Hirai M, Suzuki A, Hayashi H, Tomita Y, Adachi M, Ichihara Y, Terazawa T, Takatsu F, Saito H
First Department of Internal Medicine, University of Nagoya School of Medicine, Japan.
Am J Cardiol. 1992 Oct 15;70(11):984-9. doi: 10.1016/0002-9149(92)90348-3.
The effects of right ventricular pacing, which simulated left bundle branch block (BBB), on QRST time-integral values of 12-lead electrocardiograms (ECGs) were examined, and the clinical usefulness of QRST values for estimating the severity of left ventricular wall motion abnormalities due to a prior anterior wall myocardial infarction (MI) in the setting of left BBB were evaluated. Digitized ECGs were recorded during normal sinus rhythm and simulated left BBB in 38 patients (24 with and 14 without prior anterior wall MI). QRST values were calculated in each lead point of 12-lead ECGs. Data from 608 normal subjects were used as control values; the mean +/- 2 SD of these values was regarded as the normal range. The parameter sigma DE was defined as the sum of the differences between the normal mean QRST value and the QRST values of a given patient in leads where the QRST value was less than the normal range. The correlation coefficient of sigma DE for the 2 activation sequences was highly significant. Although small but significant changes were seen in QRST values in leads I, II, III, aVR, aVF and V1 during simulated left BBB, left precordial leads showed no significant changes in QRST values. A criterion of sigma DE > 40 mV.ms for detecting an anterior wall MI showed a sensitivity of 88%, a specificity of 93%, and a diagnostic accuracy of 89%. The sigma DE was significantly (p < 0.001) correlated with the asynergy index calculated from left ventriculograms.(ABSTRACT TRUNCATED AT 250 WORDS)
研究了模拟左束支传导阻滞（BBB）的右心室起搏对12导联心电图（ECG）的QRST时间积分值的影响，并评估了QRST值在估计左束支传导阻滞情况下既往前壁心肌梗死（MI）所致左心室壁运动异常严重程度方面的临床实用性。在38例患者（24例有既往前壁心肌梗死，14例无既往前壁心肌梗死）中记录了正常窦性心律和模拟左束支传导阻滞时的数字化心电图。计算12导联心电图各导联点的QRST值。将608名正常受试者的数据用作对照值；这些值的平均值±2标准差被视为正常范围。参数sigma DE定义为正常平均QRST值与QRST值低于正常范围的给定患者各导联QRST值之间差异的总和。两种激动顺序的sigma DE的相关系数高度显著。虽然在模拟左束支传导阻滞期间，I、II、III、aVR、aVF和V1导联的QRST值出现了虽小但显著的变化，但左胸前导联的QRST值没有显著变化。检测前壁心肌梗死的sigma DE>40 mV.ms的标准显示敏感性为88%，特异性为93%，诊断准确性为89%。sigma DE与根据左心室造影计算的协同失调指数显著相关（p<0.001）。（摘要截短于250字）
