Cabo C, Wharton J M, Wolf P D, Ideker R E, Smith W M
Department of Medicine, Duke University Medical Center, Durham, NC 27710.
IEEE Trans Biomed Eng. 1990 May;37(5):500-8. doi: 10.1109/10.55640.
We have developed and tested several detectors of local activations in unipolar cardiac electrograms; the detectors are based on the frequency content of the waveforms. For this study, myocardial regions with no local electrical activity were created with cryoablation in canine ventricles, so that the characteristics of electrograms reflecting local activation could be compared with those with only distant electrical activity. For each electrogram, representations of the original signal were created using the output of bandpass filters; for each representation, the value of the maximum amplitude was taken as a measurement of the frequency content of the electrogram in that frequency band. The content of each frequency band and the first derivative of the signal were tested as discriminators between local and distant electrical activity. Combinations of frequency bands were also tested using a logistic regression technique; certain combinations provided better detection than any of the individual frequencies or the first derivative. The inclusion of frequencies between 500 and 1000 Hz improved the detection performance, suggesting that sampling rates of 1000 samples per second or less may not be adequate for optimal discrimination. A detector based on multivariate analysis of different frequency components of a signal may be more effective than single-band filtering in discriminating between local and distant electrical activity in the heart, especially when those components have very different magnitudes.
我们已经开发并测试了几种单极心脏电图中局部激活的检测器；这些检测器基于波形的频率成分。在本研究中，通过在犬心室中进行冷冻消融来创建没有局部电活动的心肌区域，以便将反映局部激活的电图特征与仅具有远处电活动的电图特征进行比较。对于每个电图，使用带通滤波器的输出创建原始信号的表示；对于每个表示，将最大幅度值作为该频带中电图频率成分的度量。测试每个频带的内容以及信号的一阶导数作为局部和远处电活动之间的判别指标。还使用逻辑回归技术测试了频带组合；某些组合提供了比任何单个频率或一阶导数更好的检测效果。包含500至1000赫兹之间的频率可提高检测性能，这表明每秒1000个样本或更低的采样率可能不足以实现最佳判别。基于对信号不同频率成分进行多变量分析的检测器在区分心脏中的局部和远处电活动方面可能比单带滤波更有效，尤其是当这些成分的幅度非常不同时。
