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QRS Complex and T Wave Detection using STFT


  • Department of Electricaland Electronics Engineering, Sikkim Manipal Institute of Technology (SMIT),SMU, Gangtok - 737102, Sikkim, India
  • Department of Electricaland Electronics Engineering, Sikkim Manipal Institute of Technology (SMIT), SMU, Gangtok - 737102, Sikkim, India
  • Department General Medicine, Central Referral Hospital and SMIMS, SMU, Gangtok - 737102, Sikkim, India


Objective: Precisely localize QRS complex and T wave of Electrocardiogram (ECG). Severe cardiovascular abnormalities like Ventricular Arrhythmias, Ventricular Hypertrophy, and Myocardial Infarction may occur due to the ventricular tissue dysfunctioning. The morphological changes in QRS and T wave of ECG represent the depolarization and repolarization disturbances and analysis of these segments alone may lead to identifying certain acute cardiac condition. Methodology: Presented algorithm comprises of three stages; 1. Pre-processing of input ECG signal (High-pass filter and Kalman filter), 2. Elimination of P wave (Difference Operation Method and Wavelet Transform), 3. Detection of QRS and T wave using Short Term Fourier Transform (STFT). Findings: The algorithm efficiency is evaluated with standard MIT-BIH Arrhythmia database. The Sensitivity (Se) and the Specificity (Sp) for QRS complex is found to be 99.59% and 99.53%, whereas for T wave it is of 99.50% and 99.44% respectively. Application/Scope: This algorithm could be implemented in real-time ECG analyzer for possible detection of ventricular chronic heart disease and may reduce the risk of sudden cardiac death.


MIT-BIH Arrhythmia Database, Pre-Processing, QRS Complex, STFT, T Wave.

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