Improving Diagnosis of Heart Disease by Analyzing Chaotic Indices of ECG Signals

Subject Areas : Renewable energy

Ali Tamizi ¹ , Mohammad Ataei ² , Mohammad Reza Yazdchi ³

1 - MSc/Najafabad Branch, Islamic Azad University
2 - Associated Professor/Univesity of Isfahan
3 - Assistant Professor/University of Isfahan

Received: 2011-09-04 Accepted : 2012-04-21 Published : 2013-06-01

Keywords: Lyapunov Exponent, Electrocardiogram, Correlation dimension, Chaotic signals, Fuzzy classifier,

Abstract :

Electrocardiogram (ECG) signals are the most popular non-invasive approach for diagnosis of heart irregularities and indications of possible heart diseases. Previous studies have shown that ECG signals do not have a linear distribution and contain a variety of non-linear dimensions. In the present research we have treated the ECG signals as time-series data and applied chaos indices analysis. Utilizing data from MIT_BIH Database, the present study has improved the past research by analysing chaotic indices  such as Lyapunov Exponent (λmax), and Correlation Dimension to ECG signal data from healthy individuals and heart patients. We present appropriate algorithms for reconstruction of Phase Space and estimations of the model parameters using Lyapunov Exponent and CorrelationDimension.We then present the results from reconstruction of Phase Space based on chaotic indices, and fuzzy classifier, to discriminate healthy individuals (NSR) from the heart patients.The heart patients include those with Arterial Fibrillation (AF) and those with Left Bundle Branch Block (LBBB). These results ascertain the effectiveness of application of chaotic distribution to ECG data in improving the heart disease diagnosis.