Hu Min, Jang Chengfan, Wang Suxia
Department of Echocardiogram and Electrocardiogram, the People's Hospital of Huangshan, Huangshan, Anhui 245000,
Department of Echocardiogram and Electrocardiogram, the People's Hospital of Huangshan, Huangshan, Anhui 245000, P.R.China.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2018 Feb 25;35(1):25-30. doi: 10.7507/1001-5515.201607048.
Lorenz plot (LP) method which gives a global view of long-time electrocardiogram signals, is an efficient simple visualization tool to analyze cardiac arrhythmias, and the morphologies and positions of the extracted attractors may reveal the underlying mechanisms of the onset and termination of arrhythmias. But automatic diagnosis is still impossible because it is lack of the method of extracting attractors by now. We presented here a methodology of attractor extraction and recognition based upon homogeneously statistical properties of the location parameters of scatter points in three dimensional LP (3DLP), which was constructed by three successive RR intervals as , and axis in Cartesian coordinate system. Validation experiments were tested in a group of RR-interval time series and tags data with frequent unifocal premature complexes exported from a 24-hour Holter system. The results showed that this method had excellent effective not only on extraction of attractors, but also on automatic recognition of attractors by the location parameters such as the azimuth of the points peak frequency ( ) of eccentric attractors once stereographic projection of 3DLP along the space diagonal. Besides, was still a powerful index of differential diagnosis of atrial and ventricular extrasystole. Additional experiments proved that this method was also available on several other arrhythmias. Moreover, there were extremely relevant relationships between 3DLP and two dimensional LPs which indicate any conventional achievement of LPs could be implanted into 3DLP. It would have a broad application prospect to integrate this method into conventional long-time electrocardiogram monitoring and analysis system.
洛伦兹图(LP)方法能够提供长时间心电图信号的全局视图,是一种用于分析心律失常的高效且简单的可视化工具,提取出的吸引子的形态和位置可能揭示心律失常发生和终止的潜在机制。但由于目前缺乏吸引子提取方法,自动诊断仍然无法实现。我们在此提出了一种基于三维洛伦兹图(3DLP)中散点位置参数的均匀统计特性的吸引子提取与识别方法,3DLP是在笛卡尔坐标系中由三个连续的RR间期作为x、y和z轴构建而成。在一组RR间期时间序列以及从24小时动态心电图系统导出的伴有频繁单源性早搏复合波的标签数据上进行了验证实验。结果表明,该方法不仅在吸引子提取方面具有出色的效果,而且在通过沿空间对角线对3DLP进行立体投影后,利用诸如偏心吸引子的点峰值频率( )方位等位置参数对吸引子进行自动识别方面也表现出色。此外, 仍是鉴别房性和室性期前收缩的有力指标。额外的实验证明该方法在其他几种心律失常中也同样适用。而且,3DLP与二维LP之间存在极其相关的关系,这表明任何传统的LP成果都可以融入到3DLP中。将该方法集成到传统的长时间心电图监测与分析系统中具有广阔的应用前景。