Sasaki R, Tani H, Sugisawa K, Iwasaki T
First department of internal medicine, Hyogo College of Medicine.
Nihon Rinsho. 1995 Jan;53(1):185-90.
Myocardial ischemia is characterized by ST depression on a standard electrocardiogram caused by shortening of the action potential duration (APD). We investigated whether shortening of the APD can be used as a screening criterion, in place of ST depression, to diagnose effort angina. Estimation of APD was made based on recovery time (RT) on a 16-lead system signal-averaged electrocardiogram (SAE). RT was defined as the interval between the onset of the QRS complex and the maximum positive value during the T wave of SAE. The values of RT measured at each lead were plotted on a graph to produce an electrocardiographic isochrone map. RT were significantly shortened in all electrocardiographic leads in patients with effort angina. Shortening in RT was especially marked in the right precordal leads and was shown to be a highly specific criterion for screening effort angina.
心肌缺血的特征是标准心电图上出现ST段压低，这是由动作电位时程（APD）缩短引起的。我们研究了APD缩短是否可用作筛查标准，以替代ST段压低来诊断劳力性心绞痛。基于16导联系统信号平均心电图（SAE）上的恢复时间（RT）来估计APD。RT定义为SAE的QRS波群起始点与T波期间最大正值之间的间期。将各导联测得的RT值绘制成图，以生成心电图等时线图。劳力性心绞痛患者所有心电图导联的RT均显著缩短。右胸前导联的RT缩短尤为明显，并且被证明是筛查劳力性心绞痛的高度特异性标准。
