Hren R, Stroink G, Horácek B M
Nora Eccles Harrison Cardiovascular Research & Training Institute, University of Utah, Salt Lake City 84112, USA.
Med Biol Eng Comput. 1998 May;36(3):323-9. doi: 10.1007/BF02522478.
Different factors are investigated that may affect the accuracy of an inverse solution that uses a single-dipole equivalent generator, in a standardised inhomogeneous torso model, when localising the pre-excitation sites. An anatomical model of the human ventricular myocardium is used to simulate body surface potential maps (BSPMs) and magnetic field maps (MFMs) for 35 pre-excitation sites positioned on the epicardial surface along the atrioventricular ring. The sites of pre-excitation activity are estimated by the single-dipole method, and the measure for the accuracy of the localisation is the localisation error, defined as the distance between the location of the best-fitting single dipole and the actual site of pre-excitation in the ventricular model. The findings indicate that, when the electrical properties of the volume conductor and lead positions are precisely known and the 'measurement' noise is added to the simulated BSPMs and MFMs, the single-dipole method optimally localises the pre-excitation activity 20 ms after the onset of pre-excitation, within 0.71 +/- 0.28 cm and 0.65 +/- 0.30 cm using BSPMs and MFMs, respectively. When the standard torso model is used to localise the sites of onset of the pre-excitation sequence initiated in four individualised torso models, the maximum errors are as high as 2.6-3.0 cm (even though the average error, for both the BSPM and MFM localisations, remains within the 1.0-1.5 cm range). In spite of these shortcomings, it is thought that single-dipole localisations can be useful for non-invasive pre-interventional planning.
研究了不同因素，这些因素可能会影响在标准化非均匀躯干模型中使用单偶极等效发生器进行逆解以定位预激部位时的准确性。使用人类心室心肌的解剖模型来模拟沿房室环位于心外膜表面的35个预激部位的体表电位图（BSPM）和磁场图（MFM）。通过单偶极方法估计预激活动的部位，定位准确性的度量是定位误差，定义为最佳拟合单偶极的位置与心室模型中预激实际部位之间的距离。研究结果表明，当体积导体的电学特性和导联位置精确已知，并且将“测量”噪声添加到模拟的BSPM和MFM中时，单偶极方法在预激开始后20毫秒能最佳地定位预激活动，使用BSPM和MFM时分别在0.71±0.28厘米和0.65±0.30厘米范围内。当使用标准躯干模型来定位在四个个体化躯干模型中启动的预激序列的起始部位时，最大误差高达2.6 - 3.0厘米（尽管BSPM和MFM定位的平均误差仍在1.0 - 1.5厘米范围内）。尽管存在这些缺点，但认为单偶极定位对于非侵入性干预前规划可能是有用的。
