1,805 IU/ml (p = 0.04). There was no difference in performance at exercise testing with respect to peak systolic pressure, peak heart rate, or time tolerated on the treadmill between the two groups. By multivariate logistic regression, only peak creatine kinase level predicted a negative stress result in the presence of a significant residual stenosis (odds ratio, 4.2; 95% confidence interval, 1.1-16.3).
The explanation for the relatively frequent finding of a negative early stress 201Tl tomogram after apparently successful reperfusion appears to be more extensive myocardial necrosis and not delay in therapy or inadequate exercise performance.
急性心肌梗死后进行溶栓治疗后，越来越强调早期次极量运动试验，仅对证实有心肌缺血的患者主张进一步干预。尽管溶栓成功后残留明显的冠状动脉病变很常见，但许多患者却反常地没有相应的可诱发的心肌缺血。
对101例无并发症的心肌梗死且梗死相关动脉残留狭窄至少70%的连续患者，研究溶栓后明显的残留冠状动脉疾病与早期次极量运动201铊心肌断层扫描阴性之间的关系。49例（48.5%）患者运动试验阴性，梗死相关动脉平均残留狭窄88%。该组的其他特征如下：平均治疗时间为3.1小时；平均年龄为54±10岁；80%为男性；47%为前壁梗死；39%有多支血管病变；平均左心室射血分数为53±14%；平均肌酸激酶峰值水平为3820±3123IU/ml。另一组52例（51.5%）患者，症状发作后3.3小时内接受治疗，溶栓后平均狭窄90%，运动试验阳性。该组的特征如下：年龄为58±10岁；92%为男性；56%为前壁梗死；40%有多支血管病变；平均左心室射血分数为54±15%。然而，与梗死相关的肌酸激酶峰值水平较低：2605±1805IU/ml（p=0.04）。两组在运动试验时的收缩压峰值、心率峰值或在跑步机上耐受的时间方面表现无差异。通过多因素逻辑回归分析，在存在明显残留狭窄的情况下，只有肌酸激酶峰值水平可预测应激结果为阴性（优势比，4.2；95%置信区间，1.1 - 16.3）。
在明显成功再灌注后早期应激201铊心肌断层扫描相对频繁出现阴性结果的原因，似乎是更广泛的心肌坏死，而非治疗延迟或运动表现不佳。
