Agati L, Penco M, Sciomer S, Fedele F, Neja C P, Dagianti A
1st Department of Cardiology, University La Sapienza, Rome, Italy.
Int J Cardiol. 1989 Mar;22(3):321-7. doi: 10.1016/0167-5273(89)90273-8.
The mechanism responsible for the absence of anginal pain in patients who have episodes of both painless and painful myocardial ischemia, still remains unknown. Does the pain depend on an overstimulation of receptive structures or is this symptom the product of the excitation of a well-defined receptive system? The aim of this work is to test the first hypothesis: whether silent attacks are accompanied by the same degree of mechanical impairment as symptomatic ones. The authors compared the echocardiographic left ventricular functional behavior in the same patient (6 patients) during painful and painless myocardial ischemia. The echocardiographic changes observed during silent ischemic attacks were significantly different from those detected during symptomatic attacks. The latter were characterized by a larger extension of the ischemic myocardium and, as a consequence, by a larger functional impairment. Symptomatic and asymptomatic ischemic attacks were recorded echocardiographically in the same patient during repeated attacks on the same day, and were always clearly differentiated by the degree of wall motion abnormalities. The echocardiographic monitoring during the ischemic attack seemed to confirm that the greater functional impairment preceded the onset of pain leading to the occurrence of this symptom. Nevertheless, it was impossible to identify a threshold value above which the ischemic attack will be symptomatic. Our data seem to indicate a close relationship between painful ischemia and a higher degree of ischemic damage. Thus, in patients with predominantly painful myocardial ischemia, the extension and the severity of ischemia could play an important role in determining this symptom.
在同时有无痛性和疼痛性心肌缺血发作的患者中，导致无心绞痛疼痛的机制仍然未知。疼痛是取决于感受结构的过度刺激，还是这种症状是明确的感受系统兴奋的产物？这项工作的目的是检验第一个假设：无症状发作是否与有症状发作伴有相同程度的机械损伤。作者比较了同一患者（6例患者）在疼痛性和无痛性心肌缺血期间的超声心动图左心室功能表现。在无症状缺血发作期间观察到的超声心动图变化与有症状发作期间检测到的变化有显著差异。后者的特征是缺血心肌范围更大，因此功能损害更大。在同一天的重复发作期间，同一患者的有症状和无症状缺血发作通过超声心动图记录，并且总是通过壁运动异常程度清楚地区分。缺血发作期间的超声心动图监测似乎证实，更大的功能损害先于疼痛发作，导致出现这种症状。然而，不可能确定一个阈值，超过该阈值缺血发作将出现症状。我们的数据似乎表明疼痛性缺血与更高程度的缺血损伤之间存在密切关系。因此，在以疼痛性心肌缺血为主的患者中，缺血的范围和严重程度可能在决定这种症状方面起重要作用。
