利用小波变换的方法检测心电信号的QT间期

主要介绍尝试一种新的方法对心电信号的QT间期进行检测。QT间期指心电波形中QRS波起点到T波终点这一段所对应的时间间隔,代表心室去极化过程。QT间期及其变异对于预测恶性心率失常具有一定准确性和临床意义。小波变换是一种信号的时间-尺度分析方法,它具有多分辨率的特点即对于信号的低频部分具有较高的频率分辨率和较低的时间分辨率,在信号高频部分具有较高的时间分辨率和较低的频率分辨率。根据QT间期起始点的特点选择高斯函数的二阶导数作为小波基,并用其对心电信号进行多尺度变换,观察结果选择QRS波起点、T波终点特征明显的波形作间期检测对象。将检测结果转化成校正QT间期—QTC,转化后可进一步评测间期长短,对疾病进行预测。

Wavelet transform for QT interval measurement in ordinary ECG

This paper mainly introduces a new method for detection of QT interval in ordinary ECG. As the interval between QRS waves and T wave in ECG, QT interval represents the depolarization of ventricle. QT interval and its aberrance can be used to forecast malignant abnormalities of heart rate. Wavelet transform is a time scale analysis method of the signal. It has a high frequency resolution and a low time resolution for the low-frequency part of the signal, and has a high time resolution and a low frequency resolution for the high-frequency part. On the basis of the characteristics of the starting point of QT interval, the second derivative of Gaussian function is adopted as the wavelet basis and applied to multi-scale transform of ECG signal. The waveforms with QRS waves as starting point and T wave as the end point are selected as the subjects. Then the measurement result is transformed into corrected QT interval, that is, QTC. QTC can be applied to forecasting the diseases.