7/29/2019 Detection of Heart Blocks in ECG Signals by Spectrum and Time-Frequency Analysis

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4thStudent Conference on Research and Development (SCOReD 2006), Shah Alam, Selangor, MALAYSIA, 27-28 June, 2006

Detection of Heart Blocks in ECG Signals bySpectrum and Time-Frequency Analysis

Norhashimah Mohd Saad1, Abdul Rahim Abdullah2, and Yin Fen Low1

1

Faculty of Electronics and Computer EngineeringKolej Universiti Teknikal Kebangsaan MalaysiaLocked Bag 1200, Ayer Keroh, 75450 Malacca, Malaysia

2Faculty of Electrical EngineeringKolej Universiti Teknikal Kebangsaan Malaysia

Locked Bag 1200, Ayer Keroh, 75450 Malacca, Malaysia

Abstract The electrocardiogram (ECG) is a non-invasive testthat records the electrical activity of the heart and is importantin the investigation of cardiac abnormalities. Each portion of theECG waveform carries various types of information for thecardiologists analyzing patients heart condition. ECGinterpretation at the present time remains dependent manually

in time domain. It is difficult for the cardiologists to make acorrect diagnosis of cardiac disorder. A computerizedinterpretation of ECG is needed in order to make the diagnosismore efficient. This paper discusses the use of digital signalprocessing approach for the detection of heart blocks in ECGsignals. Signal analysis techniques such as the periodogrampower spectrum and spectrogram time-frequency analysis areemployed to analyze ECG variations. Seven subjects areidentified: normal, first degree heart block, second degree heartblock type I, second degree heart block type II, Third degreeheart block, right bundle branch block and left bundle branchblock. Analysis results revealed that normal ECG subject is ableto maintain higher peak frequency range (8 Hz), while heartblock subjects revealed a significant low peak frequency range (