Tate Jess D, Good Wilson, Zemzemi Nejib, Boonstra Machteld, van Dam Peter, Brooks Dana H, Narayan Akil, MacLeod Rob S
University of Utah, Salt Lake City, USA.
Acutus Medical, INC. Carlsbad, CA, USA.
Funct Imaging Model Heart. 2021 Jun;12738:515-522. doi: 10.1007/978-3-030-78710-3_49. Epub 2021 Jun 18.
Despite advances in many of the techniques used in Electrocardiographic Imaging (ECGI), uncertainty remains insufficiently quantified for many aspects of the pipeline. The effect of geometric uncertainty, particularly due to segmentation variability, may be the least explored to date. We use statistical shape modeling and uncertainty quantification (UQ) to compute the effect of segmentation variability on ECGI solutions. The shape model was made with Shapeworks from nine segmentations of the same patient and incorporated into an ECGI pipeline. We computed uncertainty of the pericardial potentials and local activation times (LATs) using polynomial chaos expansion (PCE) implemented in UncertainSCI. Uncertainty in pericardial potentials from segmentation variation mirrored areas of high variability in the shape model, near the base of the heart and the right ventricular outflow tract, and that ECGI was less sensitive to uncertainty in the posterior region of the heart. Subsequently LAT calculations could vary dramatically due to segmentation variability, with a standard deviation as high as 126ms, yet mainly in regions with low conduction velocity. Our shape modeling and UQ pipeline presented possible uncertainty in ECGI due to segmentation variability and can be used by researchers to reduce said uncertainty or mitigate its effects. The demonstrated use of statistical shape modeling and UQ can also be extended to other types of modeling pipelines.
尽管心电图成像（ECGI）中使用的许多技术都取得了进展，但该流程的许多方面的不确定性仍未得到充分量化。几何不确定性的影响，尤其是由于分割变异性导致的影响，可能是迄今为止探索最少的。我们使用统计形状建模和不确定性量化（UQ）来计算分割变异性对ECGI解决方案的影响。形状模型是使用Shapeworks从同一患者的九次分割中构建的，并纳入了一个ECGI流程。我们使用UncertainSCI中实现的多项式混沌展开（PCE）计算心包电位和局部激活时间（LAT）的不确定性。分割变化引起的心包电位不确定性反映了形状模型中高变异性区域，靠近心脏底部和右心室流出道，并且ECGI对心脏后部区域的不确定性不太敏感。随后，由于分割变异性，LAT计算可能会有很大差异，标准差高达126毫秒，但主要在传导速度较低的区域。我们的形状建模和UQ流程展示了由于分割变异性导致的ECGI中可能存在的不确定性，研究人员可以使用它来减少所述不确定性或减轻其影响。所展示的统计形状建模和UQ的应用还可以扩展到其他类型的建模流程。
