房颤病人体表标测信号的f波提取方法研究

Research on f wave extraction methods of body surface potential mapping recordings from patients with atrial fibrillation

体表标测是一种无创的心电标测技术,在房颤的相关研究中得到了越来越多的应用。房颤病人的体表标测信号可以看做是心室信号、心房信号以及噪声信号三路统计独立的源信号瞬时线性混合而成。为了提取体表标测信号的心房活动(f波),利用独立成分分析(ICA)以及ICA与二阶盲辨识法(SOBI)结合的两种盲信号分离方法 ICA-SOBI法对9位房颤病人的体表标测信号进行f波提取。对提取的结果采用频谱集中度(SC)评价。统计结果表明ICA-SOBI法提取的f波SC较高,提取效果更理想。同时,用ICA-SOBI法对不同子区域的体表标测信号进行f波提取,发现与心脏最接近的体表区域提取的f波SC最高,这一结果对体表电极点的空间分布设计有一定的指导意义。

Body surface potential mapping （BSPM）is a noninvasive electrocardiographic technique and gains more and more applications in the study of atrial fibrillation.BSPMrecordings of the patients with atrial fibrillation can be modelled as an instant linear mixture of three statistically independent source signals of ventricular and atrial activities as well as noise signal.In order to extract the atrial activity （f wave）from BSPMrecordings,two kinds of blind signal separation methods were applied,which are （ICA）method and the combination of ICA and （SOBI）called ICA-SOBI method.The two methods were applied on nine patients with atrial fibrillation to extract the f wave from the BSPM recordings.The spectral concentration （SC）was adopted as the evaluation index to evaluate the extracted result.Statistical result shows that the f waves extracted with ICA-SOBI method have higher SC and the extraction effect is much better.Meanwhile,the ICA-SOBI method was used to extract the f waves from the BSPMrecordings at different sub-regions.The f wave extracted from the region nearest to the heart shows the highest SC;and this result can be a guidance for the spatial distribution design of the electrodes for BSPM.