Nakai K, Ito C, Koh E, Miyakawa T, Mizunuma Y, Ichikawa T, Motegi I, Suzuki T, Kato M, Takahashi T
Department of Clinical Pathology, Iwate Medical University School of Medicine, Morioka.
J Cardiol. 1988 Mar;18(1):207-15.
Comparative evaluations of the percent of the perimetric circumference of infarction and cardiac performance for the occurrence of late potential were performed in 12 normal subjects and 22 patients with old myocardial infarction (MI). All patients were in normal sinus rhythm without bundle branch block. Bipolar X, Y, and Z leads were signal-averaged using a bandpass filter with a low-cut frequency of 100 Hz and a high-cut frequency of 300 Hz. The filtered signals for the three leads were displayed and combined into a vector magnitude, square root of X2 + Y2 + Z2. The percent ratio of the root mean square voltage in the last 40 msec of the QRS complex was calculated against that of the total filtered QRS (%RMS40). The value of the standard deviation (SD) in the phase distribution was obtained by the Fourier analysis of multi-gated blood pool images. Significant differences were observed among MI with late potential, MI without it and the normal subjects for %RMS 40 (5.7 +- 2.8% vs 26.9 +- 8.1, 37.5 +- 10.8%). Left ventricular ejection fraction was lower in MI with late potential (19.7 +- 7%) compared to that of MI without it (33 +- 18%) and the normal subjects (60 +- 4%); the value of SD was higher in MI with late potential (64 +- 21 degrees), compared to that of MI without it (43 +- 20 degrees) and the normal subjects (9 +- 4 degrees). These findings showed that the percent ratio of the last 40 msec RMS voltage (%RMS 40) was found to discriminate effectively among MI with and without late potential and normal subjects. It was suggested that the amount and structure of the infarcts may be important factors in the occurrence of late potential.
对12名正常受试者和22名陈旧性心肌梗死（MI）患者进行了梗死周长百分比和心脏功能与晚电位发生情况的比较评估。所有患者均为正常窦性心律，无束支传导阻滞。使用低截止频率为100Hz、高截止频率为300Hz的带通滤波器对双极X、Y和Z导联进行信号平均。显示三个导联的滤波信号并将其组合成矢量大小，即X2 + Y2 + Z2的平方根。计算QRS波群最后40毫秒的均方根电压与总滤波QRS电压的百分比比值（%RMS40）。通过多门控血池图像的傅里叶分析获得相位分布的标准差（SD）值。在有晚电位的MI、无晚电位的MI和正常受试者之间，观察到%RMS 40存在显著差异（5.7±2.8%对26.9±8.1%，37.5±10.8%）。有晚电位的MI患者左心室射血分数（19.7±7%）低于无晚电位的MI患者（33±18%）和正常受试者（60±4%）；有晚电位的MI患者SD值（64±21度）高于无晚电位的MI患者（43±20度）和正常受试者（9±4度）。这些结果表明，QRS波群最后40毫秒均方根电压百分比比值（%RMS 40）能有效区分有和无晚电位的MI患者以及正常受试者。提示梗死灶的大小和结构可能是晚电位发生的重要因素。
