Rautaharju P M, Park L, Rautaharju F S, Crow R
EPICARE Center, Department of Public Health Sciences, Bowman Gray School of Medicine, Winston-Salem, North Carolina 27104, USA.
J Electrocardiol. 1998 Jan;31(1):17-29. doi: 10.1016/s0022-0736(98)90003-6.
Continuing uncertainty exists about standardized procedures for the placement of electrocardiographic (ECG) chest electrodes, technical variability being the largest error source for short-term variations in amplitudes and waveforms of the chest lead ECGs. To avoid presumed attenuation of ECG amplitudes by abundant breast tissue, anterolateral chest electrodes in women are often placed under the breasts and too low. There is also considerable uncertainty about locating the midclavicular line and the V4 electrode, particularly in obese persons and in women. We examined the effect of breast tissue protuberance on ECG amplitudes using ECG and anthropometric data on 6,814 women included in the Atherosclerosis Research in Communities Study (ARIC). The R wave amplitudes in anterolateral chest leads and the Sokolow-Lyon voltage decreased (P < .001 for all), and RaVL and the Cornell voltage increased significantly with increasing breast protuberance (P < .001 for all). However, these effects were small (15 microV or less for each 1-cm increment in breast protuberance), and R2 values were less than .01, indicating that breast protuberance alone explained less than 1% of ECG amplitude variations. When chest size and breast protuberance estimates were entered simultaneously into a multivariate regression model, chest size appeared to dominate, and model R2 values increased for positive associations with RaVL (R2 = .12) and the Cornell voltage (R2 = .04). Combined model R2 values remained < or =.01 for all other ECG amplitudes. A detailed step-by-step standardized electrode placement procedure was formulated. Because of the difficulties encountered in locating the left midclavicular line by visual inspection, we introduced well-defined procedures for identification and documentation of lateral chest electrode placement locations as a quality control method for clinical trials. Population data from the Third National Health and Nutrition Survey on the distributions by sex and race of chest electrode V4 and V6 locations and anthropometric data on chest size and shape are presented in order to facilitate evaluation of the comparability of electrode placement procedures in various studies and for quality control in clinical trials. It is concluded that standardized procedures to document chest electrode placement locations are feasible. Breast tissue appears to have a practically negligible effect on ECG amplitudes, and in women, the placement of chest electrodes on the breast rather than under the breast is recommended in order to facilitate the precision of electrode placement at the correct horizontal level and at the correct lateral positions.
心电图（ECG）胸部电极放置的标准化程序仍存在不确定性，技术变异性是胸部导联心电图振幅和波形短期变化的最大误差来源。为避免因丰富的乳房组织导致心电图振幅衰减，女性的前外侧胸部电极常放置在乳房下方且位置过低。在确定锁骨中线和V4电极位置方面也存在相当大的不确定性，尤其是在肥胖者和女性中。我们利用社区动脉粥样硬化研究（ARIC）中纳入的6814名女性的心电图和人体测量数据，研究了乳房组织隆起对心电图振幅的影响。随着乳房隆起增加，前外侧胸部导联的R波振幅和索科洛夫 - 里昂电压降低（均P <.001），而RaVL和康奈尔电压显著增加（均P <.001）。然而，这些影响较小（乳房隆起每增加1厘米，变化幅度为15微伏或更小），且决定系数R2值小于.01，表明仅乳房隆起只能解释不到1%的心电图振幅变化。当将胸围大小和乳房隆起估计值同时纳入多元回归模型时，胸围大小似乎起主导作用，与RaVL（R2 =.12）和康奈尔电压（R2 =.04）呈正相关的模型R2值增加。对于所有其他心电图振幅，组合模型R2值仍≤.01。制定了详细的逐步标准化电极放置程序。由于通过目视检查确定左锁骨中线存在困难，我们引入了明确的程序来识别和记录外侧胸部电极放置位置，作为临床试验的质量控制方法。呈现了第三次全国健康与营养调查中关于胸部电极V4和V6位置按性别和种族分布的人群数据以及胸围大小和形状的人体测量数据，以便于评估不同研究中电极放置程序的可比性以及临床试验中的质量控制。得出的结论是，记录胸部电极放置位置的标准化程序是可行的。乳房组织对心电图振幅的影响实际上可以忽略不计，对于女性，建议将胸部电极放置在乳房上而非乳房下方，以便于在正确的水平和横向位置精确放置电极。
