Savvides M, Ahnve S, Bhargava V, Froelicher V
Chest. 1983 Dec;84(6):699-706. doi: 10.1378/chest.84.6.699.
In order to evaluate computerized methods of electrocardiographic signal processing, determination of QRS end, and measurement of criteria for ischemia, we analyzed the data from 42 male patients with coronary heart disease who underwent maximal treadmill testing. Electrocardiographic data were digitized on-line and leads X, V5, Y and Eigen V were later analyzed for noise content, isoelectric baseline, and ST parameters using the UCSD spatial electrocardiographic computer program. Various ST segment criteria for ischemia were calculated and compared. Noise was greater in lead Y and in all leads when the median was used for signal averaging. Two isoelectric baseline algorithms and three ST segment slope algorithms gave similar results. Spatially derived QRS end was highly correlated with the amplitude measured using a fixed time interval after peak R wave. Both ST area and ST midpoint estimates differed widely using two different algorithms for each. Regression equations were derived that make it possible to estimate QRS end or ST60 amplitudes in V5 from values in X or vice versa.
为了评估心电图信号处理的计算机化方法、QRS波终点的确定以及缺血标准的测量，我们分析了42例接受最大运动平板试验的男性冠心病患者的数据。心电图数据在线数字化，随后使用加州大学圣地亚哥分校空间心电图计算机程序对X、V5、Y导联和特征向量V进行噪声含量、等电位基线和ST段参数分析。计算并比较了各种缺血性ST段标准。当使用中位数进行信号平均时，Y导联和所有导联的噪声更大。两种等电位基线算法和三种ST段斜率算法得出了相似的结果。空间衍生的QRS波终点与使用R波峰值后固定时间间隔测量的幅度高度相关。使用两种不同算法时，ST段面积和ST段中点估计值差异很大。推导了回归方程，使得可以根据X导联的值估计V5导联的QRS波终点或ST60幅度，反之亦然。
